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Chevy Volt: Is This Our Future?

nytimes.com

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Re: Chevy Volt: Is This Our Future?

#41

Post by ChuckMcM »

bbg wrote: post #19

I want to love electric cars, but I see two big issues: (1) if they go mass market, all that electricity will still have to be generated somewhere. Coal? Nuclear? (2) The batteries need rare-earth minerals, which are brought to market through environmentally-degrading open pit mining. Furthermore, at this point, most rare-earths are available almost exclusively from China.

An internal combustion motor is, at best, about 20% efficient [1], whereas if you burn the same fossil fuel in an electric power plant using a combined cycle configuration you can reach 60% [2].

Now the electric company loses some of that by sending over wires to your house (or where ever the charger is) but its still a big win. What that means in mathematical terms is that if you took the same fossil fuel we burn today in cars and instead made electricity out of it and ran our cars on the generated electricity, we could either have nearly 3x the cars for the same fuel, or the same number of cars using 1/3 the fuel.

The win here is that if you have room to build a big heavy specialized machine to convert fossil fuel to electricity you can invest in all the things that make that really efficient. Whereas if you have to put an engine in every car, there is a financial and weight limit to how complex you can go (not that some of the extreme low sulfur diesels aren't wicked complex, they are).

Also you don't need rare earths. You only need them for permanent magnet motors. A fully electric car can by built with practically none, they are available locally if you need them[3].

[1] "Most steel engines have a thermodynamic limit of 37%. Even when aided with turbochargers and stock efficiency aids, most engines retain an average efficiency of about 18%-20%.[11][12] " - http://en.wikipedia.org/wiki/Internal_combustion_engine

[2] "In general in service Combined Cycle efficiencies are over 50 percent on an on a lower heating value and Gross Output basis. Most combined cycle units, especially the larger units, have peak, steady state efficiency efficiencies of 55 - 59%. " - http://en.wikipedia.org/wiki/Combined_cycle

[3] The US used to be the world supplier of rare earths, China just did a Wallmart on us and drove domestic suppliers out of business, the DoE has put them back into business - http://arstechnica.com/science/news/2010/12/us-rare-earth-mi...

Re: Chevy Volt: Is This Our Future?

#42

Post by mjb »

bbg wrote: post #19

I want to love electric cars, but I see two big issues: (1) if they go mass market, all that electricity will still have to be generated somewhere. Coal? Nuclear? (2) The batteries need rare-earth minerals, which are brought to market through environmentally-degrading open pit mining. Furthermore, at this point, most rare-earths are available almost exclusively from China.

> (1) if they go mass market, all that electricity will still have to be generated somewhere. Coal? Nuclear?

All of these alternatives are probably better than generating the same power, less efficiently, distributed over a fleet of small power stations ranging from fairly clean to horrifyingly dirty. There are large environmental advantages to centralized power generation, at least in the ease of regulation and emissions testing if nothing else.

Re: Chevy Volt: Is This Our Future?

#43

Post by pitdesi »

nhebb wrote: post #40

The $7500 tax credit is getting gamed by some dealers who resell the car to other dealers and take the credit for themselves. I don't know how widespread this is, but it's the kind of thing that makes my blood boil: http://www.msnbc.msn.com/id/43243050/ns/business-autos/t/som...

That turned out to mostly be a hoax: http://jalopnik.com/5806946/chevy-dealers-are-not-scamming-t...

Re: Chevy Volt: Is This Our Future?

#44

Post by georgieporgie »

masklinn wrote: post #33
georgieporgie wrote: post #27

Earlier quoted context omitted.

30mpg highway is really good and does not reflect the average experience of a consumer. That said, I think you're (sadly) right, but not for the reason you're stating. Because electric cars can't be recharged in five minutes, consumers will suddenly think they have to go even further on a charge. They will completely ignore the fact that they commute 15 miles each way, every day, and the fact that they already have t…

> 30mpg highway is really good Depends on the car you drive. 30mpg is really good for a gaz-guzzler, but mid-range sedans can easily be driven into the 40s.

mid-range sedans can easily be driven into the 40s.

Really? Here are some numbers from Kiplinger's "best midsize sedan" list from 2009:

* Sonata 32mpg highway.

* Mazda 6 30mpg highway.

* Chevy Malibu 33mpg highway.

* Nissan Altima 31mpg highway.

http://www.kiplinger.com/columns/car/archive/2008/car1207.ht...

Cars.com mentions the best in each class for 2011, and it's the Nissan Versa and Sentra, each at 34mpg for the "Midsize Cars" class.

Looking at FuelEconomy.gov, listed by class ("family sedan"), the only midsize sedans I can find that break 40mpg are the Passat diesel (43mpg) and the Hyundai Elantra (40mpg), the next highest is 31mpg.

