How biogas can fit with a sustainable agriculture strategy

The landscape for renewable natural gas (RNG) production on Ontario farms is getting bigger, but the provincial and federal governments must stop thinking of the fuel in the same way as they do for natural gas derived from fossil fuels.

That was the take-home message from a group of panelists representing the agriculture sector at the Value of Biogas East conference in Toronto April 24-26, hosted by the Canadian Biogas Association.

Why it matters: On-farm biogas production can help reduce greenhouse gas emissions, help farmers manage nutrients and provide a renewable source of energy.

The panel focused on ways agriculture can contribute to RNG via the production of biogas from anaerobic digesters.

“Farmers are on the frontlines of changing climate and farmers are part of the solution,” said panel moderator Kate Bigney, deputy director at Agriculture and Agri-Food Canada and a member of AAFC’s bioeconomy policy group.

She said farmers are inherently interested in resilience and “by necessity have to adapt to climate change.”

Why biogas?

AAFC sees biogas produced on-farm as beneficial to farmer in terms of reducing input costs and managing nutrients, and also for greening Canada’s economy, which is the impetus of Canada’s Sustainable Agriculture Strategy, she said.

According to the Canadian Biogas Association, capturing and utilizing biogas from the anaerobic digestion of feedstocks such as manure, crop residues and food waste “is a powerful tool” for reducing greenhouse gas emissions.

This is achieved in two ways: the biogas is a source of renewable energy that can replace fossil fuels; and it captures methane emissions that would otherwise be released to the atmosphere. Biogas can be used to generate electricity or on-site heat and is interchangeable with natural gas for pipeline injection and transportation uses.

Beef farmer and panelist Carl Frook installed a 750 kilowatt biogas plant from Bio-En Power Inc. on his farm near Hanover in 2012, known as Marl Creek Renewables, under the feed-in tariff program. The Frook family feed 3,000 cattle and crop about 1,200 acres.

The biogas plant has been operating for more than 10 years and generates about 18 megawatts of electricity per day. It is used to power the farm and the excess is sold to the energy grid, Frook said.

The family was motivated to build a biogas plant after the Walkerton E.coli water contamination crisis in spring 2000. Heavy rainfall washed bacteria from cattle manure spread on fields into the aquifer of a nearby well. Walkerton public utility workers failed to treat the water properly, resulting in contaminated drinking water that sickened more than 2,000 people and killed seven.

“Being a beef farmer after the crisis and hauling manure down a road to a farm to spread nutrients to grow a crop and make a living, we felt like criminals,” he said. “It was not a good time.”

Frook looked for safer and more sustainable ways to manage manure from the farm, which led him to biogas. Digesting manure anaerobically to produce biogas removes pathogens and has the added benefit of destroying weed seeds. It also provides a ready-made fertilizer, he said.

“We haven’t bought commercial fertilizer in over 10 years.”

Frook admits to “not really having a clue” about building a biogas plant, but now thinks every farm should have one for the treatment of manure.

“It changes the way animals are cared for in the livestock industry. It changes the way you can produce crops sustainably. It’s nutrient management and the full circle of nutrients and organics and manure coming back to a farm and then applying it to grow a crop. It’s a pretty neat circle.”

Fellow panelist Rob McKinlay echoed Frook’s thoughts on how treating manure leads to greater nutrient management and sustainability on his farm.

McKinlay and his wife Rachel own Harcolm Farm in Beachville, where they milk 84 Jersey cows and “have just enough land to support the feed for those cattle.”

In 2017, they installed what McKinlay believes to be the province’s only mini-biodigester, using the MicroFIT program. Harcolm doesn’t sell electricity back to the grid because the 20 kW mini biodigester doesn’t produce enough excess electricity, but it has reduced the farm’s electricity bill by nearly 70 per cent.

Mini-digesters cost less and are more popular in Europe (Harcolm’s was imported from Belgium), and designed to handle only manure as a feedstock. Harcolm’s unit separates the digested manure into solid and liquid forms. The solids are used for bedding and the liquid is used as fertilizer.

This separation “eliminates trucking of sand or shavings into the farm for bedding,” he said. “In terms of nutrient management, I think what happened at our place was there was a bit of a mindset shift in terms of how we utilize our nutrients.”

McKinlay said they’ve started to introduce more cover crops in recent years, and they can be harvested in spring for cattle forage. This allows the farm to grow two crops on land that it wouldn’t have otherwise.

“In terms of how we use our nutrients as a small operation, we’re doing things like multiple applications [of liquid digestate] during the growing season, which eliminates the need for commercial fertilizer.”

He said opportunities to achieve greater sustainability from biogas production on the farm aren’t size-dependent.

“In terms of scale and scope, my farm and Carl’s farm are quite different, but the benefits that we see are the same.”

Expansion challenges

Given the sustainability benefits and energy savings of on-farm biogas production, panelists were asked what they thought was hindering more rapid biogas development in the agriculture sector.

Panelist Ian Nokes, a policy analyst with the Ontario Federation of Agriculture, believes there has been too much focus on electrification of biogas. In Ontario, he said most biogas is used to generate electricity and this was partially due to FIT contracts.

“Ontario has been kind of hesitant to look at incenting renewable natural gas,” he said, and there haven’t been incentives to use biogas for direct heat or combustion. Regulations for pipeline transport of renewable natural gas are also more stringent than for connection to the electric system, he noted.

“I think it’s pretty clear that the federal and provincial governments see more electric generation in our load systems and they don’t see room for fuel, even clean fuel generation,” said Nokes.

“I think one of the challenges I see is making sure policy and decision makers understand that, yeah, we’re going to have a more electrified and more decarbonized energy system. But the challenges and opportunities in rural areas, areas outside of cities and urban centres are different.

“And we are going to need incentives, we’re still going to have all passive vehicles and transportation systems to be electric like they want … and we still need grain drying, we still need tractors, we still need these fuels.

“So, the challenge is going to be making sure they understand that in rural areas, biogas and renewable natural gas are going to be solutions for us.”

Geography and infrastructure are other challenges. Frook said when he was ready to install the biogas plant on his farm, it required three-phase hydro, which wasn’t available. He had to foot the bill to install a 3.5-kilometre hydro line.

Nokes believes the cost to implement biogas plants on farms is also a challenge. Co-digestion with feedstocks from off the farm will be needed (such as bakery waste, for example) to make it cost-effective. But, he said, “it could be a gamble every time they get a truck load in” because the quality of other feedstocks is unknown and could affect the anaerobic digestion process.

Without funding incentives, he expects competition for agricultural feedstocks among farm-based biogas plants and municipal ones.

McKinlay said collaboration between multiple government departments is needed.

“We need collaboration from energy, environment, agriculture, and then also across jurisdictions in terms of municipalities, and provincial energy policy.”

He said all these departments aren’t that far apart in terms of shared vision, and the agriculture sector should talk with them about its role and what it could do to help align their visions.

As for incentives, he doesn’t think another FIT program is the answer. He’d like a provincial energy policy that allows producers to monetize production forever.

“A one-time incentive on capital is just kind of dirty. It’s nicer to be able to make that money forever, rather than getting a big fat cheque at the front end, to make up for inefficiencies in the system elsewhere.”