Field testing of ORC processes
|Location||Development and planning in Oberhausen and Ingelheim; realisation at 6 CHP plant sites of project partners|
|Project plan||Continuation of process development; realisation of 5 more ORC field systems at 3 sites; subsequent monitoring with analysis of results in service|
|Developer, organizer||Fraunhofer UMSICHT, Oberhausen; Cyplan Ltd., Ingelheim|
The Organic Rankine Cycle (ORC) is an operating process for steam turbines that uses a working medium other than water vapour. An organic substance with a low boiling point is used in place of water as the working fluid. This process is mainly used where the temperature difference available between the heat source and the heat sink is too low to operate a turbine driven by water vapour. With ORC systems, it is possible to convert thermal energy from small-scale sources – e.g. waste heat, geothermal energy, biomass or solar thermal sources – into electrical energy in an economically viable manner.
Waste heat from CHP plants is released to the surroundings without being harnessed at many CHP plant sites in the renewable energy sector (biogas, vegetable oil, sewage gas, landfill gas, coalmine gas). ORC processes can be used to convert previously unharnessed waste heat into valuable effective energy in the form of electricity. The ORC can also be operated in cogeneration mode. The goal of this project is to use ORC processes to generate between 20 and 120 kWel of additional electricity from the heat contained in exhaust gases and cooling water from motor CHP plants and, in doing so, to improve the energy balance of these motors.
With their relatively short payback times of between 3 and 6 years, standardised, small-scale ORC processes – implemented in the form of ORC modules – are commercially viable for CHP plant operators if the production costs are low enough. Operators can invest directly in these systems, which are also attractive for energy service companies in the context of waste heat contracting agreements. All of the additional electricity generated as compared to the initial state without generation using waste heat can be treated as a gain from a climate protection viewpoint.
The eight ORC field systems for power generation using waste heat that were installed at six sites as part of this project will be subject to subsequent operation monitoring for a period of five years.
|Electrical efficiency of motor||40,00||45,00||%|
|Total project costs||4,50||Mio. Euro|
|Planning costs||1,40||Mio. Euro|
|Annual electricity credit||1.500,00||Euro/kWel,ORC|
|CO2 emissions of pilot systems||2.800,00||t/a|
|Primary energy reduction costs for pilot systems (after taking all development costs into account)||5,00||Cent/kWhel|
|Primary energy reduction costs in commercial operation (estimate)||2,50||Cent/kWhel|