Vacuum flat plate solar thermal systems offer advantages over both vacuum tube systems by collecting a greater fraction of the available solar resource and flat plate systems by allowing higher temperatures to be achieved with better efficiency. The vacuum envelope if at a pressure of less than 0.1Pa effectively suppresses gaseous conduction and convection allowing thin panels to be developed with increased suitability for building envelope integration.
Solar energy availability and thus solar thermal heat generation is often out of phase with heat demand for water or space heating, requiring effective thermal storage to allow demands to be met.
In this project designs for durable vacuum flat plate systems will be developed and prototype laboratory scale systems produced for performance evaluation. A detailed model of vacuum plate solar systems linked to different types of thermal storage will be developed. This model will allow different options and approaches for thermal storage, sensible, latent and thermochemical to be simulated to assess the level of solar savings fractions that can be achieved for a range of representative hot water and space heating loads. Prototype stores will be developed and characterised in the lab before outdoor testing of an integrated system comprising vacuum flat plate collector and thermal store.