A system for generating electricity comprising a turbine and a generator coupled to the turbine by a generator shaft so that an armature of the generator rotates when the turbine blades of the turbine are rotating, wherein rotation of the armature produces electricity. The system comprising a reservoir and a pressure sensor capable of providing a stream of signals corresponding to the pressure in the reservoir. The system selectively operating in one of a first operating mode, a second operating mode, a third operating mode, and a fourth operating mode. The mode of operation being selected based on a determination of the pressure in the reservoir.