Volume 8: Advances in Energy Innovation and Development

Biofuels with Tailored Properties (A) for Hybrid and Plug-in Electric Vehicles(B) Doris Oke, Jennifer B. Dunn*, Greg Zaimes, Doug Longman, Hao Cai, Lauren Sittler, Emily Newes, Aaron Brooker, Ram Vijayagopal, Troy Hawkins, Scott Curran

Abstract

For the past five years, the Department of Energy’s Co-Optima program has explored biomass-derived blendstocks with fuel properties that boost the efficiency of engines, seeking to enable technology for fuel-engine co-optimization. Past analysis quantified benefits of introducing co-optimized fuels and engines for light-duty vehicles with the core assumption that efficiency gains would be the same for vehicles with and without hybridized power trains. Vehicles with hybridized powertrains, however, could experience a different energy efficiency change than conventional vehicles, which could be a decrease, if the blended fuel is not tailored for their operation, or an increase, if the hybrid engine’s operational conditions take better advantage of the blended fuel. Therefore, this study examines opportunities to reduce the environmental effects of light-duty transportation when fuel properties are tailored to the unique needs of hybrid electric and plug-in hybrid electric (HEV, PHEV) vehicles to improve their engine efficiency. The analysis tracks greenhouse gas emissions reductions on a well-to-wheels basis when co-designed fuels and engines for vehicles with hybridized power trains are introduced into the market. Engine efficiency gains and incremental vehicle cost are key parameters in the analysis as we seek fuel-engine technology that will significantly boost overall vehicle efficiency at a price point that is commercially viable. Twelve co-deployment scenarios were generated based on 3 different levels of engine efficiency improvement (8% ,10% and 12%) and 4 level incremental costs ($100, $250, $500 and $1000) and the corresponding environmental effects are tracked as the technologies gain market adoption. The preliminary results show that the effect of incremental cost and efficiency gain on vehicle sales indicates that adoption of co-optimized HEV, and PHEVs are relatively insensitive to incremental vehicle purchase costs up to $250. In addition, the results indicate higher adoption of co-optimized HEVs at $100 and $250 price increase and 12% efficiency gain while the adoption of HEVs and PHEVs across other scenarios remain consistent. From the best-case scenario ($100, vehicle price increase and 12% engine efficiency increase), the result shows that using biofuels with tailored properties and advanced engines to achieve an increase hybridized engine efficiency could translate to 17.5% reduction in greenhouse gas emissions from the light duty vehicle fleet including non-hybridized vehicles in 2050.

Keywords Biofuels, PHEV, HEV