Sustainable Energy Generation: Burning Trees

Selaine Saxby Excerpts

Tuesday 6th December 2022 Westminster Hall

[Selaine Saxby (North Devon) (Con)]

I beg to move,

That this House has considered the sustainability of burning trees for energy generation.

It is a pleasure to serve under you in the Chair, Mr Gray. I thank the Backbench Business Committee for finding time for this important debate.

In my mind, today’s debate is about changing scientific understanding as we decarbonise our energy supply. The burning of wood as a renewable energy source has been adopted by the UK and the EU as a sustainable option to replace coal. In the UK, we subsidise the use of biomass to generate energy by £1 billion. However, in recent years, scientists and industry have raised serious concerns about the actual benefit of burning wood for energy. I secured this debate so that we can have a discussion about how taxpayers’ money is being spent and whether, at this time of global energy disruption, we are investing in the best forms of energy generation for our planet and for our energy security.

Biomass became prominent when coal-fired power stations were converted into biomass power stations. That was subsidised to aid the phase-out of coal and originated at a time when biomass was cheaper than renewables such as wind and solar and had perceived additional benefits, such as providing consistent, reliable power. Now, however, Drax is the UK’s biggest single-point source of carbon dioxide emissions. Because of the technology installed, the power station must run predominantly on wood pellets and has only limited capacity for non-woody biomass such as energy crops and organic waste.

The whole lifecycle emissions of CO₂ per kWh are 41 grams for solar, 11 to 12 grams for wind and 948 grams for coal. For forest biomass, they are 1,079 grams. That is far from the assumed carbon-neutral outcome. The UK produces roughly 12% of its energy from biomass and 3% from coal. The UK’s carbon emissions have not dropped at the same rate as our reduction of coal would indicate. The reality is that more carbon is being put into our atmosphere currently than when we were burning coal.

The difference between the idea that burning wood for energy is renewable and the reality comes from two misrepresentations. Both come about from the wrong approach to the accounting for the carbon output. The emissions from cutting down trees are attributed to the land-use sector rather than the energy-generation sector. As we import the majority of our wood pellets, we are exporting our carbon emissions. Although that may look good, it does not achieve anything, as we all share our atmosphere and the effects that carbon emissions cause.

The Intergovernmental Panel on Climate Change allows such zero-rating of emissions based on the idea that every tree will be replanted and its replacement will harness the same level of carbon as its predecessor; unfortunately, that has proven not to be the case. Many studies have shown that the carbon payback times for forest biomass are decades or centuries away, depending on the type of forest cut down to produce the wood pellets.

We are entering a crunch point in our work to limit the effects of climate change, with tipping points in the melting of sea and glacial ice, sea-level rises, ocean acidification, permafrost melt and the Amazon biome. We do not have the time to wait decades or centuries for the carbon to be reabsorbed and sequestered; nor does such an approach fit in with the goal of carbon neutrality by 2050.

Trees only grow in their carbon-storing potential as they age. There is a very minimal decline in their efficiency as they photosynthesise and store CO₂ from the atmosphere, but that decline is far outweighed by their sheer size and capacity. A study carried out by 38 researchers across 15 countries measured 400 species across six continents. It found that 97% of trees grew more quickly as they aged and absorbed more carbon year on year. If a tree’s diameter grows 10 times as large, it will undergo a hundredfold increase in leaf mass and an increase in leaf area of between fiftyfold and a hundredfold.

Our forests are still the largest remover of carbon, and one study found that, across forests of all ages and types around the world, half the carbon is stored in the largest 1% of trees when measured by diameter. As trees age, they also store more carbon in the soil, so we are looking at not just our canopy but the carbon stored in the earth itself, much as we need to consider our peatlands and the blue carbon stored in the seabed.

The other issue with the accounting of emissions from the burning of biomass for energy is the carbon associated with the supply chain for sourcing the wood pellets required. The industry sources wood pellets from North America, eastern Europe, the Baltics and, historically, Russia. Covid and the war in Ukraine have significantly disrupted supply chains and put more pressure on available forests. Drax sources most of its wood pellets from North America. A BBC “Panorama” documentary has cast doubt on the claim that it just uses waste wood and has suggested that primary forests are harvested and timber- quality wood burned as biomass.

The Dogwood Alliance in Mississippi has been tracking the logging of forests in the south-eastern United States and the conversion of whole trees into wood pellets. The south-east is one of the most biodiverse areas of the United States, and another downside to the burning of wood for energy is the fact that such older and more mature forests are home to a greater diversity of flora and fauna. The wood pellets are shipped to the United Kingdom on enormous vessels that are in transit for 21 days. Drax receives 17 wood pellet deliveries a day, and the plant operates 24 hours a day, six days a week. The energy required to transport the pellets adds to their lifecycle emissions and uses up the very fossil fuels the pellets are supposed to replace.

