This system is a layered storage unit utilizing two phases: water and steam. Heat is drawn off above the waterline in the steam zone, supplying various consumers. An expansion vessel is not required, as the waterline naturally adjusts to temperature induced volume changes. For low-temperature domestic applications (heating, hot water), a 1000 liter tank is designed, capable of being charged up to 145°C. Spherical tanks for higher temperature applications, such as cooking, cooling, process heat, or district heating, are also available. Charging is performed via a heating element powered by saturated steam from the solar collector system. Condensate is returned to the collectors.