Combined short and long term heat storage with Sodium Acetat Trihydrate in cylindrical tanks

A cylindrical heat storage prototype was designed to utilize Sodium Acetate Trihydrate (SAT) for combined short and long term heat storage. It was manufactured with inexpensive standard components of water stores. It contained 150 liter of SAT composite and 55 l of water. A heat storage test facility was used to investigate if the concept of stable supercooling of SAT can be applied and if thermal power during discharge is sufficient for domestic heat supply.

Preliminary results showed that 27 kWh of heat can be stored during heat up to 90°C, which is significantly higher than water heat stores of the same volume. After a heat loss free storage period, 11 kWh (long term storage potential) were discharged during SAT composite solidification. Parallel application of heat storage units should be investigated to overcome heat transfer limitations.