Dutch video, English subs
TNO and TU/e have developed a brand new device principle and a breakthrough material, in which the heat is stored. Together they form the heat battery. It is so small that it fits into the limited space available in most homes. The breakthrough material is a salt composite, with K2CO3 (potassium carbonate) as the base material.
The heat battery uses a so-called thermochemical principle. The heat battery for the home is based on two components: water and a salt hydrate. As soon as water vapour and salt are added, the water binds to the salt and the salt transforms into a new crystalline form. This reaction that releases heat is reversible. When heat is added to separate the water from the new crystal, the two original components are obtained again. In fact, it is this heat that is stored, and as long as these two components are separated, the stored heat is retained. This makes it a process without heat loss, which in turn is a prerequisite for long-term storage of heat. In this way a lot of heat can be stored in a small volume. Significantly more than water, and considerably more than in so-called phase transition materials.
The battery can store both heat and electricity. It has the size of a small refrigerator, expected consumer price 3,000-6,000 euro. Technical life expectancy 20 year. Storage capacity device: 200-300 MJ (600 MJ/m3). Power: 1-3 kW. The battery has 4 parts: ventilator, heat exchanger, condensor and reactor vessel:
The heat capacity is at least ten times higher than that of water and more than phase-change-based devices.
The European Commission has granted a 7 million euro subsidy for further development of the TNO and TUE heat battery, within the Horizon2020 framework. For that purpose a new European consortium named HEAT-INSYDE, led by TNO and TUE, will develop the heat battery for the consumer market.
[ec.europa.eu] – Horizon2020
[source] Prototype heat battery