Experimental methodology and thermal loss tests on small size absorber tubes for solar applications

Since the thermal energy for residential application is a relevant part of the entire demand, solar technologies could have an important role in decreasing fossil fuel consumption. A novel small parabolic trough collector is developed to satisfy heating and required hot water for a single house matching with a storage system. A new concept of the receiver is designed and a prototype is realized using two coaxial tubes (3 spattered layers). A covering glass with the vacuum inside complete the high tech component. Because of numerous innovation including the small size, a specific off-sun measurement procedure is set up with the aim of evaluating real thermal loss and heating the absorber by Joule effect directly. The novel test procedure is proposed for One-End absorber. The results of receiver performance are reported in vacuum condition and with air at ambient pressure.