No one will want to wait for a couple hours to plug their cars in... so just make smart chargers. It could default to an overnight mode which would charge the car at some time during the night (an algorithm using a random number generator would ensure that all the cars would have a good charging distribution throughout the night). A selectable instant mode would immediately charge the car if the person needed to go out again soon.

Another solution would be to charge a significantly higher rate for those peak hours, while discounting non-peak hours. The difference would have to be pretty substantial to make an impact though.

...We've had troops in Japan and Germany for over 60 years. Does that mean we LOST WWII ?!?!?...

Q: Won't plugging in cars lead to building more coal and nuclear power plants?
A: Although Plug In America favors more use of electricity for transportation, we won't need additional generating capacity for this for decades to come. During that time we can shift to cleaner, renewable power options that cause less environmental harm than fossil fuels and nuclear plants.

The existing electrical grid's off-peak capacity for power generation is sufficient to power 84% of commutes to and from work by cars, light trucks and SUVs without building a single new power plant if people drive plug-in hybrids, according to the U.S. Department of Energy. In addition, the existing nighttime electricity can be stored in plug-in vehicles and retrieved during peak-demand hours through vehicle-to-grid technology for use by the grid, helping to meet society's daytime power needs.

New power generation facilities should focus on clean, renewable sources such as wind, solar, biomass, and geothermal power. Combine these with the institution of energy efficiency measures throughout society, and we can meet the targets needed to avoid the worst effects of global warming without resorting to more coal or nuclear plants, according to the 2007 report Tackling Climate Change ( www.ases.org).

courtesy www.pluginamerica.org

I agree with everything zippo42 said. However, for the information of those who need to know, there are a few key facts and assumptions that need to be made. For instance:
1) Many readers may not notice the difference between the article assuming that people plug in all at once, as soon as they get home, compared to your reference to "off-peak capacity". Everyone should be aware that this term is essentially referring to the the maximum the entire system can generate and carry, compared to how much is used in the middle of the night. Which explains how both situations (yours and the author' s) can be accurate at the same time.
2) That, even though the grid cannot currently handle everyone plugging in their vehicles at once right now, there are power companies working on technology such as the Smart City project mentioned here at http://www.xcelenergy.com/XLWEB/CDA/0%2c3080%2c1-1-1_15531_43141_46932-39884-0_0_0-0%2c00.html , that will eventually make that possible, without the requirement of building new power plants.
3) That battery efficiency, increased sufficiently above current levels, is necessary in order to make PHEV vehicles even cheap enough that we can all afford them. Not to mention the fact that current battery technology would not allow a capable system to retreive much, if any electricity during peak-demand hours through vehicle-to-grid technology, and still get people home at night.

This problem already exists for Air Conditioning, and a good proportion of Power Capacity exists only for the Summer. It looks like we'll have to scale price according to availability, in order to get people using Heat Pump Technology year round, and to get them using power saving devices for Vehicle Recharge.

In fact, while Electric Motors give better Acceleration, Oil Burning Engines have greater range, and someone's already doing a Turbo-Electric Hybrid in a long range muscle car. Adding a portable generator to your LiPo Power Pack, won't just give you a longer range, but if we proportion electric pricing according to the spot market, many would use this feature to run their domestic Air Conditioning. It's not a big jump, from having a turbine recharger, to carrying an emergency generator, for those hot summer nights; A house of four people would need only three horsepower. Some could even be returned to the Grid.

Arawn

This is an rather unnecessarily alarmist attitude. EVs are essentially an answer to rising oil prices, rising pollution, rising transportation costs and unhealthy levels of vehicular emissions.

Firstly, people are not all going to go out and buy an electric vehicle right this moment, the demand and the supply of these vehicles will rise gradually and any consequent rise in demand for electricity will only be required to keep pace with that.

Secondly, if demand for electricity does in fact rise considerably in the foreseeable future, a time table and cost structure could be put into place by supplying grids that could easily take care of such an eventuality.

If, for acquiring the obvious benefits available thru EVs we have to make some adjustments and modifications, we must make them!

Electric cars like the Aptera and Teslar should have a spare battery that plugs in and charges while you're using the other one. As suggested, they could have timers to charge up at optimal times for the area grid. Eventually solar arrays should be able to charge these cars. Having a hybrid with a either a carbon fuel or alt-fuel backup would extend driving range (they have cars that run on alt-fuel in brazil). No one wants to be stuck waiting hours for a charge. Back up batteries, Back up fuel source, Problem solved. Honda originally talked about using converting CRX bodies into e-cars so no one needs to convert to an ugly 3-wheel green truck (is that thing an oil company plot to discourage electric cars?). The original chevy-volt specs got 240/mph now it's going backwards. Beware of oil company games like putting out substandard electric cars to kill demand. Woulnd't put ANYTHING past them. checkout: http://www.ev1.org