| Abstract |
This paper describes the technologies and field proven experience with various geothermal binary and combined steam/binary power plants utilizing both water and steam dominated resources having low, moderate or high enthalpy. The key to an economic and successful project is the cost effectiveness of the complete plant, as measured in the actual cost of production. Only proven technologies can effectively produce reliable electricity at a predictable cost to the project developers, operators and investors. In geothermal flashed steam plants, many innovative power cycles have been proposed in the last 20 years; but only four are in proven commercial operation, these are: single- and double-flash steam cycle, the super-critical binary, the cascade binary and the combined steam and binary. Operational experience has confirmed the advantages of the binary plants, not only for the low enthalpy water-dominated resources, but also at high enthalpy, or in case of aggressive brine, for low environmental impact and for long term resource management considerations. The implementation of new geothermal plants still faces hurdles, in particular in financing. |