Multi-mode RCCI (Reactivity-Controlled Compression Ignition), a promising advanced combustion process, has the potential to improve fuel economy of passenger cars by at least 15%, according to a recent study performed by a team at Oak Ridge National Laboratory, supported by EERE’s Vehicle Technologies Office (VTO).  The technology could also potentially reduce the engine’s NOx emissions that contribute to smog by 17-21% compared to traditional light-duty diesel engines. 

Multi-mode RCCI is a form of low-temperature combustion that uses injections of both gasoline and diesel fuel in an internal combustion engine whenever possible. For this study, researchers collected RCCI data using an experimental engine and compared it to a baseline 2009 gasoline, port-fuel injected engine.

RCCI was originally developed at the University of Wisconsin-Madison Engine Research Center laboratories with VTO support.  Use of this multi-fuel technology allows more control over the combustion process than conventional, single-fuel internal combustion engines   When RCCI is combined with other advanced combustion strategies, the potential for energy savings is even greater. 

EERE’s Vehicle Technologies Office (VTO) develops and deploys efficient and environmentally friendly highway transportation technologies that will enable America to use less petroleum. These technologies will provide Americans with greater freedom of mobility and energy security, while lowering costs and reducing impacts on the environment. Learn more about the research and development on advanced combustion engines supported by the Vehicle Technologies Office.

The Office of Energy Efficiency and Renewable Energy (EERE) success stories highlight the positive impact of its work with businesses, industry partners, universities, research labs, and other entities.