Manure biogas developer ready for round two as green power trend grows
July 10, 2008 by Tony Kryzanowski
Grant Meikle’s first attempt, in
2001, at developing a project to produce electricity from burning
biogas generated from the anaerobic digestion of manure may not have
gone exactly according to plan, but he is far from ready to throw in
the towel on this technology. He says a lot has changed in seven years.
|Grant Meikle of Open Energy admits his first attempt at developing a manure- to- electricity project did not turn out exactly as he planned, but he is not ready to throw in the towel on the technology.|
Grant Meikle’s first attempt, in 2001, at developing a project to produce electricity from burning biogas generated from the anaerobic digestion of manure may not have gone exactly according to plan, but he is far from ready to throw in the towel on this technology. He says a lot has changed in seven years.
“It’s a huge industry and we plan to be a small part of it,” he says from his office in Salmon Arm, British Columbia, where he operates Open Energy Inc., a company currently specializing in alternative energy project consultation. “I’ve noticed that there’s a lot more activity by others getting involved in the biogas industry and that’s great.”
He is pleased that legislators now seem more willing to take action to remove hurdles for independent power producers to tie into existing power grids and are encouraging investment in projects like anaerobic digestion of manure to produce biogas.
For example, Alberta has just announced new micro-generation regulations that came into effect on February 1, 2008. A leader in de-regulation of power generation and distribution, the new regulations will allow Alberta residents to generate their own power and gain credit for any power they do not use by sending it to the provincial power grid. “I think it is a very positive thing from the point of view of a promoter of independent power,” says Meikle. “Any barriers you can bring down certainly increase the viability of power generation plants as well as creating interest in the overall industry.”
His company is close to completing a feasibility study on a second agriculture-based biogas power generation project, with Meikle feeling that the timing for such a project is a lot better this time around than in 2001. Back then, he was based in Ponoka, Alberta, working as an electrical contractor for the agriculture industry, primarily designing systems, organizing site preparation and wiring large intensive livestock barns.
Manure management was an issue on just about every project because objections voiced by the public to projects proposed for their immediate area often delayed the issuance of development permits. Even when intensive livestock operators were able to provide an acceptable manure management plan, it did not seem to be enough for surrounding residents, who were primarily concerned with odor issues. So Meikle started looking for better manure management solutions for intensive livestock operations. At the time, Alberta had two million hogs, six million cattle and 255,000 sheep, so he felt there was a well-established potential customer base for a ‘greener’ approach to managing manure.
|The technology to capture biogas from hog manure, imported to North America from Luxembourg by BioGem Power Systems, creates a pathogen-free dry compost as one by-product. It has been used as organic manure or dairy barn bedding.|
|The Iron Creek Hutterite Colony was the first to apply the BioGem Power Systems anaerobic digester technology in North America, but low power rates and internal water supply issues made the project difficult to justify after three years in operation. These vessels are now used for manure storage.|
“We thought the biogas concept was one way that allowed producers to either build or expand without having the odor impact on the community at large,” says Meikle, “as well as giving the producer the opportunity to have an additional revenue stream from use of the manure.”
The solution presented itself by adapting European-developed anaerobic digestion technology specifically from the tiny principality of Luxembourg to North American conditions. To market the technology, a group of investors founded BioGem Power Systems, with Meikle working as vice-president of marketing and sales. What became obvious from the company’s research into anaerobic digestion was just how much more advanced Europe was in terms of actual, proven anaerobic digestion installations and biogas generation facilities attached to intensive livestock operations. For example, the Luxembourg technology developer already had more than 100 of its systems installed mainly in Europe. Today, that number is more than 130.
Meikle believes that the Europeans are at least 20 to 25 years ahead of North America when it comes to power generation from biogas produced from anaerobic digestion. Three factors spurred the growth of biogas generation technology in Europe. These were high energy costs, coupled with government subsidization of technology and project development, and an established market for green power through legislated targets mandated by government.
