US Patent 8680704 Wellhead pressure reduction and electrical power generation

Apparatus and method for generating electrical power through the reduction of a wellhead pressure. In accordance with various embodiments, a wellhead coupled to a subterranean formation supplies a first conduit with pressurized natural gas at a first pressure. A turbine receives the pressurized natural gas and induces a pressure drop in the gas as the gas induces mechanical rotation of the turbine. A mechanical linkage is coupled to the turbine, and an electrical generator is coupled to the mechanical linkage. The electrical generator generates electrical power responsive to the mechanical rotation of the turbine. The turbine and the electrical generator are operated to maintain an exit pressure of the pressurized natural gas at a predetermined second pressure less than the first pressure.