Abstract This paper presents the performance of a transpired solar collector (TSC) used as a preheater for an air to air heat pump, installed in a demonstration house in Wales, UK. The TSC is activated when there is a demand for both heating and ventilation. The system is designed to be aesthetically pleasing, affordable, and can be installed on south facades/roofs in new and retrofit buildings. A TSC has been monitored for one year at a demonstration house and data normalised using historic weather data. Results show the system contributed 15% of the heating and hot water demand (1360kWh) in one year. In 2017 UK figures this translates into 100GBP to 200GBP savings per year compared to a conventional heating source. The total cost of the TSC technology for a mature market is projected to be less than 1600GBP for the installed area which indicates that the payback could be less than 8 years.