SYSTEMS AND METHODS FOR RAPID ESTABLISHMENT

OF OFFSHORE NUCLEAR POWER PLATFORMS

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] T his application relies for priority on U.S. Provisional Patent Application Serial No. 62/646,614, entitled“SYSTEMS AND METHODS FOR RAPID ESTABLISHMENT OF OFFSHORE NUCLEAR POWER PLATFORMS,” filed March 22, 2018, the entire content of which is hereby incorporated by reference.

FIELD OF THE INVENTION

[0002] The present invention relates to the establishment of coastal platforms housing nuclear power facilities

BACKGROUND

[0003] The global need for reliable, safe, secure, and inexpensive energy is growing rapidly. Consumers of electricity, heat, utilities, agricultural products, and industrial commodities require energy sources that are sustainable, low-cost, produce low carbon emissions, and have high capacity factor. Novel nuclear power plant designs can meet this need. To overcome the drawbacks of earlier nuclear plant designs, such plants should be adaptable to areas with existing nuclear plant infrastructure, minimize development footprint (e.g., near expanding coastal population centers), and entail the least possible development of new transmission infrastructure. To be secure and sustainable, they must be robust against potential impacts of climate change, including sea level rise and dwindling supplies of freshwater for cooling. They should also be robust against mechanical failures, malicious attack, human error, and natural disasters, including seismic events and tsunamis. Low population density in proximity to development sites is preferable because it mitigates emergency-planning concerns. Also, novel designs should avoid the high cost and exceedingly long construction times that result from complex processes involved in finding and approving suitable sites, from accessing remote sites, and from ad-hoc construction processes that vary' from site to site. Site-specific design, approval, and construction processes result in high construction costs and long project durations that make nuclear power projects difficult to finance and insure. A need thus exists for methods and systems that standardize nuclear plant design and construction, allowing for faster design and deployment to a wider range of available sites.

[0004] Finally, novel baseload generating sources should complement increasing renewables penetration, have load-following capabilities energy markets in developing nations, and optionally provide low-carbon process heat generation to co-located facilities producing locally valuable commodities.

[0005] Prefabricated nuclear platforms (PNPs), e.g., units that house or support nuclear power plants, may be partly or wholly produced in maritime or terrestrial manufacturing facilities and then towed via seas or waterways to coastal deployment sites, can meet the entire range of foregoing needs. For example, PNPs stationed in the shoreface zone require relatively little onshore land development (mostly for landfall of transmission lines and logistics support hubs) and are surrounded by an inexhaustible supply of coolant water. Security concerns are mitigated by open sea-and-air environment of a coastal PNP, which makes any form of approach relatively easy to detect.

[0006] Sectional manufacture and modular assembly using well-known“design for build” techniques that consider manufacturing facility capabilities can lower PNP cost as compared to terrestrial construction of a comparable-sized plant because preassembled module size is severely constrained on land by the difficulties of overland transport and the limited lifting capacities of construction cranes. Practical shipyard module size is at least an order of magnitude greater than for terrestrial construction, and the design of such a module can be organized on the basis of efficiency and engineering considerations. (Herein, the term

“shipyards” includes manufacturing facilities that can receive or deliver relatively large components, vessels, platforms, and other units by flotation, and the term“factories” includes manufacturing facilities that are confined to receiving and delivering various built units by overland transportation.) Additionally, site-specific variations in context (terrain, geohydrology, settlement patterns, etc.), which have invariably raised construction costs for land-based nuclear plants despite efforts to standardize designs, are greatly mitigated for PNPs. Also, in some design cases PNPs can be relocated (e.g., for re-deployment, in response to changing security concerns, or for transport to a decommissioning location), in contrast to standard terrestrial nuclear power plants. [0007] Thus, PNPs potentially offer an elegant solution to some of the most intractable costs of conventional, onshore nuclear power plants. Moreover, PNPs can be advantageously combined with another important recent innovation in nuclear power, i .e., commercially viable small modular reactors (SMRs), e.g., the NuScale Power Module™, which generates a quantity of steam capable of supporting an electrical power output of approximately 50 megawatts (MWe). SMRs offer a number of potential advantages over the relatively large (gigawatt-scale) nuclear reactors conventionally employed for commercial power generation; these advantages include but are not limited to lower accident risk due to passive internal coolant circulation, standardized mass manufacture, adjustment of total generating capacity of a multi-SMR facility by addition or removal of SMRs, swap-out and refueling capability for individual SMRs at a multi-SMR facility without shutdown of the whole facility, and ability to be delivered by truck or barge as enabled by small SMR form factor (e.g., <5 meters wide by 20 meters high).

[0008] It is desirable that the advantages of coastal PNPs be combined with the advantages of SMRs. However, in the prior art, proposals for floating PNPs entail shipbuilding on a very large structural scale not hitherto demonstrated, most likely with novel challenges and high corresponding costs difficult to mitigate by economies of scale— the“built like cathedrals, not like cell phones” problem— while proposals of the prior art for grounded (non-floating) PNPs do not provide for the most rapid, flexible, and affordable fixation of platforms or other units to the sea floor, floors of artificial harbors, or other submerged sites. Moreover, prior methods tend to require elaborate, expensive preparation (e.g., leveling and surfacing) of underwater sites and are unsuitable for sloping seabed locations. Hereinafter, for simplicity, any ground surface that is usually or always submerged shall be referred to as“the seabed.”

[0009] There is therefore a need for systems and methods of stably stationing PNPs, preferably PNPs comprising SMRs, upon the coastal seabed in coastal settings in a relatively rapid, flexible, affordable manner.

SUMMARY

[0010] Provided herein are methods and systems for the flexible, rapid installation of premanufactured nuclear plants (PNPs) comprising small modular reactors (SMRs) by using staged pilings (SPs) to establi sh one or more base structures upon the sea floor and then affixin: one or more modules containing a nuclear reactor or ancillary facilities to the one or more base structures.

[0011] Various embodiments of the invention include nuclear power generating stations comprising facilities preferably manufactured in a modular, standardized manner in shipyards and delivered by flotation to coastal sites. The modules, once installed, essentially constitute a nuclear power generating station and are installed in a multistage process. In an example, this process entails installation of a floatable, removal seabed base structure confi gured to be supported above or affixed to the seabed by means of staged pilings, using techniques to be exampled clearly hereinbelow. The seabed base structure preferably comprises an upwards- extending wail structure, arranged along at least a part of the periphery of the base structure, the base structure also being provided with an opening in the wall structure for allowing a floatable module to be berthed in and then supported by the seabed base structure. Thus, in an illustrative embodiment, one or more seabed base structures are floated to a coastal site, staged pilings are used to install the one or more of the seabed base structures, one or more additional modules (e.g., a reactor module) are floated to the coastal site, and the one or modules are installed upon the seabed base structures and interconnected with each other and with coastal facilities so as to produce a functional power generation facility

[0012] Nuclear power plants of any physical size or power rating are contemplated and within the scope of the invention in various embodiments. However, PNPs containing SMRs are preferred because SMRs are of small size compared to traditional terrestrial nuclear power plants. The latter would be relatively difficult to house in mobile modules of practical size, whereas SMRs can be so housed, and moreover can be delivered to and removed from a modular coastal installation separately from the modules that house them. Thus, modularization of a nuclear power generating station that relies on SMRs can extend to the reactors comprised by the station, not only to the supportive and ancillary physical plant of the station. Discussion hereinbelow therefore focuses upon PNPs comprising SMRs, extension and scaling of concepts to other forms of nuclear plant being understood.

[0013] The prior art has provided for manufacture of SMRs of various types and for their deployment, singly or in groups, in nuclear power stations of various configurations. The prior art has also provided for the installation by various means of single or multiple SMRs in floating or grounded configurations in bodies of water. All such deployments and configurations, and the methods by which they are built, are readily distinguishable from the methods and systems of embodiments of the invention, as shall be made clear hereinbelow.

[0014] In particular, the prior art includes a number of types of constructed sites (a La “artificial islands”) for nuclear power plants either adjacent to, surrounded by, or floating upon bodies of water such as rivers, lakes, oceans, or seas, the text Islands for Offshore Nuclear Power (Binnie & Partners, London, 1982), whose contents are incorporated herein by reference, describes a range of such constructed sites, which are further discussed hereinbelow with reference to several of the Figures. Herein, for simplicity, all sites at which PNPs are affixed to the sea floor (as defined hereinabove) are termed“coastal” or“littoral” sites. Also comprised by the prior art are methods for the delivery of certain components of power plants by flotation to prepared onshore or near-shore sites. The methods of the prior art include the use of dredged channels to enable the delivery of power-plant components to a coastal site where the

components may be grounded (e.g., by flooding and filling). The methods of the prior art also include partial disassembly of large reactor containments to enable passage along constrained delivery routes (e.g., the St. Lawrence Seaway); such disassembly requires technically difficult and therefore expensive welding assembly of the unified containment at the final installation site. The methods of the prior art also include the delivery and positioning (e.g., by grounding) of caissons for the construction of breakwaters or protective barriers around coastal plants. The methods of the prior art also include the deployment of SMRs in common enclosures, e.g , proposals by NuScale Power, Inc. for the colocation of some number of SMRs (e.g., six SMRs) of approximately 50 MW capacity each within a single structure, where the number of SMRs are immersed in a single coolant pool. The methods of the prior art also provide for the construction of vertically-oriented floating structures and structures grounded on the sea floor containing nuclear reactors.

[0015] The prior art has also provided for the installation of facilities for the storage and distribution of liquefied natural gas and/or other fluids using seabed base structures and various methods employing pilings, including what are herein termed staged-pilings methods, e.g., WO 2016/085347 Al,“Sea Bed Terminal for Offshore Activities” and WO 2017/168381 Al,

“Seabed Base Structure and Method for Installation of Same,” the entire disclosures of which are incorporated herein by reference. [0016] AH this prior art, as well as prior art not described herein, is fundamentally distinguishable from embodiments of the invention. Embodiments comprise systems and methods for the delivery of nuclear generation facilities or portions of such facilities, including but not limited to SMRs, structures to house and service multiple SMRs, and turbine houses, by flotation and/or land transport in a manner that provides for the special security needs of modern nuclear power stations and exploits the small size and other unique properties of integrated SMRs (e.g , self-containment of cores with primary heat-exchange loops). Embodiments of the invention advantageously enable potential separate delivery' by water and/or land of one or more SMRs, reactor facilities (structures that will house and service the SMRs), turbine facilities (structures that will house and service the turbines, generators, condensers, and auxiliary power conversion equipment), and aircraft impact shields to coastal sites and the installation of such modules and objects at such sites.

[0017] Among other things, the present invention provides an installation that includes a plurality of pilings securable to a bed under a surface of a body of water, a base structure disposed atop the plurality of pilings, and a module disposable on the base structure. The module is positioned and securable on the base structure after being floated on the surface of the body of water over the base structure.

[0018] In one contemplated embodiment the base structure has three sides adapted to extend above the surface of the body of water, thereby establishing an artificial harbor

[0019] It is contemplated that an external structure may be disposable on the base structure, adapted to encase the module therein.

[0020] In one embodiment, the external structure may be an aircraft impact protection structure. The aircraft impact protection structure may include a door adapted to permit the module to be inserted into the aircraft impact protection structure through the door.

[0021] It is also contemplated that the installation may include a plurality of seismic isolators disposed on top of the base structure, between the base structure and at least the module

[0022] The module may include a reactor module, which may be a nuclear reactor.

[0023] Still further, the installation may include a lacuna defined within the base structure and the plurality of pilings, permitting the nuclear reactor to be lowered partially or fully into the body of water, below' the surface, the plurality of pilings serving as a physi cal barrier from hazards threatening the nuclear reactor. [0024] The installation also may have a jacket surrounding the nuclear reactor, and a plurality of jacks supporting the jacket within the module. The plurality of jacks is

contemplated to lower the jacket into the lacuna and raise the jacket out of the lacuna.

[0025] In one embodiment, the module may he a power conversion module that may have a generator disposed therein.

[0026] Still further, the module may have a cooling module that may include a cooling tower.

[0027] In another embodiment, the present invention provides an installation that includes a base structure ballasted down and securable to a bed under a surface of a body of water and a module disposable on the base structure. The module is contemplated to be positioned and securable on the base structure after being floated on the surface of the body of water over the base structure.

[0028] In this embodiment, the installation also may include a lacuna defined within the base structure permitting the nuclear reactor to be lowered partially or fully into the body of water, below the surface into at least one of a natural or an artificial cavity within the bed.

[0029] In yet another embodiment, the installation may have a floating base structure securable to a bed under a surface of a body of water and a module disposable on the base structure. Here, the module is contemplated to be positioned and securable on the base structure after being floated on the surface of the body of water over the base structure.

[0030] In this embodiment, the installation may include a lacuna defined within the base structure, permi tting the nuclear reactor to be lowered partially or fully into the body of water, below the surface.

[0031] These and other distinguishing aspects of embodiments of the invention, along with various advantages of embodiments, will be clarified hereinbelow with reference to the Figures.

[0032] Of note, a system of terminology is adopted herein that succinctly classifies various units comprised by embodiments of the invention:

BRIEF DESCRIPTION OF THE FIGURES

[0033] In the drawings, like reference characters generally refer to the same parts throughout the different views. Also, the drawings are not necessarily to scale, emphasis instead generally being placed upon illustrating the principles of the invention.

[0034] Reference throughout the specification to“one embodiment” or“an embodiment” means that a particular feature, structure, or characteristic described in connection with an embodiment is included in at least one embodiment of the subject matter disclosed. Thus, the appearance of the phrases“in one embodiment” or“in an embodiment” in various places throughout the specification is not necessarily referring to the same embodiment.

[0035] In the following description, various embodiments of the present invention are described with reference to the following drawings, in which:

[0036] FIG, 1 shows schematically a first stage of the installation procedure, where two rows of aligned pilings in spaced relation are established;

[0037] FIG. 2 shows schematically a base structure to be supported by the pilings is towed into position between the two, spaced-apart, aligned rows of pilings by a towing vessel;

[0038] FIG. 3 shows schematically in perspective seen from below an embodiment of a base structure according to the present invention;

[0039] FIG. 4 shows schematically in perspective an embodiment of the base structure positioned and supported by the pilings in aligned position on at least both sides of the base structure;

[0040] FIG, 5 shows schematically in perspective two seabed base structures installed upon seabed base structures.

