Any thermoelectrical plant is inherently inefficient due to the high heat of vaporization of water.
Several factors enter into determining the boiling point, and the molar heat of vaporization, of a hydrocarbon.
In response to fluid production the liquid phase will boil, with heat of vaporization supplied by the reservoir rocks.
heat of vaporization in Science
heat of vaporization The amount of heat required to convert a liquid into a gas at constant temperature and pressure. A gas releases the same amount of heat when it becomes liquid. Compare heat of fusion.