Author: Alice Roberts

Why and how is carbon dioxide transported?

What is carbon transportation?

Carbon transportation is the movement of carbon from one place to another. In nature, carbon moves through the carbon cycle. In industries like energy, however, carbon transportation refers to the physical transfer of carbon dioxide (CO2) emissions from the point of capture to the point of usage or storage.

Why does carbon need to be transported?

Anthropogenic (man-made) CO2 released in processes like power generation leads to the direct increase of CO2 in the atmosphere and contributes to global warming.

However, these emissions can be captured as part of carbon capture and storage (CCS). The CO2 is then transported for safe and permanent storage in geological formations deep underground.

Capturing and storing CO2 prevents it from entering the atmosphere and contributing to global warming. Processes that can deliver negative emissions – such as bioenergy with carbon capture and storage (BECCS) and direct air capture and storage (DACS) – aim to permanently remove CO2 from the atmosphere through CCS.

In CCS, carbon must be transported from the site where it’s captured to a site where it can be permanently stored. This means it needs to travel from a power station or factory to a geological formation like a saline aquifer or depleted oil and gas reservoirs.

As of September 2021, there were 27 operational CCS facilities around the world, with the combined capacity to capture around 40 million tonnes per annum (Mtpa) of CO2. It’s estimated that the UK alone has 70 billion tonnes of potential CO2 storage space in sandstone rock formations under the North Sea.

How is carbon transported?

CO2 can be transported via trucks or ships, but the most common and efficient method is by pipeline. Moving gases of any kind through pipelines is based on pressure. Gases travel from areas of high pressure to areas of low pressure. Compressing gas to a high pressure allows it to flow to other locations.

Gas pipelines are common all around the world, including those transporting CO2. In the US there are, for instance, more than 50 CO2 pipelines – covering around 6,500 km and transporting approximately 68 million tonnes of CO2 a year.

Gas takes up less volume when it’s compressed, and even less when it is liquefied, solidified, or hydrated. Therefore, before being transported, captured CO2 is often compressed and liquefied until it becomes a supercritical fluid.

In a supercritical state, CO2 has the density of a liquid but the viscosity (thickness) of a gas and is, therefore, easier to transport through pipelines. It’s also 50-80% less dense than water, with a viscosity that is 100 times lower than liquid.

This means it can be loaded onto ships in greater quantities and that there is less friction when it’s moving through pipes and, subsequently, into geological storage sites.

How safe is it to transport carbon?

It’s no riskier to transport CO2 via pipeline or ship than it is to transport oil and natural gas, and existing oil and natural gas pipelines can be repurposed to transport CO2.

To enable the safe use of CO2 pipelines, CCS projects must ensure captured CO2 complies with strict purity and temperature specifications, as well as making sure CO2 is dry and free from impurities that could impact pipelines’ operations.

Whilst there are a growing number of CCS transport systems around the world, CCS is still is a relatively new field but research is underway to identify best practises, materials and technologies to optimise the process. This includes research around potential risks and techniques for leak mitigation and remediation.

In the UK, the Health and Safety Executive regulates health, safety, and integrity issues for all natural gas pipelines, which are covered by legislation. The legislation ensures the safety of pipelines, pressure systems and offshore installations and can serve as a strong foundation for CO2 transport regulation.

Fast facts

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Cruachan Power Station: Protecting biodiversity while generating power

Key points:

  • The Scottish Highlands are home to a wide variety of landscapes, with a wealth of biodiversity that must be preserved.
  • Cruachan pumped storage hydro station sits within Ben Cruachan and has operated for nearly 60-years without damaging wildlife.
  • Regular surveys and reporting allow Drax to understand the health of different fauna and species over time.
  • It’s promising that even species of bird and insects that are declining in other parts of the UK are regularly spotted around Cruachan.
  • The expansion of the power station has required and will continue to need careful assessment of the area’s biodiversity to minimise any impact the project could cause.

The Scottish Highlands are home to some of the UK’s most stunning natural wonders. From dramatic plunging lochs to the craggy, ice capped Munros, the varied landscape holds some of the most biodiverse areas in the UK. The region’s fauna ranges from red deer to golden eagles, while its flora includes the ancient oak and moss-covered forests that make up the ‘temperate rainforest’ of the Atlantic coast.

Preserving these landscapes and the life that thrives in them is crucial to both the environment and economy of the region. It’s the job of Roddy Davies, Health, Safety, and Environmental Advisor at Drax’s Cruachan Power Station to ensure operations at the site do not damage the natural environment.

“This is a very biodiverse, rich environment. There are a lot of different species, a large variety of natural habitats and plant life,” says Davies. “It’s good that we can say we’ve operated here for nearly 60 years, and all of that is still there. It’s testament that we don’t have a demonstrable negative effect on the wildlife that lives around us.”

Source: Blue Leaf Nature

Energy storage inside a mountain

The pumped storage hydro station sits a kilometre inside Ben Cruachan, a Munro peak in the Western Highland region of Argyll and Bute. It’s not an area you would normally associate with power generation, but it’s perfect for pumped storage hydro. The site has two bodies of water at differing elevations, Loch Awe at the bottom and a reservoir at the top allowing Cruachan to generate power when it’s needed, as well as absorb electricity when there is an excess on the grid by pumping water back up the mountain. Storing it until power is needed and helping to keep the grid balanced.

The subterranean nature of the power station means the massive machinery, including the four reversible turbines, and the heat and noise they generate, is hidden underground.

Features on the surface are limited to a few buildings by the entrance tunnel at the banks of Loch Awe, and the dam which contains the upper reservoir on the slopes of Ben Cruachan, as well as several pylons and cables transporting electricity. Even the 316-metre buttress dam takes the landscape into account.

“When Cruachan was built in the ’50s and ’60s, the visual impact of it was very much in the minds of the people who built it and the authorities who approved it. The dam is almost impossible to see from a public place,” explains Davies. “Our presence on the surface is very limited. All the busy goings-on are underground. There’s lots of noise underground, but it doesn’t travel outside.”

Ensuring that the area surrounding Drax’s operation continues to function without damaging the surrounding environment is an ongoing process. Davies deploys annual biodiversity surveys and reporting that gives Drax over a decade of information and analysis to help identify trends.

The wildlife of Ben Cruachan

The Cruachan Power Station Biodiversity Survey for 2021 is the 11th completed by Blue Leaf Nature, a biodiversity service provider. The comprehensive report highlights the incredible diversity of fauna surrounding Cruachan, some of which are declining in other parts of the country.

While the majestic red stags found in other parts of the Highlands are extremely uncommon around Cruachan, 2021 was a particularly exciting year for other types of large mammals. Pine martens – a cat-sized relative of the weasel – are relatively common, appearing alongside red squirrels, red foxes, and otters. Badgers were also added to the site’s list of species for the first time.

Source: Blue Leaf Nature

Mammals, however, are exceeded by the range of birds found around Cruachan, with 53 different species spotted in 2021. Of these, 17 species appear on the Birds of Conservation Concern Five’s red list, the highest threat status to the UK’s bird population, including the Ring Ouzel, Yellowhammer and Tree Pipet. A further 27 appear on the Regional International Union for the Conservation of Nature (IUCN) Red List of Threatened Species. Additionally, six of the spotted species are considered endangered (including Herring Gull and Northern Wheatear) and 11 vulnerable by the IUCN.

Sightings of these threatened species around Cruachan come despite particularly unfavourable weather in 2021. One of the driest Aprils on record followed by an exceptionally wet May disrupted the bird breeding season. This in turn resulted in a difficult nesting season, exacerbated by food shortages due to the weather’s effect on insect life.

