Advanced Electrical Power Generation Technology Using Renewable & Clean Low-Enthalpy Geothermal Energy Sources

Advanced nonconventional renewable & clean energy technologies which are used for generation of electricity have shown real promise and received renewed interest in recent years due to an increasing concern of environmental issues of greenhouse gas (GHG) emissions responsible for global warming effects, environmental pollution, and the limitations and conservation of natural energy resources. One of these innovative emerging technologies includes renewable low-enthalpy geothermal energy sources for clean electrical power generation. This promising technology offers potential applications in generation of electric power which can be produced using renewable low-enthalpy geothermal energy resources available in many parts of the world. In this paper, the basic concept of Organic Rankine Cycle (ORC) binary power technology using low-enthalpy geothermal heat sources is introduced and its potential applications and limitations for small-scale geothermal power generation and its relevant environmental and economic considerations are presented and discussed. Also, some recent developments and patents related to the energy conversion of low-enthalpy geothermal energy into electrical power with their important and relevant applications are reviewed. The list of patents reviewed here is by no means supposed to be thorough or complete but demonstrates, however, evolution trends related to low-enthalpy power generation.