Constant temperature induced stresses in evacuated enclosures for high performance flat plate solar thermal collectors

AbstractA flat-plate solar thermal collector’s efficiency can be much improved if the enclosure in which the solar absorber is housed can be evacuated. This would result in a high performance, architecturally versatile solar thermal collector capable of supplying clean energy efficiently for use in applications including residential hot water and space heating. This paper focuses on the design of evacuated enclosures for flat-plate solar collectors, in which the solar absorber is completely surrounded by a thin layer (4–10mm) of thermally insulating vacuum, resulting in a thin solar thermal collector (depth