Climate change mitigation potential of local use of harvest residues for bioenergy in Canada

Abstract

We estimate the mitigation potential of local use of bioenergy from harvest residues for the 2.3 × 106 km2 (232 Mha) of Canada's managed forests from 2017 to 2050 using three models: Carbon Budget Model of the Canadian Forest Sector (CBM‐CFS3), a harvested wood products (HWP) model that estimates bioenergy emissions, and a model of emission substitution benefits from the use of bioenergy. We compare the use of harvest residues for local heat and electricity production relative to a base case scenario and estimate the climate change mitigation potential at the forest management unit level. Results demonstrate large differences between and within provinces and territories across Canada. We identify regions with increasing benefits to the atmosphere for many decades into the future and regions where no net benefit would occur over the 33‐year study horizon. The cumulative mitigation potential for regions with positive mitigation was predicted to be 429 Tg CO2e in 2050, with 7.1 TgC yr −1 of harvest residues producing bioenergy that met 3.1% of the heat demand and 2.9% of the electricity demand for 32.1 million people living within these regions. Our results show that regions with positive mitigation produced bioenergy, mainly from combined heat and power facilities, with emissions intensities that ranged from roughly 90 to 500 kg CO2e MWh−1. Roughly 40% of the total captured harvest residue was associated with regions that were predicted to have a negative cumulative mitigation potential in 2050 of −152 Tg CO2e. We conclude that the capture of harvest residues to produce local bioenergy can reduce GHG emissions in populated regions where bioenergy, mainly from combined heat and power facilities, offsets fossil fuel sources (fuel oil, coal and petcoke, and natural gas).

Climate, economic, and environmental impacts of producing wood for bioenergy

“…The assessment should compare the emissions associated with the proposed activity against the emissions associated with the baseline. Life-cycle analysis using appropriate emissions or displacement factors, and a landscape-specific assessment of transportation, is a recommended approach (Smyth et al 2017).…”

“…Recent studies show that with full accounting, the GHG effects are conditional upon many factors such as source of biomass (i.e. wood residues or whole trees and their fate if not used for bioenergy), time horizon of analysis, and assumptions about what would happen if biofuel production were not increased (Miner et al 2014, Smyth et al 2017, Ter-Mikaelian et al 2015, Booth 2018.…”

Atmospheric change as a driver of change in the Canadian boreal zone1

“…Resourcedependent economic and industrial sectors (e.g., forestry, energy production, mining, agriculture, fisheries) in the boreal have represented a relatively minor portion of the total income and employment in Canada (Patriquin et al 2007(Patriquin et al , 2009. The projected effects of atmospheric change have the potential to influence future contributions of the boreal to the economy of Canada (Kovacs and Thistlethwaite 2014;Lemmen et al 2014;Smyth et al 2017a). Residential, industrial, transportation, and public infrastructure (e.g., water treatment facilities), particularly in the northern boreal, are likely to face higher risk in a warming climate, where they depend on low, sub-zero temperatures of the underlying permafrost or ice (e.g., of winter roads) to maintain structural integrity (Prowse et al 2009a).…”

A Participatory Approach to Evaluating Strategies for Forest Carbon Mitigation in British Columbia

“…Participants insisted that bioenergy should only be used to replace emission-intensive fossil fuels such as coal and diesel, but not clean energy (for example, see [57]). Many groups also discussed the fact that the strategy would be most effective in the context of off-the-grid remote communities that are using emission-intensive energy sources like diesel (discussed in [58]). Although it was not analysed or presented to participants, many wished to stress that standing live trees should not be harvested to produce bioenergy.…”