Power generation constitutes 20-25% of CO2 emissions and is therefore a focus for attempts to reduce such emissions. The global solar energy resource is about one thousand times larger than any other carbon-free energy source. The additional annual demand for carbon-free energy could, for example, be provided by just 1.5 hours of global irradiation from the sun. However, sunlight has to be converted into a useable energy form at a reasonable cost. Building Integrated Photovoltaics (BIPV) is one of the most promising technologies for achieving this. Photovoltaic (PV) technologies have shown an impressive exponential growth of approximately 40% per year during the last decade.
The overall objective of the DYEMOND SOLAR project was to demonstrate a cost-effective means of producing transparent Dye-Sensitised Cells (DSCs), based on a patented technology that uses one-dimensional photonic crystals (1DPCs) to improve the efficiency and colour of solar cells. The demonstrated prototype production system will be a pre-industrial-scale system, i.e. a fully functional production line, which will serve as a base model for an industrial-scale operation.
The DYEMOND SOLAR project proved the production potential and scalability of screen printing as a production method for manufacturing Dye-Sensitised Solar Cells (DSCs). This solar technology in combination with the chosen production method is sustainable and environmentally friendly, with no toxic emissions. The costs of producing DSCs using the project technology were calculated to be no higher than €80/m2 (the foreseen cost target). The originally foreseen ultrasonic technology, which project beneficiary NLAB Solar had developed to spray coat DSCs, was deemed unsuitable at the pilot stage and replaced with a screen-printing method. The changing of the substrate and electrolytic substance was found to greatly increase the efficiency of the solar cells. The costs of the new substrates and electrolytic material used after the improvement is essentially lower that the price of the originally planned ones. The project team successfully identified and utilised the newest component innovations in their solar cell development, for example, demonstrating and selecting the most effect substrate and inks. The DSC's were successfully manufactured during the project, meeting the production target of 50m2 per day.
The project established monitoring protocols, for example, measuring humidity, temperature, machinery performance, and power density of the solar cells. Accelerated life-time tests showed less than 10% loss of electrolyte. Overall, the project demonstrated a sustainable product, with a production yield of over 90%. A report of the demonstration process was used to further improve the pilot facility. Project outputs, including a report on the technical specifications and pilot plant performance, ensure that the technology can be readily up-scaled and replicated in other EU Member States and regions. Both the innovation and demonstration value of the project are therefore very high. The project team were able to introduce a new DSC technology and test its usefulness, and evaluate both the economic and environmental benefits that can be gained. Success criteria were elaborated for the new NLAB Solar technology, which took into account design and performance. The DSC solar panels are lightweight, customisable, and can be assembled to form large homogeneous surfaces. The design is unique, with the solar cells constructed using a completely new patented architecture. This allows for the elimination of the current collectors seen in other technologies. Furthermore, using screen-printing as a production method enables the manufacturing of solar cells in a variety of colours, shapes, with logos and on any material. Using screen printing, which is an established, low-cost and simple production technology, enables lower energy to be embodied in the production process - with an energy payback time of less than one year. There is no use of scarce or toxic raw materials, and no toxic emissions from manufacturing, which makes the production of DSC’s truly environmentally-friendly. In terms of performance, the advantages of DSCs include a high indoor power density, stable efficiencies in all light conditions, they are less sensitive to the angle of incident light than comparable technologies, and have higher efficiency than competing technologies at higher working temperatures. These characteristics make the DSCs ideal for a variety of real-life situations, including applications where even output is preferable.
Environmental benefits arise from the solar cells producing energy without contributing to CO2 emissions, so mitigating climate change where the technology replaces fossil fuels. A large part of the material (more than 50%) used in solar cells is recyclable after the cells have reached the end of their life span, which is estimated to be around eight years, depending on the technical application.
Significant socio-economic effects will be tangible if the innovative dye-sensitised solar cells and panels gain acceptability in the market and reduce the price of solar energy. World Energy Outlook 2014 shows nearly 1.3 billion people are without access to electricity and 2.7 billion people rely on the traditional use of biomass for cooking, which causes harmful indoor air pollution. These people live mainly in rural areas, in either developing Asia or sub- Saharan Africa. Each year, 4.3 million premature deaths can be attributed to household air pollution resulting from the traditional use of solid fuels, such as fuel wood and charcoal. Micro-installations, which would be more accessible with the project’s lightweight solar cells than with traditional silicon glass modules, could serve to reduce deaths associated with use of traditional solid fuels, as the project’s DSCs become more readily available for all.
Further information on the project can be found in the project's layman report and After-LIFE Communication Plan (see "Read more" section).