The Drax power station in North Yorkshire was originally designed to burn locally mined coal. Since the early 2000s the power station has progressively converted to produce electricity from biomass, mainly in the form of wood pellets, largely sourced and imported from North America. The billions of pounds utilised to fund this conversion came principally from government subsidies; £4bn since 2012. By the time the current subsidies expire in 2027 it will have received another £6bn.
The climate cost of burning wood pellets
The UK government envisages biomass energy will be part of the fuel mix that will guarantee the energy security of the UK while meeting its 2050 net-zero targets.
Of the six units at Drax, four are burning biomass which provides around 6% of the UK’s energy mix. It contributes 20% of the UK’s ‘renewable energy’. The Partnership for Policy Integrity, a science-led environmental advocacy group, claims that carbon dioxide emissions at from wood-burning generation, measured at the power plant, are 150% those of coal.
The Drax Group, which also has hydroelectric plants in its portfolio (a climate-positive development for which they should be applauded) has an ambition to be carbon-negative by 2030.
The carbon accounting loophole
That the wood pellet fuel is considered ‘renewable’ is based on the fact that trees can be regrown, and this affects its life cycle assessment, (this has been called a ‘carbon accounting loophole’). Deforestation contributes to the greenhouse effect by reducing the removal of atmospheric carbondioxide (sequestration) by photosynthesis.
Researchers believe that harvesting trees for wood pellets creates a carbon debt, with a payback time of between 44 and 104 years well beyond 2050 net zero targets.
The two remaining units at Drax power station use coal or petroleum coke. Coal provides a small proportion of the UK energy mix at just 2%. At the government’s request, the coal units at Drax were put on standby as a critical tool for ‘keeping the lights on’ in recent spells of very cold, still weather when the wind didn’t generate electricity.
The government has requested that the coal-fired units at Drax power station are kept on standby for the same reasons for next winter. Drax has explained that for technical and permitting reasons they cannot extend this year’s agreement and 50 years of coal generation at Drax will come to an end.
UK energy security
A spokesperson for the department for energy security and net zero said: “Our energy supplies are safe and secure, but like last year we are exploring options to keep remaining coal-fired power stations available to provide additional back-up electricity if needed this coming winter as a contingency measure.”
In addition to using coal to boost supplies in an emergency, National Grid has been experimenting with paying customers to reduce demand during peak hours when margins are tight.
The lack of emergency coal generators on standby next winter might mean that the grid’s demand flexibility service is expanded or more heavily relied upon in order to avoid blackouts.
A wise use of subsidies?
Much of the proposed new subsidy which Drax is asking for in order to keep the plant operating beyond 2027 will be devoted to the development of biomass energy with carbon capture and storage (BECCS). One estimate puts the cost at over £30bn over the next 25 years and doubts have been expressed over whether the proposals will work in the manner suggested.
One hopes that someone in the government is very carefully scrutinising the proposals and doing a careful cost benefit analysis. It should also critically examine the claimed carbon mitigation of this ‘renewable’ energy source by assessing the harvesting, transport, drying, environmental soil and biodiversity losses of overseas production of wood pellets against claimed carbon sequestration. Such cycles should be taken into consideration when assessing where subsidies are spent and if greater climate goals could be achieved if they were targeted elsewhere.
Latest developments
In the last month, Drax shares have experienced some volatility since the government is reported to have excluded Drax from its initial Track 1 programme – part of a £20bn a year funding scheme the government announced this month for carbon capture technology. Drax shares fell by 12% on the announcement but recovered by 5% on the news that discussions with the government were continuing.