At a glance
A low-biomass clean power system for the UK is achievable, by Frankie Mayo. Ember, Dec. 11, 2024.
Electricity produced from biomass, known as bioenergy, is costly and heavily import-dependent. Despite being viewed as a renewable energy source, a substitute for fossil fuels and a way to reuse waste, it is not without environmental concerns. A report from Ember challenges the notion that bioenergy is a “necessary compromise” in the energy transition, underscoring the potential financial and environmental benefits of a low-biomass energy system. Based on data from the U.K.’s National Energy System Operator (NESO), the report shows that the U.K. can achieve a stable, decarbonized power system by 2030 with less reliance on biomass. The analysis suggests biomass power generation could be cut by 55 per cent, contributing just two per cent of total electricity. To make up the shortfall, renewables like wind and solar could supply over 80 per cent of demand, with gas rising by 2.9 TWh — less than one per cent of total generation — and power imports increasing by 10 per cent. The U.K. would remain a net exporter of energy, exporting 60 TWh annually. This could also bring cost savings. The report says that bioenergy was 80 per cent more expensive than gas this year and nearly double the cost of onshore wind.
Organizations
Key findings
- Biomass power generation can be reduced while maintaining grid stability: By 2030, the U.K. could reduce its bioenergy generation by 55 per cent. Biomass could supply just two per cent of total electricity generation, with wind and solar meeting over 80 per cent of demand.
- Bioenergy is among the most expensive power sources: In 2024, biomass power generation cost £138/MWh. It was 80 per cent higher than gas (£77/MWh) and nearly double that of solar (£70/MWh).
- Biomass use raises significant environmental concerns: The carbon savings associated with biomass are increasingly dubious. Evidence indicates potential harm such as causing deforestation for wood pellets.
- U.K. biomass reliance threatens energy security: This power source is highly dependent on foreign imports. In 2023, Drax Power Station consumed 5.8 million tonnes of wood pellets — 20 times the U.K.’s domestic production.
- The U.K. becomes a net electricity exporter with reduced biomass reliance: Even with a 55 per cent reduction in biomass generation, the U.K. would export 60 TWh annually.
- Wind and solar drive the transition to clean power: By 2030, wind capacity is expected to triple, supported by an increase of 82 GW in renewable energy. This enables a significant reduction in fossil fuel use.
Take a look
Source: Ember (2024), A low-biomass clean power system for the UK is achievable (CC-BY-4.0)
Bigger picture
Based on the pathway in the NESO’s Clean Power 2030, Ember’s modelling challenges long-held assumptions about the necessity of biomass. Its analysis shows that renewables could meet over 80 per cent of electricity demand when paired with robust grid integration and storage capacity. It also casts doubt on the carbon neutrality of biomass power, highlighting its environmental and economic drawbacks. Biomass accounted for 11 per cent of the U.K.’s electricity in 2022. The Drax power station in Yorkshire, which is the U.K.’s largest biomass plant, was responsible for four per cent of electricity in 2023. It was also the U.K.’s largest CO2 emitter. The European Academies Sciences Advisory Council finds woody biomass ineffective for climate mitigation. The BBC has reported old-growth forests in Canada were being cut down to make wood pellets.
Biomass also creates economic challenges. In 2024, biomass electricity cost £138/MWh — nearly double the cost of solar (£70/MWh) and significantly higher than offshore wind (£82/MWh) or gas (£77/MWh). This has also cost taxpayers, as Drax received £539 million in public subsidies in 2023. The plant’s dual role as both a consumer and producer of wood pellets has also created issues. During the 2022 European gas crisis, it prioritized selling wood pellets instead of generating electricity, leaving power plants idle and costing U.K. consumers an estimated £639 million in lost potential savings.
The report has relevance outside the U.K., too. Globally, biomass is the largest source of renewable energy, accounting for 55 per cent of renewable supply and more than six per cent of total energy use. The Joint Research Centre of the European Commission reported that forest-based industry by-products and recovered post-consumer wood supply about 50 per cent of wood used for bioenergy in the EU, with treetops, branches, and other residues contributing 17 per cent, and stem wood — low-quality material unsuitable for sawmills or pulp and paper — accounting for 20 per cent. Amid increasing concerns over environmental impacts, ensuring the least harmful types of biomass are used to produce bioenergy is arguably more critical than reducing its overall use.