[0041] FIG. 6 shows schematically seismic isolation units upon a seabed base structure.

[0042] FIG. 7A shows schematically removable panels of the side walls of a seabed base structure.

[0043] FIG, 7B show's schematically a seabed base structure moored to the seabed via mooring lines.

[0044] FIGS, 8A, 8B, and 8G show schematically and by stages the docking of a floatable aircraft impact shield module in the artificial harbor proffered by a seabed base structure.

[0045] FIG, 9 shows schematically the operation of a door in the side of an aircraft impact shield module installed upon a seabed base structure. [0046] FIG, 10 shows schematically in cross section portions of a reactor module that is to be installed within an aircraft impact shield module installed upon a seabed base structure.

[0047] FIG. 11 show's schematically two modules installed upon two seabed base structures.

[0048] FIG. 12 show's schematically two modules installed upon two seabed base structures and a cooling tower installed upon pilings.

[0049] FIG. 13 shows schematically in vertical cross section a nuclear power plant module and a power conversion module.

[0050] FIG. 14 show's schematically in horizontal cross section the nuclear power plant module and the power conversion module of FIG. 13.

[0051] FIG. 15 shows schematically in side view portions of an SMR of the CAREM type.

[0052] FIG. 16 show's schematically in top-down view portions of an SMR of the CAREM type.

[0053] FIG. 17 show's schematically in perspective portions of an SMR of the CAREM type.

[0054] FIG. 18 shows schematically in vertical cross section portions of an SMR of the CAREM type installed within a floatable module.

[0055] FIG, 19 show's schematically in vertical cross section portions of a floatable module containing SMRs of the NuScale type and installed upon a seabed base structure.

[0056] FIG. 20 shows schematically in horizontal cross section portions of a floatable module containing SMRs of the NuScale type and installed upon a seabed base structure.

[0057] FIG, 21 shows schematically in horizontal cross section portions of a floatable module containing SMRs of the NuScale type as well as turbine-generator units and installed upon a seabed base structure.

[0058] FIG. 22A show's schematically in side view' portions of an SMR of the UK (Rolls Royce) type.

[0059] FIG, 22B shows schematically in top-down view portions of an SMR of the UK (Rolls Royce) type.

[0060] FIG. 23 shows schematically in horizontal cross section portions of a floatable module containing an SMR of the UK type and installed upon a seabed base structure.

[0061] FIG, 24 shows schematically in horizontal cross section portions of a floatable module containing an SMR of the SMART type and installed upon a seabed base structure. [0062] FIG, 25 shows schematically in horizontal cross section portions of a floatable module containing an SMR of the mPower type and installed upon a seabed base structure.

[0063] FIG. 26 show's schematically in perspective two seabed base structures installed upon seabed base structures, one of which comprises a central opening.

[0064] FIGS. 27A, 27B, and 27B show schematically in vertical cross section portions of a floatable module containing an SMR of the UK type and installed upon a seabed base structure as the SMR is lowered in stages through a central opening in the seabed base structure

[0065] FIG. 28 show's schematically in vertical cross section portions of an SMR of the NuSca!e type installed below waterline by means of a central opening in a seabed base structure

[0066] FIG. 29 show's schematically in vertical cross section portions of an SMR of the Integrated Modular Water Reactor type installed below' waterline by means of a central opening in a seabed base structure.

[0067] FIG, 30 shows schematically two modules installed upon seabed base structures in an artificially dredged channel.

[0068] FIG. 31 show's schematically four modules installed upon seabed base structures and interconnected by utility bridges.

[0069] FIG, 32 shows schematically in vertical cross section the stabilization of an embankment by means of the anchor-block slope stabilization technique;

[0070] FIG. 33 show's schematically in vertical cross section the stabilization of an embankment by means of bulkheads and piers

[0071] FIG, 34 show's schematically in vertical cross section portions of a module established upon a seabed base structure adjacent to a stabilized embankment.

[0072] FIG. 35 shows schematically in top-down view a nuclear power module and power conversion module installed within an artificially dredged U-shape channel.

[0073] FIG. 36A shows schematically in top-down view portions of a coastal power plant including an offshore artificial channel dredged to receive floatable modules

[0074] FIG, 36B shows the coastal power plant of FIG, 36A with floatable modules installed upon seabed base structures in the prepared offshore channel.

[0075] FIG, 37A shows schematically in top-down view portions of a coastal power plant including an artificial channel dredged in a shoreline to receive floatable nuclear power modules

[0076] FIG. 37B shows the coastal power plant of FIG. 37A with two floatable nuclear power modules installed upon seabed base structures in the prepared channel.

[0077] FIG. 38 show's a nuclear power station comprising two modules founded upon seabed base structures and located within an artificial cavern having stabilized walls and ceiling

[0078] FIG. 39 is a schematic depiction of relationships among portions of an illustrative deployment or application of a nuclear power plant according to an illustrative embodiment.

[0079] FIG. 40 is another schematic depiction of relationships among portions of an illustrative deployment or application of a nuclear power plant according to an illustrative embodiment.

[0080] FIG. 41 is yet another schematic depiction of relationships among portions of an illustrative deployment or application of a nuclear power plant according to an illustrative embodiment.

DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION

[0081] The present invention will now be described in connection with several contemplated embodiments. The discussion of specific embodiments is not intended to limit the scope of the present invention. To the contrary, the discussion of several embodiments is intended to illustrate the broad scope of the present invention. In addition, the present invention is intended to encompass variations and equivalents of the embodiments described herein,

[0082] FIG. 1 show¾ schematically a first stage 100 of an installation procedure according to an illustrative embodiment of the invention, where two rows of aligned pilings (e.g., pile or piling 104) are arranged, an additional pile or piling 106 being in process of being forced into the seabed 108 by means of a piling barge 110 with a crane 112 and a pile driving device 114 suspended from the crane 112. It is noted that the term“seabed” as used herein is intended to encompass any bed for any body of water and should not be understood to limit the present invention. Pilings are preferably of steel or reinforced concrete and are driven to an

approximate common depth 116 whose value depends on pile and seafloor physical characteristics and anticipated force loads. During this stage 100 the barge 110 may be moored by means of conventional seabed anchors and mooring lines (not shown). Numbers, sizes, and arrangements of pilings depicted in all figures herein are illustrative only; various embodiments depart from depicted embodiments in these and other respects.

[0083] FIG. 2 shows schematically a second stage 200 of the installation procedure of FIG. 1. In FIG. 2, a base structure 202 is being towed into position between the two row's of aligned temporary pilings 104, 106 by a towing vessel 204 and a pair of towing lines 206. The base structure 202, whose structure shall be further clarified with reference to FIG. 3, is provided with two outwards-projecting cantilevered ledges 208, 208' that extend outwards from the top of the base structure 202 along two parallel top sides thereof, each ledge 208, 208' being configured to rest atop a corresponding row of pilings 104, 106 The ledges 208, 208' are provided with strong points (e.g., strong point 210), each shaped (e.g., as a downward-facing socket) so as to rest securely atop a pile 104, 106 and collectively able to sustain the weight of the base structure 202 as well as other anticipated loads, forces, and bending moments that might impinge on the strong points (arising, e ., from wave action upon the base structure 202), at least during the installation stage of the base structure 202 until the base structure 202 is more securely piled to the seabed 108 In the state or stage of installation depicted in FIG. 2, the base structure 202 is not yet aligned with the pilings 104, 106 upon which it is intended to rest, moreover, the volumetric displacement of the base structure 202 is such that the ledges 208, 208' and their strong points ride above the tops of the pilings 104, 106, notwithstanding vertical displacements due to wave action during acceptable sea conditions for performing the installation stage 200. Also, various porti ons of the seabed base structure 202 are provided with buoyancy devices (not shown), where such buoyancy means may be in the form of floodable tanks and compartments. Thus, the seabed base structure 202 may be towed into place above the pilings intended to support it, then ballasted down upon the pilings by, e ., allowing w'ater to enter buoyancy compartments. Thereafter, strong points may be affixed securely and reversi bly to pilings 104, 106 (e.g., by transverse thole pins) to prevent untoward motion of the base structure 202.

[0084] The seabed base structure 202 also comprises an inwards-projecting beam framework or structure 212, also conceivable as a perforated horizontal platform, and upwards-extending wall structures 214, 214', 214" arranged along three sides of the peri phery of the base structure 202. The wall structures 214, 214', 214", together with the beam structure 212 and ledges 208, 208', together constitute the bulk of the seabed base structure 202. The longitudinal and transverse beams of the illustrative beam structure 212 form open rectangular compartments; these compartments may be closed at their lower ends by a nether slab or the compartments may be open downwards. The upper edges of said longitudinal and transverse beams or wails are typically submerged when the seabed base structure 202 is resting atop the pilings, and thus may serve as a supporting, strengthening structure for a module (e.g., a reactor module: not depicted in FIG. 2) that can be docked in the seabed base structure 202, i.e., floated between the upwards-extending wall structures 214, 214 ^f , 214" and over the submerged beam structure 212, then ballasted down to rest on the upper surface of the bea structure 212.

[0085] The seabed base structure 202 is intended to be placed on or just above the seabed 108, supported and affixed by a number of permanent pilings (not shown in FIG. 2) driven through the beam structure 212 as the latter is held in position by the temporary' pilings portrayed in FIG. 2. The base structure 202 may rest on the seabed, fixed thereto by means of said permanent pilings. As clarified in FIG. 3, there are perforations in the beam structure 212 for receipt of permanent pilings, intended to be driven into the seabed. Also, in various embodiments, the upward extending wall structures 214, 214', 214" have perforations or ducts/sleeves (not depicted in FIG. 2) that accommodate optional and/or additional pilings. The ducts and accessories for receiving the pilings are described in International Patent Application PCT/NO2015/050156 (International PCT Patent Application Publication No. WO

2016/085347), which hereby is incorporated in its entirety by reference.

[0086] FIG. 3 shows schematically in perspective, as seen from below, the illustrative seabed base structure 202 of FIG. 2 As shown, the lower sides of the cantilevered ledges 208, 208' are provided with strong points (e.g., strong point 302) that are configured, designed and dimensioned to receive the upper ends of the temporary pilings depicted in FIG. 2 which will support the seabed base structure 202 at least until a sufficient number of permanent pilings are provided. For example, the strong point 302 is provided with an aperture 304 for

accommodating the upper portion of a temporary piling. As also shown in FIG. 3, the upwards projecting walls 214, 214” (wall 214' of FIG. 2 is not visible in the view of FIG. 3) are interconnected by a beam structure 212 whose beams form upwards open cells without a top or a bottom slab. The beam structure 212 is configured to support a module that may be floated into position and deballasted to rest upon the upper surface of the beam structure 212. Channels or apertures (e.g., aperture 306) are provided in the beams of the beam structure 212 to accommodate permanent pilings. In a typical installation procedure, the piling apertures 306 in the beam structure 212 pass completely through the beam structure 212 and allow permanent pilings to be driven from above, through the beam structure 212, and into the seafloor. In typical embodiments, the number of permanent pilings will be greater than the number of temporary pilings, as the permanent pilings must support not only the weight of the seabed base structure 202 but also that of a module (e.g., reactor module) installed thereupon, and must enable the combined structure to withstand all plausible force loads (from, e.g., hurricane winds, rogue waves, tsunamis) with an acceptable margin of safety. In various embodiments, apertures for permanent pilings are also provided in the cantilevered ledges 208, 208’, enabling a greater number of permanent pilings to be employed than could be accommodated by the beam structure 212 alone. Of note,“temporary” pilings are not necessarily removed upon the installation of permanent pilings, but are in some embodiments allowed to remain; they are termed“temporary” herein because the reliance of the seabed base structure upon them for stability is temporary', being superseded for the most part by reliance upon the permanent pilings.

[0087] FIG, 4 shows schematically in perspective the seabed base structure 202 of FIG, 2 and FIG. 3 positioned and supported by temporary pilings (e.g., piling 402) that are aligned position along at least both sides of the base structure 202. A portion of the water surface 404 is depicted. Permanent pilings (not shown) may now be installed by driving the pilings vertically through the apertures or ducts of the beam structure 212 down into the seabed sufficient depth for stably supporting the base structure 202 and its future loads. Once driven, pilings may be affixed to the seabed base structure 202 by various well-known means, e.g., thole pins, notched insteps, or the like. The base structure 202 may thus be permanently fixed to the seabed by permanent pilings while the base structure 202 is stably held in position and supported by means of the rows of temporary pilings. The number of temporary and permanent pilings used and their position, diameter, and length depend on the weight to be supported and on the seabed soil condition. An advantage of embodiments of the present invention is that the seabed base structure 202, constituting a support for one or more floatable modules, such as a reactor module according to the invention, can not only be installed offshore or near shore but can also be detached from its pilings, floated off them, and be moved to a new location or replaced by another seabed base structure.

[0088] FIG. 5 shows schematically an illustrative installation 500 comprising two seabed base structures 502, 504 that have been installed upon a seabed 506 by a number of permanent pilings (e.g , pil ing 508) driven through the beam structures 510, 512 of the two base structures 502, 504. In an example, the first base structure 510 is intended to accommodate a reactor module and the second base structure is intended to accommodate a power conversion module comprising turbines and generators. Some features, including strong points and temporary pilings, have been omitted for clarity.

[0089] FIG. 6 shows schematically portions of an illustrative seabed base structure 600, including the beam structure 602, of an illustrative embodiment similar to that of FIG. 2. Other components of the base structure 600 have been omitted from FIG. 6 for simplicity. The base structure 600 is founded upon the seabed by means of a number of permanent pilings, e.g., piling 604. Moreover, the base structure 602 has been prepared for receipt of a module (e.g., a reactor module) by the installation of a number of architectural seismic isolators (e.g., isolator 606), here represented in simplified schematic form as buttonlike objects. Seismic isolators similar to those already employed in some architectural settings are contemplated. Once a nuclear power module is floated into place above the beam structure 602, it may be ballasted down upon the isolators and affixed thereto. Alternatively, or additionally, seismic isolators may be placed between the upper ends of the pilings and their points of contact with the beam structure 602.

