An Engineering View of the push for Electric Cars
 Many people think that electric cars will help the environment and get us away from fossil fuels. Let's look at it closer:
Electric vehicles are not, "zero emissions" vehicles. They are "displaced emissions" vehicles. For very polluted cities, this can make a lot of sense. It takes a certain amount of energy to take us, our cargo, and our 3000-7500 lb vehicles from here to there, and this has to come from somewhere. On average, 70% of the electricity from your home's outlets is produced by burning some petrochemical or coal (i.e. non-renewable fossil fuel). Since you have to burn the energy-equivalent (BTUs or kWhrs) of fossil fuel at the powerplant, plus ~7% for transmission losses, relative to what you pull from the wall outlet, this works out to a lot of fuel that's consumed. The CO2 & pollution emissions from producing this electrical energy occur at the power plant and not at your car. So, no free lunch, yet again. Also, if you burn lots of coal, like the U.S. and China, you get lots more CO2 from this than you would if you burn a petroleum based liquid or natural gas.
Lets look at a real car in production: The 2-seat Tesla roadster electric car with it's 220 mile range, takes 70 amps for a 3-4 hour recharge at 220 volts (3-phase, that's 21,778 watts), or 15 amps for a 40 hour recharge at 120 volts (that's 1800 watts). If you want to use this car as a commuter, you'd have to pull ~30 amps at 220 volts (3-phase, that's 9,334 watts) to recharge overnight (8 hours). This is a full recharge, so topping off the battery takes less time (or less amps).
Also, note that typical modern home electrical service is 100-200 amps, and it is common for older homes to have 60 amp service, so adding a 70 amp load requires a thorough review (& possible rewiring) of the home's electrical system.
A typical US home uses ~750 kWhrs electricity per month, which works out to an average of 1027 watts used 24 hours/day. So, plugging this car in would increase a typical home's electricity consumption by 2,120% for a quick charge and 175% for the longer recharge. For an 8 hour recharge that works out to 909% household power increase during charging. Any way look at it, recharging an electric vehicle takes 2 to 21 times the average power used by a household - these types of vehicles place a huge load on the electrical grid. Therefore, until we can install more power lines and electrical generation capacity (& spend trillions of dollars doing so), we could get brown-outs as millions of people return from work and plug in their electric or plug-in hybrid vehicles for recharging.
Once again, there is no such thing as a free lunch.
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