Stored energy from electric vehicles could be used to power large buildings and, contrary to popular belief, could even help extend the lifespan of batteries.
There have been concerns that using lithium-ion EV batteries to transfer energy to grids could lessen battery life and lead to degradation, however researchers from Warwick Manufacturing Group, part of the UK’s University of Warwick, have found a way to take energy from idle EVs without damaging the batteries, and could actually increase battery life by about 10 per cent over a year.
Dr Kotub Uddin, along with colleagues from WMG’s Energy and Electrical Systems group and Jaguar Land Rover, have for the past two years been researching advanced lithium-ion batteries used in commercially available EVs, and created an advanced battery degradation model to predict battery capacity and power fade under a variety of ageing acceleration factors.
Now they’ve combined this model with a “smart grid” algorithm to calculate how much energy a vehicle would need to carry out daily journeys, as well as how much energy could be taken without negatively affecting battery life.
Using WMG’s International Digital Laboratory as a case study – a building that houses about 360 staff and contains a 100-seat auditorium, two electrical laboratories, teaching laboratories and meeting rooms – the researchers calculated whether enough energy could be taken from EVs parked on campus to power the building.
Using an estimate that 2.1 per cent of cars on campus were EVs (the UK market share), the researchers concluded enough energy would be spared to power the buildings, and that capacity fade in participant EV batteries would be reduced by up to 9.1 per cent, and power fade by up to 12.1 per cent over a year.
Dr Uddin said the findings reinforced the attractiveness of vehicle-to-grid (V2G) technology, with EVs able to help buildings meet peak demand and provide income for vehicle owners.
“Not only is vehicle-to-grid an effective solution for grid support – and subsequently a tidy revenue stream – but we have shown that there is a real possibility of extending the lifetime of traction batteries in tandem,” he said.
This could provide a strong incentive for business to pursue EV fleets.
“The results are also appealing to policy makers interested in grid decarbonisation,” Dr Uddin said.
The research, On the possibility of extending the lifetime of lithium-ion batteries through optimal V2G facilitated by an integrated vehicle and smart-grid system, is published in Energy.
Call for Australia to increase EV share
The news came as the newly established Electric Vehicle Council and ClimateWorks released a report into the state of electric vehicles in Australia, finding that the country was falling behind on uptake compared to the rest of the world.
While there was a 40 per cent global increase in EV sales in 2016, in Australia sales fell by 23 per cent.
The report said policy support for EVs in Australia was in its early stages and the government needed to step up support.
“In Australia, the adoption of light vehicle CO2 emissions standards could provide an overarching incentive to support electric vehicle uptake, provide a signal to industry to support greater investment, and could help to lower electric vehicle costs over time,” the report said.
Electric Vehicle Council chief executive Behyad Jafari said Australia was one of the few remaining developed countries without light vehicle CO2 standards in place.
“Electric vehicles, powered by renewable energy, emit zero carbon emissions, while providing a boost to the economy, providing opportunities for investment in Australian industry,” he said.