[0090] FIG. 8 shows schematically portions of an illustrative seabed base structure 700, including the beam structure 702, of an illustrati ve embodiment. Other components of the base structure 700 have been omitted from FIG. 7A and FIG. 7B for simplicity. In FIG. 7A, the base structure 700 is founded upon the seabed by means of a number of permanent pilings, e.g., piling 704, and comprises three upwards projecting walls 706, 708, 710 that together approximate an artificial harbor open on side. In the illustrative structure 700, the walls are of relatively great height and areal extent; this may enable wind or wave to exert excessive forces upon the structure 700, e.g., prior to installation of permanent pilings and/or prior to installation of one or more modules (e.g., a nuclear power module) upon the beam structure 702, whereupon the one or more modules, by their relatively great mass, will tend to stabilize the installation against environmental forces. To reduce such forces to an acceptable range, the vertical walls 706, 708, 710 are in this example equipped with a number of slotted bays or cutouts (e.g., bay 712) some or all of which are, in an initial state of the structure 700, open to passage of wind and wave. After installation of permanent pilings and/or one or more modules, the slotted cutouts are filled by the insertion from above of fitted sheets (e.g , sheet 714, shown in a state of partial insertion), which then defend the interior of the seabed base structure 700 from the lateral acti on of wind and wave.

[0091] FIG, 7B depicts schematically the base structure 700 comprising upward projecting walls 706, 708, 710 as a floating embodiment moored to the seafloor by mooring lines 716. This illustrative floating embodiment provides complete isolation from seismic events.

[0092] FIG, 8A depicts schematically aspects of a stage in the assembly of an illustrative embodiment 800. In FIG, 8A, only the portions of objects that rise above the waterline are depicted. A floating module (e.g., an aircraft impact protection structure or reactor module) 802 is in the process of being towed or propelled toward the artificial harbor 804 proffered by a seabed base structure 804 that is similar to those shown in previous FIG, 8 and is founded upon the seabed by means of a number of permanent pilings. The module 802 is preferably sized and shaped to occupy some or all of the harbor 804 and floats at a level that permits entry' into the harbor 804 with at least slight clearance above the upper surface of the beam structure of the seabed base structure 806.

[0093] FIG, SB depicts schematically another stage in the assembly of the illustrative embodiment 800 of FIG. 8 A. In FIG, 8B, the module 802 is in the process of being floated into the harbor 804 proffered by the seabed base structure 806.

[0094] FIG. 8C depicts schematically a third stage in the assembly of the illustrative embodiment 800 of FIG. 8A. In FIG. 8C, the module 802 has been fully inserted into the harbor 804 proffered by the seabed base structure 806. In further stages of installation of the module 802, it is ballasted down upon the beam structure of the base structure 806, e.g , by allowing water to enter internal chambers, coming to rest upon seismic isolators or other force- transmitting supports. In another example of ballasting method, the module 802 is ballasted by externally attached pontoons or floats, which may be detached in sections and/or emptied and tilled with water by pumps, changing their specific gravity and raising or lowering the module 802 in a controlled manner. Such external ballasting methods are also used, in various embodiments, for raising and lowering seabed base structures.

[0095] FIG. 9 depicts schematically portions of an illustrative installation 900 according to an embodiment. The installation 900 comprises a seabed base structure 902 that is founded upon the seabed by means of a number of permanent pilings, e.g , piling 904. It also comprises a module 906 that has been installed within the seabed base structure 902 as, for example, by a process similar to that illustrated in FIGS. 8A-8C. In the illustrative installation 900, the module 906 is an aircraft impact shield, e.g., a large box of reinforced concrete. In various embodiments the aircraft impact shield comprises concrete, steel, composite materials, rock or earth, ice, solid foam, and various other materials arranged in layers, ribs, blocks, mixtures, or other configurations that enhance the shield’s ability to absorb or deflect the effects of impact by an aircraft, missile, projectile, explosion, or other threat to nuclear plant integrity. The module 906 having been installed, a sliding, hinged, or otherwise moveable doorway 908 of the module 906 facing toward the open side of the base structure 902 may be opened, as depicted in FIG. 9. As hinged movement of a massive structure requires massive hinge hardware, in various preferred embodiments the door or portions thereof are lifted into and out of place by a crane, slid sideways as guided by tracks or grooves, or slid up or down vertically as guided by tracks, towers, or grooves. Also in various embodiments the door or portions thereof are omitted. As shall be shown in FIG. 10, an additional floatable module may then be installed within the shield module 906 and the opening closed behind the additional module to complete aircraft- impact coverage. Alternatively, the openi ng of the module may be wholly or partly closed and opened by the attachment and detachment of a set of panels rather than the operation of a single door panel. Also, additional permanent and/or openable and closeable openings and

perforations in any or all of the six surfaces of the rectangular-solid-shaped module 906 are comprised by various embodiments. Also, in various embodiments the aircraft impact shield module 906 is shaped otherwise than as depicted in FIG. 9 (e.g., with an arched top), or is delivered to the base structure 902 in two or more floatable portions. These and other variations on the installation 900 and other installations depicted herein, and on the methods of assembly of such installations depicted and discussed, are contemplated and within the scope of the invention. [0096] FIG, 10 shows schematically and in cutaway view portions of an illustrative installation 1000 according to an embodiment. The installation 1000 comprises a seabed base structure 1002 that is founded upon the seabed by means of a number of permanent pilings, e.g., piling 1004. It also comprises an aircraft impact shield module 1006 that has been installed within the seabed base structure 1002, as depicted in FIG. 9. Also, an opening at unobstructed end of the base structure 1002 is open in the state depicted in FIG. 10 and a floatable reactor module 1008 is approaching the opening. The reactor module comprises an SMR 1010 and additional facilities for the extraction of heat energy from the SMR 1010 The floatable reactor module 1008 is preferably inserted wholly within the aircraft impact shield module 1006, after which the opening by which the reactor module 1008 entered is sealed by a section of shield. In various embodiments, the interior of the aircraft shield 1006 is partly flooded during installation of the reactor module 1008, enabling the reactor module 1008 to be fl oated within the shield 1006 and then ballasted down, after which the entry to the shield 1006 is at least partly blocked and its interior pumped out. Note, given the large mass of a typical reactor module or other module, the draft of a typical module may be significantly deeper than that depicted or implied by schematic Figures herein.

[0097] FIG. 11 schematically depicts portions of an illustrative nuclear power generation station 1100 according to an embodiment. The station 1100 comprises two seabed base structures 1102, 1104 supporting two modules 1106, 1108, where one module 1106 is a reactor module and the other 1108 is a power conversion module. Because the modules 1102, 1104 are close to each other, it is straightforward to bridge the gap between them to convey steam from the reactor module 1106 to the power module 1108, condensate and electrical power from the power module 1108 back to the reactor module 1106, and communications, control signals, and human and mechanical traffic in both directions.

[0098] FIG. 12 schematically depicts portions of an illustrative nuclear power generation station 1200 according to an embodiment. The station 1200 comprises two seabed base structures 1202, 1204 supporting two modules 1206, 1208, where one module 1206 is a reactor module and the other 1208 is a power conversion module. The station 1200 also comprises a cooling tower 1210 (also referred to generally as a cooling module) that is stationed upon a number of seabed pilings similar to those supporting the modules 1206, 1208. The illustrative cooling tower 1210 could be constructed in situ but is preferably constructed elsewhere and floated to the site of the station 1200. A prefabricated cooling tower 1210 can be transported to a prepared set of pilings and installed upon pilings using a variety of techniques; in an example, a cooling tower 1210 could be floated upon a temporary' ring-shaped barge comprising two C- shaped major sections from its place of manufacture to a position above the pilings, then ballasted down upon the pilings. After ballasting down, the ring-shaped barge would surround the pilings, whereupon its two C-shaped portions could be detached from each other, towed away from the pilings, deballasted for towage, and preferably re-used. Other methods of installation of a cooling tower module 1210 are also contemplated for various embodiments: in another example, a cooling tow _' er is installed atop a floatable rectangular module similar to the reactor and power modules 1206, 1208 and is docked into a seabed base structure using a procedure similar to that depicted in FIGS. 8A-C.

[0099] Mention is now made of an illustrative passive cooling method that is contemplated for a number of embodiments comprising SMRs. The method is disclosed in US Patent No. 6,795,518 B1 (hereinafter“US 6,795,518 381”),“Integral PWR with Diverse Emergency Cooling and Method of Operating Same,” the disclosure of which is incorporated herein in its entirety by reference. Herein, an“integral” reactor is one whose steam generators are enclosed in the reactor vessel. In the methodology, passive emergency cooling in response to a loss of coolant accident in a pressurized _' ater reactor having an integral reactor pressure vessel incorporating the steam generators and housed in a small high-pressure containment vessel is provided by circulating cooling water through the steam generators and heat exchangers in an external tank to cool the reactor vessel, limiting the pressure in the containment and preferably lowering the pressure in the reactor vessel below that in the containment to induce coolant flow into the reactor vessel and so keep the reactor core covered with water without the addition of makeup water. Water-containing suppression tanks inside the small high-pressure containment structure limit peak blowdown pressure in the containment. Gravity-fed makeup w _' ater can also be supplied from tanks to cool the core. The passive cooling methods of US 6,795,518 Bl are preferred, but not required, for embodiments of the invention.

[00100] FIG. 13 depicts cross-sectionally and schematically portions of an illustrative nuclear power generating station 1300 that incorporates a version of the emergency cooling method. Station 1300 compri ses a reactor module 1302 and a power conversion module 1304, each founded upon the seabed 1306 by means of a seabed base structure 1308, 1310 and a number of permanent pilings (e.g., piling 1312). The two modules 1302, 1304 are close enough to each other so that bridge connections (e.g., bridge connection 1314) can convey steam, condensate, power, and other flows between them. The reactor module 1302 creates high-pressure steam that is conveyed via the bridge connection 1314 to the power conversion module 1304, which comprises one or more turbines and generators, condensers, coolant pumps for the condensers, and other power-conversion machinery. The reactor module 1302 comprises an SMR housed in a reactor pressure vessel 1316, the reactor vessel 1316 is in turn housed within a containment 1318 of the pressure-suppression type (indicated by a heavy black rectangle). That is, the reactor pressure vessel 1316 is surrounded, within the containment 1318, by a dry (air-filled volume) and a wet (water-containing) volume or pressure-suppression pool 1320 In the event of a loss of coolant accident that produce fuel-element damage in the reactor core and high- pressure steam release from the reactor vessel 1316, the released steam encounters the much greater mass of the water of the pool 1320 and is condensed, raising the temperature of the pool but mitigating pressure rise in the containment, with the ultimate goal of preventing

environmental release of radioactive material from the reactor. Additional water in tanks (e.g., tank 1322) housed within the containment can be released under gravity feed to supply coolant to the interior of the reactor. In an example, the containment has walls of reinforced concrete 1.2 meters thick with an 8 mm steel inner liner.

[00101] FIG. 14 schematically portrays portions of the system of 1300 of FIG, 13 in top- down view (horizontal cross-section). The reactor vessel 1316 is contained, along with pressure-suppression mechanisms, inside the containment vessel 1318. Lines 1314 conducts steam from the reactor vessel 1316 to components in the power conversion module 1304 and condensate in the opposite direction. A pipe detour complex 1402 provides for acceptable flexure of the high-pressure steam/condensate lines 1314 in ease of seismic, weather-driven, or other displacements of the reactor module 1302 or other portions of the system 1300.

[00102] Next, a number of Figures depict illustrative embodiments comprising SMRs of various extant designs. These Figures illustrate the feasibility of accommodating a wide variety of SMR designs in embodiments of the invention, including designs not yet extant, and are in no way restrictive of the SMRs or other nuclear reactor types or classes contemplated for inclusion in embodiments of the in venti on. [00103] Mention is now made of the CAREM (Spanish: Central Argentina de Elementos Modidares) reactor, which is illustrative of a class of SMRs that is contemplated for inclusion in a number of embodiments, e.g., some embodiments incorporating the passive cooling system described with reference to FIG. 13 and FIG. 14. The CAREM reactor is an approximately cylindrical integral SMR with 12 symmetrically arranged steam generators inside the reactor vessel.

[00104] FIG. 15 is a schematic side-view depiction of portions of an illustrative CAREM reactor 1500 including portions of its passive cooling system, showing the reactor vessel 1502, the weight-bearing mounting skirt 1504, a number of steam circulation lines (e.g., line 1506), a steam manifold 1508 with which at least some of the steam circulation lines are in fluid communication, and steam lines 1510 in fluid communication with a power generation module (not shown). Also comprised, though not depicted for simplicity, are coolant condensate lines that return from the power generation module to the 12 steam generators within the reactor vessel 1502.

[00105] FIG. 16 is a schematic top-down depiction of portions of the illustrative CAREM reactor 1500 of FIG. 15. Twelve steam lines (e.g., line 1506) are arranged radially around the reactor vessel 1502, corresponding to 12 integral steam generators inside the vessel 1502. Six of the steam lines communicate with a first circular manifold 1602 and the other six lines communicate with a second circular manifold 1604. The manifolds 1602, 1604 communicate via additional lines 1606, 1608 with turbines of a power plant module (not shown). Also comprised, though not depicted for simplicity, are coolant condensate lines that return from the power generation module to the 12 steam generators within the reactor vessel 1502.

[00106] FIG. 17 is a schematic perspective depiction of portions of the illustrative CAREM reactor 1500 of FIG. 15, including portions of an emergency cooling system termed the Second Shutdown System (SSS). In this viewy two circular steam manifolds 1602, 1604 are visible. The SSS comprises two tanks 1702, 1704 containing boronated water, with gravity-feed pipes 1706, 1708 that can supply water to the reactor vessel 1502 without active pumping and pipes 1710, 1712 for return of heated coolant to the tanks 1702, 1704. Also comprised, though not depicted for simplicity, are coolant condensate lines that return from the power generation module to the 12 steam generators within the reactor vessel 1502. A fl exure relief bow 1714 communicates with one manifold 1602 via steam pipe 1606 and with the other manifold 1604 via steam pipe 1608. The flexure relief bow 1714 allows for the accommodation of a greater degree of nondamaging lateral movement of the system 1500 or components thereof, relative to other components (e.g., a power generation module), as well as of thermal expansion and contraction. The two pipes 1606, 1608 merge on the distal side of the flexure relief bow 1714 to form a single pipe 1716 in fluid communication with a power generation module (not shown). In an example, the two tanks 1702, 1704 of the SSS each contain ~1 m ³ of boronated water which can be dropped into the reactor pressure vessel 1502 under the action of gravity in less than 35 minutes. The water acts both as a coolant and as a vehicle for boron, typically used to extinguish nuclear chain reactions. Either tank 1702, 1704 suffices to produce complete extinction of the nuclear chain reaction in the reactor

[00107] FIG. 18 depicts in vertical, cross-sectional, schematic form portions of an illustrative nuclear module 1800 comprising a CAREM-type nuclear reactor 1802 according to an embodiment. FIG. 18 particularly highlights illustrative safety features comprised by the module 1802, which are safety systems designed on the basis of simplicity and reliability and are mainly of the passive type, since these do not need any external power or fluid inputs to operate and thus reduce the number of possible failure modes. Illustrative forms of some safety systems comprised by the module 1800 in various embodiments are as follows;

[00108] First or Fast Shutdown System (FSS) 1804. Each absorbing element within the reactor 1802 is made up of a set of Ag-In-Cd absorbing rods that move as a single unit. In this example, the FSS comprises 25 absorbing elements (not separately depicted in FIG. 18) that can be dropped into the core by the action of gravity to produce immediate extincti on of the nuclear chain reaction therein.

