Sunday, December 21, 2008

EarthTalk: Eco-Villages; Drive or Fly?

Dear EarthTalk: What are “eco-villages?” I’ve heard of one in New York near Ithaca and another one called Arcosanti being built in Arizona. -- Jim Killian, Brookline, MA

Eco-villages are essentially designed communities intending to be socially, economically and ecologically sustainable. Environmentalist Joan Bokaer developed the vision for the first eco-village, which would eventually be built on the outskirts of Ithaca, New York, while on a continent-wide walk for sustainability across the United States in 1990. In Context magazine publisher Robert Gilman helped refine the concept through his research, writing and speaking on the topic. In 1996, the first residents moved into the EcoVillage at Ithaca, and a movement was born. According to the nonprofit Global Ecovillage Network, some 420 eco-villages exist in both urban and rural settings around the world today.

The defining characteristics of an eco-village, according to Robert Gilman’s seminal 1991 article, “The Eco-Village Challenge,” include “human-scale, healthy and sustainable development, full-featured settlement, and the harmless integration of human activities into the natural world.” Gilman also said that eco-villages should limit their populations to 150 individuals, which is the maximum size for any working social network according to the teachings of sociology and anthropology.

While the term eco-village did not come into common usage until the 1990s, the concept may in fact be older. Arcosanti, a self-described “experimental town” in the high desert of Arizona, 70 miles north of Phoenix, has been under construction since 1970 and eventually will be the home of some 5,000 forward-thinking residents. In keeping with the concept of clustered development so as to maximize open space and the efficient use of resources, the large, compact structures and large-scale solar greenhouses of Arcosanti occupy a small footprint—only 25 acres—within the community’s 4,000-acre “land preserve.”

Italian architect Paolo Soleri designed Arcosanti according to his concept of “arcology” (architecture + ecology), whereby, in his words, “the built and the living interact as organs would in a highly evolved being.” Underpinning the concept is that “many systems work together, with efficient circulation of people and resources, multi-use buildings, and solar orientation for lighting, heating and cooling.”

Those interested in learning more can attend a four-week workshop at Arcosanti to study building techniques and arcological philosophy, while getting a chance to contribute to the city’s ongoing construction. To date, some 5,000 participants have all had a hand in the construction of Arcosanti.

Some other “intentional communities” designed with sustainability in mind around North America include Cobb Hill in Vermont, Vegan in Hawaii, Dancing Rabbit in Missouri, Maitreya in Oregon, Dreamtime in Wisconsin, Paz in Texas, Earthaven in North Carolina, Prairie’s Edge in Manitoba and Kakwa in British Columbia. For information on these and other eco-villages, the Ecovillage Network of the Americas as well as the Global Ecovillage Network offer extensive resources for free online.

Dear EarthTalk: How can I determine if it is more eco-friendly to fly or drive somewhere? -- Christine Matthews, Washington, DC

The simple answer is that driving in a relatively fuel efficient car (25-30 miles per gallon) usually generates fewer greenhouse gas emissions than flying. In assessing the global warming impact of a trip from Philadelphia to Boston (about 300 miles), the environmental news website Grist.org calculates that driving would generate about 104 kilograms of carbon dioxide (CO2)—the leading greenhouse gas—per typical medium-sized car, regardless of the number of passengers, while flying on a commercial jet would produce some 184 kilograms of CO2 per passenger.

What this also means, of course, is that while even driving alone would be slightly better from the standpoint of greenhouse gas emissions, carpooling really makes environmental sense. Four people sharing a car would collectively be responsible for emitting only 104 kilograms of CO2, while the same four people taking up four seats on a plane would generate some 736 kilograms.

Journalist Pablo Päster of Salon.com extends the comparison further to a cross country trip, and comes to similar conclusions. (Differences in the math are attributable to the use of slightly varying assumptions regarding fuel usage and source equations.) Flying from San Francisco to Boston, for example, would generate some 1,300 kilograms of greenhouse gases per passenger each way, while driving would account for only 930 kilograms per vehicle. So again sharing the drive with one or more people would lower each individual’s carbon footprint from the experience accordingly.

But just because driving might be greener than flying doesn’t mean it always makes the most sense. With current high gas prices, it would cost far more in fuel to drive clear across the United States in a car than to fly non-stop coast-to-coast. And that’s not even factoring in the time spent on restaurants and hotels along the way. Those interested in figuring out driving fuel costs can consult AAA’s nifty online Fuel Cost Calculator, where you can enter your starting city and destination as well as the year, make and model of your car to get an accurate estimate of what filling ‘er up will cost between points A and B.

Once you’ve made your decision whether to drive or fly, consider purchasing carbon offsets to balance out the emissions you are generating with cash for renewable energy development. TerraPass, among others, makes it easy to calculate your carbon footprint based on how much you drive and fly (as well as home energy consumption), and then will sell you offsets accordingly. (Monies generated through carbon offsets fund alternative energy and other projects, such as wind farms, that will ultimately take a bite out of or eliminate greenhouse gas emissions).

Of course, an individual’s emissions from riding a bus (the ultimate carpool) or a train (many of which rely solely on electric power generated by their own motion) would be significantly lower. Paster adds that a cross-country train trip would generate about half the greenhouse gas emissions of driving a car. The only way to travel greener might be to bicycle or walk—but the trip is long enough as it is.

GOT AN ENVIRONMENTAL QUESTION? Send it to: EarthTalk, c/o E/The Environmental Magazine, P.O. Box 5098, Westport, CT 06881 or e-mail: earthtalk@emagazine.com. Read past columns at: www.emagazine.com/earthtalk/archives.php

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