Integrating Heat Pumps with Novel Solar Thermal Collectors to Decarbonise Space and Water Heating

Our project will help reduce operational costs associated with space and water heating and will help decarbonise heat. Our proposal is to integrate our novel solar thermal innovation with air source heat pumps to provide space and water heating. Our innovation allows our solar thermal panels to freeze without damage eliminating the requirement for antifreeze. This means we can use water as the heat exchange fluid and design larger systems without being size constrained. Our system can overheat safely allowing larger arrays without the corresponding large water storage required to prevent overheating. Existing systems that use antifreeze are sized so that they never overheat as the antifreeze degrades and requires replacement. This means that the system is sized for the sunniest day of the year and matched with the available water storage and is undersized for most of the year. In the UK a 4.5 sqm evacuated tube collector (30 evacuated tubes) would require around 250 litres of water to prevent it overheating in summer. As our system uses water as the heat exchange fluid we can allow it to overheat, have larger arrays and get useful energy throughout the year that can contribute to space heating when it is needed in the cooler months. We have proven this innovation with 20 sqm of evacuated tube collector but with only 200 litre of water storage on a dairy farm. If this was an antifreeze type system it would require 1,200 litres of water storage to prevent overheating in summer. This would be costly and impractical to implement in most cases.