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Isentropic Ltd announces successful testing of its layered thermal store prototype

Segensworth, Hampshire, England, 23 November 2015: Isentropic Ltd, which is developing a stand-alone electrical energy storage system called Pumped Heat Electricity Storage (PHES), has conducted tests successfully validating its highly efficient, novel, thermal store concept.
James Macnaghten, CEO of Isentropic Ltd, says: “We have built and tested two thermal stores with 12 tons and 26 tons of storage media respectively. Our results demonstrate the concept and confirm theoretical predictions giving a storage efficiency of 98.5%.”
The Isentropic® Thermal Store is an enhancement of a packed bed store, which subdivides the store into a number of layers. Valves are used to select the layers at which gas enters and leaves the store, restricting gas flow to the part of the store in which store material is actively being heated or cooled. Non-active parts of the store are bypassed.
Since only the thermally active part of the store is exposed to gas flow, pressure drop through the store is significantly reduced. This allows the use of smaller particles than would conventionally be selected. Smaller particles have much better heating and cooling characteristics than larger particles and so the efficiency of the process is increased.
The subdivision of the store into actively controlled layers also allows precise control of the heat exchange process and allows the active part of the store to be much smaller than in a simple, unlayered store. This makes the fraction of the store available for full heating and cooling cycles proportionally bigger, resulting in greater heat storage capacity for a given size of store in conjunction with improved efficiency.
Click here for an animation of the Isentropic® Thermal Store test video
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