Re: Chevy Volt: Is This Our Future?

#45

Post by waterlesscloud »

georgieporgie wrote: post #44
masklinn wrote: post #33

Earlier quoted context omitted.

> 30mpg highway is really good Depends on the car you drive. 30mpg is really good for a gaz-guzzler, but mid-range sedans can easily be driven into the 40s.

mid-range sedans can easily be driven into the 40s. Really? Here are some numbers from Kiplinger's "best midsize sedan" list from 2009: * Sonata 32mpg highway. * Mazda 6 30mpg highway. * Chevy Malibu 33mpg highway. * Nissan Altima 31mpg highway. http://www.kiplinger.com/columns/car/archive/2008/car1207.ht... Cars.com mentions the best in each class for 2011, and it's the Nissan Versa and Sentra, each at 34mpg for the…

I have no idea what the official rating is, but my 1998 Buick Lesabre gets about 31 highway on a consistent basis, and it's not even vaguely designed for efficiency.

Of course, city, which is where I live, is closer to 19 or 20.

Re: Chevy Volt: Is This Our Future?

#46

Post by arn »

daimyoyo wrote: post #12

I've said before and I'll say again: Electric cars will not gain widespread acceptance until you can travel the equivalent of a tank of gas on one charge. Tesla motors is close, but you need at least 300 and closer to 400 miles per charge.

I don't see the range as the issue, but the lack of instant refueling.

I don't get too worried about my car's total range since I can just stop and get gas every 10 minutes in town. But the problem with electric is that it takes 10 hours to recharge. Is there a solution to that besides hybrid gas/electric?

Re: Chevy Volt: Is This Our Future?

#47

Post by gamble »

dstein wrote: post #26

I've always thought the Volt sounded way over-engineered. Why bother with a fancy hybrid engine rather than concentrating on making a lightweight, affordable all-electric car? The simple approach is always going to win. Zenncars.com was taking this approach but I'm not sure of their progress.

It's all marketing. One day we'll look back and be amazed that people felt they needed to own two-ton 4WD land tanks with 500-mile gas tanks to buy groceries.

ZENN, however, won't be the ones to bring it about. Years back they abandoned producing vehicles for a weird penny-stock scam deal with EEStor.

Re: Chevy Volt: Is This Our Future?

#48

Post by gamble »

arn wrote: post #46
daimyoyo wrote: post #12

I've said before and I'll say again: Electric cars will not gain widespread acceptance until you can travel the equivalent of a tank of gas on one charge. Tesla motors is close, but you need at least 300 and closer to 400 miles per charge.

I don't see the range as the issue, but the lack of instant refueling. I don't get too worried about my car's total range since I can just stop and get gas every 10 minutes in town. But the problem with electric is that it takes 10 hours to recharge. Is there a solution to that besides hybrid gas/electric?

It's essentially impossible to charge a battery in the same time as filling a gas tank. The currents involved would be immense, and besides requiring heavy-duty conductors and power electronics, such high currents would incinerate any lithium-ion battery on the market today in spectacular fashion.

Battery swapping is probably the most practical solution, but developing a standard battery pack that can be used in a variety of models and easily swapped - not to mention the logistics and tracking to distribute them nation-wide - would probably take longer than developing higher-capacity batteries.

Re: Chevy Volt: Is This Our Future?

#49

Post by FrojoS »

ChuckMcM wrote: post #41
bbg wrote: post #19

I want to love electric cars, but I see two big issues: (1) if they go mass market, all that electricity will still have to be generated somewhere. Coal? Nuclear? (2) The batteries need rare-earth minerals, which are brought to market through environmentally-degrading open pit mining. Furthermore, at this point, most rare-earths are available almost exclusively from China.

An internal combustion motor is, at best, about 20% efficient [1], whereas if you burn the same fossil fuel in an electric power plant using a combined cycle configuration you can reach 60% [2]. Now the electric company loses some of that by sending over wires to your house (or where ever the charger is) but its still a big win. What that means in mathematical terms is that if you took the same fossil fuel we burn to…

I agree with your point, though I guess its probably more like 2x the cars. Also, in colder countries / states, the equation doesn't look as rosy. In winter, you use the heat generated by the combustion engine. Hence, efficiency goes way up.

Without knowing any numbers, I would assume, that at the moment, an additional, fossil fuel based, heating system would do the best job for an electric car. Webasto [1] for instance sells those.

[1] http://www.parkingheater.com/

Re: Chevy Volt: Is This Our Future?

#50

Post by axylone »

daimyoyo wrote: post #12

I've said before and I'll say again: Electric cars will not gain widespread acceptance until you can travel the equivalent of a tank of gas on one charge. Tesla motors is close, but you need at least 300 and closer to 400 miles per charge.

I really hope battery switching stations catch on (see betterplace).
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