TECHNICAL FIELD

[0001 ] The present disclosure relates to modelling light propagation onto a structure, and in particular to modelling light propagation onto elements of a structure. Such a method or system can be used to model the performance of photovoltaic components installed on such structures.

BACKGROUND

[0002] Photovoltaic panels and elements are increasingly being used to reduce the carbon footprint of new and existing structures and buildings. On existing structures, such elements are typically added to rooves or installed outside or adjacent to the structure. More recently, Building Integrated PhotoVoltaics, BIPV, are gaining in popularity. BIPV refers to photovoltaic elements that form an integral part of the structure of a building, such as windows, rooftop canopies, shading elements, balustrades or spandrels.

[0003] The demand for electricity produced by such installations is increasing. Additionally, in some situations, there may be commercial, legal or regulatory requirements for the production of electricity. For example, a system provider may be required to certify a certain level of electricity production over a specified period. Therefore, there is a need for accurately modelling the amount of electricity or power produced by a BIPV installation.

[0004] Known methods used to model electricity produced by photovoltaic elements or installations are intended for modelling rooftop installations or installations positioned in open landscapes (such as open fields). Such methods fail to take into account factors or effects that are encountered by BIPV installations, which are commonly found in urban environments. Such effects include, without limitation: complex reflections from surrounding surfaces and structures, detailed shadows from urban environments (e.g., from trees or other foliage), and spectral effects due to reflections and transmissions from surfaces and objects before the light reaches a photovoltaic element.

[0005] EP3913796A2 describes a method of managing and controlling a group of single axis solar trackers provided with bifacial solar panels. Such method can only be used for simplified cases by preforming a limited number of ray tracings under standardized conditions to be interpolated. The prior art is limited to a a single and unique spectral behavior for the surface to be calculated. And said models is limited to diffuse reflections.

[0006] Thus, prior art is limited to single and unrealistic optimization around the theoretical orientation of the set of solar panels with solar tracker.

SUMMARY

[0007] The present invention permits to solve issues of the prior art.

[0008] The present disclosure concerns a method for modelling at least two structural components of a physical structure, the physical structure being comprised of a plurality of physical components, wherein the method comprises: creating a structural model, the structural model being comprised of a plurality of structural components; defining a set of component properties for each of the structural components; providing a set of environmental data; providing a modelled radiation source; defining two or more structural components of interest from the plurality of structural components; using a rendering component to derive at least one characteristic associated with each of the structural components of interest; and optimizing the at least one characteristic associated with each of the structural components of interest.

The steps of providing a set of environmental data and the step of providing a modelled radiation source comprise : - providing environmental source data from at least one environmental data source, the environmental source data comprising a plurality of environmental data components;

- using at least one of the environmental data components to derive the set of environmental data; and

- using at least one of the environmental data components and at least part of the set of radiation source data to derive the modelled radiation source.

The invention permits to discretely optimize each of the plurality of the structural components while taking into account majority of potential reflections of the plurality of the structural components such as mirror effect, glossy surface, ... The present invention can permit to discretely optimize the shape, the orientation, the position and/or the environment around each of the structural elements.

[0009] Additional features of the method are provided in the dependent claims of the present disclosure.

[0010] The present disclosure further concerns a computer program comprising instructions which, when the program is executed by a computer, cause the computer to carry out the method as set out above.

[0011 ] The present disclosure additionally concerns a computer readable medium including program instructions which, when executed by a computer, cause the computer to carry out the method as set out above.

[0012] Further, the present disclosure concerns a computer system, the computer system comprising a processing unit, wherein the computer system is operable to carry out the method as set out above.

BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Other features, purposes and advantages of the invention will become more explicit by means of reading the detailed statement of the non-restrictive embodiments made with reference to the accompanying drawings. [0014] Figure 1 shows an exemplary environment which may be modelled by the present invention.

[0015] Figure 2 illustrates a method for modelling structural components of a structure in accordance with an aspect of the invention.

[0016] Figure 3 shows schematically the method of Figure 2.

[0017] Figure 4 illustrates exemplary steps of providing a set of environmental data and providing a modelled radiations source in accordance with an aspect of the invention.

[0018] Figure 5 shows schematically the method of Figure 2

[0019] Figure 6 shows an exemplary step of using a rendering component to derive at least one characteristic associated with each of the structural components of interest.

[0020] Figure 7 illustrates schematically the method of Figure 6.

DETAILED DESCRIPTION

[0021 ] For illustrative purposes, an exemplary environment will now be discussed with reference to Figure 1. In this example, a structure 102 comprises a photovoltaic component 104 mounted to a face thereof. The photovoltaic component receives radiation 106 from the Sun, which is used to provide electrical power to the structure. The amount of electrical power is dependent on a number of factors, including the weather, the time of day, the time of year, the geographical location of the structure, the direction in which the structure and/or the photovoltaic component is facing.

