Final Thoughts: Forest fire fuel

Although disturbed forests testify to the extent of nature’s strength, they also prompt the question as to whether forest waste can be transformed into something valuable for society.

In this new study published in the journal Applied Energy, my research investigates the potential amount of biomass from salvage logging of fire-killed stands along with harvesting residues from clearcut to supply pellet plants in Eastern Canada (North Shore Area in the province of Quebec). This region has been particularly chosen given its large amounts of under-exploited biomass, and also because of open ports on the Atlantic, which offer shorter transportation distances to Europe (6,000 km versus 16,000 from Vancouver). Various supply scenarios were optimized to fulfill different pellet plant capacities under various operational, ecological, and economic constraints.

Despite the high spatial and temporal variability of burned area, this study highlights the large quantities of biomass from fire-killed stands available as ecologically sustainable feedstock for pellet production. Between 2002 and 2011, the average annual amount of biomass available from fire-killed stands was estimated up to 750,000 ODT/year (calculated by harvesting the stem only), which is eight times higher than the amount available from harvesting residues (branches only), with around 90,000 ODT/year estimated for the same period.

In our optimized scenarios, we showed that under current market conditions (wood chips fixed at $90/ODT), biomass both from harvest residues and fire-killed stands could fulfill on average between five per cent and 66 per cent of a 50,000 ODT/ year plant. With a wood chip price at $120/ODT, 100 per cent of the production capacity of a 50,000 ODT /year plant and a 100,000 ODT/ year plant could be met. In the same optimist scenario 83 per cent of the production capacity of a 300,000 ODT/ year plant could be met (more scenarios are available in the paper).

Ecological constraints related to the need to protect sensitive sites and prevent recovery operations on them, and operational constraints related to the capacity of the machinery to recover biomass from a given site, have little impact on the supply of biomass from fire-killed stands. However, important regional variations exist in terms of potentials and constraints, which would need to be taken into account when designing bioenergy industrial networks.

Pellet production based on feedstock from naturally (and then randomly) disturbed stands could make supply chains more risky in terms of long term stability and logistics, compared with intensive silviculture, for instance. One option when dealing with uncertainty and risks for potential supply breakdowns is to develop flexible integrated supply chains that could rely on multiple feedstock sources, where traditional forest products and waste streams are integrated to optimize biomass flow and uses.

While climate change is predicted to increase the occurrence of natural disturbances in the boreal forest biomes and the resulting standing deadwood, the Intergovernmental Panel on Climate Change (IPCC) stated recently that this type of feedstock was seen as a promising resource for the deployment of bioenergy at the global scale over the next 50 years.

As European countries are becoming more severe regarding the ecological sustainability of biomass harvesting, Canada has strong opportunities in optimizing the supply chains of this under-utilized feedstock and becoming a leader in the green economy.

The information presented is from Sustainable biomass supply chains from salvage logging of fire-killed stands: A case study for wood pellet production in Eastern Canada, which originally appeared in the journal Applied Energy. The research was a collaborative effort between researchers at Natural Resources Canada and the FORAC research consortium at Laval University. For more information, email Nicolas.Mansuy@rncan-nrcan.gc.ca