Solar water heater tank - has hemispherical absorber acting as storage vessel with matt black surface

摘要

The solar water heater consists of an outer transparent hemispherical shell (1) and an inner opaque hemisphere (5) which is the absorber, with a matt black surface. The two hemispheres are supported on a horizontal base (4) which in turn rests on an insulated bed (7). The volume (6) enclosed by the inner hemisphere is watertight and forms the hot water storage tank. The inside face (3) of the transparent outer shell (1) has a semi-reflective surface to reduce losses. Water under pressure is pumped into the storage vessel (6) through a feed pipe (8) whose outlet is below a perforated cover (5) which reduces turbulence. The water outlet (9) at the upper extremity of the storage vessel acts also as a safety relief valve.