[0022] Methods exist that are used to predict the electric potential of photovoltaic installations or components. Such methods are typically designed and intended for photovoltaic installations that are mounted on rooftops or in open areas, e.g., fields or other areas free of major structures or obstacles. As such, the known methods fail to accurately predict effects that are typically encountered by BIPV installations. A photovoltaic installation 104A on a rooftop or in an open area receives predominantly direct radiation 106 from the Sun. By contrast, a BIPV installation 104B, 104C is likely to be located in an environment with one or more adjacent structures 108 or buildings, as well as other natural or artificial objects 110 or structures (e.g., trees, roads, paved areas, vehicles, artificial lights, or bodies of water). Therefore, BIPV installations are commonly subject to complex reflections 112 from surfaces from surrounding buildings or structures, including specularity, scattering, diffusion, concentration of reflected radiation, or radiation being reflected multiple times before reaching the photovoltaic element.

[0023] A further example of an effect typically encountered by BIPV installations is detailed shadows caused by urban environments. In such an environment, partial modification or shading of the incoming radiation 114 may take place due to from adjacent or neighbouring structures or objects. This may, for example, be due to transparent, semi-transparent or diffusive surfaces on said adjacent structures. Additionally, incoming radiation 116 may be temporarily affected by shading, e.g., from trees 118 or vegetation with foliage that varies between summer and winter.

[0024] A further example of an effect typically encountered by BIPV that is not predicted by known methods is the spectral nature of radiation, both as emitted by the Sun and any spectral modifications to radiation being caused by being reflected or transmitted by other objects prior to reaching the photovoltaic element. In particular for photovoltaic elements, the spectral distribution of the radiation is important, and any variation or modification in the spectral distribution of radiation hitting such an element may have a significant impact on the efficiency and output of the element.

[0025] It should be noted that the above is not an exhaustive list, and that the above-mentioned effects are purely discussed for illustrative purposes.

[0026] An exemplary method and system for modelling structural components of a structure will now be discussed with reference to Figure 2 and Figure 3.

[0027] In a first step 201 , a structural model 320 is created, the structural model being comprised of a plurality of structural components 322. The structural model may be a model of a suitable structure, e.g., a building or other architectural structure (not shown).

[0028] In the examples described in the present disclosure, the structural model is used to model the structure of a building of interest or otherwise to be examined. Whilst referred to as a building for purposes of the present example, the structural model could, of course, be used to model any type of physical structure of interest. For purposes of the present disclosure, any physical structure in respect of which it may be of interest to mount photovoltaic components thereon or in the vicinity thereof may be modelled. The structural model is comprised of a number of structural elements that are dimensionally identical to the actual components of the physical structure or building. The structural model, and the structural elements therein, is oriented in a manner that corresponds to the physical structure or building. For example, if the physical structure is oriented with its cardinal axis in a North-South direction, the structural model is oriented in the same manner. Additionally, the structural model, in some examples, comprises one or more adjacent or additional structures, e.g., neighbouring buildings, artificial or natural architectural or geographical features that may affect the light hitting the building in question.

[0029] The structural model 320 may be created or otherwise defined in any suitable fashion. In some examples, the structural model is created by way of a modelling application 324 or software. For example, the structural model may be created by a building designer or architect in a suitable design application. In some examples, the structural model is generated or created by an application, system or algorithm. The structural model and the structural components therein may be formatted, encoded or encrypted in a suitable manner. The structural elements of the structural model may comprise any suitable properties or data relating thereto. For example, the structural elements may be comprised of exclusively geometrical data, e.g., the dimensions of the respective structural elements.

[0030] Each of the structural elements of the structural model may represent any suitable or relevant part or portion of the physical structure. In some examples, each of the structural elements of the structural model has substantially the same dimensions and geometry as a corresponding physical component of the physical structure. Any discrepancies between the dimensions and/or geometry of the structural model and the physical structure may influence or reduce the accuracy of the results. In some instances, known methodologies modify and/or simplify the dimensions or geometry of structural models in order to reduce computational complexity. Such modifications or simplifications can negatively impact the accuracy of the results obtained thereby. By establishing correspondence between the dimensions and geometry of the structural model and the physical structure, the accuracy of the subsequent method steps is maximized. In some examples, the dimensions, geometry and/or features of each structural element are modelled or defined within a first tolerance of the dimensions, geometry and/or features of the physical components to which they correspond. In some examples, the first tolerance defines the maximum deviation between the dimensions or geometry of the structural component and the dimensions or geometry of the corresponding physical component. In some examples, the first tolerance is implemented as a lower limit for the size of features or portions of the geometry of the physical component that are defined in the structural component during the creation step. Features or portions of the geometry of the physical components that are smaller than this lower limit are not included when creating the structural components of the structural model. In certain circumstances, omitting features smaller than a lower limit can reduce the computational resources required for carrying out the method. In an example, the lower limit is 1 meter; optionally 50 cm; optionally 25 cm; optionally 15 cm; optionally 10 cm; optionally 5 cm; optionally 2 cm; optionally 1 cm; optionally 5 mm; optionally 1 mm. The smaller the lower limit is set, the greater the precision of the structural model, and, by extension, the greater the accuracy of subsequent method steps.

