Council increases its forecast of electric vehicle power demand

The Council is revising upward its estimate of how much power plug-in electric vehicles will use in the future, in light of anticipated consumer response to high gasoline prices and technological advances that allow plug-in electric vehicles to travel increasingly farther before recharging.

In its now three-year-old Northwest Power Plan, which is implemented by the federal Bonneville Power Administration, the Council estimates plug-in electric vehicles will account for between 100 and 550 average megawatts of electricity per year by 2030, equal to the annual demand of about 60,600 to 333,300 Northwest homes. A recent analysis by the Council’s Power Planning Division revises the demand forecast to 130-580 average megawatts per year by 2030, an increase of 30 percent on the low end and 5.4 percent on the high end.

"Electric vehicles are slowly but steadily increasing their share of the new-car market," Council Chair Joan Dukes said. "As the regional power-planning authority, we are working to better understand the implications of this small but growing source of electricity demand."

The Council continues to believe the advent of plug-in vehicles will not require new power plants to be built, despite the increased power demand they will cause. That is because 1) a number of new federal standards for electric appliances and equipment will reduce demand nationwide as the standards are implemented over the next several years, and 2) experience shows recharging mainly occurs overnight when power demand is low.

The Council revises its 20-year power plan every five years and is beginning to explore issues that will be addressed in the next revision in 2013. The impact of plug-in vehicles on the regional electricity supply is one of those issues.

The revised forecast of future electric-vehicle power demand reflects three years’ of new information about plug-in vehicles including 1) decreased battery efficiency during cold winter weather; 2) increased annual power demand over time to reflect interstate travel as vehicle travel distances increase; 3) increased consumer interest in electric cars when gasoline prices are high, and decreased interest when prices are low; 4) better understanding of why people buy these cars and how long they might keep them; and 5) energy use per vehicle.

The Council’s 2009 Power Plan assumed that by 2011 there would be 2,000-8,000 new plug-in electric vehicles in the Northwest. In fact, the actual number was about 2,000. New vehicle sales languished for the last few years, and the length of new-car ownership has increased to a record 71 months. This trend contributed to electric vehicle sales that were lower than the Council anticipated. Fuel efficiency of all new vehicles also has improved steadily, from 20 miles per gallon in 2007 to 23 in 2011, and vehicle emissions have declined over that time, by about 14 percent -- improving the appeal of gas-powered vehicles to energy-conscious consumers, perhaps deterring some people from buying electric vehicles.

Despite a huge jump in plug-in vehicle sales from 2010 (345 sold nationwide) to 2011 (17,813 sold), plug-ins still account for a tiny fraction of all new passenger vehicle sales – 0.03 percent in 2011. By January of this year, 314 Chevrolet Volts and 1,572 Nissan Leafs were registered in the Northwest, accounting for about 17 percent of the Leafs and 3 percent of the Volts in the country. But the recent trend is changing rapidly. Sales increased dramatically this year compared to last, perhaps in response to gasoline prices. In the first three months of 2012, Volt sales were up 224 percent and Leaf sales 283 percent nationwide compared to 2011. The Council assumes plug-in vehicles will represent 10-40 percent of the new-vehicle market in the Northwest by 2030.