A solar-powered chiller that can also function as a heat pump and operate almost entirely without any other power source has been developed by researchers in Europe.
The VTT Technical Research Centre of Finland and German company ZAE Bayern partnered for the project, with a 10 kilowatt system piloted in both Finland and Germany.
The basic proposition is that cooling is needed when the sun is shining, which is also when solar energy is generated.
The solar-powered absorption chiller works like a gas refrigerator, using a solar thermal collector instead of gas. Electricity is needed for the flow pumps, but the researchers found this can be supplied by district heating, biofuel boilers or industrial process heat.
The chiller also works as a heat pump for winter heating.
Finnish company Savo-Solar also participated in the pilot project, operating the system for both heating and cooling of its head office.
The testing showed that for the technology to be used for heating as well as cooling, to be economically viable and competitive the system would need to be 50kW or bigger.
Examples of large, megawatt-class absorption chillers based on district heating can already be found in Helsinki and Turku in Finland, the researchers said.
Following the successful trial, the solar company and ZAE Bayern now aim to develop a commercial version.