Bioenergy from biomass

Bioenergy is energy produced from renewable, biological sources such as biomass. Biomass is plant material that can be turned into fuel (also known as biofuel when it is made from biological material) to supply heat and electricity.

Bioenergy can be obtained from many forms of biofuels. These include liquid biofuels used to run motor vehicles, and forest wood residue used to run pulp mill and other industrial operations.

Biomass sources

Forest biomass used to produce bioenergy comes from many sources:

  • trees that are of harvestable age but are not suitable for lumber
  • material from stand thinning
  • harvest residues
  • trees killed by disturbances such as fire, diseases or insects
  • trees from plantations grown specifically to provide biomass for conversion to bioenergy

By-products of industrial forest processes provide another source of biomass for bioenergy use. Among those by-products are wood residues (such as sawdust, bark and chips) from harvesting and milling operations, and pulp residues (such as the lignin-rich “black liquors”) left over from the pulping process.

For biomass to be directed effectively into energy production, the biomass must be supplied at a competitive cost and its use for this purpose must cause minimal environmental impact. The quality of the biomass must also be optimal for energy conversion and end use.

To meet these criteria, special harvesting technologies and post-harvest treatments have been developed. As well, Canadian Forest Service (CFS) research in this area continues to focus on:

  • identifying more sources of both existing and new biomass;
  • developing efficient methods of growing, harvesting and collecting biomass and of transporting it to sites where it will be converted into biofuel; and
  • demonstrating the sustainability of increased biomass supply.

Forest biomass “energy plantations”

Plantations established specifically to “grow biomass” for bioenergy production offer several benefits over natural forest stands as sources of biomass for the same purpose:

Biomass plantation

Biomass plantation

  • Trees grown in natural forests usually take 40 to 100 years to mature. Those grown in use-specific plantations—that is, to produce biomass suitable for converting to bioenergy—usually grow in 3 to 15 years.
  • Having the flexibility to grow biomass in plantations close to where the bioenergy will be put to use offers substantial supply cost reductions.
  • Surplus or marginal land not economically or biologically productive for agriculture may be well suited for forest biomass crops, providing landowners and farmers with an additional cash crop.

Improvements to cultivation systems are increasing the biomass productivity of these plantations of “dedicated energy crops.” Today, for example, improved fertilization, irrigation and pest control are enabling Canadian plantations to produce 10–15 oven-dry tonnes of biomass per hectare annually.

Silver maple and several varieties of fast-growing poplars, willows and alder have been tested for their suitability in increasing yields in forest biomass plantations in Canada. Successes include:

  • A program in eastern Ontario which demonstrated that hybrid poplars from genetically improved stock could be established and grown to produce biomass on a sustainable basis.
  • A project in Newfoundland in which willows from Europe yielded 8–12 oven-dry tonnes per hectare a year. Spectacular growth of individual willow clones was also demonstrated on nursery plots using intensive cultivation.
  • Trials at Montreal’s Botanical Gardens which demonstrated effective establishment and maintenance techniques for improving the growth and yield of several short-rotation species, such as poplar and willow. Additional work examined the use of dried municipal sludge as an environmentally safe form of fertilizer.

For the operational harvesting of biomass from energy plantations, modified agricultural equipment and existing European machinery have worked most effectively.

Canada’s work with IEA Bioenergy

Biomass energy plant

Biomass energy plant

Canada is one of 17 countries that participate in the research activities of International Energy Agency (IEA) Bioenergy, an organization whose focus is improving the cooperation and sharing of information between countries with national programs of bioenergy research, development and deployment.

Canada contributes knowledge, expertise and funds to IEA Bioenergy and, in return, has access to research results and scientific exchanges such as clonal material from other member countries. As well, IEA Bioenergy has contributed to research in Canada. For example, information from IEA has assisted with projects studying the sustainability of forest residues for bioenergy production, as well as the potential effects on land use of changing over to enhanced bioenergy production.

Canada is involved in nine bioenergy tasks, including IEA Bioenergy Task 43, Biomass Feedstocks for Energy Markets. The goal of Task 43 is to promote sound bioenergy development through well-informed decisions by business, government and other sectors. The aim of IEA Bioenergy participants in this task is to support decision-making by providing timely and topical analyses, syntheses and general data on all fields related to biomass feedstock, including biomass markets and the socioeconomic and environmental consequences of feedstock production.

Continuing research on bioenergy

The contribution of forest biomass to Canada’s energy supply has increased from 3 to 4% in the 1970s to 5–6% today. Changes in pulp and paper technology have resulted in most of this increase.

Much is being learned about forest biomass and bioenergy technologies through CFS research. The Forest Biomass Inventory, the FORCYTE model, whole-tree harvesting and nutrient cycling, the Carbon Budget Model, and species, clones and production technologies for energy plantations are all areas where work is underway.

More research is planned as environmental and economic needs continue to make forest-based bioenergy an increasingly attractive energy alternative for Canada.