[0031 ] It will be appreciated that each of the structural elements may, themselves, be comprised of other structural elements or sub-elements. For example, a ‘window’ element may in some examples be comprised of a ‘frame’ sub-element and a ‘window pane’ sub-element. Each of these structural elements or sub-elements may be modelled and defined individually. By defining each feature of a structure, it is ensured that light propagation and optical phenomena, e.g., optical reflections, are modelled accurately. For example, by defining both the frame and the window pane, it is possible to model light being reflected by the frame onto the window pane from which it is once again reflected. By contrast, in some known methodologies commonly model structural elements such as windows as a simple surface or polygon (e.g., a cuboid). This does not allow for the modelling of such complex reflections, which degrades the accuracy of the modelling results in the known methodologies when compared with the methodologies of the present disclosure. In other examples, however, the structural elements are comprised of additional properties, data fields or information structures. For example, each structural element may comprise material data or other data relating to the properties of the material. For example, each structural element may comprise a material or type designator, which may be used in other method steps. Such designators can, for example, be used to label a particular structural elements as ‘window glass’, ‘steel’ or ‘wood’, and may be used in some applications for purposes of rendering or visualization. This can allow a user to quickly render the structural model for a specified purpose, such as a presentation or as a reference. However, for purposes of methods of the present disclosure, a material designator is not sufficient since it is not guaranteed to contain any properties relevant for determining the optical behaviour or characteristics of the structural element.

[0032] In a second step 202, a set of component properties 326 is defined for each of the structural components 322. The set of component properties may comprise any suitable data or information. In some examples, the set of component properties comprises one or more optical properties, optical characteristics or optical component parameters, including (but not limited to): colour; material; transmission coefficient; reflectance coefficient; transmission spectrum; reflection spectrum; surface roughness; refractive index; absorptive index; radiation emission properties; or other material properties.

[0033] The set of component properties 326 may be defined in any suitable manner. In some examples, the set of component properties is defined by a user. In an example, the user selects each component property 328 in the set of component properties from a predefined values or sets of values, such as may for example be stored in a database. In an example, for each structural component the user selects a set of component properties. In some examples, the set of component properties is wholly or partially selected or chosen from one or more predetermined sets of component properties. In some examples, the one or more predetermined sets of component properties are stored in a database.

[0034] Some or all of the component properties or optical component parameters may comprise a spatial parameter distribution that defines the value of the property or parameter over a relevant surface of the corresponding structural component. This allows variations of such parameters to be taken into account in the steps of the present method. Purely as an illustrative example, an optical component parameter may be a reflectivity parameter that varies across the surface of a structural component.

[0035] Some or all of the component properties may comprise a spectral sensitivity. The spectral sensitivity defines the value of the property or parameter as a function of a radiation wavelength or frequency. Purely as an illustrative example, the relevant component property may be a refractive index of a structural component that is dependent on the incoming radiation.

[0036] Some or all the component properties may comprise an angular dependency, which defines the value of the property as a function of the incoming angle of the radiation. Purely as an illustrative example, the relevant component property may be a reflection coefficient that is dependent on the angle of the incoming radiation.

[0037] In other examples, the set of component properties 326 is defined automatically based on one or more criteria. One illustrative example of such a criterion is a designator 330, such as has been briefly described above, of a respective structural component 322. During, or subsequently to, the creation of the structural model, a type or material designator may be applied to the structural component. The type or material designator may, for example, describe the type of the structural component (e.g., a window, a wall panel, or a photovoltaic element). Once the designator is applied to a structural component, a predetermined set of component properties is associated with the structural component. In some examples, at least some of the structural components 322 of the structural model 320 comprise one or more subcomponents 332, which in some examples comprise properties of their own. In such examples, each sub-component is associated with a respective set of sub-component properties 334. For example, a window component may comprise a window pane as well as a window frame. In such examples, a designator may be set for the structural component, which in turn will automatically cause any sub-components to be dealt with. For example, a designator for a structural component may be ‘window’. The ‘window’ component is, for purposes of the present example, defined with a ‘pane’ subcomponent and a ‘frame’ component. The ‘pane’ and the ‘frame’ are associated with separate sets of sub-component properties 334. Purely for purposes of conciseness and clarity, reference will in the following be made to only a single set of component properties, although it will be understood that each component could, in principle, be associated with a plurality of sets of component or sub-component properties.

[0038] The set of component properties 326 is provided in a suitable manner, e.g., by way of a database 336 of component properties. Additionally or alternatively, the set of component properties is obtained in a suitable fashion and from a suitable source or sources 338. In some examples, at least some of the component properties are based on physical measurements. For example, the component properties may be determined by way of a suitable instrument or device, e.g., a spectrometer, a photo-goniometer or a refractometer. In some examples, at least some of the component properties are based on calculations or determination based on one or more theoretical models or simulations. It will be appreciated that this example is purely for illustrative purposes and should not be interpreted to be limiting.

