Thursday, July 31, 2008

Why Are There No Cheap Electric Cars?

Written by Hank Green

I see this question in my inbox or in comments several times per week. The asker generally proposes one of several possibilities. These range oil-company assassinations to esoteric problems with the car's transmissions.

Fortunately for everyone, it's neither as exciting as assassination or as mundane as fundamental mechanical flaws. It's a collection of problems, actually, that are slowly being overcome.

And though we can't do it today, five years down the road, the future of electric cars will look a lot brighter.

So here's a collection of problems and their upcomming solutions:

Problem #1: Car manufacturers have put many billions of dollars and almost a hundred years into the development of the internal combustion engine, and they don't want to (or can't even imagine how to) abandon that investment for new technology.

Solution: It only took a global crisis, a quadrupling of gas prices and the majority of consumers shifting to efficient cars to convince them that maybe gasoline wasn't the best idea. Now even the biggest, oldest and stodgiest of the car manufacturers are investigating electric cars.

Problem #2: Batteries do not store power as efficiently as fossil fuels. They are heavy, bulky and provide far less power per unit of weight than gasoline, ethanol or hydrogen.

Solution: The EV1 overcame this by being a truly tiny car, and having a fairly low top speed. But still it could only travel less than 100 miles on a charge. Now cars are being updated with Lithium Ion batteries which can carry far more power per pound (though still not as much as gasoline.)

And range-extended EVs like the Chevy Volt allow the battery to remain small, while the on-board ICE can recharge the batteries when they get low. And, even more fascinating, an ultra-stealth company called EEStor says they have a new ultracapacitor technology that could store far more energy than batteries, and charge in just a few minutes

Problem #3: Filling a gas tank takes five minutes, charging a battery can take as long as 12 hours.

Solution: I'll start with EEStor again, who says that their ultracapacitors can charge in minutes but still power a car for over 300 miles. Pheonix Motorcars has a nanotech based Li-ion battery that can also be charged in a matter of minutes. Unfortunately, both of these technologies require extremely high voltage, so the cars could not be charged quickly at home.

Extra infrastructure in the form of charging stations would be necessary to allow these batteries to charge quickly.

Other solutions to the long-charge-time include Project Better Place's plan to have battery swapping stations (instead of gas stations.) The idea being that PBP owns the batteries, and chargest them at stations. A car-wash-like facility swaps out a freshly charged battery for your used one. This, as well requires a ton of new infrastructure though.

The Chevy Volt, finally, takes a middle road, and basically lets you charge the battery with gasoline when you really need it. So you can charge at home with electricity over long periods, but if you need a boost NOW the gasoline option is always available.


Without overcoming those obstacles, there would indeed never be a cheap, convenient, mass-market electric car. But the good news is, we're on the verge of overcoming (or, in some cases, have already overcome) the limitations of previous eelectric cars.

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