Sunamp, a company based in East Lothian, is developing compact heat storage in heat batteries. These batteries will allow the intermittent output from renewable heat technologies such as Solar Thermal Panels, Heat Pumps, Biomass Boilers or supplies of waste heat to provide an output of heat when the user needs it. The company is currently carrying out a trial in seven houses owned by Berwickshire Housing Association. Tenants who are off the gas grid and who had their heating system converted from electric storage radiators to air source heat pumps had found their financial savings were only modest as a result of no longer being able to use off peak electricity. However, by using a heat battery in conjunction with an air source heat pump it is hoped that tenants can resume the use of cheaper off peak electricity, and thus boost savings.