[0039] Further, although described in the present example as two discrete steps, the first 201 and second 202 steps of the present method may, in principle, equally well be performed as a combined method step. For example, during creation of the structural model, the set of component properties may be specified for each structural component by a user. By way of illustration, the user may be utilizing a modelling application that enables object properties to be specified during the modelling stage. In another example, the set of component properties is defined automatically based on one or more criteria during the modelling stage, in a manner similar to that described above.

[0040] In a third step 203, a set of environmental data 340 is provided. The environmental data is used to describe expected lighting conditions that correspond to the geographic area or location in which the structure is to be placed. In some examples, the set of environmental data comprises data that describes the effect of local weather in a particular geographic location. This is to take into account that certain locations may have similar lighting levels (e.g., if they are located at similar longitudes), but may have significantly different weather patterns.

[0041 ] The set of environmental data 340 may comprise any suitable or relevant data. In some examples, the set of environmental data comprises data for one or more intended geographical locations. In some examples, the environmental data comprises sky radiation data for the one or more intended geographic locations. In examples, the sky radiation data comprises direct and diffuse radiation contributions. In some examples, the set of environmental data comprises data relating to one or more parameters or properties of an environment that affect photovoltaic efficiency. Examples include, without limitation: environmental temperature (e.g., air temperature); wind speed; air pollution level or indices; or atmospheric dust content. [0042] The set of environmental data 340, in some examples, comprises data that is divided into a plurality of time segments. This enables the method to take into account environmental effects that vary over time, e.g., different lighting conditions as a result of changing weather conditions or the time of day. The set of environmental data, in specific examples, comprises a subset of data for each of the plurality of time segments. Each subset of data effectively represents the environmental conditions at an intended geographical location for the respective time segment.

[0043] The set of environmental data 340 may be divided into any suitable number of time segments, each time segment representing any suitable or advantageous amount or unit of time. In some examples, each time segment represents a day. In other examples, each time segment represents an hour. In other examples, each time segment represents a minute. It will be appreciated that, in principle, the time segments may represent any suitable amount or unit of time.

[0044] The set of environmental data 340 may be provided in any suitable fashion. In some examples, the set of environmental data is provided by a database (not shown). In some examples, the database is a database of historical weather data.

[0045] If the database does not comprise data for a specific intended geographical location, it may be necessary to perform one or more additional operations in order to provide the set of environmental data. This may, for example, be the case if the above-mentioned database of historical weather data does not comprise data for the intended geographical location but comprises data for locations in the vicinity or within a suitable distance of the intended geographical location.

[0046] The step of providing, in some examples, comprises a step of deriving the set of environmental data based on at least one set of source data. The source data may, for example, be stored in the database. Such derivations may be necessary in cases where the source data does not accurately match one or more aspects of the structural model, such as the intended geographical location. Such a derivation step may be conditional, and may comprise a check to determine whether or not the database comprises suitably matching data. In an example, the database comprises historical weather data for a number of geographical locations. If the database comprises data for the intended geographical location, the data for the intended geographical location is extracted from the database.

[0047] In other examples, the step of providing a set of environmental data comprises a step of deriving the set of environmental data based on one or more sets of training data. The derivation may be performed in a suitable manner, and using any suitable training data sets. In some examples, such a derivation step is performed by way of a machine learning or neural network algorithm. In one such example, the machine learning algorithm is trained on a set of historical weather data for a number of geographical locations. Based on the training data, the machine learning algorithm is used to provide the set of environmental data for the intended geographical location for any specified period of time.

[0048] In a fourth step 204, a modelled radiation source 342 is provided. The modelled radiation source may be provided in any suitable fashion. The modelled radiation source may have any suitable set of properties or characteristics.

[0049] The modelled radiation source 342 provides a source of modelled radiation having a suitable set of radiation properties 344. In some examples, the radiation properties approximate or correspond to one or more real world measurable properties of radiation from one or more radiation sources. Examples include (without limitation): intensity, wavelength, or source position data. In some examples, the modelled radiation source comprises a modelled radiation spectrum. By including such properties, the propagation of radiation can be modelled in more detailed, thereby increasing the precision of the present method. In some examples, the modelled radiation spectrum comprises a plurality of discrete radiation components, each radiation component comprising data or information associated with one or more radiation wavelengths or sub-spectra. In some examples, modelled radiation emitted by the modelled radiation source has a set of properties that mimics the properties of natural light provided by the Sun. In an example, the modelled radiation spectrum comprises a solar emission spectrum that is substantially identical to that emitted by the Sun. In another example, the modelled radiation spectrum comprises a solar emission spectrum that is substantially identical to that emitted by the Sun as well as a diffuse emission spectrum. In some examples, the modelled radiation source comprises position data, so as to model the position of the modelled radiation source relative to the modelled structure. In some examples, the position data corresponds to the position of the Sun relative to the physical structure. This ensures that natural light can be accurately modelled. In an illustrative example, the Sun is modelled as a standard illuminant. In a particular example, the Sun is modelled as standard illuminant D65, as defined by the International Commission on Illumination.

