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RE: One True Test
By Hoser McMoose on 5/4/2008 4:01:34 AM , Rating: 2
You'll need to produce far more electricity

With a bit of intelligent charging this actually isn't that big of a problem. You need to build your electrical power generating capacity for peak demand. During off-peak times a lot of capacity is usually sitting unused.

The simple solution here is time of day pricing for electricity. Smart people will recognize that it costs them, for example, $3 to fill up their car by plugging it in at night vs. $10 to fill it during the day.

A more complex solution involves some smarts on the charging station to adjust according to demand, possibly even allowing electricity to flow back out of the car and onto the grid at peak times.

but I'm guessing that burning billions of tons of coal won't bode well for the Earth's atmosphere


You'll need to transfer far more electricity over the grid.

Exact same story here as with the generating capacity but it's actually even easier as far as the lines go. Unless there is a near immediate switch to 100% electric vehicles this one is a non-issue (at least above and beyond the fact that the grid needs to be well maintained, electric cars or no).

Battery technology is still trailing behind your car's fuel tank:

HERE is the real key holding electric vehicles back, batteries. They're expensive, they're heavy, they're not as reliable as they should be (particular things like cold weather reliability), ohh, and did I mention that they're REALLY expensive? Like $40,000 in the case of the Tesla Roadster's 56kWh worth of batteries or $10,000 for the Chevy Volt's 16kWh worth.

The latest and greatest Li-Ion batteries available today are only JUST BARELY meeting the minimum requirements to make electric cars viable. Older technologies like the lead acid batteries or NiMH batteries found in the EV1 were not at all up to the task. Those two technologies also have serious environmental impacts, something that is greatly reduced in the case of Li-Ion batteries.

Still I think it will take at least one more major advancement in battery technology to make electric vehicles truly viable. The good news is that a lot of really smart people are working on this next technological leap. One technology that seems VERY optimistic is EEStor's capacitors:

I'm cautiously optimistic about the technology involved, though I'm holding final judgment until I see something a bit more concrete then some press releases.

For now though batteries are definitely a limiting factor. They are the reason why I see a LOT more potential in series hybrid designs, such as the Chevy Volt, as compared to a pure battery electric vehicle.

Electric cars are (far?) heavier then their fuel driven counterparts

This is due entirely to the battery issue mentioned above. The rest of the components are actually lighter in electric vehicles. Electric motors are much smaller and lighter and they can operate either without any transmission or, at most, with a very simple transmission. These components are very heavy on a conventional vehicle.

As an example, the Chevy Volt has an estimated curb weight of about 3100lbs, slightly less then the similarly sized Chevy Cobalt. And that is for a series hybrid with batteries, electric motors and a small ICE.

Fuel cell based cars maybe the future

Hydrogen fuel cells are a load of crap. They're just another battery technology, but a very heavy, expensive and inefficient one. Right now we're looking at a similar energy density to Li-Ion but charge efficiencies worse than old lead acid stuff costs that are astronomical. Even if we had the infrastructure in place to refill them hydrogen fuel cells would be a very poor choice.

RE: One True Test

then we have gearboxes etc and total effeciency is 30%.




RE: One True Test
By masher2 on 5/5/2008 11:17:08 AM , Rating: 2