[00109] Second Shutdown System (SSS) 1806, Portions of an illustrative SSS has already been depicted in FIG. 17. The SSS 1806 provides gravity-pressurized emergency boron injection. When the SSS 1806 is triggered, two tanks, each with ~1 m ³ capacity, drop borated water into the pressure vessel of reactor 1802 by the action of gravity in less than 35 minutes. Although the SSS 1806 is a backup for the FSS 1804, each tank is able to produce by itself the complete extinction of the reactor. For simplicity, only one SSS tank is depicted in FIG. 18.

[00110] Pressure Relief Valves (PR V) 1808. Two PR Vs are included, e.g., valve 1808; only one valve depicted, for simplicity. Each PRV 1808 is in line with a pipe of the SSS 1806 that is in fluid communication with the pressure vessel of reactor 1802. A PRY 1808 may be constructed to open in a passive (unpowered) manner when the temperature difference between its interior and exterior surpasses a certain threshold, or when the PRV 1808 is commanded to open by a control system, or under either condition. Each PRV 1808 is separately capable of passing sufficient coolant flow and thus pressure relief to protect the mechanical integrity of the reactor pressure vessel 1802 against overpressure ari sing from, for example, imbalance between power generated in the core and power extracted from the core by the heat-removal system (steam circulation system).

[00111] Passive Decay Heat Removal System (PHRS) 1810. The PHRS is a heat-removal device designed to reduce the pressure on the primary coolant system and to remove radioactive decay heat in case of a loss-of-heat-sink accident by condensing steam from the primary system in emergency condensers. The emergency condensers of the PHRS 1810 are heat exchangers consisting of an arrangement of parall el horizontal U tubes between two common headers. The top header is connected to the steam dome of reactor 1802 and the lower header is connected to the reactor 1802 at a position below the water level (e.g., at the bottom). Features of the PHRS 1810 are described as follows, though not all are separately and particularly depicted in FIG.

18: The condensers are located in a pool filled with cold water inside the containment building and are, in a non-triggered state, cold and filled with water. The inlet valves in the PHRS steam line (from the top of the reactor 1802) are always open, while the outlet valves are normally closed. When the PHRS 1810 is triggered, the outlet valves open automatically. The water drains from the tubes and steam from the primary system enters the tube bundles and condenses on the cold inner surfaces of the PHRS’s tubes. The resulting condensate returns to the reactor 1802, closing a natural circulation circuit. During the condensation process, heat is transferred from the condenser tubes to the water of the pool. Evaporated pool water is then condensed in the suppression pool of the containment (to be described further hereinbelow).

[00112] Emergency injection system (EIS) 1812. The low-pressure EIS 1812 prevents core exposure in case of a loss-of-coolant accident (LOCA). Following the initiation of a LOCA, the primary system is depressurized and, given participation of the passive heat removal system and/or the boron injection system, pressure inside the reactor 1802 goes down to less than 1.5 MPa with the core fully covered. At 1.5 MPa, the low-pressure EIS 1812 comes into operation. The system consists of two borated water tanks (not separately depicted in FIG. 18) connected to the RPV. In the event of a LOCA, tank pressure of 2.8 MPa produces the breakup of a 1.5 MPa pressure seal, flooding the pressure vessel of the reactor 1802 The system provides 36 hours of protection to the core

[00113] Containment System 1814. This is of the pressure suppression type. A sealed containment structure 1814 (indicated by heavy black rectangle) surrounding the reactor 1802 comprises both a dry (air-filled) enclosed volume and a wet (water-filled) volume, the latter being the pressure suppression pool (PSP 1816, stippled area in FIG. 18). Leaks in the primary system produce a pressure rise in the dry volume, which forces vapor into the PSP 1816, where it is condensed, producing a temperature rise in the PSP 1816 In case of a LOCA with fuel element damage, a high portion of fission products are retained in the PSP 1816, which in an example is built with 1 2 m thick walls made of reinforced concrete with an 8 mm steel liner [00114] Any or all of the foregoing safety systems, as well as others not depicted or described herein, are comprised by various embodiments in association with either CAREM-type SMRs or other types of SMR.

[00115] Mention is now made of the NuScale SMR, an integral pressurized water reactor with internal passive coolant circulation that is illustrative of a class of SMRs that is contemplated for inclusion in a number of embodiments, e.g., some embodiments incorporating the passive cooling system described with reference to FIG. 13 and FIG. 14 The NuScale reactor is an approximately cylindrical integral SMR.

[00116] FIG. 19 depicts in vertical, cross-sectional, schematic form portions of an illustrative nuclear module 1900 comprising four Nu Scale-type reactors (two of which are clearly visible in this cross-sectional view, i.e a first reactor 1902 and a second reactor 1904) according to an embodiment. The four SMRs are housed in a reactor module 1906 that is protected by an aircraft impact shield 1908, both modules being supported by a seabed base structure 1910 that is founded upon the seabed 1912 by means of a number of permanent pilings (e.g., piling 1914). The reactor module 1906, shield 1908, and base structure 1910 have preferably been delivered to the site by means of flotation and stepwise assembly similar to those described hereinabove. The four SMRs are housed in a flooded reactor hall, pool, or gallery', as shall be made clear with reference to FIG. 20, which communicates with a flooded handling pool 1916 through an opening that can be sealed off by a door 1918.

[00117] FIG. 20 depicts in horizontal, cross-sectional, schematic form portions of the illustrative nuclear module 1900 of FIG. 19. The four SMRs 1902, 1904, 2002, 2004 are housed in a flooded reactor hall, pool, or gallery 2006 that is divided into single-SMR compartments by bulkheads (e.g., bulkhead 2008) that can be isolated or placed into

communication by moveable doors (e.g., door 2010). The reactor hall 2006 can be isolated or placed into communication with a flooded handling pool 1916 by moveable doors 1918. The reactor module 1906 also contains an overhead crane system, not depicted, comprising a crane of the trolley-crossbeam type, capable of moving the SMRs and components thereof (e.g., pressure vessel heads) about in at least a portion of the flooded reactor hall 2006 and the handling pool 1916 The module 1906 also comprises various devices and provisions not depicted, e.g. for controlling operations, exchanging fuel and/or SMRs with ships or other outside facilities, moving fuel assemblies internally, laying down and standing up SMRs, extracting fuel from SMRs and inserting fuel thereinto, and the like. The module 1906 comprises a flooded spent-fuel storage area 2012 In various embodiments, the number of SMRs comprised is greater than or equal to 1.

[00118] FIG. 21 depicts in horizontal, cross-sectional, schematic for portions of an illustrative power conversion module 2100 comprising four NuScale-type SMRs 2102, 2104, 2106, 2108. Provisions comprised by power conversion module 2100 for a flooded reactor pool, handling pool, waste storage pool, and other devices pertaining to handling SMRs and fuel are similar to those already portrayed and described for nuclear module 1900 of FIG. 19. The illustrative power conversion module 2100, however, in addition to all these features, comprises four turbine-generator units 2110, 2112, 2114, 2116, each of which exchanges steam and condensate with one of the four SMRs 2102, 2104, 2106, 2108 via corresponding piped circuits 2118, 2120, 2122, 2124 and generates power. In contrast, the nuclear module 1900 of FIG. 19 exchange steam and condensate with one or more turbine-generator units housed in a separate power module. In various embodiments, a power conversion module comprises any number of turbine-generator units greater than or equal to 1.

[00119] Mention is now made of the Rolls Royce or United Kingdom (UK) SMR, another SMR that is illustrative of a class of SMRs contemplated for inclusion in a number of embodiments, e.g , some embodiments incorporating the passive cooling system described with reference to FIG. 13 and FIG. 14. The UK SMR is a three-loop, close-coupled pressurized water reactor (PWR) providing a power output of 450 MWe from 1200-1350 MWth using industry standard UO2 fuel. Coolant is circulated via three centrifugal reactor coolant pumps to three corresponding vertical u-tube steam generators. The design includes multiple active and passive safety systems, each with substantial internal redundancy.

[00120] FIG. 22A depicts schematically in side view portions of a UK SMR 2200 SMR

2200 comprises three vertical u-tube steam generators, two of which 2202, 2204 are visible in the view of FIG, 22A. Pressurized hot water is conducted to each steam generator from the reactor pressure vessel 2206 by piping, and cool water is pumped from each steam generator back into the pressure vessel 2206 via additional piping and a dedicated pump: e.g., hot water is conducted from the pressure vessel 2206 via piping 2208 to steam generator 2204, and cool water is returned to the pressure vessel 2206 via a pump 2210 and piping 2212. Steam from the three steam generators is conducted via piping (not shown) to one or more turbine-generators (not shown) to generate electricity. Moreover, a pressurizer 2214 is connected via piping 2216 to the reactor coolant system pipework hot leg. Primary circuit pressure is controlled by use of electrical heaters located at the base of the pressurizer 2214 and spray from a nozzle located at the top of the pressuri zer 2214. Steam and water are maintained in equilibrium to provide the necessary overpressure. The pressurizer 2214 is a vertical, cylindrical vessel with top and bottom heads constructed of low' alloy steel. The UK SMR 2200 employs surge-induced spray whereby primary coolant passively expands into the spray line causing spray. This provides a simple and safe configuration. The pressurizer 2214 is sized to provide robust and passive fault response for bounding faults, with accidents causing either rapid and significant cooldown or heat-up accommodated. The reactor pressure vessel 2206 is surmounted by a control rod drive mechanism 2218.

[00121] The steam generators of UK SMR 2200 are located asymmetrically around the reactor pressure vessel 2206 so that access is provided to support removal and movement of the reactor pressure vessel head and internals to storage locations within the containment boundary in support of refueling operations. The reactor coolant system uses pumped forced flow at power, but is also configured to provide natural circulation flow for passive decay heat removal, by virtue of steam-generator elevation above the reactor pressure vessel 2206, which ensures a robust thermal driving head between the thermal centers of the core and the steam generators.

[00122] FIG. 22B depicts the UK SMR 2200 of FIG. 22A from a top-down perspective. Visible are three steam generators 2202, 2204, 2220, the reactor pressure vessel 2206, the control rod drive mechanism 2218, and the pressurizer 2214. The piping 2216 that connects the pressurizer 2214 to the pipework hot leg 2222 is depicted.

[00123] FIG. 23 depicts in vertical, cross-sectional, schematic form portions of an illustrative nuclear module 2300 comprising a single UK SMR 2302 according to an embodiment. The SMR is housed in a reactor module 2304 that is protected by an aircraft impact shield 2306, both modules being supported by a seabed base structure 2308 that is founded upon the seabed by means of a number of permanent pilings (e.g., piling 2310). The SMR 2302 is housed within a sealed containment structure 2312.

[00124] Mention is now made of the System Integrated Modular Advanced Reactor

(SMART), a small integral PWR with a rated power of 330 MWth or 100 MWe. To enhance safety and reliability, the design configuration has incorporated inherent safety features and passive safety systems. The design ai is to achieve improvement in the economics through system simplification, component modularization, reduction of construction time and high plant availability. By introducing a passive residual heat removal system and an advanced mitigation system for loss of coolant accidents, significant safety enhancement can be expected.

[00125] FIG. 24 depicts in vertical, cross-sectional, schematic form portions of an illustrative nuclear module 2400 comprising a single SMART SMR 2402 according to an embodiment.

The SMR is housed in a reactor module 2404 that is protected by an aircraft impact shield 2406, both modules being supported by a seabed base structure 2408 that is founded upon the seabed by means of a number of permanent pilings (e.g., piling 2410). The SMR 2402 is housed within a sealed containment structure 2412 (indicated by heavy black rectangle) that comprises both a dry (air-filled) enclosed volume and a wet (water-filled) volume, the latter being the pressure suppression pool (2414, stippled area in FIG. 24)

[00126] Mention is now made of the mPower SMR, an integral P WR designed by Generation mPower and its affiliates Babcock & Wilcox mPower, Inc. and Bechtel Power Corporation, to generate a nominal output of 180 MWe per module. Aspects of the mPower-type SMR have been disclosed in, for example, U.S. Patent No. 9,343,187,“COMPACT NUCLEAR

REACTOR WITH INTEGRAL STEAM GENERATOR,” the entire disclosure of which is incorporated herein by reference. In a standard plant design, each mPower plant is comprised of two mPower units, generating a nominal 360 MWe. The design adopts internal steam supply system components, once-through steam generators, pressurizer, in-vessel control rod drive mechanisms, and horizontally mounted canned motor pumps for its primary cooling circuit and passive safety systems. The mPower SMR uses eight internal integrated coolant pumps with external motors to drive primary coolant through the core. The steam generator assemblies are located within the annular space formed by the inner reactor pressure vessel w-alls and the riser surrounding and extending upward from the core. The control rod drive mechanism design is fully submerged in the primary coolant within the reactor pressure vessel boundary, excluding the possibility of control rod ejections accident scenarios. Reactivity control of the mPower SMR is achieved through the electro-mechanical actuation of control rods only (i.e., no soluble boron).

[00127] FIG, 25 depicts in vertical, cross-sectional, schematic form portions of an illustrative nuclear module 2500 comprising a single mPower SMR 2502 according to an embodiment. The SMR is housed in a reactor module 2504 that is protected by an aircraft impact shield 2506, both modules being supported by a seabed base structure 2508 that is founded upon the seabed by means of a number of permanent pilings (e.g., piling 2510). The SMR 2502 is housed within a sealed containment structure 2512 (indicated by heavy black rectangle) that comprises both a dry (air-filled) enclosed volume and a wet (water-filled) volume, the latter being the pressure suppression pool (2514, stippled area in FIG. 25).

