SINTEF and COWA develop compact salthydrate heat battery for homes

Researchers at SINTEF and the Swiss company COWA Thermal Solutions have developed a compact salthydrate-based thermal storage unit (a “heat battery”) suitable for private homes.

• Main announcement/action: The research team (SINTEF in Norway and COWA Thermal Solutions in Switzerland) developed a salthydrate-based thermal battery that stores surplus heat from heat pumps for later use; it can be up to four times smaller than a traditional hot water tank and is intended for private-home use. The work is part of the EU-funded Sure2Coat project (14 partners across 7 European countries).
• Technical and project details: The system uses salthydrates as phase-change material and thin recycled-aluminium cooling fins protected by a Plasma Electrolytic Oxidation coating. In tests, researchers raised battery efficiency from 65% to 85%, reduced charging time by over 70%, and cut heat delivery time by over 80%. COWA developed salthydrate formulations with additives for long-term stability while SINTEF improved heat-transfer and system efficiency.