Vattenfall is working with Volvo in hopes of addressing concerns about how the widespread adoption of plug-in hybrids and all-electric vehicles will affect the electrical grid. The worst-case scenario is that everyone who owns one of these cars will come home from work at 5 P.M. and plug in, leading to stresses on the grid and possible brownouts. “Will people plug in at every opportunity or not? We don’t think that’s going to be the case, but we only have computer models,” says Sugioka.
The Swedish collaborators will also monitor whether most people charge the cars in garages or will take advantage of fast-charging stations located in public places, which could offer electricity solely from renewable sources of power, such as wind. Sugioka says that Vattenfall has not yet announced which companies are providing the charging stations or how many there will be. Drivers could use them for a fast charge to avoid having to employ the diesel engine–but there is a trade-off. “Fast charging heats up the batteries and shortens their lifetime,” says Sugioka. Fast charging may also strain the electrical grid if people use it during peak hours, instead of charging the cars at home at night.
The Swedish project is one of a number of studies under way to monitor how people will use plug-ins. A group of anthropologists led by Tom Turrentine, director of the Plug-in Hybrid Electric Vehicle Research Center, at the University of California, Davis, has distributed plug-in vehicles equipped with monitors to several families. “We suspect that people will make some adjustments to save energy and oil, but it’s hard to say how much people will change: we’re creatures of habit,” says Keith Hardy, acting director of the FreedomCAR and Fuel partnership at the U.S. Department of Energy.