The Amazon Kindle is a compact device that uses e-ink display technology that doesn't consume power when displaying a static image. The act of reading a book generally involves long views of static images. As a result, the Kindle can achieve very long battery life when used for normal reading.

In a continuing trend to examine everything possible with a green magnifying glass, the Cleantech Group has recently released a report about the effective carbon footprint of Amazon's Kindle eReader. In particular, they compare the carbon footprint of the Kindle to the carbon footprint generated by reading the same amount of books on paper. Since the release of the Kindle, this question has been posed a number of times, but this is the first comprehensive report to take an at least somewhat rigorous approach to the problem.

In order to view the report, you need to be a member of CleanTech. However, a report by Earth2Tech summarizes the findings nicely. In short, given the assumptions by the report authors about the reading and purchasing habits of the typical reader, using a Kindle instead of buying paper books should save an average of 168kg of CO₂ per year.

This report, and the subsequent questions raised by it underscore a common sticking point in ecological impact analyses: the big picture. The resource consumption of a particular device or action must not be taken in isolation—as we see in this report. Furthermore, while reducing carbon footprint is a laudable goal, the carbon output of a process is not the only negative consequence of consumer production. In the case of the Kindle vs. Paper Books argument, think of all of the contributing factors: manufacturing and shipping costs, consumer travel time (no travel is required to get a book on your Kindle), disposal costs and consequences.

One should wonder, upon reading the summaries of this report, if proper assumptions were made. For example, the report considers the carbon footprint associated with needing to drive to the store to buy a book (which doesn't exist for the Kindle). But does it take into account that the driver may be on a route taken every day regardless of the book purchase? Does it consider that books often come by mail now? How about the fact that people share books?

The ecological analysis of datacenters cane easily become similar complex. When evaluating energy-saving and cost-saving measures in the datacenter, one should perform an in-depth analysis about as many aspects of an action as possible, to determine if the outcome will be a net positive not just for your organization, but for the environment.