Water Heating; Solar Thermal
Water is by far the most common storage medium in solar domestic hot water systems. Rock storage is another method of sensible heat storage, but is not generally used in systems that are exclusively DHW. Storage of heat in solutions of phase-changing salts is extremely rare in DHVJ systems and therefore is not discussed.
Solar Thermal; Water Heating
Florida Solar Energy Center, "Solar DHW Storage Tanks And Systems" (2006). FSEC Energy Research Center®. 475.