Features Anaerobic Digestion Applications Beef Business/Policy Energy Energy Production Profiles
Fact over fiction

A total of $7.1 million was spent to build this PlanET Biogas designed, biogas-fueled, renewable power plant on the Perry farm near Chin, Alberta.  Contributed photo.

It has a futuristic feel to it – two domed anaerobic digester tanks converting feedlot manure and potatoes to biogas and organic fertilizer. Add to that the use of solar power, geothermal power, and composting of cattle manure for use as organic fertilizer and the picture is complete.

But southern Alberta farmers Chris and Harold Perry are more interested in science fact than science fiction and take sustainable farm practices very seriously. Their 20/20 vision is to reduce farm inputs such as water, fuel, electricity and synthetic fertilizer by 20 percent, while increasing net yields by 20 percent. They began to implement that vision in 2011 and the commissioning of their anaerobic digesters is a major piece of the puzzle.

In November, they commissioned a $7.1 million anaerobic digester installation on their farm near Chin, Alberta, that will continuously generate biogas as fuel to produce about 630 kilowatts (kWs) of green power. The two digesters will process about 25,000 tonnes of organic waste annually, which will include at least 13,000 tonnes of open-pen feedlot manure.

The production of renewable power from biogas and diverting manure from the nearby KCL Cattle Company and Kasko Cattle Company feedlots will reduce greenhouse gas (GHG) emissions by more than 10,000 tonnes of carbon dioxide per year.

The anaerobic digester system and renewable power facility is owned by a company called GrowTEC Ltd., which is a division of Perry Produce Ltd. Chris Perry is the company’s co-founder, president and chief executive officer (CEO). The name GrowTEC is an acronym for Grow the Energy Circle Ltd.

The Perry family has a history of innovation and stewardship that spans four generations. Today, they operate a diverse farm comprising 4000 acres of irrigated land producing potatoes, sunflowers, green peas, seed canola and a range of cereals for clients such as Frito Lay, McCain Foods, Lucerne Foods, Hytech Production, and Spitz.

“The Perry’s are very progressive farmers,” says Seth Clark, GrowTEC’s biogas facility production manager. “They really see themselves as stewards of their land. For instance, they were composting manure for quite some time prior to even considering the anaerobic digester just as a way to reduce the amount of synthetic fertilizers they needed for their land.”

The manure used in the composting program will not be disrupted by redirecting that manure to the anaerobic digesters. That operation will continue as before. In recent years, the Perry’s have been manufacturing about 7,500 tonnes of compost from raw manure gathered from area feedlots.

“Here in Southern Alberta, we have a number of feedlots that are manure rich and land poor,” says Clark. “There’s lots of manure out there, and in some cases, there is more manure than the producers can actually apply to their land base. So the project is a win-win for both of us, because we are getting the manure for our digesters from operations that had an overabundance of manure already.”

A major supporter of the GrowTEC renewable energy project was Alberta’s Climate Change and Emissions Management Corporation (CCEMC), which provided over $3.5 million toward the project. Clark says the project would not have been economically feasible without CCEMC’s support. CCEMC is an independent organization created by the Alberta government to channel funds collected from large greenhouse gas emitters toward projects that will help the province reach its GHG emission
reduction targets.

“With current energy prices and market the way it is for electricity in this province, it is very difficult to justify putting a project like this together, purely on the economics,” says Clark.

As part of GrowTEC’s license to operate with the Alberta government, at least 50 percent of the raw feedstock fed into the digester must be feedlot manure, and Clark says at the present time, it is much higher than that.

In addition to the production of renewable power from biogas, the Perry operation is also generating 105 kWs of geothermal power for use in both cooling and heating of their potato storage operation, and 20 kWs of solar power.

The food companies the Perry’s supply have very high quality standards and previously, all potatoes that didn’t make the grade were sent to area feedlots for animal feed or spread back on the land, which involved a fair amount of trucking and transportation.

“Potatoes are a very good feedstock for an anaerobic digester, so it got them thinking about how they could utilize this waste material and add some value to it,” says Clark.

Originally, the plan was to only use potatoes as the digester feedstock, but it was necessary to include manure for the active microbes present in it. Capturing the biogas from digesting these two waste streams will reduce transportation costs and create value added products – biogas for fuel to produce renewable power and high nutrient organic fertilizer.

Clark adds that the Perry’s were interested in taking advantage of both the high nutrient liquid and solid byproduct streams from the digester – two advantages being that the digestate comes out essentially weed and pathogen free.

“Digested manure is actually better for land application than raw product and once you have digested the potato material, any hazards that may have been associated with it, such as diseases and microbes, you have also destroyed those,” says Clark. “So the output is very good, high quality, nutrient-rich fertilizer.” They have included a pasteurization option at the outfeed of the digesters to further ensure that there is no possible transfer of microbes from the feedstock to the digestate before it is land applied. It is pasteurized at 70 degrees Celsius for one hour once it leaves the digesters.

