Organic Rankine Cycles (ORC) are systems that can effectively recover low-grade heat for electric power generation. For ORC to be a viable technology, it should operate safely and efficiently under variable operating conditions due to exogenous and operating specifications changes.

The efficiency of current high temperature Organic Rankine Cycles does not exceed 24%. Typical steam Rankine cycles show a thermal efficiency higher than 30%, but with a more complex cycle design (in terms of number of components or size).

ORC: How it works In a typical ORC design, a thermal energy source feeds an evaporator to drive an expander or “reverse compressor”, which in turn generates the electricity. The provider of the heat can be natural, such as in the case of geothermal energy, or waste heat from any number of industrial waste heat sources.

The organic Rankine cycle is a modification of the traditional steam Rankine cycle (SRC) that is the basis for most of the central station power generation in the U.S. Instead of steam, ORCs use organic compounds that have better generation efficiencies at lower heat-source temperatures as the working fluid.

ORC is a closed cycle process like a conventional steam cycle process, in which waste heat is used to evaporate an organic fluid. Through an expander this drives a generator to produce clean energy. ORC captures lost profit by using low and mid temperature waste heat sources that most companies aren't aware of.