A wood pellet is a high-density material, made from wood that has been exposed to heat and pressure, and can replace coal as a source of energy. 1 The European Union has classified, in its climate and energy program, wood pellets as a renewable energy. This has created an exponential demand in the UK and Europe, where coal power plants have been converted into wood pellet power plants. The wood pellet industry claims that this fuel is both low-cost and low-carbon and thus a great alternative to coal. In the UK, the Department of Energy and Climate Change has been encouraging companies since 2012 to convert their power plants from coal to wood pellets to meet the country’s renewable energy targets. 3
Wood pellets are mainly made and exported from the US, the largest producer in the world. 4 In 2014, 10 million tons were produced in the country and 6 million tons of capacity were under construction. 4
Source: euanmearns.com
Drax Group’s main asset is the Drax Power Station, opened in 1974, the UK’s largest power station and once the biggest emitter of carbon dioxide. Drax has six steam turbines, which used to all be fueled by coal. The electricity generated supplies about 7 percent of the energy consumed in the country, around 27 terawatt hours. 8 7
With the push of the government to convert coal power plants to wood pellet ones, Drax saw the opportunity to change its image, to become a first-mover in that industry and to make profits, thanks to the subsidies offered by the UK. Three of the six power units were thus converted to burn wood pellets instead of coal. 5 Thanks to that adaptation, in 2016 alone, Drax received 541 million pounds in subsidies. 7
Sixty-five percent of the energy produced by the Drax Group is now coming from biomass. 7 Drax claims that its three converted units emit 80 percent less carbon dioxide, compared to coal-fired units. 2 8 In 2016, 13 million tons of wood were burned in the power plant. More than half that wood comes from the United States. Their major supplier is an American company, called Enviva. 7
Unfortunately, not all critics agree that wood pellets are as renewable and green-friendly as Drax claims. Wood pellets also release carbon dioxide when burned. The wood pellet energy is argued to be renewable because the gas emitted will be captured again by new trees, planted to replace those used. 7 However, for wood pellets to be a renewable energy source, trees would need to be replanted at a sufficient rate to make up for the carbon dioxide emitted when producing energy. 4 This mainly depends on the origin of the wood. To achieve extensive carbon emission reductions, the wood used to make pellets should be low-value, such as tree tops, waste, residues, limbs, or trees removed to maximize the growth of a forest. 2
This is the origin of the wood pellets they purchase, Drax claims. They argue that their fuel is only coming from waste from sustainable forests and that the whole process is audited externally every year. 8 However, many critics and scientists have warned that the industry threatens the US ecosystems. Some specialists say that there is not enough waste and residue of wood to meet the demand in the US. Hence, the wood pellet industry must be using whole trees as well. 3 6 They argue that Enviva, for instance, often harvest whole trees, which will take decades to grow back. Some of those trees come from hardwood forests, which are hosting rich ecosystems. 3 7 It takes at least five decades for hardwood trees to grow again and capture enough carbon dioxide to compensate the gas emitted. 6
Moreover, wood pellets are less energy-intensive than coal is. Hence, to produce the same amount of energy, more wood pellets would need to be burned than coal. 3 More carbon dioxide would thus be emitted and cannot be offset right away. 7 This means that, for at least a few decades, carbon dioxide emissions will increase until the new trees planted have captured enough of the greenhouse gas. This timescale is too long when one think about the immediacy of the climate change problem. 4
To reassure the critics and reduce the bad publicity, Drax Group should probably have more stringent requirements of its suppliers, to track with certainty the origin of the wood. However, the best way for Drax Group to ensure the origin of its wood pellets and to take full responsibility would be to vertically integrate and produce the pellets themselves, which is something the group has started to do. Drax could also set up sustainable and renewable plantations, with enough trees of all ages to offset emissions immediately. However, replacing a forest by a plantation has a very negative impact on ecosystems. Thus, this should only be done if the land was previously exploited for other uses, such as agriculture.
If Drax is really serious about its commitment to the environment, it could push the governments it works with, for more stringent regulations on the sustainability of harvested forests and wood pellets, and for quotas on the quantity of wood pellets that can be burned per country, to reduce the incentives the wood pellet industry now has to use whole trees from forests to meet the demand.
Written by: Celine Stein
References
1 Rose Grant, Wood pellets proposed to replace black coal used by thermal power stations, ABC News, 14 October 2016.
2 James Tapsfield, EU renewable energy targets mean Britain spends hundreds of millions of pounds on wood pellets from US that do more damage to environment, study warns, Daily Mail, 23 February 2017.
3 Roger Drouin, Wood Pellets: Green Energy or New Source of CO2 Emissions? Yale Environment, 22 January 2015.
4 Tom Zeller Jr., Wood Pellets Are Big Business (And For Some, a Big Worry), Forbes, 1 February 2015.
5 Adam Vaughan, European commission approves Drax biomass subsidy, The Guardian, 19 December 2016.
6 NRDC, Think Wood Pellets are Green? Think Again, Issue brief, May 2015.
7 Frances Howe, No Drax! There’s nothing ‘sustainable’ about big biomass, The Ecologist, 10 April 2017.
8 Steve Connor, Green energy: How one power plant chips away at the UK’s carbon footprint, Independent, 4 January 2016.
I agree that coal-to-wood pellet conversion might not be a sustainable solution for the long-term. I see the conversion from coal to wood pellets as an interim step to move away from coal until the end of the design life-time of the existing plants.
Fracking was a transformative technology for US to retire coal and even nuclear plants. Perhaps, the planned LNG exports from the US might help Europe to reduce coal/wood while keeping CO2 emissions minimized for the mid-term. The long term solution still remains as a mystery as the energy sector has been rapidly transforming in the last two decades. In the long term, should we say “we are all dead, anyway”?
Celine, a very relevant topic. Having worked on a business case for wood-pellet manufacturing, I can share my perspective which you might find helpful.
1. The US is an opportunistic market. They produce wood-pellet just to sell to Europe, and not use it in their fossil-fuel based power generation. Only Europe is true to its aim of achieving a drastic reduction of CO2 emission and one way of achieving that is to use carbon-neutral fuel in the form of wood-pellet. So, wood-pellet is a long-term and sustainable solution and not a quick fix.
2. A new type of pellet is being innovated called ‘Black pellet’ which is almost as energy-intensive as coal. And thus it can completely replace coal.
3. Drax`s claim that it purchases wood pellets produced from sustainable forests and wood-waste is true because wood-pellet manufacturing is long-term game and manufacturers want to have a sustainable supply of wood, which is only possible if the forest resource is sustainable. In the current demand-supply scenario I don`t think the sustainability of the forest is a big issue but if the demand would increase to levels which can`t be sustained by replenished forests, then markets can get profit-hungry and might start sourcing wood from illegal sources.