This article was published by the Canada Energy Regulator on May 17, 2023.
Canada has a well-established bioenergy sector, contributing to over 6 per cent(1) of total primary energy in 2021. Canada’s bioenergy sector has been steadily growing in the past two decades with significant expansions expected in the near future.(2)(3) Considered a low carbon form of energy, bioenergy is expected to contribute to net-zero efforts both in Canada and globally.
Total primary energy available to Canada from biomass is around 1,800 petajoules (PJ) per year. When converted to end-use products, only some of that primary energy becomes end-use energy (some energy is lost during processing). For simplicity, if it is assumed primary energy contained within all biomass feedstocks is converted to end-use energy with an efficiency of 35 per cent, then the total national end-use energy from biomass feedstocks would be around 630 PJ per year. That represents enough energy, including heating and electricity, for over 7 million households in Canada.(4)
Figure 1: Annual primary energy supply by different biomass feedstocks by province or territory
Different kinds of bioenergy have different energy potentials
Each biomass feedstock has its own energy density. There are two ways to measure this. Primary energy is the energy contained within raw biomass before converting it to end-use products such as biofuels and electricity. End-use energy is the energy contained within the end-use products. Sometimes, the raw product is also the end-use product (such as firewood).
Not all feedstocks are suitable to produce all types of bioenergy. For example, firewood is preferred for electricity generation or heating, whereas municipal solid waste is mainly used to make biofuels like biogas and renewable natural gas.
Where does biomass for bioenergy come from?
Bioenergy is made primarily with biomass feedstocks. Biomass is organic material from plants or animals, which is either burned to create energy, or converted to different products before burning. Bioenergy can be in the form of biofuels like ethanol, biodiesel, biogas, and renewable natural gas; it is also used to generate electricity and produce hydrogen.
Bioenergy feedstocks are diverse, ranging from livestock manure to trees. These feedstocks can be purpose-grown, like plants and trees specifically grown to become bioenergy, or residue(7) from another activity. They are categorized below by origin:
- Urban waste: waste from residents, industries (like pulp and paper), institutions, commercial activities, and waste from landfills and sewage.
- Livestock residue: residue from livestock farming and processing, including animal manure, animal oils, and animal fats.
- Purpose-grown energy crops: crops grown for energy, including corn, wheat, willow, canola, switchgrass, miscanthus, hybrid poplar, and more.
- Crop residue: plant remains after crops are harvested and processed.
- Forestry: mainly wood produced as firewood and fuelwood,(8) and includes wood produced as a result of sustainable forestry practices, such as wildfire mitigation and pest control.
- Forestry residue: unused materials from trees after harvesting and processing for lumber or other non-energy uses. Includes treetops, tree branches, and forest product manufacturing residues such as sawdust from sawmills.
Figure 2: Different types of biomass feedstocks
Bioenergy can be low carbon when managed properly
Plants capture and store carbon dioxide (CO2) during their lifespan, and when they die, they slowly release that CO2 back into the atmosphere. This sequence is part of the short carbon cycle.(9) Burning biomass, either directly or as biofuels, releases the CO2 originally captured and stored in plants that would otherwise naturally release and is considered carbon-neutral.(10) Bioenergy does release small amounts of other greenhouse gases (GHGs) like methane, but is still considered low-carbon when well-managed. When paired with carbon capture and storage technology, or Bioenergy Carbon Capture and Storage (BECCS), bioenergy can become a net-negative emitting renewable energy source.(11)