Free Republic
Browse · Search
News/Activism
Topics · Post Article

To: Steely Tom
Which is why changing batteries (charged at the 'station' during off-peak hours) would be more efficient, if the engineering was done right. It would be a full service thing to do the swap, but with the right vehicle/battery engineering would be a five to ten minute job (about the same amount of time to pump a tank of gas, and get a big gulp).

I'm not arguing for the technology, but I can envision ways to make it more efficient at the nuts and bolts level.

122 posted on 02/12/2015 3:51:02 AM PST by Smokin' Joe (How often God must weep at humans' folly. Stand fast. God knows what He is doing.)
[ Post Reply | Private Reply | To 86 | View Replies ]


To: Smokin' Joe; NavVet; MHGinTN
I'm not arguing for the technology, but I can envision ways to make it more efficient at the nuts and bolts level.

Of course, and I'm the first to agree with you.

Others here are saying that Tesla technology is way more efficient in its use of energy, that the energy equivalent of only 3½ gallons of gasoline can propel a Tesla car 300 miles. I certainly hope that's true, although I have some doubts. If it's true, great.

The figures in my post #86 were derived from the assumption of 200 miles at 20 mpg = 10 gallons of gasoline. If the actual number of gallons to go more like 2 gallons, that's certainly good; the number of amps to charge in five minutes goes from 3400 down to something like 700. If we allow (as someone else said) 20 minutes for charging instead of five, that 700 amps drops to about 175 amps.

Even so, 175 amps at 220 volts is a lot of power, almost 40 kW. Multiply that by five or six charging stations, all of which might have to be running at the same time, and you've got large capital costs for the electrical utilities to run heavier cables to the gas stations and convenience stores. Still, 200 kW per 7-11 is not as bad as three or four megawatts per 7-11; the latter is not going to happen, in my view. 200 kW per filling station is probably do-able, although it undoubtedly require a building boom for power plants, and finding real estate for all those power plants is a problem in some parts of the country.

Another thing I haven't seen anyone mention on this thread is the issue of heating. Where I live (the northeast) it's been below freezing every day since Christmas. This is a serious problem if you're driving, especially with children. In fossil-fueled cars, you get lots of heat "free." The engine generates huge amounts of heat; you just tap five or ten percent of it and you can make the passengers very comfortable.

In an electric car, heating is a problem. If you generate it electrically, you impose a comparatively large load on the battery, causing a large drop-off in range. If you heat the cabin by means of fossil fuel, you're back filling up at the pump again, albeit less often, and only in the winter.

The same goes for air conditioning in the summer, which requires mechanical power. Where I live, air conditioning is a convenience issue, but in some parts of the country it's close to a survival issue during the summer months.

Still, I would imagine these problems can be worked out over time, or at least mitigated, as you suggest.

However, if fracking and other secondary and tertiary petroleum recovery methods keep the price of fossil fuels down, it will take the heavy hand of Government to force the economy to choose electric, unless there are some very big breakthroughs ahead of us.

Nanomaterials may bring us those breakthroughs, and I will be cheering if that happens.

To me, nothing would be sweeter for western society than to force that Arabs to have eat their oil.

123 posted on 02/12/2015 6:34:19 AM PST by Steely Tom (Vote GOP for A Slower Handbasket)
[ Post Reply | Private Reply | To 122 | View Replies ]

Free Republic
Browse · Search
News/Activism
Topics · Post Article


FreeRepublic, LLC, PO BOX 9771, FRESNO, CA 93794
FreeRepublic.com is powered by software copyright 2000-2008 John Robinson