In the report’s survey of invertebrates, 150 different species were recorded in 2021, down from 170 in 2018. However, it’s promising that among Cruachan’s creepy-crawlies are many that are in decline elsewhere in the UK, with the numbers of some important insect types are increasing. Dragonfly and damselfly species, for example, increased from five in the previous survey to nine in 2021.

Moths and butterflies are particularly important to monitor, as Davies explains: “they’re a very strong indicator species for the health and quality of an ecosystem. They’re also very sensitive to climatic changes and  react quickly to temperature change.”

Source: Blue Leaf Nature

In 2021, 78 moth species were recorded around Cruachan, including one of Butterfly Conservation’s noted priority species (Yellow-ringed carpet), as well as six species that feature on IUCN’s red or amber lists. There were 11 butterfly species recorded in 2021, including four priority species, as well as two newly spotted species: the Small Copper and the Chequered Skipper.

That species in decline around the country are increasingly thriving at Cruachan is further testament to the power station’s lack of disruption to the environment. And as the UK’s electricity system continues to evolve, and Cruachan power station with it, closely observing the surrounding environment and its inhabitants will become even more important.

Expanding Cruachan while preserving nature

While Cruachan first started generating and storing power in the 1960s, its capabilities are becoming ever more critical as the national grid decarbonises and power generation becomes increasingly decentralised. This is why Drax is undertaking an ambitious project to expand Cruachan.

Cruachan 2 would add a further 600 MW of generation capacity to the plant for a total of 1.04 GW of power. By providing stability services to the grid, the expansion could enable an additional 300-gigawatt hours of renewable power to come online.

Source: Blue Leaf Nature

The project is epic in scale. New underground tunnels and subterranean caverns will house the reversible pump-turbines and will be carved out of the mountain, vastly increasing the size of the power station. But as with any activity in such a landscape, careful planning is essential. Detailed surveys and assessments of the area are a key requirement for planning approval.

“We need to acknowledge what’s here and show that we understand what surveys have found,” says Davies. “Then we have to present our proposals for how we will protect them and mitigate any potential disturbance.”

An advantage of pumped storage hydro is that much of the intensive excavating and construction work will take place underground, with little disturbance on the surface. Cruachan 2 has the added benefit of utilising Cruachan’s existing infrastructure. For example, it would not require flooding a valley to create a new upper reservoir.

Ultimately, Cruachan’s half century-plus of operation has not damaged or degraded the biodiversity of the Western Highlands landscape. And Davies is keen to ensure that legacy is preserved: “As a company, it’s not just something we have to do; we have a moral responsibility to be a responsible operator and look after what’s around us.”

View the Cruachan Power Station Biodiversity Survey 2021 here and find out more about Green Tourism at Cruachan here

What is the carbon cycle?

What is the carbon cycle?

All living things contain carbon and the carbon cycle is the process through which the element continuously moves from one place in nature to another. Most carbon is stored in rock and sediment, but it’s also found in soil, oceans, and the atmosphere, and is produced by all living organisms – including plants, animals, and humans.

Carbon atoms move between the atmosphere and various storage locations, also known as reservoirs, on Earth. They do this through mechanisms such as photosynthesis, the decomposition and respiration of living organisms, and the eruption of volcanoes.

As our planet is a closed system, the overall amount of carbon doesn’t change. However, the level of carbon stored in a particular reservoir, including the atmosphere, can and does change, as does the speed at which carbon moves from one reservoir to another.

What is the role of photosynthesis in the carbon cycle?

Carbon exists in many different forms, including the colourless and odourless gas that is carbon dioxide (CO2). During photosynthesis, plants absorb light energy from the sun, water through their roots, and CO2 from the air – converting them into oxygen and glucose.

The oxygen is then released back into the air, while the carbon is stored in glucose, and used for energy by the plant to feed its stem, branches, leaves, and roots. Plants also release CO2 into the atmosphere through respiration.

Animals – including humans – who consume plants similarly digest the glucose for energy purposes. The cells in the human body then break down the glucose, with CO2 emitted as a waste product as we exhale.

CO2 is also produced when plants and animals die and are broken down by organisms such as fungi and bacteria during decomposition.

What is the fast carbon cycle?

The natural process of plants and animals releasing CO2 into the atmosphere through respiration and decomposition and plants absorbing it via photosynthesis is known as the biogenic carbon cycle. Biogenic refers to something that is produced by or originates from a living organism. This cycle also incorporates CO2 absorbed and released by the world’s oceans.

The biogenic carbon cycle is also called the “fast” carbon cycle, as the carbon that circulates through it does so comparatively quickly. There are nevertheless substantial variations within this faster cycle. Reservoir turnover times – a measure of how long the carbon remains in one location – range from years for the atmosphere to decades through to millennia for major carbon sinks on land and in the ocean.

What is the slow carbon cycle?

In some circumstances, plant and animal remains can become fossilised. This process, which takes millions of years, eventually leads to the formation of fossil fuels. Coal comes from the remains of plants that have been transformed into sedimentary rock. And we get crude oil and natural gas from plankton that once fell to the ocean floor and was, over time, buried by sediment.

The rocks and sedimentary layers where coal, crude oil, and natural gas are found form part of what is known as the geological or slow carbon cycle. From this cycle, carbon is returned to the atmosphere through, for example, volcanic eruptions and the weathering of rocks. In the slow carbon cycle, reservoir turnover times exceed 10,000 years and can stretch to millions of years.

How do humans impact the carbon cycle?

Left to its own devices, Earth can keep CO2 levels balanced, with similar amounts of CO2 released into and absorbed from the air. Carbon stored in rocks and sediment would slowly be emitted over a long period of time. However, human activity has upset this natural equilibrium.

Burning fossil fuel releases carbon that’s been sequestered in geological formations for millions of years, transferring it from the slow to the fast (biogenic) carbon cycle. This influx of fossil carbon leads to excessive levels of atmospheric CO2, that the biogenic carbon cycle can’t cope with.

As a greenhouse gas that traps heat from the sun between the Earth and its atmosphere, CO2 is essential to human existence. Without CO2 and other greenhouse gases, the planet could become too cold to sustain life.

However, the drastic increase in atmospheric CO2 due to human activity means that too much heat is now retained between Earth and the atmosphere. This has led to a continued rise in the average global temperature, a development that is part of climate change.

Where does biomass fit into the carbon cycle?

One way to help reduce fossil carbon is to replace fossil fuels with renewable energy, including sustainably sourced biomass. Feedstock for biomass energy includes plant material, wood, and forest residue – organic matter that absorbs CO2 as part of the biogenic carbon cycle. When the biomass is combusted in energy or electricity generation, the biogenic carbon stored in the organic matter is released back into the atmosphere as CO2.

This is distinctly different from the fossil carbon released by oil, gas, and coal. The addition of carbon capture and storage to bioenergy – creating BECCS – means the biogenic carbon absorbed by the organic matter is captured and sequestered, permanently removing it from the atmosphere. By capturing CO2 and transporting it to geological formations – such as porous rocks – for permanent storage, BECCS moves CO2 from the fast to the slow carbon cycle.

This is the opposite of burning fossil fuels, which takes carbon out of geological formations (the slow carbon cycle) and emits it into the atmosphere (the fast carbon cycle). Because BECCS removes more carbon than it emits, it delivers negative emissions.

