2021-04-28
Environmentalists are giving a cautious thumbs-up to the concept of heating entire towns by burning truckloads of pulpwood and sawmill scraps that once would have been gobbled up by Pictou County's Northern Pulp mill.
The concept is one that Mahone Bay bio-energy consultant Jamie Stephen has been touting, and communities around the province are quietly working on.
He says notions that burning biomass is inefficient, dirty and leads to clear cutting are the biggest hurdle for environmentalists.
Nova Scotia Power's Point Tupper in Cape Breton and Brooklyn Energy on the South Shore, owned by the electric utility's parent Emera Inc., burn biomass for electricity. The process counts as green energy, despite a woefully poor efficiency rate of between 30 per cent and 34 per cent.
Generating heat from biomass, as Stephen is proposing, has significantly higher efficiency, at upwards of 85 per cent to 90 per cent, as the technology for bio-energy, like telephones, has grown by leaps and bounds.
Many Nova Scotians might not realize that when they turn on their new, energy-efficient heat pumps or plug in their electric vehicles that they're powered roughly 50 per cent by coal. Nova Scotia Power is in the midst of a many-decade pursuit to wean itself off the dirty fossil fuel. New Premier Iain Rankin is pushing that target 10 years closer to 2030.
The tighter deadline for the transformation is bound to be costly for customers, however. And even when Muskrat Falls hydroelectric power is fully flowing from Newfoundland and Labrador, fossil fuels will still account for the majority of power generation here.
Unlike fossil fuels, biomass is touted as a renewable, carbon-neutral resource. The logic is, while burning biomass releases carbon dioxide, a greenhouse gas, the trees and plants that are the source of biomass capture greenhouse gases through photosynthesis while they grow.
Environmentalists, including Ecology Action Centre senior wilderness coordinator Raymond Plourde, scoff at the notion.
"Europe has been subsidizing this massively because it's considered green and renewable," says Plourde. "It's the critical climate accounting error. To count the burning of trees, chips and pellets as carbon neutral with zero greenhouse gasses is crazy."
That makes him an outspoken critic of the inefficient Point Tupper and Brooklyn biomass plants. But Plourde says he gives "a cautious thumbs up" to energy efficient district energy systems that would be fueled by burning by-products from sawmills.
"What's the best thing you could do with these leftovers? Frankly, sweep them up and truck them back to the woods to feed our otherwise very impoverished soils," he says. "But that's impractical. Selling into a biomass market that was focused exclusively on supplying district heating plants in municipalities throughout the province, to a certain limit, makes sense."
He isn't in favour of pulpwood once destined for the province's mills being repurposed at industrial levels for biomass boilers and wood pellets. The limit should be to sawmill residue and some silviculture thinning from the forest "and hope on Boy Scout honour they're not grinding up anything else." To help with forestry sustainability, the province should have a "Nova Scotia first" policy and not export wood pellets and chips to feed Europe's insatiable appetite, he adds
Filling the Northern Pulp gap
Stephen moved to Mahone Bay from Ontario last year specifically to champion conversions to biomass district heating systems post-Northern Pulp. He argues that sustainable forestry, as spelled out in 2018's independent Lahey report on the province's forestry practices, requires a market for pulpwood. "This is small diameter, low value, low quality standing timber," he says. "A lot of timber cannot be milled into lumber. Historically, that timber went to produce pulp and paper. However, with the closure of both Bowater Mersey and Northern Pulp, there is insufficient demand from the pulp and paper sector."
Northern Pulp, which was shut in early 2020 after then Premier Stephen McNeil refused to allow the mill to continue dumping effluent into Boat Harbour, is trying to make a comeback. It's unclear whether the company's new proposal will continue to seek approval for a plan to pump treated wastewater into the Northumberland Strait. With the resumption of the mill, pulp products would be shipped out of the province and new environmental consequences could arise.
Burning biomass for heat might be the safer bet for a viable, sustainable forestry industry.
Either way, a buyer for low-grade wood is needed. Without one, high-grading and clear cutting are the only two timber harvest options. "High-grading, which is the removal of only sawlogs, is a completely unsustainable forestry practice and is not permitted on Crown land. It decreases the genetic quality of the forest because you a removing all the best trees," says Stephen. "Clear cutting and leaving trees in the forest to rot is a complete waste of a resource."
Winning approval for district energy systems and building them could take a few years. Stephen says steps could be taken sooner to improve efficiency with biomass. Brooklyn Energy largely has been without a heat customer since the shutdown of Bowater Mersey. "A use of heat, which is currently being wasted, would dramatically increase the efficiency of the Brooklyn plant without any additional wood fibre consumption," says Stephen. He points to Varberg, Sweden, which ran an 18 km transmission line from the pulp mill to the town, as an example.
Making biomass at Brooklyn Energy more viable could be a boon to Greenfield-based Freeman Lumber, the largest sawmill west of Halifax. The multi-generational business warned last year it might go under after losing Northern Pulp as a buyer for its wood chips.
Nova Scotia also has several district energy systems that could be converted to biomass in less than a year. Candidates are the Canadian Forces Bases in Halifax and Greenwood and university campuses, including Dalhousie, Acadia and StFX. Dal's Truro campus is already heated with a biomass plant. Meanwhile, the Provincial Court and NSCC campus in Bridgewater are among six individual public buildings in the province the government of Nova Scotia has committed to converting.
Stephen says biomass is a good companion to solar panels and wind turbines. While a growing part of Nova Scotia's green footprint, the two renewable sources lack the capacity and storage capabilities to meet all of province's energy needs. Bio-energy is already big in the Maritimes. With many homes heated by pellet and wood stoves, it accounts for 73 per cent of all renewable energy in the region, putting it well ahead of solar and wind.
"There are a lot of campaigns that are electrify everything and add wind and solar and batteries and that's the only solution," says Stephen. "If you actually step back and look at the numbers, we simply will not reach our green-house goals doing that. You can't de-carbonize using electricity if you have a high carbon grid."
Nova Scotia can reach its climate-change goals by burning forestry industry by-products in individual wood pellet boilers and district energy systems, he says. "I moved here specifically because I know this is the approach that will work."
Janet Whitman is a contributing editor and staff reporter with Advocate Media.