| 摘要 |
<p>Apparatus (300)for storing energy, comprising: a first engine stage (330)acting as a compressor during a charging phase of a cycle and as an expander during a discharging phase; a first heat store (320)for receiving and storing thermal energy from gas compressed by the first engine stage (330)during the charging phase; a second engine stage (340)acting as an expander during the charging phase to expand gas received from the first heat store (320)and as a compressor during the discharging phase; a second heat store (310)for transferring thermal energy to gas expanded by the expander (340)during the charging phase; a heat rejection device (385/380)for dissipating unwanted heat from a gas flow; and control means (370)for varying the degree of thermal coupling between the gas flow and the heat rejection device,or,its level of heat rejection performance,between a lower level during a first part of the cycle (e.g. a discharging phase) and a higher level during a second part of the cycle(e.g. a charging phase), so as to increase heat rejection during the second part (such that during charging gas enters the second heat store at a lowered temperature)for boosting energy density over the complete (e.g. charge/discharge) cycle.</p> |
