Limiting electric vehicle charging to off-peak times could cut the cost of a full recharge in half, according to a study by Pittsburgh’s Carnegie Mellon University.
Due to be published in the February edition of the Applied Energy journal, the study was funded by CMU’s RenewElec project and the National Science foundation, and looked at the effects of electric vehicle charging on power plants in New York.
It noted that while there aren’t many electric vehicles in the region, federal and state subsidies are promoting uptake among drivers which will put extra demand on the grid at peak times as numbers grow. Particularly if most drivers plug in after work, when electricity generation is at its most expensive due to the high demand.
By varying their charging rate depending on the electricity source, the study said drivers could take advantage of limiting charging speeds when the cost of generating the power is at its highest. It could also allow the grid to compensate for fluctuations caused by renewable sources, in turn helping to avoid increases in energy bills as utility companies have to use expensive power sources more often.
Co-author Jeremy Michalek, an associate professor of mechanical engineering and Engineering and Public Policy, and director of the Vehicle Electrification Group, said: ‘It is already cheaper to charge an electric vehicle than fill up a gasoline vehicle, but allowing grid operators to control electric vehicle charging speed could reduce these costs further.
‘We see additional savings up to $70 (£42) per vehicle each year or even higher for systems that expect new power plant construction and systems with a lot of wind power.’
Ongoing studies will now assess the environmental and health impact of the cheapest power sources, which typically use fossil fuels, and how increased electric vehicle use could alter air quality in the region.