Fast facts

  • According to a 2019 study, human activity including the burning of fossil fuels releases between 40 and 100 times more carbon every year than all volcanic eruptions around the world.
  • In March 2021, the Mauna Loa Observatory in Hawaii reported that average CO2 in the atmosphere for that month was 14 parts per million. This was 50% higher than at the time of the Industrial Revolution (1750-1800).
  • There is an estimated 85 billion gigatonne (Gt) of carbon stored below the surface of the Earth. In comparison, just 43,500 Gt is stored on land, in oceans, and in the atmosphere.
  • Forests around the world are vital carbon sinks, absorbing around 7.6 million tonnes of CO2 every year.

Go deeper

How biomass can enable a hydrogen economy

Key points:

  • Hydrogen as a fuel offers a carbon-free alternative for hard-to-abate sectors such as heavy road transport, domestic heating, and industries like steel and cement.
  • There are several methods of producing hydrogen, the most common being steam methane reforming, which can be a carbon-intensive process.
  • Biomass gasification with CCS is a form of bioenergy with carbon capture and storage (BECCS) that can produce hydrogen and negative emissions – removing CO2 permanently from the atmosphere.
  • The development of both BECCS and hydrogen technologies will determine how intrinsically connected the two are in a net zero future.

Reaching net zero means more than just transitioning to renewable and low carbon electricity generation. The whole UK economy must transform where its energy comes from to low-emissions sources. This includes ‘hard-to-abate’ industries like steel, cement, and heavy goods vehicles (HGVs), as well as areas such as domestic heating.

One solution is hydrogen. The ultra-light element can be used as a fuel that when combusted in air produces only heat, water vapour, and nitrous oxide. As hydrogen is a carbon-free fuel, a so-called ‘hydrogen economy’ has the potential to decarbonise hard-to-abate sectors.

While hydrogen is a zero-carbon fuel its production methods can be carbon-intensive. For a hydrogen economy to operate within a net zero UK carbon-neutral means of producing it are needed at scale. And biomass, energy from organic material – with or without carbon capture and storage (in the case of BECCS)– could have a key role to play.

In January 2022, the UK government launched a £5 million Hydrogen BECCS Innovation Programme. It aims to develop technologies that can both produce hydrogen for hard-to-decarbonise sectors and remove CO2 from the atmosphere. The initiative highlights the connected role that biomass and hydrogen can have in supporting a net zero UK.

Producing hydrogen at scale

Hydrogen is the lightest and most abundant element in the universe. However, it rarely exists on its own. It’s more commonly found alongside oxygen in the familiar form of H2O. Because of its tendency to form tight bonds with other elements, pure streams of hydrogen must be manufactured rather than extracted from a well, like oil or natural gas.

As much as 70 million tonnes of hydrogen is produced each year around the world, mainly to make ammonia fertiliser and chemicals such as methanol, or to remove impurities during oil refining. Of that hydrogen, 96% is made from fossil fuels, primarily natural gas, through a process called steam methane reforming, of which hydrogen and CO2 are products. Without the use of carbon capture, utilisation, and storage (CCUS) technologies the CO2 is released into the atmosphere, where it acts as a greenhouse gas and contributes to climate change.

Another method of producing hydrogen is electrolysis. This process uses an electric current to break water down into hydrogen and oxygen molecules. Like charging an electric vehicle, this method is only low carbon if the electricity sources powering it are as well.

For electrolysis to support hydrogen production at scale depends on a net zero electricity grid built around renewable electricity sources such as wind, solar, hydro, and biomass.

However, bioenergy with carbon capture and storage (BECCS) offers another means of producing carbon-free renewable hydrogen, while also removing emissions from the atmosphere and storing it – permanently.

Producing hydrogen and negative emissions with biomass 

Biomass gasification is the process of subjecting biomass (or any organic matter) to high temperatures but with a limited amount of oxygen added that prevents complete combustion from occurring.

The process breaks the biomass down into a gaseous mixture known as syngas, which can be used as an alternative to methane-based natural gas in heating and electricity generation or used to make fuels. Through a water-gas shift reaction, the syngas can be converted into pure streams of CO2 and hydrogen.

Ordinarily, the hydrogen could be utilised while the CO2 is released. In a BECCS process, however, the COis captured and stored safely and permanently. The result is negative emissions.

Here’s how it works: BECCS starts with biomass from sustainably managed forests. Wood that is not suitable for uses like furniture or construction – or wood chips and residues from these industries – is often considered waste. In some cases, it’s simply burnt to dispose of it. However, this low-grade wood can be used for energy generation as biomass.

When biomass is used in a process like gasification, the CO2 that was absorbed by trees as they grew and subsequently stored in the wood is released. However, in a BECCS process, the CO2 is captured and transported to locations where it can be stored permanently.

The overall process removes CO2 from the atmosphere while producing hydrogen. Negative emissions technologies like BECCS are considered essential for the UK and the world to reach net zero and tackle climate change.

Building a collaborative net zero economy  

How big a role hydrogen will play in the future is still uncertain. The Climate Change Committee’s (CCC) 2018 report ‘Hydrogen in a low carbon economy’ outlines four scenarios. These range from hydrogen production in 2050 being able to provide less than 100 terawatt hours (TWh) of energy a year to more than 700 TWh.

Similarly, how important biomass is to the production of hydrogen varies across different scenarios. The CCC’s report puts the amount of hydrogen produced in 2050 via BECCS between 50 TWh in some scenarios to almost 300 TWh in others. This range depends on factors such as the technology readiness level of biomass gasification. If it can be proven – technical work Drax is currently undertaking – and at scale, then BECCS can deliver on the high-end forecast of hydrogen production.

The volumes will also depend on the UK’s commitment to BECCS and sustainable biomass. The CCC’s ‘Biomass in a low carbon economy’ report offers a ‘UK BECCS hub’ scenario in which the UK accesses a greater proportion of the global biomass resource than countries with less developed carbon capture and storage systems, as part of a wider international effort to sequester and store CO2. The scenario assumes that the UK builds on its current status and continues to be a global leader in BECCS supply chains, infrastructure, and geological storage capacity. If this can be achieved, biomass and BECCS could be an intrinsic part of a hydrogen economy.

There are still developments being made in hydrogen and BECCS, which will determine how connected each is to the other and to a net zero UK. This includes the feasibility of converting HGVs and other gas systems to hydrogen, as well as the efficiency of carbon capture, transport and storage systems. The cost of producing hydrogen and carrying out BECCS are also yet to be determined.

The right government policies and incentives that encourage investment and protect jobs are needed to progress the dual development of BECCS and hydrogen. Success in both fields can unlock a collaborative net zero economy that delivers a carbon-free fuel source in hydrogen and negative emissions through BECCS.

Storage solutions: 3 ways energy storage can get the grid to net zero

Key points:

  • Energy storage plays a crucial role in the UK electricity system by not only providing reserve power for when demand is high but also absorbing excess power when demand is low.
  • The UK’s electricity system’s growing dependency on intermittent renewables means the amount of energy storage needed will increase to as much as 30 GW by 2050.
  • There are three different durations of energy storage needed to help balance the grid: short-term, day-to-day and long term.
  • It will take a range of technologies including batteries, pumped storage hydro and new approaches to meet the storage demands of a net zero grid.

When you turn on a lightbulb – in 10, 20, or 30 years – the same thing will happen. Electricity will light up the room. But where that electricity comes from will be different. As the country moves toward net zero emissions, low carbon and renewable power sources will become the norm. However, it’s not as simple as swapping in renewables for the fossil fuels the grid was built around.

