Combined Calefaction

A Canadian community merged three biomass plants into one big success story for district heat.
By Luke Geiver | January 25, 2012

Paul Eastman oversees all of Veresen Inc.’s power facilities in Eastern Canada, including the first-ever municipal solid waste (MSW) and woody biomass-fueled system in the country. Prince Edward Island’s (PEI) biomass district heating plant provides heat for more than 125 buildings in the capital city of Charlottetown, and 1.4 MW of power for internal use, as well as sale to the grid. The operation is a great example of why district heating systems fueled by biomass make sense.

Eastman says Veresen acquired the PEI facility in 2007 because it made sense to buy a company with a wide moat around it, literally. PEI also has no threat of alternatives cutting away at its profits, he explains. The facility, which uses a small portion of heating oil, features long-term contracts that generate a steady cash flow, and uses readily available biomass feedstock to solve a somewhat complicated energy problem. “There certainly isn’t the ability to power anything with natural gas there,” Eastman says. 

But even for Eastman, the story of the facility isn’t about a company’s successful realization that Prince Edward Island really did appear to have that large mote around it—in the form of the Gulf of St. Lawrence and the Northumberland Strait, both part of the Atlantic Ocean. For Eastman, and those before him involved in linking three separate biomass-based systems together to form the present day facility, it is about so much more.

Three Become One

Dave Godkin worked in Charlottetown at the University of Prince Edward Island back in the 1980s, when high oil prices and potential landfill issues were on the horizon for the province. Godkin, now the general manager for plant operator PEI Energy Systems, was instrumental in making the current district heating system what it is today. “I started on the ground floor as they were building it up,” he says of his time spent as an energy consultant and maintenance manager at one of the original biomass sites on the University’s campus.

Godkin helped the Province meet its goal of utilizing more biomass created from a then-stable forestry industry, as well as circumventing some of the concerns related to MSW. The MSW plant that came online in 1983 to provide power to a major hospital was the first facility on the island to use MSW for power, and then in 1986, a woody biomass-based district heating system was introduced to the downtown area to serve the Provincial offices and a number of other customers. By 1995, the island had added another biomass heating facility on the campus of the University of Prince Edward Island to serve not only the campus, but other surrounding buildings, as well.

“In the mid-’90s, the province decided it didn’t want to be in the district energy business anymore and went out for expressions of interest for someone to purchase the district heating system,” Godkin says, adding that, perhaps more important, the province was looking for someone to commercialize the system.

As part of the purchase agreement, the province stipulated that any potential buyer would have to further develop the MSW plant, upgrading the site to allow a merger of all three district heating systems into one large system, Godkin said. Robert Doyle, now a principle with FVB Energy Inc., a district heating developer that specializes in biomass utilization, had helped design one of the three biomass facilities. Doyle was certain the idea of upgrading the MSW facility with new biomass boilers on the same location was a great idea.

In 1997, a company called Trigen purchased the three district heating systems and funded the upgrades, which, according to Godkin, happened in a fairly quick timeframe—one year—and included installation of six kilometers (3.7 miles) of underground pipe to connect the systems, new heat recovery equipment, and new air pollution control equipment. Since the upgrades, little has changed at the facility. “One thing that has changed a little bit for us is the type of fuel used,” Godkin says. 
When the main MSW and woody biomass facility first came online in 1997, the biomass feedstock was sawmill residue, but after an operational downturn at the sawmill, the plant needed another feedstock stream, Godkin says. “We moved away from sawmill residue to forest chips from land clearing or residue left over from cutting,” he says. “That is basically where we sit today. That is one of the bonuses of district energy and large biomass facilities: you can switch fuels fairly quickly without a whole lot of trouble.”

The Real Story

There was no question of whether Veresen’s purchase of PEI Energy Systems' district heating plant and infrastructure was a promising endeavor. “It looked profitable, it looked like it would continue to be that way and it looked like there was potential to grow over time,” Eastman says. “I think that is still true.” But, he adds, the concept of district energy is odd and difficult to understand. Doyle agrees with Eastman’s sentiment, adding that the biomass component of district energy needs to be outlined separately, because of its significant advantages.