[00128] The foregoing examples of embodiments comprising specific SMR designs are illustrative. It is emphasized that any nuclear reactor capable of being physically supported by- modules delivered by flotation and installed by means of pilings upon a seabed, artificial or natural, is contemplated and within the scope of the invention. Three additional illustrative classes or types of nuclear reactor that are comprised by embodiments are as follows:

[00129] 1) Sodium cooled fast reactors. A sodium cooled fast reactor comprises a reactor vessel in which a liquid metal coolant is accommodated, a core disposed substantially a lower central portion of the reactor vessel in an installed state, a core support structure secured to the reactor vessel for supporting the core, the core support structure dividing an interior of the reactor vessel into a high-pressure plenum below the core and a low-pressure plenum above the high pressure plenum, a circulation pump unit for applying a discharge pressure to the liquid metal coolant and circulating the same, and an intermediate heat exchanger for performing a heat exchanging operation of the coolant in the reactor vessel. The circulation pump unit is composed of an electromagnetic circulation pump provided with a discharge port and a closed gas space, which is filled up with a closed gas, defined above and communicated with the discharge port. The discharge port is also communicated with the high-pressure plenum, wherein the liquid metal coolant above the discharge port flows into the high-pressure plenum by the discharge gas pressure of the gas accumulated in the closed gas space by the actuation of the electromagnetic circulation pump at a time of trip thereof. Sodium cooled fast reactors have been disclosed in the prior art, as for example in U.S. Patent o. 5,265,136,“SODIUM-COOLED FAST REACTOR”; U.S Patent No 9,093,182 B2,“FAST REACTOR”; and U.S. Patent No 5,190,720,“LIQUID METAL COOLED NUCLEAR REACTOR PLANT SYSTEM,” the disclosures of all of which are incorporated herein by reference in their entireties.

[00130] 2) Lead Cooled Reactors. Lead-cooled Fast Reactors (LFRs) feature a fast neutron spectrum, high-temperature operation, and cooling by either molten lead or lead-bismuth eutectic (LBE), both of which support low-pressure operation, have very good thermodynamic properties, and are relatively inert with regard to interaction with air or water. The LFR has excellent materials management capabilities since it operates in the fast-neutron spectrum and uses a closed fuel cycle for efficient conversion of fertile uranium. It can also be used as a burner to consume actinides from spent light water reactor (LWR) fuel and as a burner/breeder with thorium matrices. An important feature of the LFR is the enhanced safety that results from the choice of molten lead as a relatively inert and low-pressure coolant. In terms of

sustainability, lead is abundant and hence available, even in case of deployment of a large number of reactors. More importantly, as with other fast systems, fuel sustainability is greatly enhanced by the conversion capabilities of the LFR fuel cycle. Because they incorporate a liquid coolant with a very high margin to boiling and benign interaction with air or water, LFR concepts offer substantial potential in terms of safety, design simplification, proliferation resistance and the resulting economic performance. Molten lead has the advantage of allowing operation of the primary system at atmospheric pressure. Despite the high density of lead, the pressure loss can be kept relatively low (about one bar across the core for a total of about 1.5 bar across the whole primary _' ^· system) because low neutron energy _' losses in lead allow for a larger fuel-rods pitch. This provides for significant natural circulation of the primary coolant, which results in a suitable grace time for operation and simplification of control and protection systems. The use of a coolant (lead) that is chemically inert with air and water and operating at atmospheric pressure greatly enhances physical protection. [00131] Corrosion of structural materials in lead is one of the main issues for the design of LFRs; therefore, a large effort has been dedicated to short/medium term corrosion experiments in both stagnant and flowing LBE. Few experiments have been carried out in pure Pb, resulting in a lack of knowledge, particularly on medium/long term corrosion behavior in flowing lead. The use of multilayer metal composite materials on reactor components (e.g., fuel assemblies) to prevent corrosion is being investigated. The use of such materials has been described in, for example, U.S. Patent Application Publication No. 2017/0159186A1,“MULTILAYER

COMPOSITE FUEL CLAD SYSTEM WITH HIGH TEMPERATURE HERMETIC IT Y AND

ACCIDENT TOLERANCE,” the entire content of which is incorporated herein by reference. Multilayer metal composites can (a) minimize or prevent buildup of unidentified deposits and hydrogen pickup, which in turn will increase the lifetime, stability, and power density of the fuel, (b) improve hardness to prevent grid-to-rod fretting, which occurs when the spacer gild (a metal piece which separates the fuel rods) and the rods themselves vibrate and wear holes into the metal, and (e) maximize critical heat flux (pertaining to the thermal limit of a phenomenon where a phase change occurs during heating) to improve heat transfer. Another response to the corrosion problem is the use of single-alloy, corrosion-resistant steel for components exposed to liquid lead, as disclosed, for example, in European Patent No. 3 194 633 - Al,“A STEEL FOR A LEAD COOLED REACTOR,” the entire content of which is incorporated herein by reference.

[00132] 3) Heat-pipe cooled reactors. Heat pipes are often proposed as cooling system components for small fission reactors. For example, SAFE-300, STAR-C, and e Vinci are reactor concepts that use heat pipes as an integral part of the cooling system. The core is built around a solid steel monolith with channels for both heat pipes and fuel pellets. Each fuel pin in the core is adjacent to heat pipes for efficiency and redundancy. The large number of in-core heat pipes is intended to increase system reliability and safety. Decay heat also can be removed by the heat pipes with the decay heat exchanger. Liquid metal heat pipe technology is mature and robust with a large experimental test database to support implementation of the technology into commercial nuclear applications. Use of the heat pipes in a reactor system addresses some of the most difficult reactor safety issues and reliability concerns present in current Generation II and III (and to some extent, Generation IV concept) commercial nuclear reactors, in particular, loss of primary' coolant. Heat pipes operate in a passive mode at relatively low pressures, less than an atmosphere. Each individual heat pipe contains only a small amount of working fluid, which is fully encapsulated in a sealed steel pipe. There is no primary cooling loop, hence no mechanical pumps, valves, or large-diameter primary' loop piping typically found in all commercial reactors today. Heat pipes simply transport heat from the in-core evaporator section to the ex-core condenser in continuous isothermal vapor/liquid internal flow. Heat pipes offer distinctive approach to remove heat from a reactor core. Such techniques have been disclosed in, for example, EI.S. Patent Application Publication No. 2016/0027536A1,“MOBILE HEAT PIPE COOLED FAST REACTOR SYSTEM,” the entire content of which is incorporated herein by reference.

[00133] The foregoing illustrated embodiments have all comprised SMRs installed above the waterline upon seabed base structures. Installing SMRs below _' the waterline is accomplished in some embodiments of the invention, and can have certain advantages, as shall be clarified with reference to the next few Figures.

[00134] FIG. 26 depicts schematically portions of two illustrative seabed base structures 2602, 2604 founded upon a seabed by a number of permanent pilings, e.g. piling 2606. The beam structure 2608 of the first base structure 2602 features a central opening 2610 that extends down to the seabed (i.e., there are no pilings or other obstructions beneath the opening 2610). In a typical pow _' er generating station of this type, the first base structure 2602 houses a reactor module and the second base structure 2604 houses a power conversion module. As shall be shown below _' , the opening 2610 in the first seabed structure allows the below-waterline installation of an SMR that is first floated to its installation site in the artificial harbor proffered by the base structure 2602.

[00135] FIG. 27A depicts cross-sectionally and schematically portions of an illustrative seabed assembly 2700 that comprises a single UK SMR 2702 according to an embodiment and that is capable of installing the SMR 2702 below _' waterline. The SMR is housed in a reactor module 2704 that is protected by an aircraft impact shield 2706, both modules being supported by a seabed base structure 2708 that is founded upon the seabed (not depicted) by means of a number of permanent pilings (e.g., piling 2710). The seabed base structure 2708 comprises a central opening or lacuna 2712 similar to the opening 2610 in FIG. 26. The SMR 2702 is housed within a reactor containment structure 2714 that is in turn housed within an

approximately bucket-shaped reactor platform 2716 (crosshatched area). The reactor platform 2716 is upheld by four jack shoes (e.g., jack shoe 2718) which embrace and can be raised and lowered upon four jackets (a.k.a. towers or columns), e.g., jacket 2720. Four jack shoes and four jackets are comprised in this embodiment but only two of each are depicted in the cross- sectional view of FIG. 27A. The reactor module 2704 also comprises an overhead crane 2722 that is capable of moving loads vertically and horizontally within at least a portion of the module 2704, e.g., removing a lid or head 2724 from the containment 2714. Also, the containment 2714 rests, within the reactor platform 2716, upon a reactor support 2726 which may comprise seismic isolators (not depicted in FIG. 27.4) The jack shoes of the reactor platform 2714 can be raised or lowered upon the jackets by various mechanical methods well- known to persons familiar with the art of offshore jack-up rigs. A seabed cavity 2728 is prepared to receive some portion of the reactor platform 2714 in its fully jacked-down state, and may comprise a durable (e.g., reinforced concrete) walls and floor.

[00136] In the state of operation depicted in FIG. 27A, the reactor platform 2716 with its contents is at an initial Up position where the bottom of the reactor platform 2716 is

approximately on a level with the upper surface of the seabed base structure 2708. If, for example, the nuclear module 2704 is delivered (complete with major interior components as depicted in FIG. 27A) by flotation to the seabed base structure 2708 as described with reference to FIGS. 8A, SB, 8C, then the reactor platform 2716 will perforce be in the Up position to enable flotation of the nuclear module 2704 into the artificial harbor proffered by the seabed base structure 270S.

[00137] FIG. 27B depicts the seabed assembly 2700 of FIG, 27A in a second station of operation wherein the reactor platform 2716 has been lowered through the opening 2712, e.g., by ratcheting the jack shoes of the platform 2716 down upon the jackets. The platform 2716 is, here, ballasted sufficiently so that it sinks of its own accord into the water.

[00138] FIG. 27C depicts in cross-sectional perspective view portions of the seabed assembly of FIG. 27A in a third station of operation wherein the reactor platform 2716 has been lowered through the opening 2718 of Fig. 27A to a lowest position. As depicted, the bottom of the reactor platform 2716 is in fact below seabed grade 2730, that is, the platform 2716 has been lowered into the prepared seafloor cavity 2728 of FIG. 27A. In the position depicted, the reactor 2702 is entirely below the waterline 2728 and seabed grade 2730 and is thus shielded by the sea and seabed as well as by the bulk of the nuclear module 2704 and aircraft impact shield 2706. This is advantageous because, in accord with safety regulations, a reactor so shielded typically does not require as massive (and thus as expensive) an aircraft impact shield 2706 as a reactor not so shielded.

[00139] FIG. 28 depicts schematically and in cross-section portions of an illustrative seabed assembly 2800 similar to the seabed assembly 2700 of FIGS. 27A but housing an mPower SMR reactor 2802 rather than a UK SMR reactor. The reactor vessel 2804 is depicted in a fully jacked-down state that places it within a prepared foundation 2806 that is below seabed grade 2808. The reactor 2802 itself is, in this illustrative setting, wholly below waterline 2810 and partly below seabed grade 2808, and thus derives impact shielding from its environment.

[00140] Mention is now made of the Integrated Modular Water Reactor (IMR), a medium sized power reactor with a reference output of 1000 MWth and 350 MWe. This integral primary system reactor employs the hybrid heat transport system, which is a natural circulation system under bubbly flow conditions for primary heat transportation, and avoids penetrations in the primary cooling system by adopting the in-vessel control rod drive mechanism. These design features allow the elimination of the emergency core cooling system.

[00141] FIG. 29 depicts schematically and in cross-section portions of an illustrative seabed assembly 2900 similar to the seabed assembly 2700 of FIGS. 27A-27G but housing an IMR- type reactor 2902 rather than a UK SMR-type reactor. The reactor vessel 2904 is depicted in a fully jacked-down state that places it within a prepared foundation 2906 that is below seabed grade 2908. The reactor 2902 itself is, in this illustrative setting, wholly below' waterline 2910 and seabed grade 2908, and thus derives impact shielding from its environment.

[00142] FIG. 30 depicts schematically and in cross-section portions of an illustrative power generating station 3000 according to an embodiment. The station 3000 comprises two seabed assemblies 3002, 3004, the first 3002 comprising a power plant module and the second 3004 comprising a power conversion module. The assemblies 3002, 3004 are stationed in an artificially dredged channel 3006, e.g., an extension into a shoreline of a natural body of water. The channel 3006 comprises a sub-channel 3008 dredged to a deeper depth. The assembly 3002 comprising a power plant module is stationed in the deeper sub-channel 3008: this has the affect of placing the reactor 3010 entirely below the waterline 3012, enabling the reactor 3010 to derives aircraft impact shielding from its environment and so tending to reduce cost and weight of the aircraft impact shield 3014. In various other embodiments, the functions of the power conversion module here housed in the second seabed assembly 3004 can be performed by a land-based installation adjacent to the channel 3006. Of note, seabed material dredged in the construction of a channel 3006 and/or sub-channel 3008, or earth material from some other source, can be piled upon land adjacent to the channel 3006 to create raised terrestrial barriers and/or used to construct party or wholly submerged in-water barriers in the channel 3006 and/or sub-channel 3008. Terrestrial barriers can confer additional aircraft impact protection and in water barriers can reduce the security threat posed by deep-draft vessels that might deliberately or inadvertently approach the seabed assemblies 3002, 3004.

[00143] FIG, 31 is a schematic depiction of portions of an illustrative power generating station 3100 according to an embodiment. The station 3100 comprises a first seabed assembly 3102 comprising a first reactor module, a second seabed assembly 3104 comprising a first power plant module, a third seabed assembly 3106 comprising a second reactor module, and a fourth seabed assembly 3108 comprising a second power plant module. The modules are linked by utility bridges 3110, 3112, and 3114, which enable to the conveyance of steam, condensate, power, and other materials or substances between the seabed assemblies. The assemblies are founded upon a seabed by means of pilings as shown herein in various Figures, although water, seabed, and pilings are not indicated in FIG. 31 for simplicity. The station 3100 illustrates that various embodiments comprise multiple seabed assemblies performing a variety of functions (not restricted to steam generation and energy conversion).