Weather dependant sources, like wind and solar, are intermittent – meaning other sources are needed at times when there’s little wind or no sunshine to meet the country’s electricity demand. Equally as challenging to manage, however, is what to do when there’s an excess of power being generated at times of low demand.

Energy storage offers a low carbon means of delivering power at times of low supply, as well as absorbing any excess of generated power when demand is low, helping to balance and stabilise the grid. As the electricity system transforms through a range of low-carbon and renewable technologies, the amount of energy storage on the UK grid will need to expand from 3 GW of today to over 30 GW in the coming decades.

The storage solution

Even as the UK’s electricity system transforms, from fossil fuels to renewables, the way the grid operates remains primarily the same. Central to that is the principle that the supply of electricity being generated must always match the demand on a second-by-second basis.

Too little or too much power on the system can cause power outages and damage equipment. National Grid needs to be able to call on reserve power sources to meet demand when supply is low or pay to curtail renewable sources’ output when demand drops. During the summer of 2020, for example, lower demand due to Covid-19 coupled with high renewable output resulted in balancing costs 40% above expectations.

“There is a lot of offshore wind coming online in Scotland, as much as 11 GW by 2030 and a further 25 GW planned,” explains Steve Marshall, a Development Manager at Drax.

Offshore wind farm along the coast of Scotland

“It’s great because it increases the amount of renewable power on the system, but the transmission lines between Scotland and England can become saturated as much as 30-40% of the time because there is too much power.”

Electricity storage can provide a source of reserve power, as well as absorb excess electricity. These capabilities are crucial for balancing the grid and ensuring that frequency remains within a stable operating range of 50 Hertz, as well as providing other ancillary services.

Whether it’s absorbing power or delivering electricity needed to keep the grid stable, in energy storage, timing is everything.

There are three main time periods electricity storage needs to operate over:

  1. Fast-acting, short term electricity

Because electricity supply must always match demand, sudden changes mean the grid needs to respond immediately to ensure frequency and voltage remain stable, and electricity safe to use.

Batteries are considered the fastest technology for responding to a sudden spike in demand or an abrupt loss of supply.

Battery technology has evolved rapidly in recent decades as innovations like lithium-ion batteries, such as those used in electric cars, and emerging solid-state batteries become more affordable and more commonplace. This makes it more feasible to deploy large-scale installations that can absorb and store excess power from the grid.

“Batteries are good for near-instantaneous responses. It can be a matter of milliseconds for a battery to deploy power,” says Marshall. “If there’s a sudden problem with frequency or voltage, batteries can respond – it’s something that’s quite unique to them.”

The speed at which batteries can deploy and absorb electricity makes them useful grid assets. However, even very large battery setups can only discharge power for around two hours. If, for example, the wind dropped off for a long period the grid needs a longer-duration supply of stored power.

  1. Powering day-to-day changes in supply, demand, and the grid

When it comes to managing the daily variations of supply and demand the grid needs to be able to call on reserves of power for when there are unexpected changes in the weather or electricity demand from users. Pumped storage hydro power offers a low carbon way to provide huge amounts of electricity, quickly and for periods that can last as long as eight or even 24 hours.

The technology works by moving water between two reservoirs of water at different elevations. When there is demand for electricity water is released from the upper reservoir, which rushes down a series of pipes, spinning water turbines, generating electricity. However, when there is an excess of power on the electricity system the same turbines can reverse and absorb electricity to pump water from the lower to the upper reservoir, storing it there as a massive ‘water battery’.

Pumped storage hydro is a long-established technology, having been developed since the 1890s in Italy and Switzerland. In the UK today there are four pumped storage hydro power stations in Scotland and Wales, with a total capacity of 2.8 GW.

Among those is the Drax-owned Cruachan Power Station in the Scottish Highlands. The plant is made up of four generating/pumping turbines located inside Ben Cruachan between Loch Awe and an upper reservoir holding 10 million cubic metres of water.

Turbine Hall at Cruachan Power Station

Pumped hydro storage facilities can rapidly begin generating large volumes of power in as little as 30 seconds or less. The ability to switch their turbines between different modes – pump, generate, and spin mode to provide inertia to the gird without producing power – make pumped storage hydro plants versatile assets for the gird.

“How Cruachan operates depends on weather,” says Marshall. “We make as many 1000 mode changes a month, that’s how frequently Cruachan is called on by National Grid.”

As the electricity system transforms there will be a greater need for flexible energy storage like pumped storage hydro, this is why Drax is kickstarting plans to expand Cruachan Power Station, however, the specific conditions needed for such facilities can make new projects difficult and expensive.

Cruachan 2, to the east of the original power station, will add up to 600 MW in generating capacity, more than doubling the site’s total capacity to more than 1GW. By increasing the number of turbines operating at the facility it increases the range of services that the grid can call upon from the site.

  1. Long-term electricity solutions

However, storage technologies as they exist today cannot alone offer all the solutions the UK will need to achieve its net zero targets. While technologies like pumped storage can generate for the better part of a day, longer periods of unfavourable conditions for renewables will need new approaches.

In March 2021, for example, the UK experienced its longest cold and calm spell in more than a decade, with wind farms operating at just 11% of their capacity for 11 days straight, according to Electric Insights.

The shortfall in the country’s primary source of renewable power was made up for by gas power stations. But in a net zero future, such responses will only be feasible if they’re part of carbon capture and storage systems or replaced by other carbon neutral or energy storage solutions.

Generating enough power to supply an electrified future, as well as being able to take pressure off the grid and provide balancing services will require a range of technologies working in tandem over extended periods.

Interconnectors with neighbouring countries, for example, can work alongside storage solutions to shed excess power to where there is greater demand. Similarly, rather than curtailing wind or solar power, extra electricity could be used for electrolysis to produce hydrogen. Other functions may include demand side response where heavy power users are incentivised to reduce their electricity usage during peak periods helping to reduce demand.

To achieve stable, reliable, net zero electricity systems the UK needs to act now to not only replace fossil fuels with renewables but put the essential energy storage and balancing solutions in place, that means electricity is there when you turn on a lightbulb.

Full year results for the twelve months ended 31 December 2021

RNS Number : 6410C
Drax Group PLC
24 February 2022

Twelve months ended 31 December20212020
Key financial performance measures
Adjusted EBITDA (£ million) (1)(2)398412
Continuing operations378366
Discontinued operations – gas generation2046
Net debt (£ million) (3)1,044776
Adjusted basic EPS (pence) (1)26.529.6
Total dividend (pence per share)18.817.1
Total financial performance measures from continuing operations
Operating profit / (loss) (£ million)197(156)
Profit / (loss) before tax (£ million)122(235)

Will Gardiner, CEO of Drax Group, said:

Drax Group CEO Will Gardiner

Drax Group CEO Will Gardiner

“2021 was a transformational year for Drax as we became the world’s leading sustainable biomass generation and supply company, whilst continuing to invest in delivering positive outcomes for the climate, nature and people.

“Over the past ten years Drax has invested over £2 billion in renewable energy and has plans to invest a further £3 billion this decade, supporting the global transition to a low-carbon economy. Our investment has reduced our emissions from power generation by over 95% and we are the UK’s largest producer of renewable power by output. We are proud to be one of the lowest carbon intensity power generators in Europe – a significant transformation from being the largest coal power station in Western Europe.

“We have significantly advanced our plans for bioenergy with carbon capture and storage (BECCS) in the UK and globally. By 2030 we aim to deliver 12 million tonnes of negative emissions and lead the world in providing a critical technology which scientists agree is key to delivering the global transition to net zero.”

