Advanced Binary Cycles in the Geothermal Industry

Abstract

The binary cycle, in the form of the Organic Rankine Cycle (ORC), has become a common means of utilizing low to moderate enthalpy heat sources in the geothermal industry over the last two decades. It has been widely used to utilize the brine in an existing single flash plant and in many other locations it is used as an efficient and reliable way of working with the geothermal resource, in the form of brine only or brine and low pressure steam coming from a separator. Over the years the basic ORC has been improved and modified to better adjust the cycle to various conditions of the heat source. In this paper we will describe some advanced versions of the Organic Rankine Cycle and will demonstrate its means of providing an efficient solution for specific thermodynamic and chemical properties of geothermal fluid sources.