Even if almost all of them were replaced by plug-in electric vehicles, which wouldn’t happen for at least 50 years under the most optimistic forecast, the existing power grid could easily handle them even in winter, when demand is heaviest, the study says.
"In the summer, when there is much more spare capacity, the grid could theoretically support over 8.8 million vehicles," says the study by four researchers from the University of Victoria’s Institute for Integrate Energy Systems.
The challenge won’t be finding enough juice to recharge them, but when to do it and how to deal with changes in BC Hydro’s revenues and government fuel taxes.
The study by the Pacific Institute for Climate Solutions says British Columbia’s light-duty fleet – private cars, vans and pickup trucks – totals about 2.54 million vehicles.
Even if almost all of them were replaced by plug-in electric vehicles – which wouldn’t happen for at least 50 years under the most optimistic forecast – the study claims the existing power grid could easily handle them even in winter when demand is heaviest.
"In the summer, when there is much more spare capacity, the grid could theoretically support over 8.8 million vehicles," says the study by four researchers at the University of Victoria’s Institute for Integrate Energy Systems.
The grid, which gets 90 per cent of its power from hydro dams and other renewable sources, can easily recharge vehicles from B.C. commuters, whose median daily round trip is just 13 kilometres – less than 10 kilometres for 40 per cent of them.
Most would be recharged overnight when demand for electricity drops off drastically. But managing a growing volume of plug-in electric vehicles isn’t a simple equation, the study points out.
BC Hydro, via its Powerex subsidiary, profitably exports stored low-cost hydro power to U.S. and neighbouring provincial utilities at peak daytime periods while importing cheaper Alberta power overnight.
That profit margin might shrink if thousands of electric cars start using power overnight, leaving less in reserve for peak-demand exports.
Study co-author Curran Crawford said Hydro operations staff connected with electric-vehicle development reviewed the study but researchers didn’t talk to the marketers at Powerex.
Plug-in electric cars are still a relatively small share of the overall power market, he said. "I think it is something that’s on their radar," Crawford said in an interview. "It feeds more into their future plans for requiring generation and how that works."
Crawford pointed out much of the off-peak imported power comes from Alberta’s coal-fired generators, purchases that will likely be phased out under a B.C. government policy of requiring green-energy self-sufficiency by 2016.
"So there would probably be constraints from that perspective as well," he said. Technology will help address some of these issues, the study says.
So-called smart meters will determine the best time to recharge based on the lowest cost of power to the consumer and load on the grid.
Units are also being developed to allow the utilities to regulate charging, which opens the door to two-way power transmission – so-called vehicle-to-grid applications.
That means the vehicle owner can sell power stored in the car’s battery back to the system when it’s needed and the network of plugged-in vehicles acts as a buffer for the entire system.
"Regulatory-wise, you’d need pricing structures that actually reward that behaviour," said Crawford.
"We have more-or-less fixed-rate pricing right now but we’re going to a variable rate in the future and lots of other jurisdictions are at time-of-use pricing."
Vehicle-to-grid activity likely wouldn’t leave a driver heading out for the daily commute at risk of not having enough of a charge, he added. Utilities would draw on the batteries briefly to balance voltages and frequencies.
"You might be feeding power in and out of the vehicle on the order of seconds," he said. "It’s not like you’re constantly drawing down the battery when you’re doing that."
Although the study focuses on British Columbia, Crawford said it is also relevant to other provinces that get a large percentage of power from dams, such as Manitoba and Quebec. "If you’re highly hydro dominated, then you’re in a really good place to be able to do this," he said.