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Energizer Bunnies: Turning Rabbits into Green Fuel

4 minute read
Tara Kelly

Sweden’s Tommy Tuvuynger and his team of professional hunters don’t have to go far to find their prey. Tuvuynger is employed to keep down rabbit numbers in the Swedish capital, Stockholm. The rabbit population there has exploded over the past few years thanks to owners setting free their pets. Last year the eradication squad killed 6,000 of the furry critters, which are not native to Sweden. When the city started killing the rabbits in 2006, officials realized they would have to dispose of their carcasses. At around the same time, the European Union passed a law that makes it illegal to dispose of raw meat or carcasses in landfills. Solution: use the bunnies as fuel to heat Swedish homes.

When German newspaper Der Spiegel broke news of the novel fuel source last month, many Swedes were outraged. “It feels like they’re trying to turn the animals into an industry rather than look at the main problem,” says Anna Johannesson of the Society for the Protection of Wild Rabbits. Johannesson and other wildlife campaigners recommend spraying the park with a chemical that makes shrubs and plants unappetizing to the animals. Tuvuynger, though, has little sympathy for that argument. “If you do that you only move the problem 100 meters away. Overpopulation is not good for the animals’ well-being because they use up limited natural resources for survival, so shooting them is the only answer.”

(See pictures of 10 species near extinction.)

It’s not just rabbits that are being used to heat homes. Reindeer, moose, horses, pigs and cows are all thrown into an incinerator run by a firm called Konvex near Lake Vanem, southeast of Stockholm. Using a new method that was developed with the help of E.U. funding, raw animal material is crushed, ground and then pumped into a boiler where it is burned together with wood chips, peat or other waste to produce heat. “It is an efficient system as it solves the problem of dealing with animal waste and it provides heat,” says Leo Virta, the managing director of Konvex. “The main part of this fuel is coming from cows, pigs and moose. Rabbits are only a small part of the total volume. We take the raw animal material, mince it up into small pieces and add some formic acid. We then take the fuel and deliver it to the heating centers. One hundred thousand tons of raw material can generate enough heat for 11,000 homes a year.”

While killing animals to use them for fuel is rare in Europe, using animal by-products as fuel is now normal practice thanks to the E.U. law about disposal of raw meat and carcasses. Offal and other by-products must be incinerated or treated by approved waste-disposal companies. Not only does that help Europe meet its ambitious green energy targets, it also aids in the E.U’s bid to reduce landfill waste levels by 35% by 2020.

(See the top 10 green ideas of 2008.)

The law is already having an impact. In Britain, big supermarkets send unsold and expired meat to companies that convert it into fuel to heat homes. Since 2001, the German biofuel company Saria takes greasy animal fats and cooking oil from caterers and restaurants and then turns it into renewable energy used for power stations and manufacturing plants. Saria found using animal oil instead of vegetable oil is not only a cheaper alternative, but it also produces less harmful emissions, delivers better engine efficiency and reduces noise pollution.

Corporate America is getting into the animal-based biofuel market as well, thanks to U.S. government subsidies. Like Europe, the U.S. has a law that bans dumping raw meat into landfills. In July 2007, energy company, ConocoPhillips teamed up with meat giant Tyson to make biofuel from chicken and pork fats that would otherwise have been added into makeup, pet foods or soaps. Although biofuel produced from animal fat is better suited to fueling industrial boilers than cars, Tyson and ConocoPhillips have come up with a fuel for the “on-road” market.

(Read: “Tallying Biofuels’ Real Environmental Cost.”)

In Sweden, Tommy Tuvuynger takes a pragmatic view of the trend. “People like the rabbits because they are pretty. What else can we do with them though? We can’t give them bunny birth control pills. So we have to put the rabbits away.”

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