[0050] In examples wherein the modelled radiation spectrum comprises a diffuse emission spectrum, the diffuse emission spectrum may itself comprise any suitable components. In an illustrative example, the diffuse emission spectrum comprises a spectral distribution and an intensity distribution. Each of the distributions may be defined in a suitable fashion and may comprise any suitable or relevant number of data points.

[0051 ] In some examples, the modelled radiation source 342 comprises only a first subset 344A of a plurality of radiation properties, and is missing a second subset 344B of the plurality of radiation properties. For example, the modelled radiation source may be a standard illuminant D65. However, the standard illuminant D65 does not comprise spectral radiation information for the entirety of the emission spectrum of the Sun. The output of a photovoltaic component is highly dependent on the spectral composition of incoming radiation, which, in some instances, include radiation not included in the D65 spectrum. For example, crystalline silicon (cSi) photovoltaic panels are able to convert radiation with wavelengths up to approximately 1100 nm, whereas Gallium Arsenide (GaAs) photovoltaic panels are only able to convert radiation with wavelengths up to 890 nm. In order to maximize the accuracy of the present method, including spectral radiation information in the subsequent steps is advantageous. Therefore, in some examples, the fourth step 204 comprises a sub-step 204A of deriving the second subset 344B of the plurality of radiation properties.

[0052] As discussed above, in order to ensure that the present method provides accurate results, it is necessary to consider and take into account the spectral nature of the radiation incident on a photovoltaic component. The spectrum of radiation coming from the Sun and the sky vault depends on a number of factors, including the season or time of year, the time of day, as well as the weather conditions. When taken in combination with the transmission and reflection properties of the various components in the environment, as discussed above with reference to steps 201 and 202, it is possible to determine properties of radiation that reaches any photovoltaic components.

[0053] The sub-step 204A may be carried out in any suitable fashion and by way of any suitable methodology. In some examples, the sub-step comprises retrieving spectral radiation information from a reference source. Any suitable reference source may be used. In an example, the reference source is a reference spectrum. Purely by way of illustration, in an example, the reference source is a reference spectrum as defined in standard CEN - EN 410. In other examples, the spectral radiation information is determined from a number of data sources or parameters. In one such example, spectral radiation information is determined based on an absorption spectrum of the atmosphere, a model of the air mass of the atmosphere and the position of the radiation source (e.g., the Sun). By modelling the path of the radiation emitted by the Sun through the atmosphere, the radiation spectrum of the Sun that impinges on the structural model can be determined.

[0054] Similarly to the set of environmental data 340, the modelled radiation source 342, in some examples, comprises data that is divided into a plurality of time segments. This enables the method to take into account the temporal variation of the radiation output of the modelled radiation source. For example, the amount of light emitted by the Sun, as well as the spectral composition of this light, varies throughout the course of the day. The modelled radiation source 342, in specific examples, comprises a subset of data for each of the plurality of time segments. Each subset of data effectively represents the environmental conditions at an intended geographical location for the respective time segment.

[0055] The modelled radiation source 342 may be divided into any suitable number of time segments, each time segment representing any suitable or advantageous amount or unit of time. In some examples, each time segment represents a day. In other examples, each time segment represents an hour. In other examples, each time segment represents a minute. It will be appreciated that, in principle, the time segments may represent any suitable amount or unit of time.

[0056] It will be appreciated that, whilst described as discrete steps in the present example, the third 203 and fourth 204 steps may be performed as one combined step. Further, whilst described sequentially, the third and fourth steps may be performed in the opposite order or substantially simultaneously. An exemplary and illustrative implementation of the third 203 and fourth 204 steps will be described in more detail in the following.

[0057] In a fifth step 205, two or more structural components of interest are defined from the plurality of structural components 322. The structural components of interest may be defined in any suitable fashion and using any suitable criterion or criteria. In some examples, the components of interest are defined by a user or other party. In some examples, the components of interest are defined automatically by a suitable component based on one or more selection criteria.

[0058] In a sixth step 206, a rendering component 346 is used to derive at least one characteristic 348 associated with each of the structural components of interest. Any suitable rendering component may be used.

[0059] The rendering component 346 may derive the at least one characteristic 348 in any suitable fashion. In some examples, the derivation step comprises a number of sub-steps. In specific examples, the derivation step comprises one or more rendering sub-steps and one or more subsequent determination substeps, wherein the one or more characteristic is determined based on the result of the one or more rendering sub-steps.

