What is biomass?
What is biomass?
In ecological terms, biomass refers to any type of organic matter. When it comes to energy, biomass is any organic matter that can be used to generate energy, for example wood, forest residues or plant materials.
How is biomass used?
Biomass used and combusted for energy can come in a number of different forms, ranging from compressed wood pellets – which are used in power stations that have upgraded from coal – to biogas and biofuels, a liquid fuel that can be used to replace fossil fuels in transport.
The term biomass also refers to any type of organic material used for energy in domestic settings, for example wood burned in wood stoves and wood pellets used in domestic biomass boilers.
Biomass is organic matter like wood, forest residues or plant material, that is used to generate energy.
Where does biomass come from?
Biomass can be produced from different sources including agricultural or forestry residues, dedicated energy crops or waste products such as uneaten food.
Drax Power Station uses compressed wood pellets sourced from sustainably managed working forests in the US, Canada, Europe and Brazil, and are largely made up of low-grade wood produced as a byproduct of the production and processing of higher value wood products, like lumber and furniture.
Biomass producers and users must meet a range of stringent measures for their biomass to be certified as sustainable and responsibly sourced.
Is biomass renewable?
Biomass grown through sustainable means is classified as a renewable source of energy because of the process of its growth. As biomass comes from organic, living matter, it grows naturally, absorbing carbon dioxide (CO2) from the atmosphere in the process.
It means when biomass is combusted as a source of energy – for example for heat or electricity production – the CO2 released is offset by the amount of CO2 it absorbed from the atmosphere while it was growing.
- In 2019 biomass accounted for 6% of Great Britain’s electricity generation, more than 1/6 of the total generation of all renewable sources
- There is about 550 gigatonnes of biomass carbon on Earth in total. Humans make up around 1/10,000th of that mass.
- Modern biomass was first developed as an alternative for oil after its price spiked as a result of the 1973 Yom Kippur War
- The International Energy Agency (IEA) estimates bioenergy accounts for roughly 1/10th of the world’s total energy supply
Biomass is a renewable, sustainable form of energy used around the world.
How long has biomass been used as a source of energy?
Biomass has been used as a source of energy for as long as humans have been creating fire. Early humans using wood, plants or animal dung to make fire were all creating biomass energy.
Today biomass in the form of wood and wood products remains a widely used energy source for many countries around the world – both for domestic consumption and at grid scale through power stations, where it’s often used to replace fossil fuels with much higher lifecycle carbon emissions.
Drax Power Station has been using compressed wood pellets (a form of biomass) since 2003, when it began research and development work co-firing it with coal. It fully converted its first full generating unit to run only on compressed wood pellets in 2013, lowering the carbon footprint of the electricity it produced by more than 80% across the renewable fuel’s lifecycle. Today the power station runs mostly on sustainable biomass.
- How working forests ensure biomass and wood products are sustainable.
- Looking at the numbers behind the forests Drax sources its biomass from.
- Responsible sourcing biomass is key to ensuring a zero-carbon future.
- International Energy Agency expects the role of bioenergy to increase.
- Biomass energy’s journey from the earliest humans to today’s electricity.
- The biomass in forests goes beyond just plants.
How biomass wood pellet mills can help landowners grow healthy forests
International Paper’s pulp and paper mill, located in the Morehouse parish of Louisiana, had been in operation since 1927 and was once the largest employer in the area. However, as a result of the global recession of 2008, the company was forced to lay off over 550 employees and shut the facility. Other mills in the area have also reduced production including Georgia Pacific which let go around 530 people at its Crossett, Arkansas plant 18 miles to the north of Morehouse in 2019.
For an area dominated by forests, such as Northern Louisiana and Southern Arkansas, this decline in traditional markets came as a serious blow. It’s a region where a healthy market for wood products is vital for the local economy and, in turn, the health of the region’s forests. Luckily other wood product manufacturers and industries have since began to fill the gap.
Drax Biomass has opened a mill in Morehouse parish that uses some of the the low-grade wood previously used to supply the paper industry to produce compressed wood pellets, which are used to generate renewable electricity in the UK.
Commissioned in 2015, the plant employs 74 people and can produce as much as 525,000 metric tonnes of biomass pellets a year. This makes it an important facility for local employment and the wood market in the region. However, to ensure it is positively contributing to the area and its environment, the demand for wood must be sustainably managed.
Morehouse BioEnergy sources low-grade wood from a catchment area that covers a 60-mile radius and includes 18 counties in Arkansas and four in Louisiana.
As Drax Biomass doesn’t own any of the forests it sources wood products from, it regularly examines the environmental impact of its pellet mills on the forests and markets in which it operates. The aim is to ensure the biomass used by Drax to generate 12% of Great Britain’s renewable electricity is sustainably sourced and does not contribute to deforestation or other negative climate and environment impacts.
