NOVELTY - A solar heat collector comprises a transparent envelope (10); a collecting element for collecting heat from sunlight; a pipe for receiving heat collected by the collecting element and for circulation of a heat transfer fluid; and plate(s) fluid-tightly attached to the envelope. The plate is attached to the envelope by an adhesive.    USE - For collecting solar heat for domestic purposes, e.g. a domestic hot water supply, central heating, swimming pool heating or air conditioning; or as a source of industrial process heat, e.g. for water desalination.    ADVANTAGE - The inventive solar heat collector is inherently cheap to manufacture due to its value engineered design and use of modern commercially available materials and adhesives. A combination of low cost with high efficiency results in a shorter financial payback period.    DETAILED DESCRIPTION - A solar heat collector comprises an envelope (10) of transparent material; a collecting element within the envelope for collecting heat from sunlight; a pipe (14) extending through the envelope for receiving heat collected by the collecting element and for circulation of a heat transfer fluid; and plate(s) fluid-tightly attached to the envelope and having fluid-tight joint(s) with the pipe via which the pipe passes into and/or from the envelope. The space (26) within the envelope is at a pressure such that there is substantially no convective heat transfer from the collecting element to the envelope. The plate is attached to the envelope by an adhesive.    An INDEPENDENT CLAIM is included for a method of manufacturing a solar heat collector comprising attaching to one face of a plate-like collecting element, a generally U-shaped pipe for receiving heat collected by the collecting element and for circulation of a heat transfer fluid; gas-tightly attaching the ends of the pipe to a cap at apertures in the cap; inserting the collecting element and the pipe into an interior space of an envelope of transparent material and gas tightly attaching the cap to the envelope; reducing the pressure within the envelope to a value such that there is substantially no convective heat transfer from the collecting element to the envelope; and forming a gas-tight seal to preserve the reduced pressure in the interior space of the collector.    DESCRIPTION OF DRAWING(S) - The figure shows a diagrammatic view of a solar heat collector in longitudinal section and viewed from the normally concealed side.    Envelope (10)    Pipe (14)    End caps (18)    Space (26)