It depends on when people are going to recharge their cars, basically. A new study from the Oak Ridge National Laboratory (ORNL) says that a move to plug-ins could require either a bunch of new power generation resources or maybe none at all – everything depends on when most people are going to recharge their cars.
While some assessments that there will be no impact make assumptions that owners will charge their cars only at night, Stan Hadley, of ORNL’s Cooling, Heating and Power Technologies Program feels this is unrealistic. “That assumption doesn’t necessarily take into account human nature,” said Hadley, who led the study. “Consumers’ inclination will be to plug in when convenient, rather than when utilities would prefer. Utilities will need to create incentives to encourage people to wait. There are also technologies such as ‘smart’ chargers that know the price of power, the demands on the system and the time when the car will be needed next to optimize charging for both the owner and the utility that can help too.”
ORNL ran several scenarios in their study, using a assumed market penetration of 25% for plug-in hybrids by 2020. The worst case scenario assumed that all plug-in owners would charge their cars at 5 PM – with this scenario up to 160 new large power plants would be needed to supply the extra electricity. The best case scenario assumed that everyone charged their cars after 10 PM – that’s when the load on the electrical system is at its low and the wholesale price for electricity is at its cheapest. In this scenario, no additional power generation would be needed. While neither scenario is realistic, the ORNL study concludes that with incentives and tools such as smart charges, the need for additional power capability can be minimized.
You can check out the full report at the ORNL Review – download the pdf for the issue and you can find it on page 14 – the article is entitled “GIVING BACK
Plug-in hybrid electric vehicles may have an unexpected value”