A new report by forestry research and consulting firm Forisk evaluates the impact of biomass pellet demand from Morehouse BioEnergy on the forests and wood markets within the mill’s catchment area.
It found that biomass demand in the region does not contribute to deforestation, nor increase forest harvesting above a sustainable level. Overall, growth of the region’s pine timberland, which supplies Morehouse BioEnergy, continues to exceed removals, pointing to expanding forest carbon and wood inventory.
Growing forests and increasing timber stocks
The study focuses on timberland – working forests – in the plant’s sourcing area, which the US Forestry Service categorises as productive land capable of providing timber on an industrial scale.
The timberland here is made up of 63% softwood trees, which includes pines, and 37% hardwoods such as oak. Pellet manufacturing as a whole (including other pellet producers in the area), accounts for only 6% of the demand for wood products in the region. Of that, Morehouse BioEnergy contributes to 4% of total pellet demand.
Lumber – such as sawtimber – makes up the bulk of demand for wood products, accounting for 46% of total demand, largely as a result of its high market value and landowners’ aims to extract maximum revenue from their pine stands.
However, the less valuable wood – parts of trees that are misshapen, too short or thin to be used for lumber – can be sold at a lower price to biomass pellet mills. This wood might previously have been sold to paper and pulp mills exclusively, but with International Paper’s departure, Morehouse BioEnergy now fills a part of that role.
Maintaining healthy markets for both high and low-value wood is key to enabling landowners to reforest areas once they have been harvested in the knowledge it will provide a valuable return in the future. Ultimately, however, the way forests are maintained depends on the individual landowners and how they want to use their land.
The advantages of corporate ownership
Morehouse BioEnergy’s catchment area covers 28,000 square kilometres of timberland, within which 96% of the timber is privately owned. While some of that is owned by families with small patches of productive land, 54% is held by corporate owners. This includes businesses such as real estate investment trusts (REITs) and timber investment management organisations (TIMOs), which advise institutional investors on how to manage their forest assets.
This high percentage of corporate ownership influences forest management and replanting, as owners look to maximise the value of forests and seek to continue to generate returns from their land.
“In general, corporate owners are spending more money on silviculture and actively managing their timber stands,” explains Forisk Consulting Partner Amanda Lang. “They are investing more in fertiliser, their seedlings and harvest control on pine stands, because that leads to larger trees of a higher quality and more profit in the long run.” This is reflected in the higher growth rates found in the private sector, leading to faster rates of carbon sequestration.
Smaller private landowners, meanwhile, may have other objectives for their land like recreation and hunting, in addition to timber income. As a result, some owners may be less inclined to intensively manage their timber stands, forgoing fertilisation and competition control (due to cost) and might harvest on a less regular basis. Although these landowners may not be maximising the productivity of their timber resource to the same degree corporate owners do, their unique management often contribute to greater diversity on the landscape.
Demand and forest health
In 2018 the annual average price for a metric tonne of pine sawtimber in Morehouse BioEnergy’s catchment area was $25.71, down from a 10-year high of $31.60 in 2010. Similarly, pine pulpwood, from which biomass pellets are made, was valued at $7.75 per metric tonne in 2018, down from a 10-year high of $13 in 2010.
These low wood prices have caused many landowners to delay harvesting forests in hopes for a more lucrative wood price. As a result, pine timber inventories have grown across Morehouse BioEnergy’s catchment area. In 2010 the US Forest Service counted more than 167 million metric tonnes of pine inventory. By 2018 this had increased by more than 35% to reach 226 million.
The report suggests this price slump is an ongoing result of the 2008 recession, which greatly affected US house construction – one of the primary uses of sawtimber and many other types of wood products in the US. Some areas have already seen sawtimber prices increase as they recover from the recession, however, the report suggests this is not spread evenly on a national level.
The inventory overhang in Morehouse BioEnergy’s catchment area is expected to begin reversing in 2024 or 2025, as Lang explains: “We expect inventories to increase for a few more years and then start to decline. That said, inventories will remain higher than pre-recession levels.”
While high inventories suggest an abundant resource, lower inventory volumes are not indicative of declining or unhealthy forests. Rather, they can point to younger, growing forests that have recently been replanted, which will later grow to higher inventory volumes as they mature. Both suggest a healthy forestry industry in which landowners continue to reinvest in forests.
Overall, the analysis of the region points to healthy, growing forests and, importantly, a sustainable industry from which Drax can responsibly source biomass pellets. Ensuring the biomass used at Drax Power Station is sustainably sourced is crucial to its generation of renewable, carbon-neutral electricity, and in turn laying the path to negative emissions.
Read the full report: Morehouse, Louisiana Catchment Area Analysis. A short summary of its analysis and conclusions, written by our forestry team, can be read here. Explore every delivery of wood to Morehouse BioEnergy using our ForestScope data transparency tool.