Patent ID: 8234863
Filing Date: 2012-08-07
Classification: F22B

Abstract:
1. A compressed-gas energy storage and recovery system comprising: a cylinder assembly for at least one of compressing gas to store energy or expanding gas to recover energy; a movable boundary mechanism separating the cylinder assembly into two chambers; a crankshaft, mechanically coupled to the boundary mechanism, for converting reciprocal motion of the boundary mechanism into rotary motion; a heat-transfer mechanism, comprising a plurality of nozzles, for introducing heat-transfer fluid within a chamber of the cylinder assembly to exchange heat with gas therein, thereby increasing efficiency of the energy storage and recovery; an actuating mechanism for controlling a number of active nozzles introducing heat-transfer fluid within the chamber during a single cycle of compression or expansion of gas, the actuating mechanism comprising a plurality of valves and a control system for controlling the valves based at least on a pressure within the cylinder assembly; and a sensor for measuring the pressure within the cylinder assembly, the control system being responsive to the sensor, wherein the plurality of nozzles is organized into at least two nozzle groups, at least one nozzle group not being active during a portion of the single cycle of compression or expansion.