> If you look at the energy expenditures for maintaining a library over a decade, let alone a century, a paper book would be far more environmentally friendly.

> If you look at the energy expenditures for maintaining a library over a decade, let alone a century, a paper book would be far more environmentally friendly. I suspect that the energy cost of maintaining a paper book at a decent temperature for a decade would be orders of magnitude worse than the energy cost of backing up an ebook for a decade. My concern is that after a decade, all mirrors of the ebook might disappear.