Innovative solar window is a win for energy efficiency
When it comes to going carbon-neutral by 2050 and reducing our dependence on fossil fuels, Europe has a building problem. That’s because Europe’s building stock is responsible for 40 % of the EU’s total energy consumption and 36 % of all greenhouse gas emissions. If Europe is to achieve the goals of the European Green Deal, it must make its buildings more energy-efficient. For the EU-funded Solar-Win project, the place to start is the windows. “The amount of heat that comes in and out of a window is responsible for between 25 % and 30 % of a typical home’s heating and cooling energy use,” says Victor Izquierdo, deputy head of solar energy materials and systems at www.irec.cat (IREC), a centre of excellence in applied energy research and one of the project’s lead partners. Not only did the project create a more energy-efficient window, it also turned windows into a source of clean energy. “Our main objective was to bring to market an innovative photovoltaic window solution capable of functioning both as a traditional window and as a solar panel,” explains Izquierdo. But, as we all know, solar panels are opaque and not very conducive to filling a building with bright sunshine. “This is where our solution really ‘shines’,” adds Izquierdo. “Unlike current solutions, the SolarWin PV window is completely colourless and visually appealing.”
From light to electricity
Even though it may not look like a solar panel, the window generates power in a similar way. This is possible thanks to an innovative coating technology developed by PHYSEE, a sustainable technology company, that collects some of the light passing through the window. The coating transfers the collected light to the edges of the window, which are lined with a copper indium gallium selenide (CIGS)-based flexible PV stripe created by SunPlugged. This stripe transforms the light into useful electricity. Furthermore, the windows are designed so they can be installed in both new and retrofitted buildings, thus supporting the EU’s Energy Performance of Buildings Directive and its Renovation Wave initiative. “Any conventional window can be easily replaced with a SolarWin PV window without a significant cost increase and without the need for extra integration work,” he notes. According to Izquierdo, the project’s success is the result of strong collaboration amongst the various partners. “By combining PHYSEE’s smart window technology, SunPlugged’s flexible PV foils, and www.acciona.com (ACCIONA’s) construction prowess with IREC’s research expertise, we were able to quickly build a solution that will contribute to the EU’s transition towards decarbonisation.”
A new clean energy generation technology
In addition to taking the SolarWin PV window to the pre-commercial stage, the project also helped advance each of the individual partner’s products and solutions. For example, the project helped optimise SunPlugged’s production process so it could produce its PV technology more cost-effectively and at scale. The project also developed a next-generation in-line process monitoring technology compatible with Industry 4.0 concepts. The technology can be used to further increase production efficiency on PV lines while also decreasing the amount of industrial waste. “The net result of our work is both the introduction of new clean energy generation technology and a sustainable method for producing it,” concludes Izquierdo. With the project now complete, the partners are working to scale up production and bring the various solutions to market.
Keywords
Solar-Win, solar window, energy efficiency, solar panel, European Green Deal, building stock, Energy Performance of Buildings Directive, Renovation Wave