Feb 21 2013
ElectraTherm, a leader in small-scale, waste heat to power generation, installed a Green Machine at a biogas plant in Straznice, Czech Republic. ElectraTherm, distributor GB Consulting and biogas plant constructor EnviTec commissioned an ElectraTherm Green Machine to generate additional power and increase energy efficiency on site, and the machine has accrued more than 2,800 hours with greater than 97% availability.
The Green Machine was added at a biogas power facility with a GE Jenbacher 412 internal combustion engine producing 844kWe. The installation of the Green Machine is the first of its kind to connect the machine at the beginning of the heat loop, providing the Green Machine with higher waste heat temperatures to increase power output, while maintaining proper heat input to the anaerobic digesters. The addition of the machine reduces the onsite electricity needed to reject excess heat through radiator fans. In combination with the electrical output of the Green Machine, this increases the plant efficiency by up to 8%.
ElectraTherm's patented organic Rankine cycle (ORC) technology begins with hot water entering the Green Machine at 94°C, where it heats a working fluid into a pressurized vapor. The high pressure vapor expands through ElectraTherm's patented twin screw power block, spinning an electric generator to produce approximately 40kWe at this site. After turning the expander, the vapor is condensed back into liquid through the use of a liquid loop radiator with some heat also being used for nearby district heating.
ElectraTherm's Green Machine generates fuel-free, emission free power from waste heat, on applications such as biogas, IC engines, biomass, geothermal/co-produced fluids and solar thermal. A fleet map is now available on the ElectraTherm website with details on individual applications, engines and links to case studies. The map is available at http://electratherm.com/case_studies/.
Source: http://www.electratherm.com/