Financial highlights

  • Adjusted EBITDA £398 million (2020: £412 million)
  • Strong liquidity and balance sheet – £549 million of cash and committed facilities at 31 December 2021
    • Expect to be below 2x net debt to Adjusted EBITDA by the end of 2022
  • Total dividend – 10% increase to 18.8 pence per share (2020: 17.1 pence per share)
    • Proposed final dividend of 11.3 pence per share (2020: 10.3 pence per share)

Strategic highlights

  • Acquisition of Pinnacle Renewable Energy Inc. for C$385 million (£222 million) (enterprise value of C$796 million)
  • Sale of Combined Cycle Gas Turbine (CCGT) generation assets for £186 million
  • Development of the world’s leading sustainable biomass generation and supply company
    • Supply – 17 pellet plants and developments across three major fibre baskets, production capacity of c.5Mt pa
    • 22Mt (c.$4.5 billion) of long-term contracted sales to high-quality customers in Asia and Europe
    • 14Mt of own-use sales through 2026
    • Generation – 2.6GW of biomass generation – UK’s largest source of renewable power by output
  • Development of BECCS in UK
    • East Coast Cluster – selected as one of two priority carbon capture and storage clusters
    • Government – BECCS included in Net Zero Strategy and Interim Bioenergy Strategy
    • Drax Power Station – planning application started, technology partner selected and FEED study commenced

Strategic outlook – growth plans aligned with global low-carbon growth

  • To be a global leader in sustainable biomass
    • Targeting 8Mt pa of production capacity and 4Mt pa of biomass sales to third parties by 2030
  • To be a global leader in negative emissions
    • Targeting 12Mt pa of negative CO2 – UK and international BECCS
  • To be a UK leader in dispatchable, renewable generation
    • Key system support role for biomass and expansion of Cruachan Pumped Storage Power Station
  • All underpinned by continued focus on safety, sustainability and biomass cost reduction
  • Investments totalling £3bn in period to 2030, fully funded through cash generation
    • Pellet production, UK BECCS and Cruachan expansion

Future positive – people, nature, climate

  • CO2 – >95% reduction in generation emissions since 2012 – sale of CCGT generation assets and end of commercial coal in March 2021 and closure in September 2022 following fulfilment of Capacity Market agreements
  • Sustainable biomass sourcing
    • Science-based sustainability policy compliant with current UK and EU law on sustainable biomass
    • Biomass produced using sawmill and forest residuals, and low-grade roundwood, which often have few alternative markets and would otherwise be landfilled, burned or left to rot, releasing CO2 and other GHGs
    • Significant increase in sawmill residues used by Drax to produce pellets – 57% of total fibre (2020: 21%)
    • 100% of woody biomass produced by Drax verified against SBP, SFI, FSC®(4) or PEFC Chain of Custody certification with third-party supplier compliance primarily via SBP certification
    • Glasgow Declaration launched at COP26 to establish a world-wide industry standard on biomass sustainability
  • People – Diversity, Equity and Inclusion – female representation in the UK business increased to 36% (2020:34%)
  • Governance – two new North America based Non-Executive Directors – Kim Keating and Erika Peterman

Operational review

Pellet Production – acquisition of Pinnacle, capacity expansion and biomass cost reduction

  • Adjusted EBITDA (including Pinnacle since 13 April 2021) up 65% to £86 million (2020: £52 million)
    • Pellet production up 107% to 3.1Mt (2020: 1.5Mt), with 1.2Mt sales to third parties and increased own-use
    • Total $/t cost of production down 7% to $143/t(5) (2020: $153/t(5))
  • Developments in US southeast (2021-22) – addition of c.0.6Mt of new production capacity
    • Completion of LaSalle and Morehouse plant expansions
    • Commissioning of Demopolis and first satellite plant (Leola)
    • Commencement of construction of second satellite plant (Russellville)
  • Further opportunities for growth and cost reduction – increased production capacity, sales to third parties, continued operational efficiencies and improvement, wider range of sustainable biomass and technical innovation

Generation – dispatchable renewable generation and system support services

  • UK’s largest generator of renewable power by output – 12% of total
  • Adjusted EBITDA from discontinued CCGT generation assets £20 million (2020: £46 million)
  • Adjusted EBITDA from continuing operations £352 million (2020: £400 million)
    • Biomass – 5% increase in generation less major planned outage on CfD unit (successfully completed November 2021), higher cost from historic foreign exchange hedging and system charges
    • Pumped storage / hydro – good operational performance
    • Strong portfolio system support role (balancing mechanism, ancillary services and optimisation)
    • Limited role for coal in H2 at request of system operator
  • Ongoing cost reductions to support operating model for biomass generation at Drax Power Station from 2027
    • Reduction in fixed cost base – end of commercial coal operations March 2021, closure September 2022
    • Third biomass turbine upgrade, delivering improved thermal efficiency and lower maintenance cost
    • Trials to expand range of lower cost sustainable biomass – up to 35% blend achieved in test runs on one unit
  • As at 21 February 2022, Drax had 20.4TWh of power hedged between 2022 and 2024 on its ROC and hydro generation assets at £70.2/MWh, with a further 0.9TWh equivalent of gas sales (transacted for the purpose of accessing additional liquidity for forward sales from ROC units and highly correlated to forward power prices) plus additional sales under the CfD mechanism
Contracted power sales 21 February 2022202220232024
ROC (TWh(6))
ROC (£ per MWh)
Hydro (TWh)0.2--
Hydro (£ per MWh)90.9--
Gas hedges (TWh equivalent)(7)0.50.4
Pence per therm105101
CfD(6/8) typical annual output c.5TWh and current strike price £118.5/MWh

Customers – renewable power under long-term contracts to high-quality I&C customers and decarbonisation products

  • Adjusted EBITDA of £6 million inclusive of impact of mutualisation changes and Covid-19 (2020: £39 million loss)
  • Continued development of Industrial & Commercial (I&C) portfolio
    • Focusing on key sectors to increase sales to high-quality counterparties supporting generation route to market
    • Energy services to expand the Group’s system support capability and customer sustainability objectives
  • Rebranding of the Haven Power I&C business to Drax Energy Solutions
  • Closure of Oxford and Cardiff offices as part of Small & Medium-Size (SME) strategic review and continuing to evaluate options for SME portfolio to maximise value and align with strategy

