Researchers from the École Polytechnique Fédérale de Lausanne (EPFL) and the Swiss Center for Electronics and Microtechnology (CSEM) examined colored crystalline silicon PV module technologies, suppliers, as well as the success factors on the path to meeting the needs of architects and real estate developers with visually appealing building integrated PV (BIPV).
The methods used by manufacturers to produce colored modules, along with the costs, challenges, and advantages were analyzed in the review. It was completed in the context of the team's work on several other European Union and Switzerland-funded research projects, including recent work on a new BIPV illumination colorimeter for module manufacturers.
Color can be added to conventional PV modules in a number ways, such as using colored cover glass made via screen printing or digital ceramic printing, for example. Manufacturers can use colored polyvinyl butyral (PVB), ethylene vinyl acetate (EVA) or polyolefin elastomer (POE) encapsulants. They can add semi-transparent active layers, structured coatings, adhesive patterned foils attached to cover glass, or directly to cells during manufacturing, or even adding color to modules in a post-manufacturing step.
Some of the manufacturers adopting these techniques are profiled by the research team, including European companies, such as Kameleon Solar, Kromatix, Megasol Energy, Onyx Solar, 3s Swiss Solar Solutions, and Freesuns. They are using colorisation techniques provided for by the likes of Solaxess, Kromatix, and Glas Trösch. Others mentioned, include U.S.-based Sistine Solar and China-based Advanced Solar Power. In total, there are sixteen color BIPV technology suppliers profiled with details on products, power density, estimated power losses, and indicative pricing.
Standardization and other success factors
Standardization is one of the challenges for BIPV technologies, colored or not. It is a triple challenge because the panels must not only comply with IEC standards, but also building standards, such as EN 135011, and the safety glass standards. Since colored BIPV involves companies from both the PV industry and the glass industry it may require some additional collaboration.
“From our understanding, it should be a joint effort from all the PV and buildings stakeholders, particularly PV module manufacturers and façade makers, which both use safety glass. This joint effort will enable to increase the offer and volume and reduce the cost of colored PV façades,” Swiss researcher, Antonin Faes, told pv magazine.
The researchers stress that BIPV can compete on cost with classic high-quality building cladding materials, as an alternative cladding that provides the added benefit of electricity generation.
The review included a discussion of success factors, such as reliability and stability of color solutions, safety, and methodologies for quantitative color characterization. For example, it recommends “meticulous testing” of any new encapsulants and coatings to ensure that color changes or other forms of degradation do not take place, but also to establish safety against fire hazards.
Some of the other success factors include targeting mid-rise and low-rise buildings and early consideration of the impact on the bill of materials and installation processes.
In conclusion, the team pointed out the need to continue to address power loss concerns associated with colored PV but closed with a positive outlook about the “overall environmental and economic advantages” of BIPV and its potential to increase the surfaces available for energy production.
Looking ahead, Faes said that the group has seen an increasing interest in colored BIPV recently, pointing out that it is ten years since CSEM released the first white PV module. “The topic is very interesting as it takes place at the border of the objective PV system productivity and the subjective architect emotional rendering,” said Faes.
The review is available in the study “Colouring solutions for building integrated photovoltaic modules: A review,” published by Energy & Buildings.
Image: by Megasol Energy
This content is protected by copyright and may not be reused. If you want to cooperate with us and would like to reuse some of our content, please contact: editors@pv-magazine.com.
By submitting this form you agree to pv magazine using your data for the purposes of publishing your comment.
Your personal data will only be disclosed or otherwise transmitted to third parties for the purposes of spam filtering or if this is necessary for technical maintenance of the website. Any other transfer to third parties will not take place unless this is justified on the basis of applicable data protection regulations or if pv magazine is legally obliged to do so.
You may revoke this consent at any time with effect for the future, in which case your personal data will be deleted immediately. Otherwise, your data will be deleted if pv magazine has processed your request or the purpose of data storage is fulfilled.
Further information on data privacy can be found in our Data Protection Policy.