By Jody MacPherson
Originally appeared in C3 Views (Climate Change Central newsletter) in September, 2003
For farmers struggling with severe drought and the recent case of bovine spongiform encephalopathy (BSE) – or “mad-cow disease” – in Alberta, sinking large sums of money into manure might not sound very appealing.
Lynda Skene, a partner in Genesis Projects Ltd., admits it’s a tough sell. Her company, based out of Calgary, provides consulting services to the agricultural sector.
“I’ve almost given up trying to convince agricultural producers to look at anaerobic digesters on their own,” she admits.
Still, Skene can give a lot of good reasons to get involved in this “biodigester” technology that uses dung-devouring bacteria to create energy from manure.
“It eliminates up to 90 percent of odours, which is the biggest issue neighbours have with feedlots,” she says.
Skene says the process also gets rid of most pathogens – the agents that cause disease – another hot topic since contaminated water in Walkerton, Ontario killed seven people and sickened hundreds more.
“There’s a lot of interest out there,” she says. “But the average agricultural producer just can’t afford it on their own. The technology is expensive and they are stretched to the limit.”
“They’re not looking for a huge profit, but they don’t want to lose money either.”
A bit of government assistance would be helpful, says Skene, although she suggests a “combined” approach. She says money is needed in the form of a direct subsidy to implement the technology and then an enhanced power purchase plan as an incentive.
“The government could purchase a power contract with companies like Epcor or Enmax and add two cents (per kilowatt hour) to producers sending power to the grid to enhance the viability,” she says. The going rate is around five cents per kilowatt-hour.
According to one estimate by the Alberta Research Council, about 20,000 head of cattle in a feedlot could generate an average of about 332 Megawatts of electricity or revenue of $111 million annually. When it comes to heating, the same size herd could generate an average of 404 Megawatts, or revenue of $135 million.
But even the most optimistic proponents recognize the initial investment would have to be huge.
“The return on investment is marginal at best,” says Skene. “Most would be lucky to break even let alone make a profit.”
Although small operations have used the technology successfully in Europe, Skene believes you must have a large operation to make it work.
“It’s very popular in Europe but it is subsidized by the government,” she says. “They receive about 15-20 cents (Cdn) per kilowatt hour in subsidies, compared to energy prices here of three or four cents. We would need about five to eight cents to make it viable.”
Skene says researchers are working to make the equipment more affordable and gives the example of the costly stainless steel tanks used in the process. Scientists are experimenting with different types of holding tanks made with less expensive materials.
Water shortages are becoming more of an issue as well. According to Skene, “there are areas in Alberta where they can’t build livestock operations because there isn’t enough water.”
“To be viable, there must be a zero discharge system where the water can be treated back to potable. Again, the technology is there to do it, but it’s expensive.”
There is also new technology being “cooked up” by researchers. It’s known as “pyrolysis” and Skene says it goes further than digestion, applying pressure as well as heat to the waste to get rid of a lot more mass. It has a lot of potential, she says, but it’s still in the very early stages of development.
Farmers are also waiting to see what happens with emissions reduction credits, but Skene says most believe there are too many issues still “up in the air.”
Under the rules of this new international marketplace, credits are awarded for reducing greenhouse gas emissions. Those credits can then be sold to others to help meet their own targets.
Converting manure with biodigester technology prevents greenhouse gases from being released into the atmosphere, allowing those who use it to earn credits that can then be sold on the open market.
“The credits could become another revenue stream, but we’re not there yet,” she says.
Ian Potter, Director of Sustainable Energy Futures for the Alberta Research Council also has a word of caution for farmers wondering about economics.
“If you need the emission reduction credits to be viable, I would stand back from the project,” he says. “It should be able to work on its own.”
Still, both agree revenue from emission reduction credits would add a lot of voltage to the manure to energy idea.
Skene says she is now turning her attention to “clusters” of clients from different sectors beyond the agricultural industry in an effort to create economies of scale.
“It takes some creative thinking but basically what we need to do is add in other materials with the manure to enhance the production of the bio-gas,” she says. “A digester is like anything – you get out what you put into it.”
By adding high fat and protein products to the manure concoction, the efficiency of the energy production is enhanced. For Skene, the challenge is more biological than mechanical. Or as one veteran American scientist told her, “Girlie, what you need is a cook!”
Under partnership arrangements like one she is currently working on in British Columbia, the ingredients for this bio-gas “stew” would come from slaughterhouses, municipal waste facilities and even retail businesses like grocery stores which have tonnes of food waste to get rid of every day.
Skene says for every tonne of manure, 30 cubic metres of biogas can be produced. But just by blending in cooking oil, the biogas increases to 400 cubic metres per tonne.
The recipe for success also requires cooperation and support from the public. Skene points out there has recently been a lot of backlash in Alberta against feedlots in particular and the public doesn’t want to see them in the community.
“Instead of forcing feedlots out into the middle of nowhere, the facilities need to be close to each other to be cost effective,” she says.
With some interest from Alberta already evident, Skene says she hopes to replicate the B.C. project in this province in the near future.