Other financial information

  • Total operating profit from continuing operations of £197 million (2020: £156 million loss, including exceptional costs totalling £275 million principally in respect of the announced closure of coal operations)
  • Total profit after tax from continuing operations of £55 million including a £49 million non-cash charge from revaluing deferred tax balances following confirmation of UK corporation tax rate increases from 2023 (2020: loss of £195 million)
  • 2021 capital investment of £230 million (2020: £183 million) – continued investment in biomass strategy
  • 2022 expected capital investment of £230–250 million – £70-80 million maintenance, £20 million enhancements, £110-120 million strategic, (primarily biomass and BECCS), and £30 million other (primarily safety and systems)
    • Excludes any material investment in non-core Open Cycle Gas Turbine developments – continuing to evaluate options, including sale, but continue to invest as appropriate to fulfil obligations under the Capacity Market agreements and to maximise value from any sale. In the event of a sale Drax expects to recover any capital expenditure incurred during 2022, which could total up to £100 million
  • Group cost of debt below 3.5%
    • Refinancing of Canadian facilities (July 2021) with lower cost ESG facility following Pinnacle acquisition
  • Net debt of £1,044 million (31 December 2020: £776 million), including cash and cash equivalents of £317 million (31 December 2020: £290 million)
    • Expect net debt to Adjusted EBITDA below 2x by the end of 2022
Forward Looking Statements
This announcement may contain certain statements, expectations, statistics, projections and other information that are, or may be, forward-looking. The accuracy and completeness of all such statements, including, without limitation, statements regarding the future financial position, strategy, projected costs, plans, beliefs and objectives for the management of future operations of Drax Group plc (“Drax”) and its subsidiaries (the “Group”), are not warranted or guaranteed. By their nature, forward-looking statements involve risk and uncertainty because they relate to events and depend on circumstances that may occur in the future. Although Drax believes that the statements, expectations, statistics and projections and other information reflected in such statements are reasonable, they reflect the Company’s current view and no assurance can be given that they will prove to be correct. Such events and statements involve risks and uncertainties. Actual results and outcomes may differ materially from those expressed or implied by those forward-looking statements. There are a number of factors, many of which are beyond the control of the Group, which could cause actual results and developments to differ materially from those expressed or implied by such forward-looking statements. These include, but are not limited to, factors such as: future revenues being lower than expected; increasing competitive pressures in the industry; and/or general economic conditions or conditions affecting the relevant industry, both domestically and internationally, being less favourable than expected. We do not intend to publicly update or revise these projections or other forward-looking statements to reflect events or circumstances after the date hereof, and we do not assume any responsibility for doing so.

Results presentation and webcast arrangements

Management will host a webcast presentation for analysts and investors at 11:00am (UK Time) on Thursday 24 February 2022.

The presentation can be accessed remotely via a live webcast link, as detailed below. After the meeting, the webcast recording will be made available and access details of this recording are also set out below.

A copy of the presentation will be made available from 7:00am (UK time) on Thursday 24 February 2022 for download at:

Event Title: Drax Group plc: Full Year Results
Event Date: Thursday 24 February 2022
Event Time: 11:00am (UK time)
Webcast Live Event Link:
Conference call and pre-register Link:
Start Date:  Thursday 24 February 2022
Delete Date:  Friday 24 February 2023
Archive Link:


For further information, please contact: [email protected]

View investor presentation here

Capacity Market Agreements

RNS Number : 5553C
Drax Group PLC
23 February 2022

T-4 auction – provisional results for existing pumped storage and hydro assets

Drax confirms that it has provisionally secured agreements to provide a total of 621MW of capacity (de-rated 586MW) principally from its pumped storage and hydro assets(1). The agreements are for the delivery period October 2025 to September 2026, at a price of £30.59/kW(2), with income of around £18 million in that period. These are in addition to existing agreements which extend to September 2025.


Drax Investor Relations: Mark Strafford

+44 (0) 7730 763 949


Drax External Communications: Aidan Kerr

+44 (0) 7849 090 368



  • Cruachan Pumped Storage, the Galloway hydro scheme (Tongland, Kendoon and Glenlee) and three small legacy gas turbines at Drax Power Station (96MW, de-rated 92MW).
  • Capacity Market agreements stated in 2020/21 real-terms, with payments indexed to UK CPI.


Alabama Cluster Catchment Area Analysis

The area of timberland in the Alabama cluster catchment area has remained stable over the last 20 years, increasing slightly from 4.08 million ha to 4.16 million ha, an increase of 79 thousand hectares.  This area represents 79.6% of the total land area in 2020, up from 78.1% in 2020.  The total area of forestland and woodland was 86% of the catchment area in 2020, with farmland making up 13% and urban areas 1%.  This land base can be considered to be heavily forested and dominated by timberland.

Figure 1: Land Use Type – Alabama cluster

The timberland area is classified by growth rate potential, capable of achieving a minimum of 0.57 m3/ha/year.  More than 95% of the timberland area is in private ownership.  This proportion has remained stable since 2000 as shown in Figure 2.

Figure 2: Timberland Ownership Profile – Alabama cluster

The total standing volume, the amount of carbon stored in the forest area, has increased by 115 million m3 since 2000 an increase of 30%. Most of this increase has occurred since 2010, with 90 million m3 added to the inventory since this time, reflecting the maturing age class of the forest resource as it passes through the peak growth phase.  Almost all of this increase has been in the softwood pine forest area, with a combined increase of 86 million m3 since 2010.  Pine saw-timber and chip-n-saw both increased by 46% since 2010 and pine pulpwood by 25% over the same period. Suggesting that the average tree size is getting larger as the forest matures.

Figure 3: Standing Volume by Product Class – Alabama cluster

One measure of the sustainability of harvesting levels is to compare average annual growth against removals.  This comparison gives a growth drain ratio (GDR).  Where removals are equal to or lower than growth (a GDR of 1 or more) this is a measure of sustainability, where the ratio falls below 1, this can indicate that harvesting levels are not sustainable in the long-term.  Figure 4 shows that all pine product classes have a positive GDR since 2010.  In particular the pine pulpwood GDR ratio is in excess of 2 suggesting that there is a substantial surplus of this product category.  By contrast, the hardwood GDR for both saw-timber and pulpwood are both lower than 1 suggesting that harvesting levels for hardwood species should be reduced until growth can recover.

Figure 4: Growth Drain Ratio by Product Class – Alabama cluster

Figure 5 shows the maturing age class of the forest area, charting the change in annual surplus and deficit in each product class.  The trend shows that harvesting of pine saw-timber from 2000 to 2008 represented a deficit of growth compared to harvesting removals.  This indicates an immature forest resource with a low quantity of forest categorised as saw-timber, therefore harvesting volume in mature stands outweighed the growth in mid-rotation stands.  As the forest aged, and more standing timber grew into the saw-timber category, the surplus of annual growth compared to removals increased.  Saw-timber growth in 2020 was 3 million m3 higher than in 2000.  The surplus of pine pulpwood has remained positive and has increased substantially from 3 million m3 in 2000 to 6.5 million m3 in 2020 despite harvesting levels increasing slightly over this period.

Figure 5: Annual Surplus/Deficit of Growth and Removal by Product Class – Alabama Cluster

Biomass demand began in 2008 at a very small scale, representing just 0.5% of total pulpwood demand in the catchment area.  From around 2013 it began to increase and reached peak in 2015 with a total demand of 724,000 tons of pulpwood in that year, representing 8.1% of total pulpwood demand in the catchment area.  After that time, demand for pulpwood declined as pellet mills switched to mill residuals.  The latest data on pulpwood demand shows that the biomass sectors made up just 2.8% of total pulpwood demand in 2020 with just over 216,000 tonnes of total demand.  This demonstrates that the biomass and wood pellet sector is a very small component of the market in this region and unlikely to influence forest management decision making, as shown in Figure 6.

Figure 6: Pulpwood Demand by Market – Alabama Cluster

Pine pulpwood stumpage prices have declined significantly since a peak in 2013, falling from an annual high of $9.46 when demand was strongest to just $4.12 in 2020 as demand for pine pulpwood declined in 2020.  Pine saw-timber prices have seen a similar decline from a high point in the early 2000’s to a plateau from 2011 onwards.  Saw-timber stumpage more than halved in value over this period from $49 per ton to $22 per ton.  This can have a significant impact on forest management objectives and decision making.

Figure 7: Stumpage Price Change by Product Category – Alabama Cluster

Detailed below are the summary findings from Hood Consulting on the impact of biomass demand on key issues in the Alabama cluster catchment area.

