A near-term solution that addresses many of challenges consumers, researchers, automakers, utilities and government agencies have had historically with conventional and electric vehicles, is the plug-in hybrid vehicle (PHEV)(Bradley, et. al., 2009). The PHEV is a type of hybrid vehicle that uses a portion of its propulsive energy from electricity generated from the power grid. The current PHEV prototypes have successfully demonstrated increased transportation energy efficiency, reduced carbon emissions, reduced criteria emissions, reduced fueling cost, and improved transportation energy sector sustainability. With these beneficial impacts of the PHEV, the transportation sector will be able to displace petroleum as a transportation fuel and access the lower-cost and cleaner energy available via the power grid.—Blake Kos
Bradley, T., Frank, A., 2009. Design, demonstrations and sustainability impact assessments for plug-in hybrid electric vehicles. Renewable and Sustainable Energy Reviews Volume 13, Issue 1, 115-128.
Bradley and Frank analyze the potential of plug-in hybrids in replacing petroleum-based transportation fuels for the transportation sector. They claim that PHEVs confront the issues associated with both the internal combustion and electric vehicles and believe that PHEVs are the near-term solution to displacing petroleum as transportation fuel.
PHEVs are similar to conventional hybrid electric vehicles in that they both incorporate an electric and internal combustion drivetrain, however, the main difference is that an PHEV has an additional component called the charger. The charger permits the PHEV to draw and store energy via the electrical grid onto its on-board batteries. Because the PHEV utilizes both an electric and internal combustion drivetrain, the PHEV must be designed and controlled by the vehicle’s architecture and energy management system. The energy management system regulates the electric and combustion drivetrain systems to provide the most desirable mixture of power and efficiency thus allowing the vehicle to be driven with better performance, higher energy efficiency, lower environmental impact and lower cost than conventional HEVs (hybrid electric vehicle).
Based on data gathered from PHEV prototypes, PHEVs offer dramatic reductions in petroleum consumption, criteria emissions (vehicle evaporation emissions, refueling emissions, electricity generation emissions and the emissions associated with fuel extraction, processing, production, transportation and distribution.) and carbon emissions. For example, PHEV with a 100 km driving range in electric vehicle mode driven and charged nightly, will result in an 84% decrease in gasoline consumption, compared to a conventional gasoline-powered vehicle. Since PHEV have less frequent refueling events, the criteria emissions associated with PHEV are reduced. However, this can be offset depending on means of electricity generation. If PHEVs are plugged in during off peak hours, grid efficiency will be improved and electricity costs to consumer will be lowered. As of now, the amount of PHEVs in the market is insignificant however, as consumer interest rises and better technology is incorporated into PHEVs, petroleum-based transportation fuels will be displaced.—Blake Kos