BACKGROUND INFORMATION

[0001] FIELD OF THE INVENTION

[0002] The invention relates to energy efficient building structures, in particular buildings having roofing structures and sidewalls that use a number of energy efficient technologies to capture and use heat and solar energy.

[0003] DISCUSSION OF PRIOR ART

[0004] Nearly all building structures include some form of roofing structure and sidewalls, with the exterior side of structure exposed to the natural elements and the interior of the structure typically requiring some form of heating and/or cooling system. Traditionally the heating and cooling systems are provided by installing conventional insulation and conventional heating and cooling machinery that is powered by gas, oil or on-grid electricity.

[0005] However, these systems all incur some amount of ongoing cost in the form of purchasing the gas, oil and/or electricity to power the machinery, and fail to take advantage of natural elements such as solar energy and the changes in temperature that naturally, or artificially, occur throughout the day, thereby presenting an inefficient energy system. As energy requirements continue to rise, these issues become more problematic.

[0006] What is needed, therefore, is an energy efficient building structure that is able to harness solar energy and capture the energy that is generated through the normal changes in temperature that occur throughout the day. BRIEF SUMMARY OF THE INVENTION

[0007] The invention is an energy efficient building structure having a multi-layer roofing structure and multi-layer sidewalls that make use of solar energy and the changes in temperature that occur throughout the day.

[0008] Both the roofing structure and the sidewalls incorporate a layer containing phase change materials (PCM). PCMs are substances that melt and solidify at specified temperatures and, because they have a high heat of fusion, are capable of storing and releasing large amounts of energy. When the temperature is above the melting point heat is absorbed by the PCM and it changes from a liquid to a solid, and when the temperature falls below the melting point the PCM releases the heat and changes from a solid to a liquid. Any PCM that has the desired melting point may be used, for example an organic PCM, such as paraffin, or inorganic PCMs, such as salt hydrates, may be used so long as they have the proper melting point.

[0009] Depending on the environmental conditions and melting temperature of the PCM it is possible that the PCM layer, for example, stores heat during the daytime hours when the temperature is high and then releases heat during the nighttime hours when the temperature is low.

[0010] The roofing structure may be arched in a manner similar to a greenhouse or flat, and includes a PCM layer on the inner portion of the structure, followed by a layer of insulation, a plurality of light-transparent arches, a layer of polycarbonate sheets or panels, and a layer of flexible solar panels. Purlins are used to mount the roofing structure to the building structure, and to create an air cavity between the insulation and the polycarbonate panels. The layers are attached to one another using conventional means. Vents and fans may also be provided to help direct the flow of air. In use, the PCM layer stores energy during times of relatively high temperature and releases that energy in the form of heat during times of low temperatures. The vents and fans may be used to gather more heat to charge the PCM layer faster, or, alternatively, to vent heat out of the building if the temperature is higher than desired. The PCM is also able to absorb excess heat during the day and the same system for bringing air in from the air cavity may be used to circulate cooler air in the structure to help dump the heat that has charged the PCM during the day. In this way the thermal mass of the PCM recharges itself and readies itself to absorb excess heat during the following diurnal cycle.

[0011] The sidewalls have an outward appearance similar to conventional building structures, but are layered panels that include a PCM layer, a layer or insulation, and a layer of polycarbonate, all sandwiched between conventional structural boards. As with the roofing structure, the PCM stores and releases heat according to the air temperature. The sidewall may also include a heating element that can further charge the phase change material, store heat and provide higher insulative value while the PCM is charged.

[0012] The same layered panels that are used as sidewalls may also be used as a flooring structure. When deployed as a flooring system, these individual panels are inter-lockable and contain a non-corrosive stabile outer material such as fiber- reinforced plastic. The floor panels contain an internal structural member such as an l-Beam, closed or low density foam for insulation, and PCM for heat storage as well as an optional heat exchanger such as radiant heat piping, pex tubing, or resistance heating such as a coil or carbon fiber.

[0013] The roofing structure is attached to the sidewalls using any suitable conventional means. The roofing structure and/or the sidewalls may be used in connection with one another, or they may be used individually with other forms of building structures as desired. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The present invention is described with reference to the accompanying drawings. In the drawings, like reference numbers indicate identical or functionally similar elements. The drawings are not drawn to scale.

[0015] FIG. 1 is a front view of a building structure according to the invention.

[0016] FIG. 2 is a front view of the building structure without the siding.

[0017] FIG. 3 is a side view of the building structure.

[0018] FIG. 4 is a top view of the building structure.

[0019] FIG. 5 is a side view showing a close-up of the roofing structure and sidewall and their connection to one another.

[0020] FIG. 6 is a side perspective view of a fan and vent in the roofing structure.

