Engineering Aspects of a Novel High Efficiency Reciprocating Internal Combustion Engine

A new type of high efficiency reciprocating internal combustion engine, which is predicted to achieve an electrical efficiency of up to 60% on diesel fuel or 58% on natural gas, is described with particular focus on the engineering of its novel components. The so-called isoengine, which is being developed by Innogy plc, involves quasi-isothermal compression of combustion air. In commercial applications it is envisaged that the engine will run at 600 rpm and produce 7 MW of electric power. The engine will also be capable of producing up to 3 MW of heat in the form of hot water, with the electrical efficiency reduced by two percentage points. The engine is intended for distributed and on-site power generation with the option of switchable co-generation of hot water for industrial use or for space heating. A 3 MW_e engineering demonstrator is currently under construction.