Is there any evidence that bioenergy demand has caused the following:


No. US Forest Service (USFS) data shows that total timberland area has held steady and averaged roughly 4,172,000 hectares in the Alabama Cluster catchment area since Alabama Pellets-Aliceville started up in late-2012. More importantly, planted pine timberland (the predominant source of roundwood utilized by the bioenergy industry for wood pellet production) has increased more than 75,000 hectares (+4.9%) in the catchment area since Alabama Pellets’ startup in 2012.

A change in management practices (rotation lengths, thinnings, conversion from hardwood to pine)?

Inconclusive. Changes in management practices have occurred in the catchment area over the last two decades. However, the evidence is inconclusive as to whether increased demand attributed to bioenergy has caused or is responsible for those changes.

Clearcuts and thinnings are the two major types of harvests that occur in this region, both of which are long-standing, widely used methods of harvesting timber. TimberMart-South (TMS) data shows that the prevalence of thinnings temporarily increased in the Alabama Cluster market (from 2007-2013) due to the weakening of pine sawtimber markets. Specifically, challenging market conditions saw pine sawtimber stumpages prices decline from an average of $47 per ton from 2000-2006 to just over $23 per ton in 2011, or a roughly 50% decrease from 2000-2006 average levels. This led many landowners to refrain from clearcutting (a type of harvest which typically removes large quantities of pine sawtimber), as they waited for pine sawtimber prices to improve. However, pine sawtimber stumpage prices never recovered and have held between $22 and $25 per ton since 2011. Ultimately, landowners returned to more ‘normal’ management practices by 2014, with thinnings falling back in line with pre-2007 trends.

The catchment area has also experienced some conversion. Specifically, from 2000-2020, planted pine timberland increased more than 460,000 hectares while natural hardwood and mixed pine-hardwood timberland decreased a combined 390,000 hectares. Note that the increase in planted pine timberland and decrease in natural hardwood/mixed pine-hardwood timberland over this period were both gradual and occurred simultaneously. This suggests a management trend in which natural timber stands are converted to plantation pine following final harvest. It’s also important to note that there is little evidence that links these changes to increased demand from bioenergy, as this conversion trend begun years prior to the startup of Alabama Pellets and continued nearly unchanged following the pellet mill’s startup.

Diversion from other markets?

No. Demand for softwood (pine) sawlogs increased an estimated 12% in the catchment area from 2012-2020. Also, there is no evidence that increased demand from bioenergy has caused a diversion from other softwood pulpwood markets (i.e. pulp/paper). Also, even though softwood pulpwood demand not attributed to bioenergy is down 14% since Alabama Pellets-Aliceville’s startup in 2012, there is no evidence that increased demand from bioenergy has caused this decrease. Rather, the decrease in demand from non-bioenergy sources is due to a combination of reduced product demand (and therefore reduced production) and increased utilization of sawmill residuals.

An unexpected or abnormal increase in wood prices?

No. The startup of Alabama Pellets-Aliceville added roughly 450,000 metric tons of softwood pulpwood demand to the catchment area from 2012-2016, and this increase in demand coincided with essentially no change in delivered pine pulpwood (PPW) price over this same period. Ultimately, the additional demand placed on the catchment area following the startup of Alabama Pellets-Aliceville was offset by a decrease in demand from other sources from 2012-2016, and, as a result, delivered PPW prices remained nearly unchanged.

However, the Aliceville facility was shut down for a majority of 2017 due to the catastrophic failure of a key piece of environmental equipment, and this was followed by Alabama Pellets’ strategic decision to transition to residual-consumption only beginning in 2018, which eliminated more than 360,000 metric tons of annual softwood pulpwood demand from 2016-2018. Over this same period, softwood pulpwood demand from other sources also decreased nearly 360,000 metric tons. So, with the elimination of roughly 720,000 metric tons of annual softwood pulpwood demand from all sources from 2016-2018, delivered PPW prices in the catchment area proceeded to decrease more than 6% over this period. Since 2018, total softwood pulpwood demand has increased roughly 4% in the catchment area (due to increases in demand from non-bioenergy sources), and this increase that has coincided with a simultaneous 4% increase in delivered PPW price.

Statistical analysis did identify a positive relationship between softwood biomass demand and delivered PPW price. However, the relationship between delivered PPW price and non-biomass-related softwood pulpwood demand was found to be stronger, which is not unexpected given that pine pulpwood demand not attributed to bioenergy has accounted for 94% of total pine pulpwood demand in the catchment area since 2012. Ultimately, the findings provide evidence that PPW price is influenced by demand from all sources – not just from bioenergy or from pulp/paper, but from both.

Furthermore, note that Alabama Pellets’ shift to residual-consumption only beginning in 2018 resulted in no increase in pine sawmill chip prices, as the price of pine sawmill chips in the Alabama Cluster catchment area rather decreased from 2018-2020, despite a more than 100,000-metric ton increase in pine sawmill chip consumption by the Aliceville mill over this period.

A reduction in growing stock timber?

No. From 2012 (the year Alabama Pellets started up) to 2020, total growing stock inventory increased an average of 2.6% per year (+22% total) in the Alabama Cluster catchment area. Specifically, inventories of pine sawtimber and pine chip-n-saw increased 41% and 40%, respectively, while pine pulpwood (PPW) inventory increased 25% over this same period.

A reduction in the sequestration rate of carbon?

No. US Forest Service (USFS) data shows the average annual growth rate of total growing stock timber in the Alabama Cluster catchment area increased from 6.0% in 2012 to 6.2% in 2020, suggesting that the sequestration rate of carbon also increased slightly over this period.

Note that the increase in overall growth rate (and therefore increase in the sequestration rate of carbon) can be linked to gains in pine timberland and associated changes with the catchment area forest. Specifically, growth rates decline as timber ages, so the influx of new pine timberland (due to the conversion of both hardwood forests and cropland) has resulted in just the opposite, with the average age of softwood (pine) growing stock inventory decreasing from an estimated 35.4 years of age in 2000 to 33.2 years of age in 2010 and to 32.2 years of age in 2020 (total growing stock inventory decreased from 41.9 to 41.0 and to 40.4 years of age over these periods).

An increase in harvesting above the sustainable yield capacity of the forest area?

No. Growth-to-removals (G:R) ratios, which compare annual timber growth to annual timber removals, provides a measure of market demand relative to supply as well as a gauge of market sustainability. In 2020, the latest available, the G:R ratio for pine pulpwood (PPW), the predominant timber product utilized by the bioenergy sector, equaled 3.26 (recall that a value greater than 1.0 indicates sustainable harvest levels).

Moreover, note that the PPW G:R ratio has increased in the catchment area since the Aliceville mill’s startup in 2012, despite the associated increases in pine pulpwood demand. In this catchment area, pine pulpwood demand from non-bioenergy sources decreased more than 860,000 metric tons from 2012 to 2020, and this decrease more than offset any increase in demand from bioenergy.

Impact of bioenergy demand on:

Timber growing stock inventory

Neutral. According to USFS data, inventories of pine pulpwood (PPW) increased 25% in the catchment area from 2012-2020, and this increase in PPW inventory can be linked to both increases in pine timberland and harvest levels below the sustainable yield capacity of the forest area. Specifically, pine timberland (both planted and natural combined) increased more than 185,000 hectares in the catchment area from 2012-2020. Over this same period, annual harvests of PPW were 65% below maximum sustainable levels.

