"Billions of pounds of public money is to be spent supporting green boilers, despite evidence from the governments own experts and industry that they will do little to help the UK meet its clean energy targets.
A study by the Department of Energy and Climate Change found that biomass boilers in the non-domestic sector were around 10-20% less efficient than expected. Those boilers account for 90% of payments under the Renewable Heat Incentive (RHI), the governments flagship scheme to encourage a shift to low carbon heating.
The UK has pushed biomass boilers as a technology to help meet an EU target of getting at least 15% of its energy from renewable sources by 2020, incentivising businesses and individuals to switch to them in return for payments under the RHI.
But under-performance appears widespread in the UK biomass heat sector, the paper admits, adding that the efficiency shortfall also means emissions will be higher than laboratory test results suggest.
Just £128.9m had been paid through the RHI as of November 2014, but the final cost in public money could be over £10bn because those installing biomass boilers under the scheme receive annual payments for several years, Deccs own impact assessment shows. So far, most RHI payments appear to have been banked by wealthy landowners.
To be promoted as a renewable source of energy, the biomass boilers need to have a 85% efficiency rate for converting fuel to energy but the Decc study reveals the average efficiency rate of installed boilers was 66.5%.
The target rate may be unreachable, as the report found that the biomass heating systems surveyed can only achieve levels around 76% (on average).
Yet no field studies of biomass boiler efficiency were carried out before the RHIs introduction because Decc viewed biomass as an established and internationally successful technology.
It is concerning that government has belatedly recognised that many biomass installations will seemingly not contribute to its renewable energy targets despite billions of pounds of public money being committed via the RHI, said Simon Lomax, managing director of Kensa Group, a manufacturer of heat pump, a rival low carbon heating technology.
Policy flaws have resulted in absurdly generous tariffs for biomass installations, attracting inexperienced entrants to an immature market which does not benefit from any effective regulation, he told the Guardian.
The sole regulator for biomass boilers is the Microgeneration Certification Scheme but it only covers smaller models, below 45KW in capacity. In effect this means there are no quality standards for almost 90% of all schemes under the RHI, Deccs paper says.
The absence of any quality standard above 45kW, and of data collection and sharing is remarkable, and differs from most other countries that have seen a biomass heat sector develop successfully, it adds.
Much of the research for the design of the RHI was sub-contracted out to consultancies such as AEA and NERA and the Guardian understands that neither the figures they produced nor evidence of the renewability of biomass boilers, were scrutinised in detail by the Decc hierarchy.
Among scientists and engineers there was huge concern but policymakers just didnt understand or didnt want to understand it, a source involved in the RHI design process told the Guardian. Decc should have required us to provide suitable evidence to prove that non-domestic biomass boilers eligible for RHI funding were a renewable technology, but they didnt bother."
Chris J Dixon Nottingham UK
Chris J Dixon Nottingham UK
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