Abstract: A modular power plant operating from a source of geothermal fluid that produces geothermal steam containing non-condensable gases such as hydrogen sulfide, and geothermal brine, includes a steam module and an organic fluid module. The steam module has a steam turbine coupled to a generator for expanding the geothermal steam and producing electrical power, low pressure steam, and condensed steam.

Abstract: The present invention provides a method of and apparatus for controlling the operation of a valve that regulates the flow of geothermal fluid that comprises geothermal brine and steam flowing through the valve to a geothermal plant. The method includes determining the maximum permitted value of at least one parameter or quantity affecting the operation of the geothermal plant, and setting a predetermined value for the at least one quantity which is less than the maximum value of the quantity. The flow of fluid through the valve is reduced when the value of said at least one quantity reaches its preset value for maintaining the operation of the geothermal plant.