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  • Hybrids require more energy than Hummers?

    Posted on July 6th, 2007 Lee Devlin No comments
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    I’ve read several references to a report that alleges that the total energy costs per mile of a hybrid vehicle exceed that of an H3 Hummer, and by a significant margin too, more than 50%. I decided to look up the source of this information and found a 450+ page report filled with spreadsheets on various costs it takes to run a vehicle over its life expectancy and beyond. There was a lot of interesting information in the report, like how many miles a typical vehicle is driven before being recycled, how much money is spent on repair, how much it costs to recycle, as well as a lot of feedback and industry reports attached to th end of it.

    Manufacturers estimate that the energy used to produce a vehicle is about 20% of the amount of energy it burns in fuel over its lifetime. The fuel cost over the life of a vehicle is easy to compute. For example, if a car gets 25 miles to the gallon, and is driven 180,000 miles before it’s recycled, it would use about 7200 gallons of gasoline, and at a cost of $3.00 per gallon, this would come out to $21,600 or $.12 per mile, which seems quite believable. Add to that another 20% for the energy required to produce the car ($4320) or $.02/mile and you have a total energy cost of roughly $.14 per mile. This value seems plausible, although it doesn’t include the recycling energy cost which one might assume is on the same order of magnitude as the energy cost to produce the vehicle.

    However, the report, available for free from CNW Research, estimates that most of the energy used by a vehicle comes not from the energy to produce it and to power it over its lifetime, but rather from the recycling cost and that accounts for most of their $3.238 per mile estimate for a Honda Civic Hybrid and $1.949 per mile estimate for an H3. A Honda Civic Hybrid is one of the most fuel efficient vehicles on the road whereas an an H3 is a very large SUV and gets about a quarter of the fuel economy of the Hybrid. So it’s hard to imagine an inverse relationship in energy cost per mile, and why would the real energy costs exceed the ‘apparent’ energy costs by not just a factor of 2 or 3, but more than 20 times? The report suggests that the amount of energy used in recycling is related to the ‘complexity’ of the vehicle and that the complexity of hybrids makes them much more expensive to recycle than a simpler vehicle that has been in production for a longer period of time.

    After combing through the entire report and seeing numbers calculated out to such a high degree of precision, yet showing no calculations for the actual recycle costs, I can only conclude that they must be a guess.

    A manufacturer has to have a pretty good idea of how much energy goes into a vehicle’s manufacture. After all, they have to sell the car for well more than just the energy that goes into it or they’d go broke in a hurry. The same is true for their part suppliers. Similarly, a recycler wouldn’t take a car for recycling if the value of the material derived from it would be completely be overshadowed by the energy cost it would take to recycle it. Much of the material gets recycled from a vehicle simply *because* it’s cheaper to used recycled materials than it is to process the material from scratch. If this were not the case, these materials would end up buried in a landfill, end of story. So saying that the recycle cost exceeds the original vehicle’s cost and all of its apparent energy usage by an order of magnitude or more simply makes no sense.

    The research seems to indicate that the recycle costs are somehow hidden in the operating costs and profits of other businesses but that similarly makes little sense. Surely the report wouldn’t intend to count the energy cost to produce a single car as somehow having to include the costs of other cars that may be produced by that same material after it’s recycled. That would would be not just double or triple counting energy, but counting the energy for each recycling operation against the original vehicle for all eternity. Again, that would make absolutely no sense.

    So my conclusion is that the research is flawed and the only reason it gets any attention is because it alleges something that anti-environmentalists find so outrageously compelling, i.e., that H3’s are more environmentally friendly than hybrid vehicles. And I write this not as a hybrid car owner, but as an owner of a 15 mpg SUV. I just don’t like research that gets so many references without being critically examined.

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