Doyle and Godkin agree that the benefits of biomass in a district heating system can outweigh the challenges created by linking businesses to residential buildings, and private sector energy budgets to public. They also agree that the PEI story proves that.

Doyle’s research into other systems also makes it difficult to argue with such claims. His team has completed a project to turn sawmill waste into heat for a downtown area of a British Columbia, Canada, city, and is currently working on other projects in British Columbia: one that will use sawmill waste to generate hot water for a central heating system at Prince George; and a wood waste-fired campus and residential heating system, both set to come on line this year. In Alberta, Canada, Doyle is developing a biomass pellet boiler for a water heating system, and is in the process of designing a biomass boiler in the Northwest Territories that could be operational in the summer of next year. “There is a lot of interest (in biomass-based heating applications),” Doyle says. “I think district heating applications are good for biomass.”

Although Doyle’s opinion might seem biased, he cites several compelling reasons biomass makes sense for district heating efforts, and why stories like PEI’s should unfold everywhere.

“One of the challenges for biomass has always been that it’s not as easy as turning on a natural gas boiler,” he says. “It is not as easy as going over to flick a switch.” But, because biomass systems are more complex, combining a woody biomass system with an MSW system, as PEI and Godkin did, makes sense based on the requirements needed to operate an MSW facility, Doyle explains.

“MSW is even more complicated in terms of the combustion process, and a skilled operator who can handle MSW will also be adept at handling woody biomass,” Doyle says. “You have very knowledgeable operators (at an MSW facility), skilled people who on a daily basis are dealing with fuel quality issues, moisture issues, fuel feed issues, all of the things that make running a biomass or MSW system more difficult.”

But if a district heating system isn’t already using MSW for fuel, woody biomass still makes sense, even though running a district energy system presents challenges. Those challenges, however, are related to capital, infrastructure and customers. “It’s not a technical challenge,” Doyle says. The right combination of customers and capital is required to get a project started, he adds, noting that biomass feedstock and conversion technology are rarely issues. Thankfully, the PEI Energy system benefited from government support, Godkin adds.

Doyle’s reasoning for using biomass in a district heating system is also about the profile of the user. While some heating systems operating in pulp mills run at 60 to 90 percent capacity all day every day for 365 days a year, most, like Charlottetown’s, aren’t placed in the same operational conditions. Those systems in a mill don’t have to cycle through huge swings during the day, Doyle explains, putting his point in perspective. “In your house, you get up in the morning and turn the heat up; you go away for the day and you turn the heat down. So your load profile switched dramatically during the day for heating.”

Sound like a problem for commercial and residential buildings that might be considering a biomass-based heating system? Doyle would say no. Although a biomass boiler doesn’t like huge load changes, the biomass-based district heating system benefits from the fact that typically there are enough customers and enough load base to justify full-time operators for at least 12 hours per day. Larger systems also make more sense, he says, as they allow larger stacks with filter systems, all of which help to justify the capital for a larger system.

Add in the sustainability of biomass and the ability to create jobs, or in most places like Charlottetown that at one time relied on the forestry industry, save jobs, and Doyle says biomass-based district energy project development will only increase.

To take part in that development, Godkin has his own advice: “You’ve got to be committed to it. You have to take a long-term view of your energy supply. I think that is one thing they were doing in PEI.”
Although Eastman and his team at Veresen believe they won’t necessarily seek out projects involving biomass in the future, Eastman’s plans for the Charlottetown facility show that his role in the story of Prince Edward Island isn’t simply about his success in finding that moat.

“I think there is a huge opportunity to expand that facility,” he says, based on the possibility to utilize a higher percentage of MSW. “And there should be the economics to support expansion to the point where we could displace all of the oil that we burn at the facility.”

Author: Luke Geiver
Associate Editor, Biomass Power & Thermal
(701) 738-4944