[0060] Any rendering sub-steps may take into account any suitable parameters and properties of one or more of: the structural model; the structural components of the structural model; the set of environmental data; or the modelled radiation source. Any combination of parameters and properties may be used. In an example, all parameters and properties of each of the structural model; the structural components of the structural model; the set of environmental data; or the modelled radiation source are used to perform the rendering sub-step. This allows complex optical effects to be taken into account. Further, given the level of detail of the structural model and the components thereof, the amount of radiation that impinges on any given surface can be precisely modelled, which allows phenomena such as partial shade, partial transmission, transmission spectra, or reflection spectra to be taken into account.

[0061 ] Known methods typically take into account only a subset of the relevant parameters and properties. For example, some known models only model the radiation intensity of the radiation source, but do not model the spectral properties of the radiation source. Further, some known models do not take into account the spectral response or properties of any of the structural components. For example, some known methods use the standard illuminant D65 to model the radiation source as mentioned above, but do not additionally comprise any spectral information (such as in the present disclosure). Further, known methods typically determine parameters averaged over the entirety of the surface of a component of interest or determined at a specific position (such as the centroid) on the surface of the component of interest. This is due to computational and resource limitations in known methods. Traditionally, modelling complex structures is too computationally intensive and is therefore either not possible or too slow. As a result, renderings performed by known methods are less accurate than the methods presented in the present disclosure.

[0062] It will be appreciated that, a number of specific implementations of the deriving step may be envisaged within the scope of the present disclosure.

[0063] Any suitable characteristic or characteristics associated with one or more of the structural components of interest may be derived. In examples, at least one characteristic associated with each of the structural components of interest is derived.

[0064] In an example, the two or more structural components of interest comprise photovoltaic components, and the derived characteristic comprises an electric conversion efficiency for the two or more structural components of interest.

[0065] In another example, the derived characteristic comprises solar irradiance on the two or more structural components of interest. This may be accomplished in a suitable fashion. For example, the rendering component can be used to determine the solar irradiance on the structural component of interest. For example, the rendering is used to generate a daylight coefficient (i.e., a coefficient linking the radiative power of a region of the sky with the irradiance at a particular position in the structural model). The daylight coefficient is then combined with the modelled radiation source to derive the solar irradiance.

[0066] In a further example, the derived characteristic comprises an amount of electricity generated by the two or more structural components of interest. The amount of electricity can, for example, be determined based on the solar irradiance which may be computed as described above.

[0067] An exemplary specific implementation of the deriving step will be discussed in more detail in the following.

[0068] In a seventh step 207, the at least one characteristic 348 associated with each of the structural components of interest is optimized. The optimization may be performed in a suitable manner and using a suitable set of optimization criteria. [0069] In some examples, the optimization is performed by a user based on the optimization criteria and using the results of the preceding steps of the method. In other examples, the optimization is performed by an optimization component (not shown).

[0070] In some examples, one or more post-optimization steps are performed. In some examples, the at least one optimized characteristic is saved in the respective two or more structural components of interest.

[0071 ] In the above example, the method and system have been described in general terms. A number of aspects will now be discussed in more detail in order to more thoroughly illustrate exemplary implementations of the present disclosure.

[0072] As discussed above, the steps of providing a set of environmental data and providing a modelled radiation source may be implemented in a number of specific fashions according to the present disclosure. For illustrative purposes, exemplary providing steps will now be discussed with reference to Figure 4 and Figure 5.

[0073] In a first step 401 , environmental source data 550 is provided from at least one environmental data source 552, the environmental source data comprising a plurality of environmental data components. The environmental source data may comprise any suitable or relevant environmental data components 554, including (but not limited to) one or more of: direct radiation data; diffuse radiation data; radiation spectral data; time-dependent data; or geographical position-dependent data. The environmental data components, in some examples, additionally or alternatively comprises data relating to one or more properties, characteristics or parameters of the environment, including (without limitation): atmospheric temperature; wind speed; wind direction; snow amount and direction; atmospheric dust or other particles, atmospheric humidity, or atmospheric turbidity.

[0074] Any suitable environmental data source 552 may be used to provide the source data. In some examples, the data source is a remote data source, e.g., a data server which is accessed remotely by way of a suitable data connection. It will, of course, be appreciated that, whilst only a single environmental data source is shown in the present example, this is purely for illustrative purposes and for ease of explanation. In principle, a plurality of environmental data sources could equally well be implemented.

[0075] The environmental source data provided by the environmental data source 552 may originate from any suitable original source 553. In some examples, the original source 553 comprises weather data that describes expected sunlight conditions and includes the effect of local weather conditions on photovoltaic electricity production. In some examples, the original source comprises a theoretical or numerical model 553A that reconstructs the spatial and spectral distribution of the sky luminance or radiance. Examples of such a theoretical model include, but are not limited to: the isotropic sky model; or the Perez All-Weather Sky Model.

