In the rush for green automotive technologies, manufacturers and the media (although not it must be said the mainstream public) have been extolling the virtues of one manufacturers offering after another. This year more than a dozen new plug-in hybrid and pure electric vehicles will be brought out in spite of the fact it has taken over 10 years for such vehicles to reach 2.5% of new car sales in the US most of which are the Toyota Prius according to an article in The Economist. Even so, sales have been heavily skewed toward east and west coast markets like Los Angeles, the San Francisco Bay area and Washington DC in other words affluent ecologically focused neighborhoods that can afford the high costs and probably run a second car for when a hybrid falls short. The bulk of these new offerings will most likely be heading for the same markets so that in a few years the west coast could be home to several million vehicles whose owners will come home every evening and plug in their cars to the grid assuming of course they have upgraded their home to 220v supply and assuming their utility has upgraded the local transformers and distribution system. Homes will have to be upgraded to meet the demands of charging what amounts to a major electrical appliance being plugged into the house circuit. It takes 18 hours to re-charge the new Nissan Leaf on a 110v circuit according to the Economist, clearly a non starter if owners are hoping for cheap night-time power.
The effect of this on the local grid will be profound; the idea at the moment is that power will be drawn down between midnight and 6 am while generating capacity is currently idled but this is also when maintenance is carried out so systems will have to be re-designed to accommodate much higher loads for much longer periods. California already suffers localized brown-outs, suggesting the network is in dire need of improvement and new generating capacity. If the states are expecting utilities to meet the increased demand via renewables the cost will soar, the economics of wind and solar are questionable at best only attracting investment when there is subsidy, but if they are intended to meet power demand at night then an equally massive investment in storage will also be required.
For those owners who can’t get a full charge at night their only option may be to get as far as the office the next day and top up at work. Then the economics change fundamentally. During the daytime, peak power at an average of 33 cents/hour costs five times as much as it does at night, the equivalent of $3.63/gallon instead of $0.77/gallon if charged at night. Hopefully the take up of these new vehicles will be slow enough for utilities to make the necessary investments, but they are costs that all consumers are going to have to meet whether they drive an electric vehicle or not. It makes you wonder how manufacturers are going to roll out sales to beyond those who buy one for the environmental benefits.