Biomass: Sustainable Energy or Environmental Controversy? A Deep Dive into its True Impact
Biomass energy, derived from organic materials such as wood, agricultural residues, and waste, is often promoted as a sustainable alternative to fossil fuels. Proponents argue that it provides a renewable source of energy, contributing to energy security and reducing reliance on coal or gas. However, there is ongoing debate about its true sustainability and environmental impact, especially when biomass is scaled up to supply a significant share of a country's energy generation.
A key consideration in assessing biomass sustainability is its potential for carbon neutrality. This concept hinges on the idea that the CO₂ released during combustion is offset by the CO₂ absorbed by plants and trees during their growth. Critics, however, argue that the time it takes for this cycle to balance—often decades or longer—complicates the notion of biomass being genuinely carbon-neutral. Moreover, forests recovering from logging can act as a source of carbon for years after felling, further disrupting the balance. To fully grasp the impact of biomass, it’s essential to consider lifecycle emissions that include not only the combustion phase but also the emissions from harvesting, processing, and transporting biomass, as well as the loss of CO₂ absorption potential from felled mature trees. These factors play a significant role in determining whether biomass can be considered a climate-friendly energy source.
We know logged forests are still a source of carbon up to a decade after they have been logged, and that this primarily comes from organic matter in the soil or from rotting wood.
Beyond emissions, the biomass supply chain raises concerns about land use and biodiversity. As demand for biomass increases, so does the pressure on forests and natural ecosystems. The growing demand for biomass has led to the conversion of diverse ecosystems into uniform plantations or logging areas, which can harm biodiversity and disrupt ecosystems. While sustainable land management and responsible sourcing are needed to reduce these impacts, such practices are not consistently enforced across all regions.
The Drax Power Station: A Controversial Biomass Case Study
The Drax power station in North Yorkshire, UK, is one of the largest biomass power plants in the world and a pivotal case in the discussion of biomass sustainability. Originally a coal-fired power station, Drax shifted to burning wood pellets as part of its strategy to reduce its carbon footprint and transition to renewable energy. The facility now provides around 8% of the UK’s renewable power and accounts for approximately 4% of the nation’s total electricity generation.
Despite its significant contribution to renewable energy, Drax has faced scrutiny and criticism over the sustainability of its wood pellet sourcing and the net impact on emissions. The power station benefits from substantial government subsidies—amounting to over £500 million annually—to support its biomass operations. These subsidies have been a point of contention, as critics argue they support a technology that may not be as environmentally beneficial as it appears. In 2023 alone, Drax emitted around 11.5 million tonnes of carbon dioxide—despite being marketed as a cleaner energy source. This is largely due to the vast volume of wood pellets burned by the facility over the year, making Drax the largest single source of CO₂ emissions in the UK.
Looking forward, Drax’s strategy centers on expanding its biomass production. The company plans to increase its self-supply to 5 million tonnes by 2027, aiming to eventually double its pellet production capacity by 2030. This growth is intended to reduce dependency on external suppliers and establish a more self-sustaining business model. While these developments could position Drax as a major player in the global biomass market, concerns remain about the sustainability of scaling up production, particularly the impact on forests and emissions. Ensuring these expansions align with environmental goals will require transparent standards and comprehensive emissions accounting.
North American Forests and the Impact of Wood Pellet Production
Canada and the United States are major players in the global biomass industry, supplying wood pellets for power stations worldwide. Both countries have extensive forested areas rich in coniferous and mixed forests—Canada with 347 million hectares covering nearly 9% of the world’s total, and the USA with over 300 million hectares. Together, they have become leading exporters of biomass, providing resources to power plants like the UK’s Drax.
However, the rapid expansion of this industry has sparked growing concerns about its long-term sustainability and environmental impact. In Canada, where the coniferous forests cover around 68% of its total forest area, wood pellets are produced either as a primary product or as a byproduct alongside other forest commodities like lumber, tissue, and paper. This has led to the logging of nearly half a million hectares of forests annually. In the USA, states like Georgia, North Carolina, and Virginia have become hubs for biomass production, where pellet plants source wood from diverse landscapes, often including biodiverse-rich wetland forests.
Both countries’ forestry practices are under scrutiny for contributing to the degradation of critical carbon sinks and exacerbating emissions. In Canada, recent reports indicate that the logging industry is a major contributor to greenhouse gas emissions, responsible for over 10% of the country’s total annual emissions. Meanwhile, in the USA, the expansion of the biomass sector has led to the clearing of large tracts of forest, raising concerns about habitat loss, reduced biodiversity, and the destruction of ecosystems that store vast amounts of carbon.
In both regions, the growing demand for wood pellets—driven by international biomass markets—risks turning forests into net emitters of CO₂ faster than they can regenerate, especially when old-growth forests or mature carbon-rich ecosystems are targeted for logging. This trend, combined with the added pressures of wildfires, insect infestations, and natural decay, is pushing some forests beyond their capacity to recover and serve as effective carbon sinks.
The long-term implications of these practices are significant. Without stronger regulations and stricter sustainability standards, North American forests may continue to experience degradation, undermining the very climate goals that biomass energy is supposed to support. A number of key environmental groups from across Canada have voiced these concerns. Earlier this year, they penned an open letter to the UK government, urging it to stop incentivizing the mass burning of wood pellets sourced from clearcut forests and to stop falsely portraying this practice as clean energy. The letter highlighted the urgent need to rethink the sustainability of current biomass sourcing and to put an end to the degradation of old-growth and critical forest ecosystems.
Scientific evidence corroborated by the Canadian government shows that logging primary forests and exporting wood pellets to be combusted in power plants releases greenhouse gas emissions on par with fossil fuels, especially on the timescale that scientists say is urgent to reduce climate emissions to avoid irreversible tipping points.
While biomass proponents claim that tree planting efforts cancel out the emissions associated with logging forests and burning those pellets, experts estimate that the “carbon debt” from these operations can take hundreds of years to repay.
It is clear that the U.K.’s proposal would contribute to a carbon debt much longer than the country’s 2050 net zero target, and make the U.K. a laggard in the global fight against climate change.
The Need for Full Global Lifecycle Emissions Accounting
Ultimately, the case of biomass energy serves as a stark reminder that not all renewables are created equal. While certain types of fast-growing trees, agricultural residues, and dedicated energy crops may have potential for sustainable biomass production, sourcing wood from established forests and carbon-rich ecosystems is far more problematic. Converting these valuable carbon sinks into energy sources undermines global climate efforts, depletes biodiversity, and exacerbates emissions rather than mitigating them.
There are also ethical considerations to address. Should a country deplete forested areas and ecosystems across the globe to meet its own green energy quotas? By sourcing wood from regions like Canada and the U.S. to power biomass plants, countries risk shifting the environmental burden to other areas, disrupting local ecosystems, and leaving long-term damage in their wake. This raises fundamental questions about the fairness of exporting environmental costs while reaping the benefits of clean energy at home.
The sustainability of biomass hinges on responsible sourcing that avoids the degradation of forests and natural habitats. Full emissions accounting, covering every stage of the biomass supply chain, and strict environmental standards are crucial to ensuring that biomass doesn’t become another form of greenwashing. Achieving these goals requires transparent international frameworks and a firm commitment to preventing unintended harm. Without a critical reassessment of biomass sourcing practices, it risks contributing more to environmental degradation than to genuine climate solutions. If carefully managed and properly regulated, biomass could potentially still play a role in meeting global climate targets—but only if we move away from exploiting established forests and focus instead on truly renewable sources.