Nearly 40 % of power usage in Europe goes to household heating and hot water. Current solar thermal collectors rely on expensive materials such as copper or aluminium, making widespread use unfeasible. The EU-funded POLYSOL project developed an alternative, more cost-effective solar thermal collector for domestic heating and hot water applications. The device comprises newly developed polymeric materials. Researchers tested a wide range of polymers before settling on a type of polycarbonate material as the polymer absorber. They created a 5-layer coating that showed a heat absorbance of 95 % and emmitance of 17 %, which is well beyond current solar collector performance. For the casing material, researchers selected two polymers that retained heat better than conventional plastics in testing. POLYSOL also modelled four theoretical solar thermal systems in three different locations to provide benchmarks for testing prototype solar thermal collectors. A prototype was then built and installed in several different locations for in-field testing. In parallel, the team conducted a market analysis and intellectual property assessment to prepare for product commercialisation. Low-cost POLYSOL solar thermal collectors are expected to provide significant incentive for consumers to invest in solar heating. This may also contribute to the EU's commitment to reducing its dependence on fossil fuels in the long term.
solar thermal collector, polymers, heating, hot water, polycarbonate