Wood pellets

Description

Wood pellets are biofuels made from compressed wood fibre.

In British Columbia (BC), wood pellets are made primarily from the residuals left over from the sawmilling process when logs are converted into lumber and other high-value wood products. Increasingly, harvesting residuals in the forest and low-quality logs once left as waste are also a source of raw material for wood pellets. By making wood pellets from fibre that was once burned or left behind, the wood pellet sector is reducing waste and turning that debris into valuable, low carbon biofuel.

How are wood pellets made?

To create wood pellets, producers remove moisture from incoming wood fibre, grind the fibre into dust, and compress the dust into small cylinders—pellets—typically with a 6 or 8 mm diameter, and a length of up to 40 mm. Heat is applied in this process which causes lignin—a natural polymer found in wood—to act as a glue to hold the compressed particles together. The result is a dry, highly compressed and high energy-value product that can be easily handled and transported efficiently over very long distances.

An efficient sustainable source of energy

Wood pellets are used in both domestic and industrial applications. Many people in colder climates worldwide use wood pellet boilers or stoves to heat their homes. Today’s modern boilers are so well automated that they need no human operator or maintenance beyond loading a winter season worth of pellets, pressing a button to start the system and removing the ash six months later. Stoves are more common in North America. Pellets are simply fed by hand into the stove’s hopper and continuously burned to create an efficient, even heat source. Particulate emissions from modern pellet heating equipment are similar, and in some cases lower, than conventional fossil fuel boilers and furnaces. For industrial electricity generation, wood pellets are used as a low-carbon alternative in place of coal. Pellets are ground back to dust, the dust is combined with air, and the resulting mixture is fed continuously to a flame which creates steam to generate electricity.

Are wood pellets a sustainable, low carbon source of energy?

Wood pellets are recognized by scientists and global agencies as a biofuel that offers climate benefits as compared to fossil fuels. The United Nations Intergovernmental Panel on Climate Change (IPCC), the world’s leading authority on climate change, has recognized the significant greenhouse gas mitigation potential of biomass— compared to the fossil energy baseline—provided that it is developed sustainably and used efficiently.

BC’s forests are some of the most resilient and sustainably managed in the world—subject to stringent environmental regulation, careful management and extensive third-party certification.

How are wood pellets sourced?

The pellet industry sources an estimated 85% of its fibre from the by-products of the sawmills and allied industries. A new study confirms that wood pellets in British Columbia are sourced entirely from sawmill and harvest residuals or from low-quality logs and bush grind that would otherwise be rejected by other industries.

Fire damaged trees converted into pellets

In 2015, the Bobtail Lake fire burned more than 25,000 hectares of land west of Prince George, BC. In the past these trees would have been left to decay, slowly emitting carbon and wasting a valuable resource. In 2019, a BC-based bioenergy company, began savage harvesting the damaged trees, converting them to pellets to produce clean energy for customers in Europe and Asia. In 2020, the company replaced the once scarred landscape with 1.1. million seedlings creating a carbon sink.

How do wood pellets compare to other products?

Long-living wood products produced from BC trees continue to store carbon while the leftover waste is turned into bioenergy. The cycle continues through reforestation, when new trees are planted and absorb more carbon as they grow. This makes woody biomass, such as wood pellets, a naturally renewable alternative to carbon-intensive sources of energy.

Globally, the energy industry is increasingly using wood pellets to replace fossil fuels to substantially lower greenhouse gas (GHG) emissions. For example, a study at a power station in the United Kingdom found that, even after accounting for fossil fuel emissions along the supply chain during harvesting, manufacturing and transportation, wood pellets lower GHG emissions by more than 80 percent compared to coal.