[00144] Mention is now' made of geoengineering techniques for site preparation for the installation of power generating stations according to embodiments of the invention. Stable proximate environments of adequate size are required for the safe and durable installation of seabed assemblies according to embodiments. To achieve stability and safety, geoengineering techniques may be employed in modifying natural seabed and shoreline features (e.g., reshaping, stabilizing) or artificial features such as cavern walls or banks of dredged channels. Several relevant techniques are now discussed

[00145] Slope stabilization. On soil-covered slopes, soil is constantly moving downslope due to gravity. Movement can be barely evident or devastatingly rapid. Slope angle, water, climate, and slope material contribute to movement. Slope stability is relevant to the slopes earth and rock-fill dams, slopes of other types of embankments, excavated slopes, and natural slopes in soil and soft rock. Slope stability is typically evaluated by the performance a geology or geotechnical engineering study.

[00146] Steep slope angles are often desirable to maximize the level land at the top or bottom of the slope: e.g., the volume of an artificial channel (and thus the effort required to blast and/or dredge the channel) is minimized by steeper, as opposed to more sloping, channel

embankments. However, slope stability decreases with increasing slope angle. Moreover, water plays a major role in slope failure, as rivers and waves erode the base of slopes and remove support.. Water can also increase the driving force by filling previously empty pore spaces and fractures, adding to the total mass. Increased pore water pressure can also decrease resistance by decreasing the shear strength of the slope material Chemical weathering slowly weakens slope material, reducing its shear strength and thus reducing resisting forces. Where integrity of an embankment is vital or in areas subject to detrimental hydraulic forces, additional embankment protection is often required. In granular soils, soil improvement could be performed to increase slope stability.

[00147] Stabilization can be achieved through slope reinforcement by constructing structural elements (anchors) through the failure plane. Structural elements could consist of conventional piles or drilled shafts, jet grout or soil mix columns, or reinforced rigid inclusions. In general, anchors are slope stabilization and support elements that transfer tension loads using high- strength steel bars or steel strand tendons. For example, the Micropile Slide Stabilization System (MS ³ ) is a slope stability technique that utilizes an array of micropiles sometimes in

combination with anchors. The micropiles act in tension and compression to effectively create an integral, stabilized ground reinforcement system to resist sliding forces in the slope. In another example, soil nailing is a slope stabilization or an earth retention technique using grouted tension-resisting steel elements (nails) that can be designed for permanent or temporary support. Soil nails can also be installed in restricted access sites, existing bluffs or retaining wall, and directly beneath existing structures adjacent to excavations. Care should be exercised when applying the system underneath an existing structure since some slope movement occurs before the nails begin resisting the load. Soil nailing has been used for slope remediation and landslide repair, to provide earth retention for excavations for buildings, plants, parking structures, tunnels, deep cuts, and repair existing retaining walls. In a third example, gabions are an earth-retention technique in which gravity retaining walls are formed using rectangular, interconnected, stone-filled wire baskets. Gabion walls have been used to construct temporary or permanent retaining walls and where slope protection or erosion control is required such as channel linings.

[00148] FIG. 32 depicts schematically in vertical cross section portions of an illustrative application 3200 of the anchor-block slope stabilization technique, which stabilizes a slope or retaining wall 3202 using anchored reaction blocks (e.g. blocks 3204, 3206, 3208). The block layout pattern is typically in rows across the slope or embankment wall; in FIG. 32, three blocks are shown in a vertical row. Initially, anchors 3210, 3212, 3214 are installed at the planned center of each block location, typically drilled at right angles to the slope to be stabilized (as depicted in FIG. 32). Reaction blocks 3204, 3206, 3208 are either precast or cast-in-place around the heads of the anchors 3210, 3212, 3214. Bearing plates (not depicted) are then installed between the blocks and the heads of the anchors 3210, 3212, 3214 and the latter are tensioned against the blocks. The finished anchored reaction blocks 3204, 3206, 3208 resist the movement of the retained wall 3202.

[00149] Mention is now made of various stabilization techniques that apply particularly to bulkheads and piers, that is, to vertical interfaces between water and solid ground, such as might be comprised by the site of power generating station according to embodiments

[00150] Ground improvement techniques such as soil mixing and jet grouting can stabilize soft soils by introducing cementitious binder, for planned or remedial work. Vibro replacement stone columns can be constructed behind bulkheads to density soils to reduce lateral pressures on the bulkhead. Voids behind bulkheads can be filled by jet grouting and cement grouting. Soil loss around pier support piles can be remedied with surgical jet grouting. Tieback anchors can be installed through sheet pile bulkheads to permanent lateral support.

[00151] Bulkheads (here referring to vertical dividing wails between water and solid ground) commonly require remediation due to the need to deepen their dredge line (i.e., height where the seabed surface encounters the bulkhead) to accommodate larger ships or due to deterioration experienced over their service life. Improper bulkhead design may lead to lateral deformation or failure of global or toe stability. Jet grouting erodes the soil with high-velocity fluids and mixes the eroded soil with grout to create in situ cemented geometries of soilcrete (full or partial columns, panels, or bottom seals); it underpins and structurally upgrades existing wharfs or bulkheads. Compaction grouting densities liquefiable soils between sections of bulkhead and anchors. Vibro replacement densifles surrounding liquefiable soils to mitigate lateral spreading. Anchors are steel bars or strands grouted into a predrilled hole to resist lateral and uplift forces; they can be added to increase lateral stability, and existing, corroded anchors can be replaced. Soil mixing stabilizes soils behind bulkheads to greatly reduce earth pressures, and provides stable platforms along bulkheads. Cement grouting, also known as slurry grouting, is the injection of flowabJe particulate grouts into cracks, joints, and/or voids in rock or soil, and creates stabilized, low-permeability masses behind walls to stop soil loss through corroded sheet piles. Secant or tangent piles are columns constructed adjacent (tangent) or overlapping (secant) to form structural or cutoff walls.

[00152] FIG. 33 depicts schematically and in cross-section portions of an illustrative bulkhead-restrained embankment 3300 of a power generating station site according to embodiments. A body of earth material 3302 extends partly over a natural or artificial

(dredged) seafloor 3304, upon which various seabed assemblies (not depicted) may be founded upon pilings, e.g. as depicted hereinabove, and is separated from a sea or other body of water 3306 by a solid panel or bulkhead 3308 that is buttressed by a line of tangent pilings (e.g., piling 3310). The wall formed by the bulkhead 3308 and the tangent pilings is, in this example, stabilized in part by the use of an anchor 3312 embedded in a grout-filled void 3314 in the earth material 3302. Additional techniques, such as soil mixing, are used in various embodiments to create further stability

[00153] The trench remixing and cutting deep wall (TRD) method produces mixed-in-place in-ground walls from in situ soil using a vertical cutter post or ground saw. The post is moved laterally through the ground, mobilizing soil that is mixed with a binding agent and left in place to harden as the saw moves on, forming a continuous vertical barrier. TRD is a relatively quiet, efficient way to construct continuous soil-mix walls from 0.5-1 m thick and up to 55 m long in nearly ail subsurface conditions, from soft organics to cobbles and some rock formations. To prepare a deployment site, TRDs can be used for (1) groundwater cutoff walls, to avert seepage and erosion through levees, dams, and reservoir perimeters, (2) foundation support, to strengthen soft soils beneath structures to increase bearing capacity, (3) pollution control, where a TRD barrier serves as a containment structure for subsurface containments or barriers to protect against migration from off-site sources, e.g prevent communication of water layers, water bodies, (4) earth retention support. In the latter application, after construction, soil may be excavated from part of one side of the TRD wall to enable access to the TRD wall (e.g., for anchor installation) or to shape the earth surface for various purposes.

[00154] FIG. 34 depicts schematically and in cross-section portions of an illustrative power generating station 3400 according to embodiments. A seabed assembly 3402 is founded upon pilings 3404 within a sea or other body of water 3406 that is separated from a mass of earth material 3408 by a solid panel or bulkhead 3410. The bulkhead 3410 is buttressed by grout- firmed anchors 3412. In the mass of earth material is a TRD wall 3414, also buttressed by an anchor structure 3416. Aircraft impact protection for the assembly 3402 is provided by a vertical wall 3418 atop the TRD wall 3414.

[00155] FIG. 35 depicts in schematic top-down view portions of an illustrative power generating station 3500 according to embodiments. This figure introduces elements of illustrative embodiments that couple seabed assemblies installed near shore, or in artificially created seabed inlets, or in otherwise protected artificial settings, with on-shore facilities that include, for example, grids, power conversion (turbine-generator) facilities, administration and security facilities, and other. The environment of station 3500 comprises a landmass 3502, water body 3504, and shoreline 3506 (row of angled line segments) that are part of the coastal environment. An artificial channel 3508 is comprised that is at least during an installation phase of the station 3500 in free liquid communication with the w¾ter body 3504. The channel 3508 is deep enough to enable the movement by flotation of seabed base structures and other modules to positions within the channel 3508, where such structures may be founded upon permanent pilings, e.g., in the manner described hereinabove. At least parts of the

embankments of the channel 3508 are stabilized by walls of secant pilings 3510. Within the channel 3508 are established seabed assemblies, e.g., a first seabed assembly 3512 comprising a reactor module, a second seabed assembly 3514 comprising a power plant module, and a third seabed assembly 3516 comprising an auxiliary' module. The seabed assemblies are preferably linked by utility bridges (not depicted) to enable exchanges of steam, condensate, electricity, and other utilities; also, the station 3500 is preferably linked to an electrical grid (not depicted) on the land mass 3502.

[00156] FIGS. 36A-38 are schematic depictions of portions of illustrative embodiments where the physical layout of the embodiments is emphasized, rather than the functional relationships between components. [00157] FIG, 36A is a schematic, top-down view of portions of another illustrative coastal power generating station 3600 comprising some number of SMRs in reactor modules. FIG.

36A depicts the site prior to the arrival of seabed assemblies housing, e.g., a reactor module and an auxiliary module; FIG. 36B depicts the site after installation of seabed assemblies.

[00158] The power generating station 3600 comprises a !andmass 3602, water body 3604, and shoreline 3606 (row of angled line segments) that are part of the coastal environment. The power generating station 3600 also comprises a dock 3608. The dock 3608 comprises a number of grounded concrete caissons (e.g , caisson 3610) that define a barrier or housing that is closed on the seaward side and open on the shoreward side. Preferably, caissons are floated into place and ballasted to ground on a natural or prepared portion of the seafloor. Moreover, the dock 3608 is preferably constructed in such a way that substantial routine mixing or circulation of water in the dock with water in the surrounding water 3604 is prevented. Various other embodiments omit caissons, relying instead on the structural stability of seabed assemblies to withstand environmental forces.

[00159] A natural or dredged approach channel 3611 constitutes a marine interface for power generating station 3600, being of sufficient breadth and depth to permit delivery of seabed base structures and modules by flotation to a stationing area 3612 optionally floored by a prepared foundation. A relocatable (e.g., floating or easily de-ballasted) caisson 3614 may be moved to constitute part of the dock 3608, closing off the approach channel 3611, e.g., after delivery' of seabed base structures and module to the stationing area 3612. Aircraft impact shielding is incorporated in one or more nuclear modules installed upon seabed base structures. A rail transfer system 3618 connects the dock 3608 to an emergency response facility 3638 and a cask yard 3622, and both interface with a security facility 3620 before further transport onshore, enabling controlled exchange of nuclear and other materials (e.g., dry casks of cooled spent nuclear fuel) between the external on-shore facilities and the dock 3608. A tank yard 3624 houses fluids such as purified water for reactor operations and low-level liquid radioactive waste. A power plant (turbine house) 3626 exchanges heat-transfer fluids (e.g., steam, water) with the nuclear module (depicted in FIG. 36B) via a pipe bundle that terminates in a flange 3630 for quick interfacing of with the nuclear module upon installation of the latter. Flow's of steam and condensate through the pipe bundle 3628 are controlled by valves (not depicted), e.g., shutoff valves at each end of the pipe bundle 3628. The pipe bundle 3628 is supported by a pipe bridge (not shown) and hangers (not shown) that accommodate thermal expansion and contraction. The power plant 3626 converts to electricity a portion of the thermal energy thus delivered, and this electricity is distributed to a grid or other consumers via a switchyard 3634. Also, liquids are also conveyed between the tank yard 3624 and the modules by piping 3636 supported by an additional pipe bridge 3638. Coolant water is collected from the environmental water body 3604 via a coolant intake 3640 from which debris and other harmful objects or materials are excluded by inlet strainers 3642; water from the inlet 3640 is conveyed to the power plant 3626 via inlet piping 3644 and associated pumps (not depicted). Heated coolant from the power plant 3626 is returned via outlet piping 3646 with watertight integrity provided by isolation valves (not depicted) to the w'ater body 3604 via an outlet 3648 that is preferably closer to the shore 3606 than the inlet 3640 and far enough from the inlet 3640 to prevent untoward mixing of heated outlet water with cool inlet water. An Emergency Response Facility 3650 acts as a backup control center for the power generating station 3600 and its associated facilities and may also stage other contingency systems, e.g., rail-mounted or other equipment for responding to emergencies. The Emergency Response Facility 3650 ensures that sufficient coolant is delivered from the tank yard 3624 to the nuclear reactor(s) (e.g., sufficient coolant to support passive convective cooling); also, it enables lower impact protection standards for other control facilities comprised by the deployment 3600, since diversification of control points is functionally interchangeable with heightened hardening of a single control point: either diversification or higher hardening can only be disabled by larger or multiple attacks, which are more difficult to mount and therefore less likely to be mounted.

[00160] The on-shore facilities of the power generating station 3600 are sheltered by a defensive perimeter 3652 that may comprise various barriers, devices, personnel, drones, and the like to defend the power generating station 3600; additional defensive measures may be comprised by the power generating station 3600 to defend against aerial and marine threats. Whether or not named or depicted herein, various such defensive arrangements can be comprised any embodiment of the invention discussed herein as well as by other embodiments.

