What utilities should know about electric cars

1. How many electric vehicles will be on the roads, in what time frame? The electric car market has barely started, and key technology, including next-gen batteries, that can deliver the wide adoption of electric vehicles have yet to be developed. EPRI came up with three forecasts for the cumulative number of electric cars that will show up between 2010 and 2030. The low estimates are 3.1 million by 2020 and 15 million by 2030, based on historical sales from 2000 to 2008. The medium estimates are 5.8 million by 2020 and 35 million by 2030, based on historical sales and carmakers’ announcements of new models and production volumes. The high side will be 12 million by 2020 and over 65 million by 2030. And, yes, that’s a large range for an estimate.

2. Electric vehicles’ share of the car market. The low estimates put electric cars at 1 percent of the total cars driven in the U.S. by 2010 and 4 percent by 2030. The medium estimates peg the market penetration at 1.9 percent in 2020 and 9.4 percent in 2030. In the most optimistic scenario, electric cars will make up 3.9 percent in 2020 and roughly 17.7 percent in 2030.

3. How cheap is the fuel for electric cars? Electric cars can be fueled up at one-third or a quarter of the cost of a gasoline car, given the current pricing of both fuel types. Utilities are worried that because electricity is cheaper to start with, drivers might juice up their cars even in peak hours, when electric rates are high (but not as high as comparable gasoline costs). But providing and educating drivers about the low rates they could get in off-peak hours will help to minimize the need to increase electricity supply during peak hours and alleviate any stress to the grid.

4. Charging at home is ideal. Although residential charging equipment will typically require 1.4 kW to 7.7 kW of power, peak electricity demand from electric cars will be far lower, at 700 watts. That’s because there is enough time from early evening to the next morning to accommodate charging. By providing incentives, such as low electric rates, utilities can nudge car owners to start charging after 9 p.m., when overall demand for electricity is much lower than earlier in the evening. The hours between 11 p.m. and 3 a.m. are most ideal and cause the least impact to the grid. But the report cautions that if most people program their cars to start charging, say, right after 9 p.m., then the utilities will have to deal with a big spike in demand.