Svanholm Goes Carbon-Neutral

From Ecovillages

By Christina Adler Jensen, translated by Pauline Kreiken and Nicholas Mickelsen

(Nov/Dec 2009)

Svanholm, Denmark’s largest intentional community and ecovillage, is a collective with a multifunctional agriculture operation, including dairy cows and sheep, and the home of about 140 people. We began in 1978 when our founders bought 400 hectares (998 acres) on the island of Zealand, 55 kilometers (34 miles) from Copenhagen. Pioneers of organic farming in Denmark, we were instrumental in introducing organic dairy and other organic foods to Danish stores and supermarkets. About half of us work onsite — in maintenance, administration, farming, cooking, or teaching in our kindergarten, etc. — and half have jobs in the local area. As an income-sharing community 80 percent of each person’s income goes to Svanholm for taxes and common living expenses such as maintenance, food, electricity, childcare, etc.; 20 percent is kept for personal use. We’re also asset-sharing: new people contribute their assets to the community when they join (and which they get back if they leave). We make decisions by consensus.

We use off-grid energy and other ecologically sustainable systems. We currently produce 68 percent of our own electrical and heating energy needs through two wind generators and a slightly archaic wood-chip furnace (fueled mainly wood chips from by our own trees). Unfortunately, because we’re in a relatively isolated rural location, we’re largely dependent on gasoline-fueled cars for work and leisure activities, which burdens our conscience. In fact, 14 percent of Svanholm’s annual energy use is from driving cars! But this is about to change.

In the relatively near future electric cars will be available in Denmark it at a relatively decent price. Electrical recharging stations will be built along the entire Danish road system, ensuring a smooth transition from gasoline-powered vehicles to electric ones.

To power our electric cars in the winter, we installed a Stirling engine from the Stirling DK company in Denmark. This is a type of electric generator first developed by Scottish inventors Robert and James Stirling in 1816. The Stirling engine converts heat energy into mechanical power by alternately compressing and expanding a fixed quantity of air or other gas at different temperatures. (We use helium.) This pushes a flywheel around in a circle, which passes a copper coil back and forth through a magnetic field, which generates electricity. See animated graphics of different kinds of Stirling engines on Wikipedia.

Unlike internal combustion engines, Stirling engines are quieter, more reliable, and have lower maintenance requirements. A Stirling engine costs more initially and is usually larger and heavier than comparable internal combustion engines which produce the same amount of electricity, but a Stirling engine’s lower maintenance costs make up for it.

We plan to burn woodchips from our forest to power the Stirling engine. Roughly 20 percent of the energy produced by the woodchips will be converted into electric power; the rest will be used for heating hot water. (We plan to install huge water tanks next to the engine). The amount of wood chips required for this new project will be, on average, the same as that required by our current wood furnace. (In the summer we’ll get hot water from solar hot water panels, and electricity from our wind generators.)

This way in the winter we’ll provide our community with both hot water and electricity through a CO2 -neutral source, since trees yield only the amount of CO2 which they absorb through their lifetime. (Trees would emit an equal amount of CO2 through the process of breaking down if they were left to decompose on the forest floor.)

With a Stirling engine we’ll burn only 10 to 15 percent of our woodchips, and save an additional 15-20 percent on energy resources by replacing our hot water pipes with new, better-insulated pipes. The result should be a diminished use of wood chips and a more sustainable supply of electricity. In the near future we will also replace our out-of-date wind generators.

We’re looking forward to learning as we go with this new technology . . . and sharing the results with other ecovillagers.

Christina Adler Jensen is a journalist who has lived at Svanholm for three years. Pauline Kreiken is a social worker who has lived at Svanholm for 16 years; Nicholas Mickelsen is a working guest visiting from Canada.

A version of this article appeared in the Fall, 2009 issue of Communities magazine in the U.S.

For more information about Svanholm: http://www.svanholm.dk http://en.wikipedia.org/wiki/Svanholm

Related articles:

• How Yarrow Ecovillage Got "Ecovillage Zoning" —May '08
• Is The Farm an Ecovillage? — Oct '08
• L.A. Eco-Village Stops Bulldozers! — May '08
• Our Whirlwind Aussie Road Trip, Part I — May '09
• What Visiting Huehuecoyotl Taught Me — May '09
• What We Can Learn from Ecovillage Sieben Linden — Jan '09
• Whole Village Moves Ahead — Oct '08
• Will Earthaven Become a "Magical Appalachian Machu Picchu"? — May '09
• "In Grave Danger of Falling Fruit" — Jan '09