The power generated by their biogas energy system is currently sold to the electricity market in Alberta through the Alberta Electric System Operator (AESO) at market prices. However, down the road, GrowTEC would like to sell the power directly to an industrial user. Chris Perry says that the goal is for the anaerobic digestion system to produce enough income from the sale of renewable power so that the farm operation is essentially, “off the grid.”

GrowTEC contracted a biogas system marketer headquartered in Germany called PlanET Biogas Solutions to build the entire biogas and renewable power system.

“The reason we went with PlanET Biogas as our supplier is that they provide a turnkey operation for biogas. So essentially, you tell them what feedstock you will be using, what your volumes are, what you want for an output, and they will design a system around those parameters,” says Clark. They offer the construction, installation, training, and ongoing support for that system.

PlanET Biogas Solutions is the same company that built Canada’s largest anaerobic digester in nearby Lethbridge last year. It has been actively involved in marketing its technology in North America for a number of years.

The open-pen, bed pack, feedlot manure delivered to the digester site is deposited on a concrete pad.

GrowTEC uses an automated, pre-programmed feeding system to add the required amount of raw material to meet their biogas production target. The raw material is fed once per hour into one of two 2100 cubic metre anaerobic digestion tanks.

PlanET Biogas Solutions worked with MPE Engineering on the project, with Jenbacher being the supplier of the dual-fuel engine that burns the biogas to generate power. Börger supplied the digestate separator, which separates the liquid and solid byproduct streams. The liquid stream is piped to a retention pond, which has enough holding capacity from an entire year of digester production, for eventual land application as fertilizer. The solid material is stockpiled in a bin till land applied.

The temperature within the digester is maintained at 35 to 40 degrees Celsius, with the raw material retained in the tanks for 30 days. Heat generated by the Jenbacher dual-fuel, combined heat and power (CHP) engine is used to heat liquid in a heat exchanger. The hot liquid is then pumped through piping in the walls and floors of the digester tanks to maintain a constant temperature, which is a challenge given that temperatures in the Chin area can sometimes drop to as low as minus 40 Celsius in winter. The engine is capable of burning either biogas or
natural gas.

As to the recipe of raw material, PlanET Biogas provided biological support to GrowTEC to make this determination by analyzing their feedstocks. The blend can be adjusted depending on gas production and quality data, and samples are sent to PlanET Biogas on a regular basis to monitor biology and
bacterial content.

Construction began in August 2013, with completion about one year later. The facility was fully operation in late November 2014. 

 Feedlot manure supplier describes GrowTEC effort as win-win
Cattlemen by nature are cautious when it comes to new ideas about what they know works. That’s because for years they have been subjected to all sorts of products and methods that have promised to grow hair or double their bank accounts.

So it comes as no surprise that Les Wall, KCL Cattle Company owner, is cautiously optimistic about the chances of the GrowTEC renewable power installation working as advertised, although he strongly supports the overall concept. KCL Cattle, located near the Alberta town of Coaldale is a major supplier of raw manure to the installation that features two anaerobic digesters that produce biogas and high nutrient organic fertilizer from the manure.

“I think it’s a win-win for both parties,” says Wall. “It makes you feel good to promote some green energy, they are making good use of our manure, and they are generating energy which helps to run their farms while they sell the excess. I’m pretty happy to be a partner with them. They are good people, and I am pretty excited to see where it will all grow.”

KCL Cattle manages two open-pen feedlots. The one where the manure for the digester is collected holds 7,000 head. It generates between 15,000 and 20,000 tonnes of manure annually, which has traditionally been spread on the three quarters of land owned by the cattle operation and on neighboring farms.

At the present time, the feedlot has stockpiled some manure for GrowTEC’s use as it commissions its two anaerobic digesters. Wall says he’d like to watch it perform for at least six months before giving it the full thumbs up. In future, rather than stockpiling, they hope to clean their pens on a regular basis and deliver the raw manure to the digesters for processing. That concept appeals to him because their pens will be cleaned on a regular basis rather than the pressure of doing it all within a couple months in fall in advance of land application.

“That yard there is not land rich, so it is always good to have another avenue to make better use of your manure, because obviously we can’t use all of it on our land,” he says. Not all the manure that the feedlot generates will be sent to the GrowTEC installation. He expects that some will still be land applied.

One of their main challenges as a raw manure supplier to the digesters is to provide as clean material as possible, with a minimal amount of clay. Wall says that is a challenge, especially in wet years, but they are making a very concerted effort to respond to GrowTEC’s needs.

At the present time, KCL Cattle is not compensated for its manure but the plan is to pay them at least to truck the manure to the site, and perhaps at some future time, they may be compensated per tonne delivered.

“I’m willing to work with them to get started, as long as it doesn’t incur me a lot of extra costs to get it out of my pen,” says Wall. “If I’m covered for that and a little a little bit for trucking, I’m pretty happy for now.”