The Rosamond Gifford Zoo is looking to become the first in the nation to be powered by its own animal waste — particularly the prodigious piles produced by its pachyderms.
The zoo — world prominent for its Asian elephant breeding program — is studying how feasible it would be to switch to animal waste as an alternative energy source to reduce its $400,000 annual heating and electricity bill.
The zoo's six elephants produce more than 1,000 pounds of dung per day, said Zoo Director Anne Baker.
"Zoos are about conservation and stemming the loss of animals and habitat," Baker said. "But conservation also is about how people use natural resources. This is an opportunity to give visitors the whole picture."
Depending on the process, the zoo animal waste could be used to produce methane or hydrogen for powering a fuel cell or generator.
$10,000 a year for disposal
The zoo sends most of its animal waste to a local farm, where it is composted. The zoo spends about $10,000 a year on animal-waste disposal, but Baker noted that method also requires the use of additional fossil fuels for transportation.
"This would be just such a good idea on so many levels," she said.
Although other zoos have come up with creative ways to reuse their elephant manure — including using it to make stationery — Rosamond Gifford appears to be the first to propose using it for power, according to Jane Ballentine, a spokeswoman for the American Zoo and Aquarium Association.
Baker said the idea of using animal waste for energy first arose several years ago when she was talking to local officials about the potential for creating a more environmentally friendly and self-sustaining zoo.
Because the elephants eat mostly hay, they are the ideal waste producers for the project, Baker said. Additionally, they are inefficient digesters, which makes their feces higher in energy content, she said.
The zoo also will look at using the manure from its domestic farm animals, its other hoof stock, such as its bison and caribou, and even its lions and tigers, she said.
Animal BTUs to be measured
In the United States, a number of farms have used animal waste to produce power, so the technology is available to apply at the zoo, said John Fox of Homeland Energy Resources Development, a New York City-based renewable energy developer assisting with the study.
But there are questions to be answered to know whether it can be worthwhile, he said.
The study will start by evaluating elephant dung BTU, a measure of its energy-producing potential as it decomposes or is burned. It will make the same assessment for other animals, and then consider whether it can be mixed with the elephant dung. Another important question, said Fox, is determining just how much animal waste the zoo produces.
The study is being directed by agriculture waste and manure-management specialists from Cornell University, Fox said. Engineers also will look at which buildings, and how many, could be powered by the animal waste, he said.