Timber growth rates

Neutral. The average annual growth rate of total growing stock timber increased from 6.0% in 2012 to 6.2% in 2020 in the Alabama Cluster catchment area, despite pine pulpwood (PPW) growth rate decreasing from 15.1% to 12.5% over this period. However, this decrease in PPW growth rate was not due to increased demand attributed to bioenergy but rather to the aging of PPW within its product group and its natural movement along the pine growth rate curve. Specifically, USFS data indicates the average age of PPW inventory in the catchment area increased from an estimated 13.4 years of age in 2012 to 13.6 years of age in 2020.

Forest area

Neutral. In the Alabama Cluster catchment area, total forest (timberland) area remained nearly unchanged (decreasing only marginally) from 2012-2020. However, pine timberland – the predominant source of roundwood utilized by the bioenergy industry for wood pellet production – increased more than 185,000 hectares over this period, and this increase can be linked to several factors, including conversion from both hardwood and mixed pine-hardwood forests as well as conversion from cropland.

Specifically, the more than 185,000-hectare increase in pine timberland from 2012-2020 coincided with a roughly 197,000-hectare decrease in hardwood/mixed pine-hardwood timberland and a more than 8,000-hectare decrease in cropland over this period. Furthermore, statistical analysis confirmed these inverse relationships, identifying strong negative correlations between pine timberland area and both hardwood/mixed pine-hardwood timberland area and cropland in the catchment area from 2012-2020.

Wood prices

Negative/Neutral. Softwood pulpwood demand attributed to bioenergy increased from roughly 80,000 metric tons in 2012 (the year Alabama Pellets-Aliceville started up) to more than 655,000 metric tons in 2015 (the year biomass demand reached peak levels). However, this roughly 575,000-metric ton increase in softwood biomass demand coincided with essentially no change in delivered pine pulpwood (PPW) price – which averaged $26.40 per ton in 2012 and $26.39 per ton in 2015. Ultimately, the additional demand placed on this catchment area following the startup of Alabama Pellets-Aliceville was offset by a more than 680,000-metric ton decrease in demand from other sources over this same period, and, as a result, delivered PPW prices remained nearly unchanged. Also note that Alabama Pellets’ strategic shift to consume residuals only (a transition that begun in 2018 and had been completed by 2019) resulted in a nearly 480,000-metric ton decrease in softwood biomass demand in the catchment area from 2015 to 2020. Over this same period, softwood pulpwood demand from other sources decreased more than 180,000 metric tons. In total, softwood pulpwood demand from all sources decreased more than 660,000 metric tons from 2015 to 2020, and this decrease in demand resulted in delivered PPW prices decreasing 5% over this period.

Statistical analysis did identify a positive relationship between softwood biomass demand and delivered PPW price. However, the relationship between delivered PPW price and non-biomass-related softwood pulpwood demand was found to be stronger, which is not unexpected given that pine pulpwood demand not attributed to bioenergy has accounted for 94% of total pine pulpwood demand in the catchment area since 2012. Ultimately, the findings provide evidence that PPW price is influenced by demand from all sources – not just from bioenergy or from pulp/paper, but from both.

Markets for solid wood products

Positive. In the Alabama Cluster catchment area, demand for softwood sawlogs used to produce lumber and other solid wood products has increased an estimated 12% since 2012, and this increase in softwood lumber production has consequentially resulted in the increased production of sawmill residuals (i.e. chips, sawdust, and shavings) – by-products of the sawmilling process and materials utilized by Alabama Pellets to produce wood pellets.

Moreover, the increased availability of sawmill residuals and lower relative cost compared to roundwood (after chipping and other processing costs are considered) led Alabama Pellets to make a strategic shift to utilize residuals only for wood pellet production beginning in 2019. So, not only has Alabama Pellets benefited from the greater availability of this lower-cost sawmill by-product, but lumber producers have also benefited, as Alabama Pellets has provided an additional outlet for these producers and their by-products.

Read the full report: Alabama Cluster Catchment Area Analysis

This is part of a series of catchment area analyses around the forest biomass pellet plants supplying Drax Power Station with renewable fuel. Others in the series can be found here

What is sustainable forest management?

Sustainable forest management is frequently defined in terms of providing a balance of social, environmental, and economic benefits, not just for today but for the future too. It might be seen as the practice of maintaining forests to ensure they remain healthy, absorb more carbon than they release, and can continue to be enjoyed and used by future generations.

To achieve this, foresters apply science, knowledge, and standards that help ensure forests continue to play an important role in the wellbeing of people and the planet.

Managed forests, also called working forests, fulfil a variety of environmental, social, and economic functions. These range from forests managed to attract certain desired wildlife species, to forests grown to provide saw timber and reoccurring revenue for landowners.

How are forests sustainably managed?

How forests are managed depends on landowner goals – managing for recreation and wildlife, focusing on maximising production of wood products, or both. Each forest requires management tailored to its owner’s or manager’s objectives.

There are many ways to manage forests to keep them healthy – there is no ‘one size fits all’ – but keeping track of how they are doing can be tricky. One alternative for monitoring forests is to use satellite imagery.

One common sustainable forestry practice is thinning, which involves periodically removing smaller, unhealthy, or diseased trees to enable stronger ones to thrive. Thinning reduces competition between trees for resources like sunlight and water, and it can also help promote biodiversity by creating more space for other forest flora.

The wood removed from forests through thinning is sometimes not high-quality enough to be used in industries such as construction or furniture. However, the biomass industry can use it to make compressed wood pellets; a feedstock for renewable source electricity.

By providing a market for low-quality wood, pellet production encourages landowners to carry out thinnings. This practice improves the health of the forest, and helps support better growth, greater carbon storage, and creates more valuable woodland.

Fast facts

What are the environmental benefits of sustainably managed forests?

Through their ability to act as carbon sinks, forests are an important part of meeting global climate goals like the Paris Agreement and the UK’s own target of reaching net zero emissions by 2050.

When managed effectively through thinning or active harvesting, and replanting and regeneration, forests can often sequester – or absorb and store – more carbon than forests that are left untouched, increasing productivity and improving planting material.

Harvesting trees before they reach an age when growth slows or plateaus can help prevent fire damage, pests, and disease, so timing of final cutting is important. Though the vast majority of timber from such cutting will go to other markets (construction, furniture etc) and secure higher prices from those markets, being able to sell lower quality wood for biomass provides the landowner with some extra revenue.

Sustainably managed forests also help achieve other environmental goals, such as sustaining biodiversity, protecting sensitive sites and providing clean air and water. Managed forests also have substantial water absorption capacity preventing flooding by slowing the flow of sudden downpours and helping to prevent nearby rivers and streams from overfilling.

Wood from working forests also help tackle climate change in that high-value wood from harvested trees can be used to make timber for the construction or furniture sectors. These wood products lock up carbon for extended periods of time, and the wood can be used at end-of life to displace fossil fuels. Using wood also means materials such as concrete, bricks or steel are not used, and these materials have a large carbon footprint compared to wood.

What are the socioeconomic benefits of sustainably managed forests?

There are also social and economic benefits to managing forests. Sustainably managed working forests make vital contributions both to people and to the planet.

The commercial use of wood in industries like furniture and construction drives revenue for landowners. This encourages landowners to continue to replant forests and manage them in a sustainable way that continues to deliver returns.

Healthy forests can also improve living standards for local communities for jobs and helping to address unemployment in rural regions. Managed forests can also improve access for recreation. On a larger scale, sustainable forestry can offer a valuable export for regions and nations and foster trade between countries.

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