How Green Is Your Car?
Interesting findings from a three-year investigation by Oregon-based CNW Marketing Research measures the environmental impact of cars from the time they're built until the moment they're scrapped using what the firm calls a "dust to dust" analysis. Apparently Volvo tried to do this previously but gave up due to the complexity of the analysis.
CNW collected 400 data points ranging from the energy consumed in research and development to energy consumed in junkyard disposal for each of 100 makes and models of cars and trucks. In addition, it considered the electrical energy needed to produce each pound of parts. It calculated greenhouse gas emissions. It calculated mileage, too - adjusting for the differences between rush-hour Tokyo and rural America.
The company expresses energy requirement as the dollar cost of energy for every mile across a vehicle's anticipated years of use. The measure is called "U.S. dollars per lifetime mile."
This presents a better picture of the overall energy consumption for a vehicle rather than just fuel consumtion. The results are shocking (to me anyway). For instance, it reports the lifetime energy requirement of a Hummer as $1.90 a mile, and the lifetime energy requirement of a Prius as $2.86 a mile. Makes you go "hmmmm...." doesn't it?
CNW executive Art Spinella says: 'Why do hybrids show up so poorly? It's because of the manufacture, replacement and disposal of high-energy-use items including the batteries and electric motors and lighter-weight materials used in construction.
'On the other hand, simpler vehicles such as the Jeep Wrangler use established technologies that need less energy in manufacture and many parts that are shared among other vehicles, again reducing the energy used in manufacture. They also have a longer life cycle.
'We believe that basing purchase decisions solely on fuel economy or vehicle size does not get to the heart of energy usage.'
Of course, car manufacturers disagree with the findings stating that the analysis is too biased toward the production of the vehicle and not its operation.
Edit: August 6, 2007
Well, I went to read the entire document and well...um... Let's just say it isn't very convincing. While the author makes interesting claims, the document isn't written in a manner that is consistent with good scientific investigation. Anyone that has taken high school level science will find that there is little in common with the open application of scientific method. While there is the appearance of being unbiased, none of the data collected is shared and there is little disclosure of the methodology employed in coming up with the results. Indeed, in this light, most of the results must be seen as arbitrary rather than conclusive.
Until there is full disclosure of the data, documentation on how it was collected, and the methodology used in this investigation, there is very little to recommend this study. I'd take the conclusions drawn by the author with a grain of salt...