Its discussion of energy security also has global resonance. The U.K. imports around 50 per cent of its gas and its large-scale biomass power generators are highly dependent on imports — a combined risk to the energy supply. In 2023, the Drax power station burned 5.8 million tonnes of wood biomass. This is about 20 times the annual domestic pellet production and Drax sourced none of it from the U.K. Other countries that rely heavily on fossil fuels, uranium or biomass imports for their energy generation should prioritize domestic clean energy for energy security, cost-effectiveness and resilience. The report should guide policymakers and investors towards the cheapest, cleanest and best energy generation for cutting emissions and utility bills while improving energy security.
Challenges and opportunities
Key barriers to energy transition progress presented by bioenergy in the U.K.:
- High costs of biomass power generation: Biomass electricity generation is among the most expensive sources of power. It costs nearly twice as much as onshore wind and 80 per cent more than gas in 2024, straining energy budgets and reducing affordability.
- Reliance on imported biomass fuel: The U.K. imports nearly all biomass fuel for electricity. This exposes its energy system to price volatility and geopolitical risks, similar to its reliance on imported gas.
- Debatable climate benefits: Growing scientific consensus suggests that biomass does not deliver emissions reductions.
- Dependence on aging thermal generation: The U.K.’s current reliance on biomass and gas as dispatchable power sources highlights gaps in innovative, cleaner alternatives like storage or advanced demand-side management.
To address these challenges, the report recommends:
- Accelerate renewable energy expansion: The report advises the U.K. could increase renewable energy capacity by 82 GW. This includes a tripling of wind capacity by 2030.
- Reevaluate the sustainability of biomass: Stakeholders must assess biomass’s lifecycle emissions and land-use impacts. Policymakers should shift subsidies toward renewables with proven environmental and cost benefits.
- Increase electricity imports from interconnected markets: Importing 6.9 TWh of electricity from Europe could help cover a substantial proportion of the shortfall from reducing bioenergy generation. Enhancing cross-border electricity trade balances renewable supply. It also mitigates energy security risks through regional cooperation and infrastructure upgrades.
In their own words
Reliance on imported biomass threatens the benefits of clean power. It is often more expensive than gas power with emissions potentially higher. Biomass power in a clean power system is assumed to be a necessary compromise, this modelling shows that is not so clear cut.
A low-biomass clean power system for the UK is achievable, by Frankie Mayo, Ember, Dec. 11, 2024.
Final thoughts
The Ember report recommends reducing the U.K.’s reliance on biomass while expanding wind and solar to achieve a decarbonized power system by 2030. The author argues this approach is both feasible and preferable to one in the NESO 2030 Clean Power report. That pathway depends more heavily on biomass — an expensive, import-dependent energy source with environmental concerns.
A discussion about the types of biomass used would have strengthened the report, as these significantly affect emissions and environmental impacts. Promoting transparency and accountability in supply chains is crucial to ensure that only sustainable sources, such as residues, wood waste and low-quality wood, are used. This aligns with the author’s acknowledgment that bioenergy will remain part of the U.K. energy mix, even with his recommended reductions.
The role of bioenergy with carbon capture and storage (BECCS) should also be considered, as many net-zero scenarios include it. The Drax power station has been developing BECCS technology since 2018. It plans to install two units by 2027 while expanding projects in the U.S. BECCS does present challenges, including land use for monocultures. This could affect biodiversity, food security and water availability. Bioenergy may also have to compete for feedstocks used by other low-carbon technologies, such as sustainable aviation fuels (SAF). Exploring how batteries and other storage technologies can balance a grid with high levels of variable renewables would further support the transition. This could reduce dependence on dispatchable thermal energy generation such as bioenergy and gas, providing a stable, low-carbon power system.
Download the full report originally published by Ember on Dec. 11, 2024.
