New CHP motor brings 20% efficiency boost
Tests have demonstrated that a residential combined heat and power (CHP) motor developed as an Advanced Research Projects Agency - Energy (ARPA-E) backed venture through the Generators for Small Electrical and Thermal Systems (GENSETS) program offers at least a 20% improvement in efficiency over the current leading alternatives.
The single-cylinder motor, which runs on natural gas (NG), has been developed by a consortium led by MAHLE Powertrain. It features the specialist's low friction technology and manufacturing techniques, including the new MJI (MAHLE Jet Ignition) pre-chamber ignition technology.
MAHLE Powertrain is supported in the project, which was announced in November 2015, by Oak Ridge National Laboratory, Louthan Engineering, Kohler Company and Intellichoice Energy.
'Electricity generated at the point of use is an effective way of combating the inefficiencies of centrally produced power,' said Mike Bunce, head of research for MAHLE Powertrain LLC and principal investigator on the project. 'CHP motors are a perfect solution for generating electricity and harnessing otherwise wasted energy for heating, for both primary power and heat generation or for use on an ad hoc basis during power outages. However, this technology has previously been cost prohibitive, inefficient and displayed suboptimal reliability characteristics. In testing, the 1kWe micro-CHP motor achieved 33% Electrical Conversion Efficiency; 20% more than the current leading unit in this power class.'
The single-cylinder CHP utilizes technology and automotive engineering principles already proven by MAHLE Powertrain's work for major vehicle manufacturers. For example, MJI extends traditional limits of lean combustion to maintain lower gas temperatures and therefore reduce harmful NOx formation. This simplicity of design and manufacturing will reduce cost and increase durability.