Canada's Energy Mix

Biomass

As renewable energy continues to grow in Canada’s energy mix, old energy resources are being reexamined in new ways. Energy created from biomass is used for creating biofuels and generating electricity. What exactly is biomass energy and how is it produced?

William Warby, Woodchip, https://www.flickr.com/photos/wwarby/12140895823/, (CC BY 2.0)

What is biomass and how is it used to produce energy?

The main forms of biomass in Canada include byproducts of the forestry industry and municipal waste. Burning biomass, particularly firewood for heating homes, is widespread in Canada. Wood pellets, mainly made of sawdust and other waste from saw-milling, are used both to produce heat and generate electricity. Other sources include agriculture and organic waste, such as animal manure and municipal sewage.

Burning wood is the long-standing method of converting biomass to heat. Other methods that produce heat or electricity include direct combustion, co-firing, gasification, pyrolysis and anaerobic digestion.

In its simplest form, the wood used in a fireplace to produce heat and light is biomass. However, new forms of biomass are being used to generate electricity and produce fuel as the demand for renewable energy grows.

Direct combustion, the most common method used for converting biomass, involves burning biomass in boilers. The heat from burning biomass creates steam, which spins a turbine connected to a generator. Co-firing, however, involves burning biomass with coal in a traditional power plant. This is one of the cheapest ways to produce electricity from biomass, but it is less environmentally friendly.

To gasify biomass, the product is heated at high temperatures in an oxygen-deprived environment to produce a biogas that can be burned for heating and power generation. Pyrolysis follows a similar process, but the gas is cooled quickly to create bio-oil, which can be burned like petroleum to generate electricity.

The final method used to convert biomass to energy is anaerobic digestion. Bacteria break down organic material, in the absence of oxygen, producing biogas as a by-product. Mixing plant and animal wastes with water in oxygen-free tanks can also create biogas. This process occurs naturally in landfill sites that have organic waste.

D-Kuru / CC BY-SA 3.0 AT (https://creativecommons.org/licenses/by-sa/3.0/at/deed.en)

How are biomass products and biofuels transported?

Biomass products, in solid, liquid or gas forms, need to be transported to customers by truck, rail or pipeline. However, individuals burning wood, a type of biomass, can use the energy for heating and cooking on the spot.

Sources of biomass are usually far from power grids and cities, making it difficult for the average person to use biomass-generated electricity. Several district heating systems in Canada use biomass—sometimes waste from nearby sawmills—to generate heat and/or electricity for buildings in a community.

In district heating systems, biomass is converted to heat and/or electricity through a variety of methods and sent to buildings through a network of underground insulated pipes. As more biomass plants are built, there may be a need for more transmission facilities.

Robin Zebrowski, Biofuel, https://www.flickr.com/photos/firepile/3863002217/, (CC BY 2.0)

How does the electricity produced from biomass travel to where it needs to go?

There are three stages in the electricity system — generation, transmission, and distribution. Generation is about producing electricity, transmission is about moving it, and distribution is about delivering it to individual customers.

Transmission lines carry electricity from generating stations to end users or consumers. When electricity is running through these lines, some electricity is lost due to resistance and dissipates as heat. To reduce the amount of electricity lost in transit, these transmission lines carry high voltage electricity.

Power generators produce low voltage electricity and in order for this electricity to be transported to where it needs to go, the voltage has to be increased. A “step up” transformer is used to convert it to a higher voltage that the transmission lines can carry. Once the electricity reaches its destination, a substation “step down” transformer converts it back to a lower voltage so that it can be used by consumers.

The last part of the electricity grid is the distribution network, which is essentially the network of wires that takes the electricity from the transformers and carries it to the end-users. Electric utilities are private companies or government organizations that handle the production, transmission and distribution of electricity. Managing the electricity grid is a complicated process and an important responsibility.

Canada is connected to the United States through an international network called the North American Power Grid. Along the U.S. border there are more than 35 transmission connections, which allow for a flexible and mutually beneficial trade in electricity between Canada and its neighbour.

What is biomass energy used for?

Biofuels, renewable liquid fuels made from biomass, are used to power vehicles or generate electricity through fuel cells. The two most common biofuels in Canada are ethanol, produced mainly from corn but also wheat and other feedstocks, and biodiesel, created from animal fats, cooking oil and canola oil.

With concerns about climate change and emissions polluting the environment, as well as skyrocketing oil prices, biofuels offer a greener alternative to fossil fuels. Ethanol can be added to gasoline, reducing the fossil fuel component in the gas and helping to decrease greenhouse gas emissions. Biodiesel cuts down reliance on regular diesel, also reducing greenhouse gas emissions. Biofuels can also be used to power fuel cells to generate electricity.

