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A Musing Environment
A Friend looks at (mostly) the environment: “Let all nations hear the sound by word or writing. Spare not place, spare not tongue, nor pen…This is the word of the Lord God to you all, a charge to you all in the presence of the living God; be patterns, be examples in all countries, places, islands, nations, wherever you come; that your life and conduct may preach among all sorts of people, and to them. Then you will come to walk cheerfully over the world, answering that of God in every one…Spare no deceit.” George Fox
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A Friend’s Path to Nuclear Power
September 27th, 2008
The October 2008 Friends Journal focuses on Energy, Climate, and Building Community, and includes my article, A Friend’s Path to Nuclear Power. The footnotes were too many and too long for the print article, so we are posting the article here. Comments on this or other articles in this issue?

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Green Futures
August 26th, 2008
Another UC, Berkeley Forefront magazine article discusses Green Future: Engineers Forge Novel Technologies For A Sustainable World.

Environmental Footprints: Sustainability by the Numbers

When given a choice—paper or plastic, cloth diapers or disposables, garbage can or recycling bin—most of us do what we think is greenest. The problem is, we’re often wrong.

“We make emotional decisions, but often there’s no scientific proof to back things up,” says Arpad Horvath, professor of civil and environmental engineering. For several years Horvath has focused on developing systematic methods to assess the environmental impact of our industrial processes, consumer goods and services and beyond…

In a 2004 study, for example, Horvath’s assessment revealed that reading the New York Times wirelessly on a PDA instead of having the paper delivered to your door requires consumption of about 140 times less carbon dioxide and 26 to 67 times less water. Now he is bringing his research to bear on the building industry, examining a building’s sustainability in the context of the entire supply chain behind its construction, operation, maintenance and end of life.

“Besides transportation and electricity generation, buildings are the single greatest consumers of energy and other resources,” he says. “And nearly every sector of our economy—mining, manufacturing and services—supplies to the building industry.”

Tiny Generators: Recapturing Waste Heat

Almost all the world’s power, roughly 10 trillion watts, is produced by burning fossil fuels and running engines based on heat. For every watt of power generated, one and a half watts are dumped as waste heat. It’s a law of thermodynamics.

“Can we extract some of the juice from that waste heat?” asks mechanical engineering professor Arun Majumdar. He and his colleagues are working at the nanoscale to build super-efficient devices that directly convert heat into electricity. Their research could some day lead to hybrid automobiles that generate electricity from the radiator to charge their batteries, or homes powered by extracting energy from their walls or the ground they stand on.

“When you generate 10 trillion watts of power, you’re wasting a staggering 15 trillion watts,” Majumdar says. “Extracting even a fraction of that would amount to huge fuel savings and reductions in carbon dioxide emissions.”