BURNING wood pellets in RHI boilers could be more damaging to the environment than coal, according to new research.
One of the environmentally friendly sources encouraged by the Renewable Heat Incentive scheme, it had been accepted that the transition from fossil fuels to biomass would reduce carbon emissions, but a report by Chatham House suggests the process could be more harmful than traditional energy sources.
Duncan Brack, author of the report Woody Biomass for Power and Heat Impacts on the Global Climate, wrote that "while some instances of biomass energy use may result in lower life-cycle emissions than fossil fuels", this was not the case in "most circumstances".
"Comparing technologies of similar ages, the use of woody biomass for energy will release higher levels of emissions than coal and considerably higher levels than gas."
The report said: "It is not valid to claim that because trees absorb carbon as they grow, the emissions from burning them can be ignored."
A spokesman for the British Department for Business, Energy and Industrial Strategy played down the report.
"All biomass power plants in the UK have to meet mandatory sustainability criteria to ensure they reduce carbon emissions. Biomass conversion projects are a useful way to convert old polluting coal power stations into lower carbon electricity sources, whilst helping us maintain energy security and keeping down bills."
The Renewable Heat Incentive Scheme was first introduced in Britain in November 2011 as a key policy in reaching enhanced renewable energy consumption targets.
It was introduced in Northern Ireland the following year, but changes to the GB policy ensured no cap was put on the lucrative subsidies resulting in a £490m overspend and scandal, which last month brought down the Stormont government and resulted in a second assembly election in less than a year.
A public inquiry into the Northern Ireland scheme is due to take place following election and will be chaired by Sir Patrick Coghlin.