[00161] FIG, 36B is a schematic, top-down view of portions of the illustrative power generating station 3600 of FIG. 36A after installation of tw ^? o seabed assemblies. In the state of construction of deployment 3600 depicted in FIG. 36B, a first seabed assembly 3654 comprising a nuclear module has been ensconced in the dock 3608 beneath the lengthwise arching portion 3616 of an impact shield. The pipe bundle 3628 and the liquids-transfer pipe 3636 have been connected to modules. The impact-shielded seabed assembly 3654 comprises the nuclear plant (e.g., SMR gallery, control room module, fuel storage module, fuel-handling module). SMRs are preferably installed and removed from the nuclear module via a unshielded auxiliary module 3658, SMRs may arrive and depart via a land route for directness of access to the unshielded modules 3658, being conveyed locally on the rail system 3618, which is supported by a causeway or bridge 3660, or may arrive and depart via flotation through the channel 3611. The moveable caisson 3614 has, after delivery of the seabed assemblies 3654, 3658, been stationed across the channel 3611, reversibly blockading the assemblies 3654, 3658 within the dock 3608.

[00162] An advantage of deployment 3600, as of various other embodiments, some discussed herein, is that all components delivered in a modular fashion may be removed as they were delivered, by flotation, whether for decommissioning at a specialized facility or deployment at a different location, and one or more replacement units may be installed at the power station 3600. Mobility and modularity thus are features of the nuclear power station as a whole: moreover, SMRs are preferably and typically small enough to be removed from the nuclear module, redeployed, decommissioned remotely, and/or replaced in a manner analogous to the nuclear module itself. Thus, advantages are obtained from modularity and mobility both at the station scale and at the scale of the individual small modular reactor.

[00163] Of note, various embodiments comprise features of the power generating station 3600 but depart fro it in many ways. For example, the terrestrial power plant 3626 is in some embodiments replaced by a seabed assembly comprising a power conversion module that is established within the dock 3608. Embodiments comprise multiple channels, multiple nuclear units, multiple power conversion modules, various terrestrial facilities (or none at all), and so forth. All such variations and combinations are contemplated and within the scope of the invention

[00164] FIGS. 37A and 37B are schematic, top-down views of portions of an illustrative power generating station 3700 comprising some number of SMRs (not depicted). FIG. 37A depicts the site prior to the arrival of seabed assemblies; FIG. 37B depicts the site after installation of seabed assemblies. The power generating station 3700 comprises a landmass 3702, water body 3704, and shoreline 3706 that are part of the coastal environment. The power generating station 3700 also comprises a water-filled basin 3708 (i.e., depression cut into the landmass 3702 and in fluid communication with the environmental water body 3704) whose walls are defined and stabilized on at least two sides by rows or barriers of pilings (e.g., barrier 3710). Pilings may be conventionally driven or formed in situ, e.g., of pre-tensioned concrete poured in drilled shafts and/or tubes. Walls of the basin 3708 may be stabilized using any of the methods of geoengineering stabilization discussed hereinabove, or similar methods. The basin 3708 is of sufficient breadth and depth to permit delivery of modules by flotation. A relocatable caisson 3712 may be moved to close off the basin 3708, e.g., after delivery of modules to the basin 3708. Aircraft impact is incorporated in one or more nuclear modules installed upon a seabed base structure. A rail transfer system 3714 connects the area of the basin 3708 to an administration and security facility 3718 onshore, to the emergency response facility 3738, and to a cask yard 3720, enabling controlled exchange of nuclear and other materials (e.g., dry casks of cooled spent nuclear fuel) between the on-shore facilities and the basin 3708. A tank yard 3722 houses fluids such purified water for reactor operations and low- level liquid radioactive waste.

[00165] Two power plants (turbine houses) 3724, 3726 exchange heat-transfer fluids (e.g., steam, condensate) with nuclear modules (depicted in FIG. 37B) via pipe bundles (depicted in FIG. 37B) and convert a portion of the thermal energy thus delivered to electricity that is distributed to a grid or other consumers via switchyards 3728, 3730.

[00166] Coolant water is collected from the environmental water body 3704 via a coolant intake 3732; heated coolant from the power plants 3724, 3726 is returned to the water body 3704 via an outlet 3734 that is preferably closer to the shore 3706 than the inlet 3732 and far enough from the inlet 3732 to prevent untoward mixing of heated outlet water with cool inlet water. Screening and piping for the coolant inlet 3732 and outlet 3734 are not depicted in FIG. 37A or other Figures herein, but are preferably comprised. An Emergency Response Facility 3738 acts as a backup control center for the power generating station 3700 and its associated facilities, much as the Response Facility 3650 of FIG. 36A functions for power generating station 3600. A support deck 3736 supports interface of the rail transfer system 3714 with the edge of the basin 3708.

[00167] FIG. 37B is a schematic, top-down view' of portions of the illustrative coastal power generating station 3700 of FIG. 37A after installation in the basin 3708 of two seabed assemblies 3742, 3744 comprising nuclear modules. Two pipes (e.g., pipe 3746) exchange heat- transfer fluids between the nuclear-module seabed assemblies 3742, 3744 and the two power plants 3724, 3726 Liquids are conveyed between the tank yard 3720 and an auxiliary systems module of the MNP-B 3742 by piping 3752 supported by the support deck 3736 The moveable caisson 3712 has, after delivery of the seabed modules 3742, 3744, been stationed across the basin 3708, reversibly sealing the seabed modules 3742, 3744 into the basin 3708 The rail transfer system 3716 enables exchange of nuclear and other materials (e.g , dry casks of cooled spent nuclear fuel, SMRs) between the onshore facilities and the seabed module 3742, case casks and other loads are exchanged by flotation with the seabed module 3744

[00168] Of note, various embodiments comprise features of the pow'er generating station 3700 but depart from it in many ways. For example, the terrestrial power plants 3724, 3726 are in some embodiments replaced by seabed assemblies comprising a power conversion modules that are established within the basin 3708 or similar, nearby basins. Embodiments comprise multiple basins, multiple nuclear units, multiple power conversion modules, various terrestrial facilities (or none at all), and so forth. All such variations and combinations are contemplated and within the scope of the invention

[00169] FIG. 38 schematically depicts in vertical cross section portions of another illustrative power generating station 3800 according to an embodiment. Station 3800 is exemplary of a class of embodiments that feature the installation of seabed assemblies in highly defensible, natural or artificial settings such as caverns, fjords, canyons, and the like A landmass 3802 has a bold coast adjacent to a water body 3804 A cavern 3806, either natural or artificially excavated by techniques familiar in the fields of mining and tunneling, is open to the water body 3804 extends into the landmass 3802. The floor of the cavern 3806 is sufficiently below the level of w'ater body 3804 to enable the delivery by flotation of seabed base structures and other modules to the interi or of the cavern 3806, where such structures can be installed upon permanent pilings, e.g., as described and depicted hereinabove. The illustrative power generating station 3800 comprises a first seabed assembly 3808 comprising a nuclear module and a second seabed assembly 3810 comprising a pow'er plant module. The roof and walls of the cavern 3806 are stabilized by grouted anchors (e.g., anchor 3812) and/or other

geoengineering means. Power generated by the station 3800 is delivered to a grid or other consumer (not depicted). [00170] Of note, various embodiments comprise features of the power generating station 3800 but depart from it in many ways. For example, various other embodiments comprise multiple caverns or basins within a single cavern, multiple nuclear modules, multiple pow'er conversion modules, various terrestrial facilities (or none at all), modules stationed outside one or more caverns as well as within, and so forth. All such variations and combinations are contemplated and within the scope of the invention.

[00171] FIGS, 39 and 40 are conceptual schematics depicti on of portions of facilities comprised by illustrative pow'er generating stations built according to embodiments of the invention, and of some flows of material and energy between the facilities.

[00172] FIG. 39 depicts portions of an illustrative agro-industrial complex 3900 that comprises one or more modular seabed-based units and includes, minimally, a seabed assembly unit containing a nuclear module or power conversion module. Complex 3900 is designed to realize advantages of locating various productive facilities and energy-consuming activities in the vicinity of a power generating station 3902 that supports a local population center 3904.

The population center 3904 may be an existing conurbation, a temporary' city or work camp, a military' or research base, an artificial offshore or seabed community, city, or offshore metropolitan area, or more than one of the foregoing.

[00173] The nuclear power generating station 3902, in embodiments, comprises both a nuclear module and power conversion module, or more than one of either or both; or, a nuclear module founded upon pilings and a terrestrial power conversion module; or a power conversion module founded upon pilings and a terrestrial nuclear pow'er plant, or various combinations of and variations upon such arrangements, all of which are contemplated and within the invention’s scope. In embodiments, the nuclear power generating station 3902 produces electrical power, thermal energy, or both. Other facilities depicted in FIG. 39, to be enumerated below', are (1) facilities, denoted by plain rectangles, that receive, stage, or produce inputs of the complex 3900, (2) facilities, denoted by capsule-shaped forms, that are typically involved in the transformation or processing of inputs or internal flows of the complex 3900, and (3) facilities, denoted by bold rhombuses, that receive, stage, or produce outputs of the complex 3900

Various facilities comprised by the complex 3900 are, in embodiments, modules (i.e., are manufactured and delivered, preferably by flotation, to the location of complex 3900), non- modular (i.e., are constructed on site), or hybridizations of modular facilities with n on-modular facilities.

[00174] FIG. 39 does not depict systems or facilities (e.g., grids, transportation networks) not comprised by the complex 3900, nor various aspects of the complex 3900 (e.g., defensive systems), nor some aspects of the local environment of the complex 3900. The latter typically compri ses both a landmass, herein termed the“terrestrial environment,” and a relatively large body of water, e.g., lake, river, or ocean (“marine environment”), from which water is drawn by a seawater intake facility 3906. Moreover, non-nuclear sources of energy (e.g., natural gas generators, solar panels) may be comprised by the complex 3900, but none such are depicted in FIG. 39; the primary source of energy in the complex 3900 is preferably the nuclear power generating station 3902.

[00175] Some material inputs to the complex 3900 arrive from (1) a secured receiving facility 3908, which handles the arri val of nuclear fuel for the power generating station 3902, (2) a seawater intake facility 3906 drawing from some body of water which, if an ocean, is a source of water as a coolant, of salt water for freshening, and of useful substances in solution (e.g., CQ2, salt), (3) a raw industrial materials receiving facility _' 3910, and (4) a hydrocarbon receiving facility 3912 (e.g., liquefied natural gas terminal or petroleum receiving facility).

[00176] Materials are altered in form, typically in a manner that adds value for export or makes the materials useful to a local population center, in a number of process facilities, including a desalination plant 3914 producing freshwater and brine, an electrolysis plant 3916 producing purified freshwater, Hb, C , and/or other outputs, an industrial process plant 3918, an agricultural facility 3920, a manufacturing facility 3922, a petrochemical process plant 3924, a facility for treating agricultural, industrial, and urban wastes 3926, and an emergency accommodation facility 3928.

[00177] Material and energy outputs (e.g., products and wastes) of the complex 3900, which may exit the complex 3900 and/or return to other portions thereof, are handled by a dry' cask storage facility 3930, an electrical transmission and distribution facility (a.k.a. substation) 3932, a thermal storage and distribution facility 3934, a products storage, distribution, and export facility 3936, a food packaging, storage, and refrigeration facility 3938, a freshwater storage and distribution facility' 3940, a fuel storage facility 3941, and an agricultural, industrial, and urban waste treatment facility 3926 Some or all of the foregoing plants and facilities except inherently stationary' resources are, in various embodiments, produced and delivered to the complex 3900 as MP units, realizing advantages including those enumerated hereinabove for IP units. Various embodiments omit one or more of the facilities comprised by illustrative complex 3900 and include facilities not comprised by complex 3900.

[00178] Some of the energy forms and materials that flow between elements of the complex 3900 include fresh nuclear fuel 3942; cooled spent nuclear fuel 3944; coolant water 3946;

electrical power 3948 for transmission to the population center 3904 and all other facilities comprised by deployment 3900, thermal energy 3949 delivered to the thermal storage and distribution facility 3934, heat and/or electrical power 3950 for use by the desalination plant 3914; desalinated water (freshwater) 3952 for use by the electrolysis plant 3916; desalinated water 3954 for use by the industrial process plant 3922; desalinated water 3956 for use by the agricultural facility 3920; brine 3958 for use by an industrial process plant 3918; raw industrial materials (e.g., feedstocks) 3960 for use by the industrial process plant 3918; fertilizer 3962 for use by the agricultural facility 3924; industrial products 3964 for handling by the storage and distribution facility 3936; agricultural products 3966 for handling by the food handling facility 3938; hydrocarbons 3968 from the hydrocarbon receiving facility 3912 for processing by the petrochemical plant 3924; petrochemical outputs 3970 (e.g., resins, synthetic fuels) for handling by the storage and distribution facility 3936; petrochemical outputs 3972 for use in the manufacturing facility 3922; electrolysis gases 3960 (e.g., H , O2) for use by the industrial process plant 3918; manufactured products 3976 for use in the population center 3904; wastes 3978 from the population center 3904 for treatment in the waste treatment facility 3926;

processed industrial materials 3980 (e.g., metal, plastics) from the industrial process plant 3918 to the manufacturing facility 3922; organic outputs 3982 from the agricultural production facility 3920 to the petrochemical process plant 3924 (e.g., wastes or crop feedstocks for conversion to synthetic fuel); synthetic or processed fuel 3984 from the petrochemical process plant 3924 to the fuel storage facility 3941; and synthetic or processed fuel 3986 from the fuel storage facility 3941 to the population center 3904. Heat 3988 and power 3990 are delivered to the population center 3904. Of note, electricity, thermal energy, freshwater, purified water, fuels, electrolysis gases, and other materials are typically distributed to many facilities comprised by complex 3900, although only selected transfers are explicitly depicted in FIG. 39. For example, all facilities will receive electricity from the substation 3932, and thermal energy from the thermal storage and distribution facility 3934 may be delivered for district heating, process heat, or the like to various facilities. In another example,“distribution” of products from the product storage, distribution, and export facility 3936 will typically be local (i.e., to other facilities of the complex 3900 and to the population center 3904), e.g., via pipelines or local trucking, while“export” of products will typically entail transfer to relatively remote destinations, e.g., by air, maritime container shipping, or long-haul rail.

[00179] In another example, materials to a population center and processes supportive thereof may be extracted from seawater as a byproduct of desalination 3914, electrolysis 3916, and additional processes. For example, carbonates can be extracted from seawater and converted to oxides for cement manufacture. Also, sea salts (primarily sodium chloride) are a marketable byproduct of desalination, given appropriate quality controls.

[00180] In another example, the power generating station 3902 also supplies power to a facility comprising a data center and/or supercomputing facility 3992 requiring large amount of electricity, where the facility 3992 may be installed offshore, e.g., as a module founded upon the seafloor by means of a seabed base structure as described herein.