[0076] In some examples, the original source comprises one or more series of measurements 553B. Such measurements may, for example be performed at one or more geographical locations, e.g., the intended location of a building. Such measurements, in some examples, comprise direct measurements of sky luminance or radiance and sky spectrum in every direction at the one or more geographical locations. In some examples, the measurements comprise historical data, such as may have been obtained from one or more nearby weather stations or other similar installations. In specific examples, the historical data is obtained from a single such installation. In other specific examples, the historical data is a reconstruction or combination of data obtained from a plurality of such installations. This may be of relevance in situations where no historical data has been obtained for the specific geographical location. In such examples, a set of data is reconstructed or combined from the historical data by way of a suitable methodology, e.g., a suitable numerical or theoretical model.

[0077] In other examples, the original source comprises a set of predicted data 553C, obtained by way of a suitable methodology. For examples, the set of predicted data may be obtained by way of predictive modelling, e.g., by using a machine learning or artificial intelligence algorithm, or by using a climate change model (e.g., the Representative Concentration Pathway model).

[0078] In a second step 402, a set of radiation source data 556 is provided. The radiation source data relates to a radiation source 558, e.g., a theoretical or numerical model of the Sun. The radiation source data may have any suitable format and may comprise any suitable information. In some examples, the radiation source data comprises irradiance data. In some examples, the radiation source data comprises spectral data relating to the radiation source. In some examples, the set of radiation source data comprises radiation data associated with the Sun. As discussed above, in the present example, the Sun is modelled as a standard illuminant. In a particular example, and as described above, the Sun is modelled as standard illuminant D65, as defined by the International Commission on Illumination. In other examples, the Sun is modelled by a reference spectrum, including (without limitation): a spectrum such as defined in CEN standard EN 410; or a spectrum such as defined in ASTM International standard ASTM G183-03.

[0079] In some examples, the set of radiation source data 556 comprises additional radiation source data 560 relating to one or more additional radiation sources 562. Examples of such additional radiation sources include, but are not limited to: exterior artificial radiation sources (e.g., street lights or other sources of light found in an exterior environment); or interior artificial radiation sources. In some situations, a system may be adjacent or proximal to one or more of such radiation sources which may impact the functioning of a photovoltaic component.

[0080] In a third step 403, at least one of the environmental data components 554 is used to derive a set of environmental data 540. In the present example, the at least one environmental data component used to derive the set of environmental data comprises Diffuse Horizontal Irradiance.

[0081 ] In a fourth step 404, at least one of the environmental data components 554 and at least a part of the set of radiation source data 556 is used to derive the modelled radiation source 542. [0082] As discussed above, the modelled radiation source 542 comprises a radiation source components 564, each describing one or more radiation properties 544 or aspects of the modelled radiation source. In the present example, the modelled radiation source comprises: a radiation intensity component 564A; a spectral component 564B; and a position component 564C. Each of these components may be determined in any suitable manner and based on any combination of source data.

[0083] In some examples, the spectral component comprises a solar emission spectrum. In other examples, such as described in the above, the spectral component 564B is derived based on a number of data sources or parameters. In a specific example, the spectral component is determined based on one or more of: a solar emission spectrum; an absorption spectrum of the atmosphere; a model of the air mass of the atmosphere; and the position component 564C. In effect, the propagation path of the radiation emitted by the Sun through the atmosphere is modelled to determine the radiation spectrum of the Sun that arrives at the structural model.

[0084] In the present example, an illustrative methodology has been described for deriving a set of environmental data and a modelled radiation source. It will be understood that the presently described methodology is purely intended to be exemplary only and is not intended to be limiting in any way.

[0085] An exemplary step of using a rendering component to derive at least one characteristic associated with each of the structural components of interest will now be discussed with reference to Figure 6 and Figure 7.

[0086] In a first step 601 , a rendering 766 is derived by a rendering component 746 based on the structural model 720, the set of environmental data 740 and the modelled radiation source 742. The rendering may be derived in any suitable fashion and by way of a suitable rendering component. In some examples, the rendering component is a spectral raytracer. In some examples, the spectral raytracer uses forwards and/or backwards raytracing. This enables the rendering to take into account complex light propagation phenomena, e.g., caustics, that may impact the amount of radiation propagating to and from the various surfaces of the structural model. Other optical phenomena that may be taken into account by the rendering include, without limitation: partial shade on structural components of interest caused by the shape of two or more structural components of the structural model; partial shade caused by partial transmission of radiation, e.g., through one or more windows; or reflections caused by other structural components, e.g., specular reflections from windows.

[0087] Generally, such phenomena cannot be accurately modelled or taken into account in known methods. As described above, known methods typically determine the average value of a given parameter for the entirety of a surface or component of interest (e.g., the average irradiance or luminance on the surface of a photovoltaic component or the irradiance or luminance at a centroid on the surface of a photovoltaic component). However, in circumstances where a photovoltaic component is partially shaded or obscured, or if the light has been spectrally modified (e.g., because it has been reflected by or transmitted through other structural components, such as windows), such determined parameters are not accurate.

