Innovative low-concentration PV technology
To decrease PV electricity generation costs, the solar energy industry was forced to implement innovative solutions for large-scale PV deployment. These should essentially include low capital cost, short energy payback, long system lifetime and system flexibility. The SOLGAIN (Competitive stationary low concentrating solar module of novel design) consortium was set up to address economic, environmental and technological obstacles by developing novel stationary LCPV designs. The target was to achieve EUR 0.67 per watt and optimise module assembly for commercial applications. Compared to high-concentration systems, LCPVs are easier and cheaper to manufacture and maintain. In addition, they are particularly suitable for building integration, offering a competitive alternative to flat PV systems. Compound parabolic concentrators and prism-based concentrators are some examples of LCPV systems. Researchers successfully designed an LCPV system with a prism-coupled compound parabola concentrator of wide acceptance angle that should maximise annual energy production. By using a transparent dielectric nanocomposite material with high refractive index, they eliminated the need for mechanical solar tracking. Finally, researchers used a high-efficiency back-side interdigitated copper contact solar cell to optimise performance, eliminate shading losses and cut down costs. Development of these innovative LCPVs has high potential to meet energy demands during peak hours. This due to their wide acceptance angle and their ability to capture a large part of the diffuse solar radiation in addition to the direct component. The thin-film PV module reduces the amount of active material. This has a great impact on the energy payback time, estimated to be less than a year. Researchers designed the LCPV modules with flexibility in mind. These modules can replace conventional building materials in parts of the building envelope – especially in vertical facades. Enhancing cell energy conversion efficiency while decreasing its installation cost and using less active material should facilitate developing cost-effective modules. SOLGAIN prototypes should enable higher conversion efficiencies and five-fold active material reduction – both leading to significant cost performance.
Keywords
Low-concentration photovoltaic, solar energy, energy payback, SOLGAIN, building integration