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Comment by wmeredith | Hacker News Reader

How many tons of coal did they burn?

Assuming 2460 kwh/ton of coal, and 36kwh per 100 miles of driving this driver burned 1.7561 tons of coal.

Assuming he drove a gas powered Honda civic instead he would have burned 375 gallons of gasoline (12000 / 32 combined MPG).

One ton of coal releases 2.86 tons of C02. One gallon of gasoline releases 19.64 pounds of C02.

Driving the electric vechile released 5.022 tons of C02.

Driving the gas civic would have released 3.68 tons of C02.

All numbers shamelessly cribbed from whatever google result seemed nice.

However the driver lives in New Jersey, where only 10% of the power comes from coal (as of 2005). There, I find that it is only 0.713 lbs of CO2 per kwh, so he'd only be releasing about 1.5 tons of CO2.

CO2 data from here: http://www.miloslick.com/EnergyLogger_files/State_Electricit...

Tesla has a cute map of electricity generation by state: http://www.teslamotors.com/goelectric#electricity

It looks like there isn't any state where driving an electric actually produces more CO2 than driving a gas car. And that's before you include the CO2 generated from refining oil (which requires a fair amount of electricity).

That's a great map except they fail to state the MPG of the "Gas Car" they are comparing too. Given the numbers in that, I'd be willing to bet a Prius outperforms the Electric in some of the worst states.

Edit: Assumption is stated as 22mpg at the bottom of the page.

That's fair if you are comparing the Model S to a similar luxury car. It also means the Prius wins in a lot of states.

> It also means the Prius wins in a lot of states.

That's true. But I think Tesla is trying to sell the Model S to people who would otherwise buy a similar luxury car. There are a not-insignificant number of people in the world who just hate the Prius because it sacrifices handling, performance, and interior finish for the sake of fuel-efficiency. If Tesla builds and sells a car that those people like, isn't it still a net win? People who like hybrid Priuses can still buy them.

Yup. Electric cars are one half of the puzzle. Moving away from coal and towards other sources are the other half.

It's good that one half of the puzzle is mostly complete, as the electric car seems to be here for good. I think moving energy sources away from coal will be the more difficult and time consuming task.

> All numbers shamelessly cribbed from whatever google result supported my thesis.

FTFY

What thesis would that be? Feel free to go do your own calculation and contribute anything at all.

Snark like this is annoying and doesn't contribute in any way to the conversation. If you don't agree with someone's numbers, then take a few minutes and critique their data or do a little of your own research and post your findings. It's a lot more interesting and a more successful way to get your point across.

On the other hand, one could in theory outfit the coal plant with equipment to capture much of that carbon and prevent it from being released into the atmosphere.

That's much harder to do for the car, because you only have a limited budget for space and weight to attach things to the car.

Well, if you care about the green house impact of his use of his car, it's pretty good.

Driving a regular car 12k miles will net you about 4.6 tons of CO2.

His 36 gallons of gas, plus his electricity consumption if we assume that he uses about 36 kwh/100 miles and that he lives in New Jersey (as per http://media.gm.com/media/intl/en/chevrolet/news.detail.html...), which does not just burn coal for electricity production, we can expect him to have emanated ~1/3 ton of CO2 with his Chevy Volt over that period.

So a good 15 times better.

I've recently switched to having all of my energy come from renewable resources, it isn't all that difficult to do at this point.

How do you define renewable?

Shh, we have to ignore all environmental externalities other than CO2 emissions caused by burning petroleum products. Otherwise we would have to face the fact that our lifestyles are directly at odds with the health of the planet we live on.

Industrial civilization is engaged in a war against entropy which it is destined to lose.

Life is engaged in a war against entropy which it is destined to lose.

Sure, but my statement sort of has an implied time scale (e.g. a human time scale), and your implied time scale is cosmological. Maintaining the rational economic system that we live under requires immense energy inputs, and while it obviously can't be sustained for the next trillion years, it also can't be sustained for the next hundred.

While I wouldn't exactly phrase it like that, it is an important question to ask: Where did he do most of his charging and how does the electric utility in that area produce their electricity?

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