Bloomfield engine developer LiquidPiston Inc. has devised a rotary diesel engine that it claims is lighter, more fuel efficient and quieter than conventional diesels found mostly in heavy trucks and off-road equipment and some cars.
LiquidPiston said its lightweight X2 engine is a 40-horsepower rotary engine that requires no valves, cooling systems, radiators, mufflers, or other components.
To drum up automotive interest and to search for a partner eager to invest in its refinement, the X2 was unveiled Wednesday at the Directions in Engine-Efficiency and Emissions Research conference in Dearborn, Mich. It also will displayed at the Engine Expo, in Novi, Mich., which runs next Tuesday through Thursday, the company said.
The company, which raised $5 million in 2011 from private investors Northwater Capital and Adams Capital Management, says it's currently test firing an alpha prototype of the X-series engine called the X1. The X2 engine will be available as a beta prototype for outside testing by the first quarter of 2013.
Marrying diesel technology with rotary-engine technology appears to break new ground in the scramble among the world's vehicle makers to deliver more energy-efficient vehicles, be they internal-combustion or electric propelled, or a hybrid of both.
Until now, only a handful of carmakers have attempted to refine gasoline-powered, rotary-engine technology, and only one – Mazda – ever introduced one to the mass market with its former RX-7 and RX-8 sports cars.
Diesels are gaining among a growing number of car and truck buyers who covet the internal combustion engine's high fuel mileage.
New federally mandated diesel-fuel formulations, while pricey at the pump, have eliminated much of the exhaust soot and smell associated with older diesel-engine technology.
LiquidPiston said the X2 operates on its patent-pending "high-efficiency hybrid cycle" for greater fuel efficiency. It said the HEHC cycle increases average efficiency over conventional diesel engines from less than 20 percent to more than 50 percent under normal operating conditions, reducing fuel consumption by as much as threefold over conventional diesel engines.
By combining its HEHC with a rotary engine architecture, LiquidPiston said it has created an engine that is up to 10 times lighter, whisper quiet, and two to three times more efficient at part-load than conventional diesels.