This is not an attempt to discredit one company; it is about us better understanding what is going on in the name of renewable fuels and asking that a more rigorous analysis of the carbon cost of this form of power production be fully conducted—at one level, it makes sense because trees grow back—before we assume that we really are moving to a lower-carbon-generating fuel supply and that any subsidy that supports that reflects the true carbon cost of what is supposed to be carbon neutral.

I want to raise concerns about the industry’s efforts to store more carbon in an attempt to deliver negative emissions and remove carbon from the atmosphere. Although that is a laudable goal, and the bioenergy with carbon capture and storage—BECCS—system is included in the United Kingdom’s net zero pathway, it is important to note that it is based on the flawed accounting that calls burning biomass carbon neutral. It involves a number of risks and barriers.

BECCS is the process of capturing and permanently storing underground the carbon emitted by biomass energy generation. The carbon capture rate is not 100%. Research from Chatham House indicates that it is about 76%, and energy needs to be expended to maximise capture. The options are to maximise power generation or to maximise carbon dioxide capture.

The process would also be incredibly expensive—power stations are seeking new subsidies to develop BECCS, and it is projected that it would require £31.7 billion over 25 years, which is equivalent to £500 per person in the United Kingdom—and incredibly land hungry. It would require an area roughly 1.5 times the size of Wales to grow enough bioenergy crops to meet BECCS demand. That is 17% of the United Kingdom’s arable land.

Recently, global events have shown how important a reliable food supply is, and the United Kingdom must not reduce its domestic production of quality produce. There is already the challenge of finding the right balance of land for farming, living, energy production and industry, so using such a large percentage of our land for a form of expensive and unsustainable energy generation would be the wrong approach.

The Climate Change Committee has called on the Government to support domestic biomass supply to meet expected carbon-removal requirements for the industry; however, is that the answer? The United Kingdom is about to face a severe shortage of wood and is one of the least densely forested countries in Europe, at only 13% of land area. The idea that rather than using that wood in industry we should burn it flies in the face of the basics of reducing emissions. At the heart of what we are aiming to do is reducing our use of virgin products, reusing where possible and recycling where not, and looking at using such products for energy generation only once they have become waste.

When we log forests for wood products, the carbon remains sequestered for however long those products last—possibly decades or longer. I declare an interest as chair of the all-party parliamentary group for the wood panel industry. The industry is a UK success story, with gross value added in excess of £850 million per annum and an ability to meet 65% of the UK demand for wood panel products. It supports approximately 7,500 jobs across the UK and has an average salary of £36,000, which is significantly above the UK average. The industry has made great strides in supporting our net zero by 2050 targets and has had some success with efficient and carbon-negative processes.

The wood panel manufacturing sector uses more than 25% of the 11 million tonnes of wood delivered from UK forestry every year. The rise of the wood fuel sector, which itself consumes about 25% of the UK annual wood basket because it is subsidised, has distorted the market and created shortages in domestic supply. Manufacturing operations rely on the sustainable supply of wood materials such as forest roundwood and thinnings, sawmill products, and recycled wood, supplies of which are increasingly restricted, given the fact that the UK will reach peak wood availability in the early 2030s, followed by a forecast sustained drop soon after. We need to plant more trees, especially if we carry on relying on biomass for our energy generation.

The closure of the renewable heat incentive scheme to new entrants in 2021 was a welcome decision. Now is the time to transition to future support schemes that most strategically target taxpayers’ money and ensure a level playing field for all wood users. Will the Minister ensure that when the biomass strategy is released it does not contain a new tariff-based incentivisation scheme similar to the renewable heat incentive? Will he also clarify whether biomass is supported by the contract for difference subsidies? In 2020, the Government announced that they would exclude coal-to-biomass conversion projects from future rounds, starting with allocation round 4.

[Wera Hobhouse (Bath) (LD)]

Does the hon. Lady agree that it is extraordinary that the biomass industry is asking for a combined CfD that would combine biomass production and carbon capture and storage?

[Selaine Saxby]

I agree that that is part of the confusion in the entire strategy; we need urgent clarification. In AR4, dedicated biomass with combined heat and power were eligible to compete, although no contracts were awarded. The announcement of AR5, which starts in March 2023, has not come with any clarity on whether biomass will be eligible for that round.

The Government have done great work as we transition to net zero by 2050, but further investment in biomass is clearly the wrong strategy. It not only continues to contribute carbon to our atmosphere when we can now invest in significantly cleaner energy, but takes away from flourishing British businesses and exports our problems overseas. When the biomass strategy is released, I hope that the mounting evidence will be considered and that we can continue to increase investment in more sustainable energy sources rather than pursuing this path.

[James Gray (in the Chair)]

I am advised that the fire alarm that may have to occur does not affect Westminster Hall, and our debate can therefore continue as planned.

--- Later in debate ---

[The Minister for Energy and Climate (Graham Stuart)]

It is a pleasure to serve under your chairmanship, Mr Gray. I congratulate my hon. Friend the Member for North Devon (Selaine Saxby) on securing the debate and thank all right hon. and hon. Members for their participation.

