From a presentation by Michael Vickerman to Sierra Club – Great Waters Group in Milwaukee, WI on October 17, 2011:

The most agonizing decisions that await us will involve determining which elements of our built environment can be supported with renewable energy and which elements cannot. With a lower EROEI (energy return on energy invested), we will not be able to run a world that formerly ran on cheap, abundant fossil fuels. We have little choice but to downsize our buildings, downscale our communities, and reorganize the economy.

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