When BioGem Power Systems opened for business, it was nearly the only company offering this technology in North America to a public that was still hesitant to embrace what was still a little understood manure management method. Venture capital was very hard to find because so many people were sitting on the fence on the whole issue of green power, whereas now, Meikle says there are many more individuals investigating the actual viability of various green power options.
The company experienced a breakthrough when it convinced the Iron Creek Hutterite Colony near Viking, Alberta, to invest in a BioGem biogas system. The BioGem anaerobic digestion system would produce enough biogas to fuel an eight cylinder piston engine that would in turn drive a 350 kilowatt (kW) generator around the clock. Enough power would be generated to supply the needs of the 60 member colony as well as surplus power sold on the provincial power grid to offset the cost of installation.
The Iron Creek Colony represented an excellent launch point for this anaerobic digestion project because it had an established pork production business, managing 600 breeding sows that averaged about 30 offspring in two to three litters per year. The average manure output from the barn was about 12 million liters per year. The hog operation was producing about 88 cubic meters of manure slurry per day – well within the minimum requirement of about 70 to 80 cubic meters per day for the project to be feasible. As a general rule, higher energy rates reduce the minimum daily manure slurry output needed for a project to be economically feasible.
Once operational, the colony was saving about $250,000 annually on its power bill and $100,000 to truck the manure for land spreading. It also took care of the odor problem, which was a main issue with the colony at the time.
When the project came on line in 2002, power rates in Alberta were heading upward toward an all-time high, driven largely by record natural gas prices. In 2005, natural gas prices peaked and then began a steady decline. At about the same time, the provincial government decided to slow down and phase in the transition to complete power deregulation, reacting to a strong public outcry concerning the high cost of power. Since then, the province has become a fully deregulated energy market.
With power rates coming down and the colony’s need to truck water to the site to maintain the anaerobic digestion process, they decided to decommission the operation after three years. They are now using the digestion vessels for storage and are once again land spreading the manure. Meikle says the technology is still intact, and with a bit of maintenance and updates, the colony could quite easily be in the power generation business again at some future date. From BioGem’s standpoint, it benefited because the Iron Creek project succeeded as a proving ground for the application of this technology to a North American intensive livestock operation. “The technology worked well for us,” says Meikle. “We will make some changes when we build our next plant, but the basic technology as far as the digesters, the engine and electronics, there’s no problem at all.”
The Luxembourg design promoted by Open Energy is a low temperature system, meaning that the temperature within the anaerobic digesters needs to be between 37 and 45 degrees C to maintain a healthy bacteria culture, which is key to the biological process of converting the manure slurry into methane gas, as well as pathogen-free liquids and solids. A high temperature system operates at between 45 and 50 degrees C and produces more gas per liter of waste, but is less forgiving and more unstable as far as maintaining a healthy bacteria culture.
It is a flow-through process, meaning that a raw manure slurry is consistently being added at one end while biogas is being generated from the digesters and transported to fuel the engine that drives the electric generator at the other end. The entire conversion process takes 30 to 35 days for the maximum value of methane gas to be extracted from a liter of manure slurry.
Biogas production begins when the raw manure passes through a pre-processing stage where grinding and mastication occurs to reduce the particle size so that it can be mixed with water and inputted into the system as slurry. It then undergoes secondary grinding before being pumped into the digester. A computer program controls the input rate.
As the biological process occurs, the biogas rises and collects in a large collection bladder above the digester, where it cools, and is then transported to power the engine. The remaining liquid by-product is typically recreation grade, meaning that it can be used for land irrigation, wash water, or can be re-introduced into the biogas production process. The solid by-product is a pathogen-free compost that can be used as an organic fertilizer. Some farmers are also using it as bedding in dairy operations. Open Energy is currently investigating the possible manufacture of pellets from the solid by-product by mixing it with a binder.
BioGem Systems was wound down as a company, as lower energy prices and the slow pace of government support for green power made it hard to build a strong business case to move forward with the venture. However, Meikle and his Open Energy partners now feel re-energized given the current state of public interest and a number of groundbreaking recent government initiatives that they believe are rekindling growth potential in such alternative energy projects as manure conversion to biogas.