Electricity produced from biomass can be used in our homes and businesses for things like lighting, heating and cooling, and powering appliances and electronic devices. We live in a world dependent on electricity. From the refrigerator in your kitchen to the computer that you’re using to access this website, electricity is the thing that makes possible most of our modern-day conveniences.

Biodiesel is used as a fuel in many European countries, however, in Canada, it is still a relatively young industry. Biofuel production still faces many challenges and isn’t without controversy. Conservationists worry about the energy that is being used to grow the plant matter necessary for biofuel production and whether it is an efficient energy source.

 

Idaho National Laboratory, Biofuel feedstocks, https://www.flickr.com/photos/inl/9192395303/in/[email protected]/, (CC BY 2.0)

How does energy production from biomass impact the environment?

Burning biomass to generate electricity produces greenhouse gases (GHGs) and pollutants, the same as any fossil fuel. Biomass power generating plants release nitrogen oxides, sulphur dioxide and carbon dioxide. However, the carbon dioxide produced from biomass energy may not result in an increase of atmospheric carbon dioxide if the biomass resources originate from a sustainable source. If sustainably managed, biomass is considered to be a carbon neutral, renewable energy source.

However, the process of growing plants for biomass energy production requires water and land, and GHGs are emitted in the harvesting and transportation of the biomass. It is necessary to do more research into the long-term viability of using biomass energy, its environmental impacts, and the economic cost of pursuing it as an energy source.

It is difficult to measure the exact carbon footprint of biomass and bioenergy, as the resource can come from dedicated land, such as crops grown specifically for biomass, or undedicated land, such as forest or landfill sites. In general, bioenergy collected and burned from dedicated land is less sustainable than bioenergy from wastes, such as landfill gas or animal waste.

Where do we find biomass facilities in Canada?

There are small-scale, independent biomass facilities across much of Canada. British Columbia is the only province that makes use of biomass on a large scale and biomass supplies the province with about six per cent of its electricity. Other provinces with large-scale biomass facilities include: Alberta, Nova Scotia and New Brunswick.

Biomass is also frequently used to provide heat in northern communities, through burning wood in conventional wood stoves. 

Did you know?

Airlines are taking steps to be more fuel efficient, which is motivated by keeping costs down as much as it is by environmental concern. Various methods include using lighter material for onboard equipment, restricting the weight of luggage and charging for extra, and designing seats to both lighten the aircraft load and be more efficient with space. All these tweaks have some small impact, but they don’t take away from the fact that most aircraft still operate on kerosene, which is a fossil fuel. That is why the airline industry is looking for alternative fuels—a solution that can be integrated into the aircraft systems they currently have, while research continues on more long-term projects.

Realistically, the greenest and most efficient energy source for air travel in the near future will likely be biofuels. The plants used in biofuels, like camelina, could absorb CO2 while they grow, before releasing it back into the atmosphere when used as fuel. In addition, aircraft engines wouldn’t need to be modified because biofuel meets the same specifications as petroleum-based fuel.

In October 2012, Canada’s National Research Council (NRC) flew the world’s first civil plane, a Falcon 20, powered by 100 per cent unblended biofuel. Another plane flew behind the jet, collecting samples for emissions testing. The NRC found that biofuel was cleaner and just as efficient as regular aircraft fuel. Research into the environmental effects of biofuel use is still ongoing. In April 2017, Air Canada participated in the NRC’s Civil Aviation Alternate Fuel Contrail and Emissions Research project, which measured the exhaust trails of five biofueled flights between Toronto and Montreal.

Other studies, where biofuel has been blended with traditional jet fuel, have found that particle emissions were reduced by at least 50 per cent in the test flights. So, if biofuel is cleaner and airlines don’t have to invest in upgrading aircraft engines, why is biofuel not more widely used? The issue comes down to cost, which mainly stem from lack of infrastructure for biofuel production and distribution. Currently, biofuel is about four times more expensive than conventional fuel.

The drive for greener energy solutions will only become more urgent as the air travel industry continues to grow rapidly. In the United States, airports like LAX in Los Angeles, have started to use biofuel in regular commercial operations. In 2016, Air Canada began a three-year project to introduce biofuel into the fuel supply system at Montreal-Trudeau International Airport. Biofuel is still relatively new, but with time, it is expected that costs will go down and biofuel will become a more viable alternative fuel.