[00181] In another example, the power generating station 3902 also supplies power to an offshore or seabed mining facility or operation 3994 requiring large amount of electricity, where the facility 3994 may comprise modules founded upon the seafloor by means of a seabed base structure as described herein.

[00182] FIG. 40 depicts portions of another illustrative complex 4000 comprising one or more nuclear and/or power conversion modules founded established by means of seabed base structures and including, minimally, a nuclear module. Complex 4000 is designed to realize advantages of locating various resource extraction or production facilities and energy- consuming processes related to such extraction in the vicinity of a nuclear power generating station 4002 and one or more extractable natural resources (e.g., coal, gas, or petroleum fields or solid-mineral mines). The nuclear power generating station 4002, in embodiments, comprises both a nuclear module and power conversion module, or more than one of either or both; or, a nuclear module founded upon pilings and a terrestrial power conversion module: or a power conversion module founded upon pilings and a terrestrial nuclear power plant; or various combinations of and variations upon such arrangements, all of which are contemplated and within the invention’s scope. In embodiments, the power generating station 4002 produces electrical power, thermal energy, or both. Other facilities depicted in FIG. 40, to be enumerated below, are (1) various modular or non-modular facilities, denoted by plain rectangles, which receive, stage, or produce inputs of the complex 4000, (2) facilities, denoted by capsule-shaped forms, that are typically involved in the transformation or processing of inputs or internal flows of the complex 4000, and (3) facilities, denoted by bold rhombuses, that receive, stage, or produce outputs of the complex 4000

[00183] FIG. 40 does not depict systems or facilities (e.g., grids, transportation networks) not comprised by the complex 4000, nor various aspects of the complex 4000 (e.g., defensive systems), nor some aspects of the local environment of the complex 4000 The latter typically comprises both a terrestrial environment and a marine environment. The primary' source of energy in the complex 4000 is preferably the power generating station 4002.

[00184] Some material inputs to the complex 4000 arrive from (1) a secured receiving facility 4006, which handles the arri val of nuclear fuel for the power generating station 4002, (2) a seawater intake facility 4004 drawing upon a body of water which is a source of water as a coolant and (if an ocean) of salt water for freshening and of useful substances in solution (e.g., CO?., salt), (3) a fossil fuel resource 4008 (e.g., oil field), and (4) a mineral resource 4010 (e.g., mine).

[00185] Materials are altered in form, often in a value-adding manner, in a number of process facilities, including a desalination plant 4012 producing freshwater and brine, an electrolysis plant 4014 producing purified freshwater, H?, O2 , and/or other outputs, a resource production facility plant 4016, a petrochemical processing plant 4018, a mineral processing plant 4020, a resource production waste treatment facility 4022, a refining process byproduct treatment facility 4024, an environmental monitoring and remediation facility 4026, a dock and/or site construction support facility 4028, and a deployment crew accommodations and logistics facility 4030.

[00186] Material and energy outputs (e.g , products and wastes) of the complex 4000, which may exit the complex 4000 and/or return to other portions thereof, are handled by a dry' cask storage facility 4032, an electrical transmission and distribution facility (a.k.a. substation) 4034, a thermal storage and distribution facility 4036, a product storage, distribution, and export facility 4038, and a freshwater storage and distribution facility 4040. Of note, the resource production facility 4016 performs functions supportive of resource extraction from the fossil fuel resource 4008 and the mineral resource 4010; these functions include the refining of hydrocarbons from the fossil fuel resource 4008 and the separation, concentration, and refining or reducing of minerals from the mineral resource 4010. Some or all of the foregoing plants and facilities, except inherently stationary resources, are, in various embodiments, produced and delivered to the deployment 4000 as modular units established upon seabeds by means of pilings, realizing advantages including those enumerated hereinabove for modular units.

Various embodiments omit one or more of the facilities comprised by illustrative complex 4000 and/or include facilities not comprised by complex 4000.

[00187] Some of the energy forms and materials that flow between elements of the complex 4000 include fresh nuclear fuel 4042; cooled spent nuclear fuel 4044; coolant water 4046; electrical power 4048 for transmission to other facilities comprised by deployment 4000, thermal energy 4050 delivered to the thermal storage and distribution facility 4036; heat and/or electrical power 4052 for use by the desalination plant 4012; desalinated water (freshwater) 4054 for use by the electrolysis plant 4014; desalinated water 4056 for use by the resource production facility 4016; brine 4058 for use by the electrolysis plant 4014, raw fossil fuel resources 4060 for handling by the resource production facility plant 4016; raw mineral resources 4062 for handling by the resource production facility plant 4016; heated fluids 4064 and/or chemical reactants and/or other outputs of the resource production facility 4016, delivered to the fossil fuel resource 4008 to assist in extraction; heated fluids 4066 and other outputs of from the resource production facility 401 , delivered to the mineral resource 4010 to assist in extraction; electrolysis gases (e.g., H?., O2) for use by the petrochemical processing plant 4018, resource production facility 4016, and mineral resource facility 4010; refined hydrocarbons 4070 from the resource production facility 4016 (derived from the fossil fuel resource 4008) for processing by the petrochemical plant 4018, separated, concentrated, and/or refined or reduced minerals or metals 4072 (derived from the mineral resource 4010) from the resource production facility 4016 for processing by the mineral processing plant 4020; directly useful hydrocarbon or mineral outputs 4074 of the resource production facility 4016, delivered to the production storage, distribution, and export facility 4038; petrochemical outputs 4076 (e.g., resins, synthetic fuels) of the petrochemical processing plant 4018 for handling by the storage, distribution, and export facility 4038; and refined metallic or mineral outputs 4078 for handling by the storage, distribution, and export facility 4038. Of note, electricity, thermal energy, freshwater, purified water, fuels, electrolysis gases, minerals (e.g., magnesium) extracted from brine by the electrolysis plant 4014, and other materials are typically distributed to many of the facilities comprised by complex 4000, although only selected movements are explicitly depicted in FIG. 40.

[00188] In another example, the power generating station 4002 also supplies power to a facility comprising a data center and/or supercomputing facility 4080 requiring large amount of electricity, where the facility 4080 may be installed offshore, e.g., as a module founded upon the seafloor by means of a seabed base structure as described herein.

[00189] In another example, the power generating station 4002 also supplies power to a local population center 4082. The population center 4082 may be an existing conurbation, a temporary city or work camp, a military or research base, an artificial offshore or seabed community, city, or offshore metropolitan area, or more than one of the foregoing.

[00190] Of note, in embodiments the storage and distribution facility 4038 enables the export of products from the complex 4000; the secured receiving facility 4006 has safeguards such as secure tracking and reporting to appropriate regulator} authorities as fuel is received, as well as a secure physical fuel-transfer connection to the power generating station 4002; Tk from the electrolysis plant 4014 can also be an input to the petrochemical process plant 4018 (transfer connection not depicted in FIG. 40); and other substances may be variously moved between facilities of complex 4000 for various purposes. The resource production waste treatment facility 4022 copes primarily with wastes from extraction from the mineral resource 4010 and the fossil fuel resource 4008. The refining process byproduct treatment facility 4024 copes primarily with wastes of the mineral processing plant 4020 and petrochemical processing plant 4018, enabling (e.g., by various treatments) such wastes to be recycled, neutralized, and/or sequestered. The environmental monitoring and remediation facility 4016 copes primarily with effluents, leaks, and spills from all the facilities of the complex 4000, whether nuclear or nonradioactive, chronic or emergent, and foreseen or unforeseen.

[00191] In an example of an energy-intensive industrial process benefiting from proximate access to the heat and electrical output of the power generating station 4002, magnesite (MgCCk) to magnesium oxide (MO) and CO2 by the addition of heat, the CO2 being either utilized in a process or persistently sequestered in a carbon capture-and-storage scheme, e.g., one that pumps the CO2 into a saline aquifer at high enough pressure to make the CO2 into a supercritical fluid that dissolves in the saline. Such sequestration will be more economically feasible where the energy inputs to magnesite conversion and sequestration are more economically obtained, as in the complex 4000. The MO thus obtained may be used in the in reduction of other metals from ore, e.g., in Kroll processing of titanium or zirconium carried out by the mineral processing plant 4020. In another example, Bayer processing of bauxite to produce aluminum is well-known as an electricity-intensive process and would benefit by proximity to the power generating station 4002. In another example, process steam from the power generating station 4002 can be used to mobilize high-viscosity fossil fuels (e.g., bitumen) in an unconventional fossil fuel resource 4008 or a conventional reservoir depleted of readily extractable fossil fuel. In another example, magnesium is present as a soluble salt in seawater (-1.3 x 36 ³ kg/liter Mg ²⁺ ions, associated with chloride and sulfate ions), and can be produced as a suitable industrial compound, e.g., magnesia, as a byproduct of the desalination plant 4012.

[00192] Numerous other examples can be adduced of energy-intensi ve processes that would benefit by integration in a complex 4000 or other embodiments, e.g., oxygen liquefaction from air, electric steel and iron production, ferromanganese refinement, and more. All such processes are contemplated.

[00193] V arious modular units comprised by complex 3900 and 4000, including the nuclear power plants, may be located in a littoral, near-shore, or off-shore manner, realizing

environmental and social advantages by minimizing disruption of landmass and coastal environments and human settlement patterns. The complexes 3900 and 4000 can, in an example, serve regions that have growing energy, water and transportation fuel needs, but do not wish or cannot afford to develop the massively expensive infrastructure that is required to produce them indigenously. For various embodiments, initial installation of can be rapid, as floatable modules are transported from shipyards to the site, with minimal site preparation required compared to traditional terrestrial power and water projects. If a worldwide fleet of floatable modules is available, production could be initiated within months as compared to years or decades for conventional development approaches. Capacity and capabilities of the complexes 3900 and 4000 or other embodiments can be modified flexibly during the lifetime of the project by adding or subtracting floatable modules. The customer does not have to commit to a 60-80 year project, and the host country' does not need to own the infrastructure. In an example of the advantages realizable from such deployments, given a nuclear power source, desalinated water and synthetic fuels production occurs with essentially zero direct CO?. emissions.

[00194] Moreover, various industrial and agricultural processes can realize advantages by integration with the nuclear plants in complexes 3900 and 4000, since closer proximity of facilities to the primary energy source and to each other reduces all losses and costs associated with transport of electricity, heat, water, gasses, industrial material, products, and the like.

Pipelines, which tend to be expensive and vulnerable, are reduced by proximity to minimal lengths, enabling the more efficient transfer of liquids (e.g , desalinated water for agriculture and other processes) and gasses (e.g., Eh, notoriously difficult to contain) and the more economic exploitation of heat (the primary energetic output of a nuclear power plant) in, e.g., industrial, agricultural, production, and fuel extraction processes. Transmission losses for electrical power to points of use are also reduced, and shorter electrical transmission lines connecting the nucl ear power plant to various facilities of the complexes 3900 and 4000 are less costly and more reliable than long-haul lines. Security and defense are advantageously realized in complexes 3900 and 4000 by tasking defensive systems (e.g., barriers, surveillance and sensor gear, oversight personnel, response teams, drones) with the security of a relatively unified and restricted area, i.e., that occupied by complexes 3900 and 4000, in contrast to securing a number of disparately located facilities connected by relatively long, costly, and vulnerable pipelines, transport routes, and power lines. Environmental benefits are also realized, e.g., by decreased land consumption for pipelines, power lines, and the like; by the increased feasibility of energy-intensive, environmentally beneficial processes such as manufacture of synthetic fuel from atmospheric carbon, dissolved oceanic carbon, fossil-fuel feedstocks, and/or Eh from electrolysis; by increased feasibility of carbon sequestration from industrial processes and fuel synthesis; and the like.

[00195] In an illustrative use case, a coastal industrial enterprise of foreseeably temporary' nature (e.g., mining of a finite resource) can realize advantages from the deployment of floatable module units in an agro-industrial complex, as these can be deployed rapidly and economically un-deploy ed by similar means at the end of project lifetime, again with potential realization of environmental benefits. These and other advantages are realized by various embodiments. Comprising of floatable module units by the proposed agro-industrial complex is unique and distinctive from all prior proposals for nuclear-powered complexes, e.g., Nuclear Energy Centers: Industrial and Agro-Industrial Complexes , Oak Ridge National Laboratory ORNL-4290, Nov. 1968, the teaching of which is incorporated herein by reference.

[00196] FIG. 41 is a schematic depiction of relationships between portions of an illustrative Power Generating Station-powered natural gas processing facility 4100, illustrative of a class of embodiments in which Power Generating Stations supply power for the extraction and/or processing of fuels. The facility 4100 comprises a Power Generating Station 4102 that supplies energy 4104 (heat and/or electricity ) to a gas treatment process 4106 and a natural gas liquefaction process 4108. The treatment and liquefaction processes 4106, 4108 are preferably located proximally to a coastal or littoral setting where the nuclear plant 4102 can be delivered by flotation, but may be located anywhere to which transmission facilities may effectively deliver the energy output 4104 of the power plant 4102. The gas treatment process 4106 comprises, per standard industrial practice, devices or processes for feed gas compression 4110, condensate removal 4112, dehydration/mercury removal 4114, acid gas removal 4116, and lean gas compression 4118. Acid gas 4120 is delivered to a process of geological sequestration 4122, which comprises an injection compressor. Energy for the geological acid gas

sequestration process 4122 is also preferably supplied by the nuclear plant 4102. The gas treatment process 4106 is supplied by a source or feed gas process 4126, e.g., a pipeline or well field, and delivers treated natural gas 4128 to the natural gas liquefaction process 4108 The liquefaction process 4108 comprises devices or process for refrigeration 4130, end flash gas compression 4132, and boil off gas compression 4134. The primary outputs of the liquefaction proces 4108 are liquefied natural gas (LNG) 4136 and fuel gas 4138.

[00197] The foregoing has been a detailed description of illustrative embodiments of the invention. Various modifications and additions can be made without departing from the spirit and scope of this invention. Each of the various embodiments described above may be combined with other embodiments in order to provide multiple features. Any of the

abovementioned embodiments can be deployed on a floating or grounded nuclear plant platform located in a natural body of water or along a natural or man-made coastline.

Furthermore, while the foregoing describes a number of separate embodiments of the apparatus and method of the present invention, what has been described herein is merely illustrative of the application of the principles of the present invention. Accordingly, this description is meant to be taken only by way of example, and not to limit the scope of this invention.