Patent ID: 8826664
Filing Date: 2014-09-09
Classification: F01K

Abstract:
1. Apparatus for storing energy, comprising: a compression chamber configured to receive a gas; a compressor configured to compress gas contained in the compression chamber; a first thermal store comprising a gas-permeable structure and configured to receive and store thermal energy from gas compressed by the compressor; an expansion chamber configured to receive gas after exposure to the first thermal store; an expander configured to expand gas received in the expansion chamber; and a second thermal store comprising a gas-permeable structure and configured to transfer thermal energy to gas expanded by the expander, wherein the first and second thermal stores are separate from the compression and expansion chambers, respectively, and wherein the apparatus is configured such that the first and second thermal stores are placed within a thermal heat pump cycle such that a flow path of the expanded or compressed gas passes through the gas-permeable structure of each of the first and second thermal stores for receiving and storing thermal energy from the gas in the gas-permeable structure of the first thermal store and for transfer of thermal energy from the gas-permeable structure of the second thermal store to the gas, respectively, the thermal energy transfer to or from the expanded or compressed gas being a substantially isobaric heat transfer.