Bill Menke's BLOG Page: Hybrids, yes; electrics, no.
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Back in the 1970's my spouse and I had a little Japanese sedan that routinely performed at 35 miles per gallon. Only a few of today's gasoline-powered cars, such as the Honda Civic, get that kind of mileage. Our eagerness for high-powered cars with lots of pep and lots of accessories has eclipsed the quest for fuel economy (safety and anti-pollution considerations have contributed, too). Hybrids are the exception. |
The high fuel economy of a hybrid, such as the Toyota Prius, derives from its low-powered engine. Its peppiness comes from the assist that its electric motor provides during those critical moments, such as accelerating during passing, when power (or the lack of it) is most noticeable. And since the assist is only needed momentarily, the battery can be small, recharging during the longer periods when no assist is needed. (The Prius' battery, alone, could power the car only for about 5 miles).
Hybrids are thus an eminently sensible way to recover the high-mileage glories of my 1970's Japanese sedan, without having to sacrifice performance. I'm suprised that so few auto manufacturers are offering them. I suppose that the hang-up is price - any vehicle with two power systems is bound to be more expensive than a vehicle with only one (and, indeed, the Prius is about 30% more expensive than the Civic). Manufacturers must doubt people's willingness to pay up-front for whatever savings high fuel economy eventually brings.
The utility of electric vehicles is less clear to me. Superficially, the economics seem to work. The Tesla Roadster (which I take as representative) is advertised with an efficiency of 28 kWh per 100 miles. That's $2.80 per hundred miles for the electricity, at the typical price of $0.10 per kWh. That's perhaps only 30-50 percent the cost per mile of gasoline. The problem is the impact that widespread use of electric vehicles would have on the electric power industry (and on those of us who pay for that electric power).
A typical car is driven 12,000 miles per year, or 1000 miles per month. An electric car would this use 280 kWH per month, or 644 kWh per household, given that the average household has 2.3 automobiles. US residential electricity consumption is 920 kWh per month, so switching to electric cars increases residential electric usage by 70%. That's a lot of electricity! Producing and delivering that much extra electrical power would be a problem. Hundreds of new power plants would need to be built and tens of thousands of miles of power lines would need to be upgraded. The cost would no doubt be spread over all power users, not just electric car owners.
In the US, electrical power comes 50% from coal, 20% from natural gas, 19% from nuclear, 7% from hydro, 2% from oil and 4% from everything else (including solar and wind). Coal would inevitably be the major fuel for new generating capacity, at least for the foreseeable future. Increased use of coal is undesirable from two perspectives. Coal mining is much more environmentally destructive than petroleum extraction (think mountaintop removal). And coal releases the most carbon dioxide (a greenhouse gas) per kWh of all fossil fuels.
All this is not to say that buying an electric car is necessarily a bad choice. They're attention-getting, and the designs are cool. I'd love a Tesla Roadster (should one ever be given to me). But in large numbers electric vehicles would create far-worse problems than they solve. So, a nation full of electric cars? No! Of, hybrids? Yes!