My first reflection, having heard the tenor of the debate and the contributions so far, is that I have a bit of an uphill struggle to the persuade people in Westminster Hall of my case. It was noticeable in the contribution of the hon. Member for Southampton, Test (Dr Whitehead), given in his classically well-informed but downbeat style, that the position of His Majesty’s Opposition is to support the use of biomass. They think it does have a role, although the hon. Gentleman caveated that by saying that it was “not a large” contribution, which in the overall scheme of our energy use perhaps leaves a lot of unanswered questions. However, I welcome the fact that he said that.

My hon. Friend the Member for North Devon raised important questions about biomass sustainability. I welcome the opportunity to clarify both the type of material and the stringent requirements we have in place to ensure that we support the sustainable use of this valuable resource. Using sustainable biomass in energy generation in the UK’s power sector has helped to reduce the use of fossil fuels. In 2021, biomass made up 12.9% of total electricity generation and the flexible generation provided by biomass technologies helps to support and stabilise the grid. It is not comparable with renewables, which by their very nature are not dispatchable and available as and when they are required—unlike biomass.

The use of wood pellets for bioenergy production has attracted a lot of interest and it is right that operations are closely scrutinised. However, there are claims against wood pellet use for bioenergy from forests that misrepresent on-the-ground forestry practices. That is short-sighted and ignores the environmental and social benefits of sustainable forest practices and the role that forest-derived biomass plays in supporting them.

Policy decisions need to be based on facts and rigorous evidence gathering, not on inaccuracies and misconceptions. The use of biomass from sustainably managed forests in well supported by evidence and experts such as the International Energy Agency, which is the global authority on energy, and the Intergovernmental Panel on Climate Change, which I would have thought that Members present would regard as being particularly well placed to make judgments on the balances that need to be struck in coming up with policy, yet the tenor of today’s debate is to dismiss these global experts and the different organisations that have looked at this issue extensively and come to the conclusion that the use of biomass is sustainable and right.

[Selaine Saxby]

rose—

[Barry Gardiner]

rose—

--- Later in debate ---

[Graham Stuart]

I will write to the hon. Gentleman on that specific issue, as it is right that I give him a proper answer. On investigation, we do not find that the allegations that “Panorama” made are fundamentally sustained. The general process involves thinnings. Every managed forest has to be thinned in order to be sustainably managed, and thinnings sometimes include whole trees—that is the nature of forest management. If we do not do it, it does not have the desired effect. It is worth saying again to my hon. Friend the Member for North Devon that young, vigorous stands grow and sequester carbon at maximum speed. As stands get older, the tree canopy closes and individual trees begin to die off from self-thinning and other causes. Very old forest stands can reach a carbon-neutral equilibrium, whereby trees die and decay at approximately the same rate as they grow back.

It is worth saying that before thinnings were used for bioenergy and turned into pellets, they were typically burned to get rid of them. The idea that the use of biomass is taking away fundamental primary forest, which is being cut down even though there are better uses for it, is false, but I will write to the hon. Member for Brent North (Barry Gardiner) about the specifics of that. It is always possible that there are exceptions, but Canada and the United States have really strong forest management and sustainability practices, regulations and laws. We have looked closely at the issue, and if they wish to keep this business going and manage the crops of these forests, they have every incentive to maintain them.

I say to my hon. Friend the Member for North Devon that we could do with bringing in some experts, and I will hold a meeting. Let us have the scientists in and discuss some of this stuff—it would be an opportunity to talk about it further.

[Selaine Saxby]

I thank the Minister for giving way on this point, although I am very disappointed by the stance he is taking. Will he invite the 600 scientists who wrote to the Prime Minister earlier this week with their very detailed analysis? The professors with whom many of us in this room have spent much time understand that the science has evolved and that some of the information we used back in 2014 is no longer correct. We need to re-evaluate things; we cannot just get stuck on what we used to do in the past.

--- Later in debate ---

[Selaine Saxby]

I thank you, Mr Gray, for chairing the debate, and my colleagues for their contributions. I suspect we will return to the issue, and I would be happy to join the Minister in doing so.

As we move through the transition to net zero, it is vital that we understand that things are going to change, that the science has changed and that we are moving forward. When people first burned coal, they did not understand the damage they were doing to the planet, and I think the same is true for wood pellets. In 1959, plastic bags were invented to stop us cutting down trees to make paper bags, and we recognise now that that probably was not the right decision.

I hope that as the Minister reviews the matter and considers the release of his biomass strategy, he will find those same advisers who persuaded the former Secretary of State that importing trees to burn is not a sustainable practice in view of our intention to get to net zero by 2050. On the current path, we are simply not going to achieve that.

Question put and agreed to.

Resolved,

That this House has considered the sustainability of burning trees for energy generation.