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06 Sep 2013, 12:10 Robin Webster The government hasn’t turned away from plans to generate increasing amounts of electricity by burning biomass, despite introducing new restrictions to its subsidies. Burning plants, trees and crops in power stations instead of coal or gas is an important part of the government’s plans to switch to greener sources of electricity. In 2011, it suggested the sector could grow by nine per cent a year, accounting for about one-fifth of the total amount of renewable power the country sources by 2020. Controversy recently blew up after NGOs claimed that far from being a renewable source of power, burning trees in power stations could even more carbon-polluting than coal. The renewables industry hit back, accusing green groups of ” scaremongering ” on the issue. But then government put in place new limits on subsidies for biomass power stations. It also introduced   sustainability criteria for biomass, under which biomass burnt in power stations should emit 72 per cent fewer greenhouse gas emissions than the grid average by the end of the decade. So does this mean the government’s lost enthusiasm for bioenergy? Not really. Subsidies still good First up, the subsidy cut is pretty limited in scale. Specifically, the government has set a 400 megawatt cap on the amount of new biomass plants it is prepared to subsidise under its old subsidy system, known as Renewables Obligation Certificates . Under its new system – Contracts for Difference – it says it won’t subsidise new-build biomass at all, unless it also puts in place a combined heat and power system (CHP) as well. But the subsidy cut doesn’t apply to coal-fired power stations – like Drax power station , Eggborough , Ironbridge or Alcan Lynemouth – that want to convert to burn biomass instead. The government has promised it will keep subsidising these power stations up until 2027. Figures from a Department for Energy and Climate Change (DECC) report indicate converted power stations could be burning between 15 and 25 million tonnes of biomass by 2017. Industry group Back Biomass told us in May it expects Drax power station to burn seven million tonnes of biomass and Eggborough around eight million every year. The comparable figure for the UK’s annual wood harvest is five million tonnes , so that would mean burning a lot of wood.   Back Biomass told Carbon Brief this week: “The biomass industry has enjoyed a strong underpinning in legislation, regulatory measures and Government support. DECC has reassured stakeholders recently that it remains committed to biomass in the energy mix.” It says the government’s promise to continue to subsidise biomass conversions has given “much needed confidence” to investors in the sector. DECC tells us it will be publishing a new renewable energy roadmap this Autumn, which will include revised projections for how much energy it expects to get from different sources. Maybe it will contain surprises, but there seem to be few grounds for assuming a big reduction in biomass power.   Greenhouse gas emissions and the mystery of the missing calculator If biomass is going to retain a significant stake in the UK energy mix, questions will continue about whether or not it can be counted as a low carbon fuel source. Some research indicates that because it takes such a long time for trees to grow back, burning whole trees could release even more greenhouse gas emissions than coal.   A draft ‘carbon calculator’, developed by DECC and leaked by NGOs in March , appeared to agree. The preliminary results suggested biomass generation produces more emissions than burning coal in five out of the twelve scenarios tested. The NGOs were criticised for leaking the calculator. Back Biomass pointed out that the calculator was still in development phase and would change. And DECC’s chief scientist, David Mackay, wrote to green groups to protest at the release of the findings before they were finalised. Meanwhile, the calculator’s official launch has been delayed. What’s more, according to the NGOs, the government’s new sustainability standards fail to take the findings of DECC’s calculator into account – because they don’t factor in the carbon emissions associated with burning trees. Kenneth Richter from environmental campaign group Friends of the Earth says: “The government’s sustainability criteria are near-meaningless as they ignore the most critical issue: The carbon methodology fails to distinguish between those biomass pathways that result in real emission savings and those that result in higher emissions than fossil fuels as DECC’s own research has shown.” The government says it won’t make any further changes to its carbon accounting methodology until 2027. So if there are any problems with it, it’s going to be a while before they get changed. We put these points to DECC, but didn’t get a response. How much biomass will the UK burn in the future? Arguments over burning biomass and greenhouse gas emissions are complicated . The analysis that biomass could be ‘more polluting than coal’ is based on the assumption that whole trees are burnt in power stations. But the biomass industry argues this is an unrealistic option . It says by-products from forestry like sawdust, bark and thinnings will be used instead, which would be much less polluting. Campaigners disagree. Last week NGOs in the USA released a report arguing demand for biomass in Europe is driving deforestation in North Carolina. Whatever the truth, it appears we’re still planning to burn quite a lot of biomass – a good deal of it wood – in power stations over the next few years. And quite what that means for greenhouse gas emissions remains an important, and unanswered, question. Continue reading →