I was reading an article about Priuses in the New York Times (online) that caused me to think, once again, about something I find very troubling about all the discussion of reducing the carbon footprints of the automobiles we drive, about legislating improved mileage and/or offering incentives to buyers of lower-carbon-footprint cars. And it is this: what about the carbon footprint of the manufacturing process? What about other environmental impacts of new cars? Bear with me, while I try to think this through.
Suppose I have a Hummer. It's a nice, ecologically disastrous beast, with a very high carbon footprint, that I bought in a solipsistic moment some years back. I don't know enough to actually assign a meaningful number to its day-to-day carbon footprint, but lets say its daily value is "10." So, one morning, after a long talk with some friends, I wake up feeling guilty, and decide to buy a Prius. So I buy the Prius – and lets say, for the sake of argument, that its daily carbon footprint is "2" – i.e. it puts out 20% of the ongoing emissions as the Hummer.
But what was the carbon footprint of manufacturing the Prius? Is it unreasonable to imagine it might be some rather large number compared to the daily value? I mean, just the delivery from manufacturer to dealer is going to be some largish multiple of the daily footprint, e.g. 20 or 50, right? There's steel, engine, tire manufacturing. And farther back, there's high-paid executives and designing engineers at Toyota and their contractors, sitting in air-conditioned offices over years, making the Prius a reality. ALL of that is part of the vehicle's carbon footprint. Is it unreasonable to imagine that the carbon footprint of the creation of that new Prius might not be, say, in the 1000's? 10,000's? What if I go out on a limb, and guess, say, 8000 "units"?
The consequence is as follows: I'm reducing my personal carbon footprint, by switching from Hummer to Prius, by 8 units per day. But the Prius' manufacture entailed a footprint of 8000. So, that means I will have to own the Prius for 1000 days before I "break even" in terms of carbon footprint. That's almost 3 years! Wouldn't it be better for the environment to urge people to KEEP their current cars longer, rather than switch out to lower-footprint vehicles? This would be true regardless of the type of vehicle they currently own.
And I understand very well, I just pulled these numbers out of a hat, and the analysis could be extremely mistaken. But what I wonder about, is why don't you ever see anyone doing this kind of analysis, in the media? And there are other issues – the Prius has a contingent of non-carbon-related environmental issues, around its high-tech manufacturing processes, and its massive array of batteries – these are not in any way resolved. What about battery disposal? What about the toxics involved in battery and plastics manufacture?
I cannot argue that in terms of real, long-term life-of-product carbon footprint, my father's 1928 Ford Model A is lower than almost anything else on the road (or, er, in storage, at the moment), because of its under 20 mpg and "dirty" exhaust. But it nevertheless represents maximizing the utility of the manufactured object vis-a-vis its intended purpose. The carbon footprint of the car's manufacture has amortized for 80 years now! Meanwhile, that self-righteous bastard driving the 2008 Prius, which replaced his 2005 Corolla, which replaced his 2000 VW, which replaced his 1992 Chevy, etc., etc., has left a landscape strewn with massive-manufacturing-footprint disposed-of vehicles. If he had kept each of his earlier vehicles for three or four years longer than he did, and avoided the Prius completely, he'd probably do more to reduce his carbon footprint than a lifetime's worth of Prius driving.
I'm going to call this problem the problem of "carbon amortization."
Below, is a picture of my mom, my sister, and me, with the family car, somewhere in Oregon, 1970.
My father still has this car. He hasn't had it running in a few years, due to financial constraints, but I know he intends to drive it many more miles – as do I.