[0088] The rendering 766 may, in some examples, be a static rendering using a specific set of input data. Such a rendering provides a snapshot of radiation arriving at the structural model as well as the structural components thereof.

[0089] In other examples, the rendering 766 comprises a temporal component that enables the lighting and environmental conditions at different times of day or year to be modelled. The temporal rendering may be implemented in any one of a number of specific ways. It will be appreciated that, in some instances, the specific implementation of the temporal rendering is dependent on one or more of the contents of the data sets, the format or properties of the data sets, the properties or characteristics of the rendering component or the structural model. The present example is an illustrative and exemplary implementation of temporal rendering, although it will be understood that this is for illustrative purposes only and is not intended to be limiting. [0090] In the present example, the set of environmental data 740 is segmented into a plurality of subsets 740A, each subset being associated with one of a corresponding plurality of time segments. Further, the modelled radiation source 742 is segmented into a corresponding plurality of subsets 742A, each subset corresponding to one or more particular time segments. As discussed above, each time segment may represent any suitable amount of time, including (but not limited to): 1 day; 4 hours; 2 hours; 1 hour, 30 minutes; 10 minutes; 5 minutes; or 1 minute.

[0091 ] In the present example, the step of deriving a rendering 766 comprises, for each of the plurality of time segments, deriving a rendering sub-component 766A associated with the time segment. In effect, each of the rendering subcomponents substantially contains a snapshot of radiation arriving at the structural model as well as the structural components thereof similar to the static rendering. Each of the rendering sub-components comprises any suitable amount of data or information.

[0092] In a second step 602, a rendering parameter 768 is determined for at least one structural component of interest of the structural model 720. Any suitable or relevant rendering characteristic may be determined for the structural component of interest. In some examples, the rendering characteristic comprises an optical parameter of the rendering associated with the at least one structural component of interest. In some examples, the rendering characteristic comprises an optical parameter of the rendering associated with at least a part of the at least one structural component of interest. In the present example, the rendering characteristic comprises incident irradiance received by the at least one structural component of interest.

[0093] The rendering parameter may comprise any suitable amount of information or data content. In some examples, the rendering parameter comprises data representative of the overall amount of radiation incident on the two or more structural components of interest. Examples include, but are not limited to: overall irradiance; overall spectral irradiance; radiation energy; or radiant flux (e.g., overall radiant flux or overall spectral radiant flux). In some examples, the rendering parameter comprises additional radiation data, such as an overall irradiance on a structural component of interest broken down into one or more radiation components, each of such radiation components being associated with a radiation origin. For example, a particular structural component may be irradiated directly by the Sun and/or irradiated by diffuse light coming from the rest of the sky dome, and may additionally receive reflected radiation from a neighbouring building. Further, the structural component may receive radiation reflected by a surface of the structure to which it is attached, e.g., a terrace, wall, roof or window. In such examples, the rendering parameter comprises one or more radiation components, each of said radiation components comprising radiation data associated with one of a plurality of radiation origins. The radiation data, in some examples, comprises one or more of (without limitation): radiant flux; radiation direction; radiation type; or radiation spectrum.

[0094] In the present example, the rendering parameter, comprises one or more of: the total incident irradiance; a plurality of radiation components, each comprising radiant flux, radiation direction and radiation spectrum; and the overall spectrum of the incident radiation.

[0095] In a third step 603, at least one characteristic 770 is derived based on the rendering and the rendering parameter. In the present example, the at least one structural component of interest is a photovoltaic component, and the at least one characteristic comprises an amount of electricity generated by the at least one structural component of interest. The amount of electricity generated by the at least one structural component of interest may be expressed in a suitable fashion, and may have any suitable format or encoding.

[0096] A number of conversion models exist for evaluating conversion of incident solar radiation to electricity. Such models typically account for one or more of: the type of photovoltaic component, including taking into account whether the component is a single-face type or a bi-facial type; the efficiency of the photovoltaic component to convert incident radiation into direct current energy; loss caused by the temperature increase of the photovoltaic component during use; loss due to soiling or aging or the photovoltaic component; loss due to component or array mismatch (e.g., losses caused by uneven irradiation of individual photovoltaic components or component arrays, for example if part of a component or an array is in shadow and the efficiency of the entire system gets driven by the shaded part); or loss due to DC-AC conversion and ohmic losses from wiring

[0097] In some examples, the conversion model further accounts for the angular dependency of the photovoltaic component. It is known that the direction of incoming radiation affects the amount of radiation energy absorbed by a photovoltaic component.

[0098] In some examples, the at least one characteristic comprises a plurality of characteristic components, wherein each of the characteristic components is associated with one of a plurality of time segments. In such examples, the step of deriving comprises, for each for each one of a plurality of time segments, determining a characteristic component.

[0099] It will be understood that various modifications and/or improvements obvious to the person skilled in the art may be made to the various embodiments of the invention described in the present description without departing from the scope of the invention defined by the appended claims.