[0021] FIG. 7 is a front view of the building structure having a fan and vent in the top of the roof.

[0022] FIG. 8 is a front view of the roofing structure having top-mounted doors, the doors being in a closed position.

[0023] FIG. 9 is a front view of the roofing structure having two doors with the left door open.

[0024] FIG. 10 is a top perspective view of the roofing structure doors having solar panels.

[0025] FIG. 11 is a bottom perspective view of the roof doors and the actuation system. [0026] FIG. 12 is a front view of the roof doors and actuation system.

DETAILED DESCRIPTION OF THE INVENTION

[0027] The present invention will now be described more fully in detail with reference to the accompanying drawings, in which the preferred embodiments of the invention are shown. This invention should not, however, be construed as limited to the embodiments set forth herein; rather, they are provided so that this disclosure will be complete and will fully convey the scope of the invention to those skilled in the art.

[0028] FIGS. 1 - 5 illustrate a first embodiment of the energy efficient heating and insulating building structure 100 that includes a roofing structure 10 and sidewalls 50. Both the roofing structure 10 and the sidewalls 50 make use of a number of energy efficient materials to capture, use, and, optionally, to store solar energy, primarily to heat and/or cool the building structure 100. The roofing structure 10 is affixed to the sidewalls 50 using conventional means.

[0029] The roofing structure 10 is a layered combination of materials that are in the form of panels and/or sheets and that are affixed to a plurality of arches.

Together, the combination of layers captures and uses solar energy and heat to heat, cool and provide electricity to the building structure 100.

[0030] The roofing structure 10 includes a PCM layer 12 and an insulation layer 14 that are affixed to a plurality of light-transparent arches 16. The PCM layer 12 is comprised of a number of conventional sheets or panels that encapsulate a PCM. In general, conventional PCM sheets are somewhat pliable and lack rigidity when the PCM is in a liquid state, and in these instances it may be desirable to add a support layer 29 to add rigidity to the PCM layer 12. The support layer may by any suitable from of rigid membrane, such as acrylic or polycarbonate panels. The insulation layer 14 may be any suitable form of conventional insulation, such as rolled or bagged insulation that is typically used in attics and/or batting or blown-in insulation. The arches 16 are constructed of any suitable material such as fiber glass, for example, CLEARSPAN arches.

[0031] One or more purlin 18 connect the arches 16 to layer of polycarbonate panels 22 and creates an air cavity 24 between the arches 16, and the layers beneath the arches, and the polycarbonate layer 22. Flexible solar panels 26 may be laminated onto the outer surface of the polycarbonate layer 22 or they may be mechanically affixed using conventional means. The layered design of the roofing structure 10 allows solar radiation to pass through the solar panels 26 and

polycarbonate layer 22 and into the cavity 24, where it is absorbed by the PCM layer 12. The solar panels are connected to conventional solar collection system that includes an inverter and, optionally, storage batters (not shown) to store the solar energy. One or more purlins 19 are also used to provide structural support for the roofing structure 10 and to help secure the roofing structure 10 to the building structure 100.

[0032] Intake vents 28, shown in FIGS. 1, 2 and 7, may be provided near the bottom of the roofing structure 10 or sidewalls 50, and a solar powered fan 32 and fan vent 34, shown in FIGS. 6 and 7, may be provided at or near the top of the structure to pull air into the air cavity 24 through the intake vents 28 and/or the fan vent 34 and either into or out of the building structure 100 as desired. Conventional ducts and/or piping may be provided to direct and/or convey air from the intake vents 28 into the roofing structure as desired. For example, the fan 32 and vents 34, 28, may be used to charge or discharge the PCM Layer 12 by pulling air into the roofing structure or they may be used to circulate the air from inside the building 100 to outside the building 100 or vice versa. [0033] More particularly, if the air temperature outside of the cavity 24 is higher than it is inside the cavity, and a user wishes to provide a faster charge to the PCM layer 12, outside air may be pulled into the cavity 24. Conversely, if the change in temperature has provided a greater charge than is needed to PCM layer, and the air inside of the cavity is greater than the air outside the cavity, the cooler air may be pulled in to the cavity to provide a faster discharge of the PCM layer 12, or, the warmer air in the cavity may simply be vented out of the cavity through the vent 34 to slow the rate at which the PCM layer charges. More specifically, when air having a temperature above the melting point of the PCM layer 10 is pulled into the building, it will naturally result in a phase change of the PCM, thereby charging the PCM layer 12. Or, for example, during periods of high daytime temperatures such as during the summer months, during the nighttime hours cooler air may be brought into the building to cool the temperature inside the building in order to discharge some of the energy that has been absorbed by the PCM. In this manner the roofing structure 10 is also able to help cool the building by purging the excess heat through circulation and convection. The PCM layer 12 helps absorb unwanted heat that comes in through the insulation to keep the building comfortably cool and then is discharged at night by circulating cool air into the building, and allowing for the PCM to recharge in the morning.

