Supporting integration of photovoltaics in building skin. A software platform for design and evaluation of customized BIPV components in connection with a BIM-based process
Building Integrated Photovoltaics (BIPV) means today the possibility for the building skin to produce renewable energy in a safe, reliable and affordable way. Envelope engineering plays a fundamental role in this challenge and BIPV, along with other innovative technologies and solutions, opens a concrete opportunity to address the target of nearly-Zero or Plus-Energy Building. Most of the BIPV applications, both in opaque and transparent skin, requires a strong integration of energy, electrical, architectural and construction requirements during the whole process, from early-design phase till to manufacturing and operation. A multidisciplinary and integrated planning approach by architects, engineers and manufacturers becomes essential since the initial stage of the project, so that the development of methods, models and tools oriented to optimally support an integrated process (i.e. the BIM approach) is a crucial aspect of growing interest. In the framework of the European project Construct PV, a web-tool has been developed with the goal to support, since the early design phase, the integrated design of a customizable BIPV component for the building skin, within an interoperable process based on Building Information Modeling (BIM). The tool allows the customization of both physical and constructive (materials, dimensions, layers,..) characteristics of a crystalline module with the goal to cover all the main possibilities in terms of product design, such as the module’s layering, the use of different materials, the shape, the cell’s arrangement, etc. with the result to define a 3D geometry of the component in a realistic graphic environment. The second step focused on developing a special plug-in to create the interoperability of the tool within a BIM-based process. Since BIM objects are not just graphical representations, but rather virtual constructions of a real component, they include information, parameters and data, assisting the stakeholders (architects, owners, contractors, etc.) to make better-informed and shared decisions throughout the building lifecycle. The research is expected to cover a first step for supporting an optimization process for the design of advanced systems of building envelope concerning customized BIPV elements, in the perspective of an integrated approach ensuring quality, transparency and time/cost benefits.
Building-integrated photovoltaics (BIPV) are photovoltaic materials that are used to replace conventional building materials in parts of the building envelope such as the roof, skylights, or facades. They are increasingly being incorporated into the construction of new buildings as a principal or ancillary source of electrical power, although existing buildings may be retrofitted with similar technology. The advantage of integrated photovoltaics over more common non-integrated systems is that the initial cost can be offset by reducing the amount spent on building materials and labor that would normally be used to construct the part of the building that the BIPV modules replace. These advantages make BIPV one of the fastest growing segments of the photovoltaic industry.
Before considering the practical implications of BIM on current working processes, it is essential to consider its definition. As reported in “BIM Overlay to the RIBA Outline Plan of Work”, BIM is widely used as the acronym for ‘Building Information Modelling’ which is commonly defined using the Construction Project Information Committee (CPIC) definition as: “…digital representation of physical and functional characteristics of a facility creating a shared knowledge resource for information about it forming a reliable basis for decisions during its life cycle, from earliest conception to demolition”. It is important to note that some observers believe that BIM should be the abbreviation for “Building Information Management” and others use the term BIM(M) alluding to “Building Information Modelling and Management”.
Step 1 – BIPV design webtool for Early Design Phase
Since the architect is often the first player of the building process linked to BIPV, the development of attractive platforms with the function to flexibly support the early design phase is more and more required. A BIPV design tool has been developed with the goal to support the process of concept and design of a customized BIPV element including all the main architectural/constructive design possibilities for crystalline BIPV modules.Launch the web-tool and Log-in (register as a new user) to create a Project. Save a pdf datasheet of your designed component. Export the database (save as) if you’re interested in BIM interoperability for further stages of the design process (see step 2 and 3)
– Before using the webtool it’s only required to install the Unity web-player (for Windows or Mac OS X) on the PC which enables to view blazing 3D content created with Unity directly in the browser, and auto-updates as necessary. If the automatic installation doesn’t work (when you access the tool from the web-browser and after opening a project), please download the Unity web-player and manually run and install the downloaded file *exe. More information at: http://unity3d.com/webplayer (latest accessed: 10/07/2015). Just after this installation, the web-tool is ready to be used directly on your browser.
– The Firefox browser is warmly recommended. Otherwise if the browser version does not support the Unity Web Player plugin (e.g Chrome), it’s usually required enabling NPAPI plugins.
Step 2 – Plug-in for BIM interoperability
Once the design of the BIPV component, in terms of architectural features, has been established, the design of the BIPV element can move from a conceptual phase to the design development adding details and information. The transition to a BIM-based process becomes essential in order to really support the integration of BIPV within the real design and construction process. Thus, the shift from a static component (such as an image, a CAD element, etc.) to a BIM parametric object is the second milestone of the project. Autodesk Revit platform is used in this stage. The Interoperability, that is the interaction of the design tool with Revit, has been solved through the development of a specific plug-in linking the two software. However, since Revit provides IFC import and export based on buildingSMART® IFC exchange standards, there is no limitation to the applicability in the construction sector.
Step 3 – BIM objects for customized BIPV components
The step 2 is very important in order to create, starting from the design tool, an object completely operating in BIM environment with a certain LOD (Level of Development). For this purpose, native Revit families with specific parameters and behaviors have been developed and predisposed to support this “interoperability” thus defining BIM objects of BIPV elements adaptively working and further customizable in BIM environment. These reference families are also adaptive BIM objects with parametric attributes which, besides to be linked to the tool, can be completely customized and autonomously used directly in Revit environment as a BIM object for modelling, design, scheduling, etc. as well as to be further developed and improved by users (BIM operators, coordinators, etc.).
Contact for requesting the plug-in and the BIM Objects
Disclaimer: The tools and platforms exist solely for communicating and disseminating project information and for research purposes. The content and the site does not serve to define any system design or other engineering parameters that are related to the real design process. No claim or representation is made or warranty given as to the accuracy and completeness of the information and results. SUPSI, as information providers, does not accept any liability to any person or entity for any mistake, loss, damage, liability or expense suffered which is claimed to result from use of the information provided by this platform. The information is provided for only research purpose with the understanding that Users accessing the platforms, the files and the documentation assume entirely responsibility for assessing its relevance, accuracy and suitability for application. The eventual mention of specific companies or products of manufacturers does not imply that these have been endorsed or recommended in preference to others of a similar nature that are not mentioned. The use is only admitted by quoting the project “Construct-PV” as the source.
For any further information please contact:
Dr. Francesco Frontini, Dr. Pierluigi Bonomo
University of Applied Sciences and Arts of Southern Switzerland (SUPSI)