Ricardo Company, Jaguar-Land Rover and Amberjac Projects have worked with England’s Technology Strategy Board to create the Range Extended Hybrid Electric Vehicle (REHEV) project. REHEV recently published a report that sets out to eliminate concerns about grid overload with the eventual mobilization of electric vehicles (EVs). The report was assembled from computer simulation data produced by the group’s members based on existing energy use, traffic patterns and other criteria in the United Kingdom.
In order to eliminate doubters of the ability of utility grids to deal with EVs, REHEV members used four testing categories with its simulated prototypes. The worst scenario in the report was uncontrolled domestic charging, a free-for-all where commuters and public agencies charged without moderation. REHEV also dealt with uncontrolled after-hours or off-peak charging and “smart” charging using household outlets. The final category was uncontrolled public charging at stations in city lots and parking structures during work hours.
REHEV found that the worst scenario for the public grid would have little impact on overall energy consumption. The overall electric demand in the United Kingdom would increase only 2% if there was 10% market penetration by PHEVs and EVs or about three million vehicles. The off-peak charging scenario would mean less than 2% increase in electrical demand during the night and no increase in demand during the day. REHEV members concluded that the 10% market penetration figure is unlikely and the region’s electrical systems could handle hundreds of new EVs.
The results of the EV and PHEV simulations have encouraged REHEV’s efforts to produce a hybrid electric-diesel drive train. REHEV members plan on testing this drive train in multiple vehicles including a sports utility vehicle and a passenger van. The goal of the REHEV collaboration is a drive train that can travel up to 20 miles on all-electric power, which can cover errands and neighborhood commutes.
REHEV’s simulations are heartening for EV supporters but lack the substantiation needed to push further development of vehicles and infrastructure. While a simulation of existing utility demands may seem satisfactory, critics of mass EV implementation will ask for harder evidence before relenting. The next step for REHEV is to complete the proposed drive train and get test vehicles on UK streets to produce that evidence.