[0034] Similarly, when the temperature outside the building 100 is greater than the temperature inside the building, the air may be pulled into the building through the fan 32 in order to warm in inside of the building, if desired. Conversely, when the air is warmer inside building than it is inside the cavity 24, the cooler air in the cavity 24 may be vented out through the fan vent 34, or, if desired, it may be pulled into the building 100 through the fan 32 in order to lower the interior temperature.

[0035] Additionally, FIGS. 8 - 12 illustrate the roofing structure 10 having two doors 38 that are coupled to the roofing structure 10 approximately near the top of the roof 10 that may be covered by solar panels 42. The doors 38 are controlled by conventional motorized systems 44, such as a rack and pinon system, which allows the doors 38 to be positioned at varying degrees of openness to best position the door relative to the sun for optimum solar gain. The solar panels 42 are connected to the buildings electrical and/or heating systems using conventional means. When the temperature inside the building 100 is greater than the temperature outside the building 100 and greater than the desired temperature within the building 100 the doors 38 may be opened to allow for ventilation of the unwanted heat.

[0036] The side walls 50, which are best illustrated in FIGS. 2 and 5, are in the form of a structural insulated panel (SIP) 52, which are used for traditional building structures, but that include the Phase-change material (PCM) Layer 54, an insulation layer 56 and a polycarbonate layer 58, all sandwiched between conventional boards 59. As with the roofing structure 10, the PCM layer is a panel or sheet that encapsulates the PCM, the insulation is conventional insulation that is suitable for use with a SIP, and the polycarbonate layer is a conventional sheet or panel of polycarbonate. Conventional fans 62 may also be placed in the sidewalls 50 to circulate or exchange air. Conventional windows 64 may also be provided.

[0037] The roofing structure 10 is connected to the sidewalls 50 using any suitable conventional means. For example, as shown in FIG. 5, a steel beam 66 is affixed to the top inner side of the sidewall 10, and a plate 68 having a pin slot 72 is affixed to the beam 66 and connects to the roofing structure 10. Horizontal beams 61 may also be used to secure the roofing structure to the sidewalls.

[0038] In both the roofing structure 10 and the sidewall 50, the PCM layers 12, 54, have a specified melting point that is defined prior to installation, based on the intended purpose of the structure. For example, the PCM layer 12, 54 that is chosen for use in an office building may have a melting point of 70 degrees Fahrenheit and the PCM layer 12, 54 that is chosen for use in a warehouse may have a melting point of 55 degrees Fahrenheit. When the temperature rises to the specified melting point, the PCM 12, 54 charges, i.e., it begins to change phase from solid to liquid and, in so doing, absorbs a large amount of heat without a significant change in temperature of the PCM. It continues to absorb heat at an almost constant temperature, until all the material has changed to a liquid state. This allows the PCM layer 12, 54 to function as a latent heat storage device. Once the temperature drops below the melting point, the PCM layer 12, 54 begins to solidify and release its stored latent heat. The PCM may be encapsulated in any suitable material, such as, for example, polyethylene foil laminate or metal or plastic tubes. An example of a suitable material for the PCM layer 12, 54 is Infinite R PCM, manufactured by Insolcorp, with a specified melting point of 65 degrees Fahrenheit. As such, the roofing structure 10 and the siding 50 naturally charges and releases heat as the temperature rises above and falls below the melting point.

[0039] A heating source 70 may be provided when the device 100 is used in an environment in which the ambient temperature does not rise sufficiently or fast enough to charge the PCM layer 12, 54 or in situations in which a faster charge is desired. The charged PCM produces latent heat creating an insulating effect inside the structure for the duration of time that the material holds its charge.

[0040] The heating source 70 may be provided in the form of strips of carbon fiber adhesive tape that are connected to a source of electricity and are applied directly to the PCM layers 12, 54, or may be sheets of carbon fiber material that are laminated onto the PCM layer 12, 54, or other resistant heaters or hydronic heat sources. Strips of carbon fiber are an effective way of raising the temperature to the specified melting point because they may be spaced proportionally across the building structure 100, are light weight and allow for solar or electrical charging, thereby achieving rapid charging of the PCM layer 12, 54. The heating element 70 may be charged using any number of conventional means, or, electricity may be provided by installing a photovoltaic (PV) system on a portion of the roof, for example, on top of the rafters.

[0041] It is understood that the embodiments described herein are merely illustrative of the present invention. Variations in the construction of the energy efficient building structure may be contemplated by one skilled in the art without limiting the intended scope of the invention herein disclosed and as defined by the following claims.