Cash for Clunkers: The Environmental Cost of a New Car

[JonQ]

The short answer: 31,362 Btus per pound. That’s the average energy cost for constructing a modern motor vehicle —rubber, fluids, glass, metal and battery. Can that number tell you if it’s better, environmentally speaking, to keep your ’85 Renault Fuego or pick up a Honda Insight? That’s a longer answer full of scary science and scarier math. The U.S. Department of Energy’s Argonne National Lab has attempted to analyze the energy consumed manufacturing vehicles. Their creation is called Greenhouse gases, Regulated Emissions and Energy use in Transportation models. GREET. No really.

Argonne broke automobiles down to discrete parts, then measured the energy required to mine, make and move those parts. They assess in British thermal units, the amount of energy needed to raise the temperature of one pound of water one degree Fahrenheit.

Applying the GREET model, it takes 100.391 million Btus to make a 3,201-pound vehicle. Not all cars are created equal, but the model accounts for the differences. For instance, the batteries in a hybrid render a different formula. According to GREET, a Prius comes in at 38,650 Btus per pound. A 2009 BMW M3, with its light carbon fiber roof screws things up. Just ignore it. For the 90 percent of the vehicles on the road, it’s 31,362 Btus per pound.
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http://www.thetruthaboutcars.com/cash-for-clunkers-the-environmental-cost-of-a-new-car/


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An interesting analysis. It seems for many of the cars traded out the cash for clunkers program has led to a net gain in pollution, despite higher efficiency standards.

[NYC_SKP]

1. Your closing statement, a net gain, may not take into account the difference in useful vehicle life.

If my Prius is compared to my 85 Caprice, but the fact that the Prius has 250,000 miles to go compared to 50,000 for the Caprice, doesn't that influence the comparison?

:shrug:

[JonQ]

2. Yep

my point wasn't that trading in an old car for a new one is always a bad deal, clearly that isn't the case.

I was merely offering a riposte to the assumption that destroying an older car and replacing it with a newer one will always yield a net reduction in pollution. Sometimes it's better, sometimes it isn't.

[NYC_SKP]

3. True, and it make the argument for mfgrs to make not only efficient cars, but also...

long-lasting ones without the designs and materials that make them near impossible to maintain after 10 or even 5 or 6 years.

Meanwhile, there are plenty of 1944 Willys MB Jeeps and the like still running, and model As!!!

:toast:

[Mnpaul]

4. Of course it is better for the environment to keep your ’85 Renault Fuego

They were broken down most of the time. Some people have to get to work every day so it is not a very good idea to keep it.