Reports in the Guardian suggested biomass was not that efficient or great for the environment, stating efficiencies of up to 20% less than previously claimed. Rather than throw in the biomass towel, the report must be viewed as a wake-up call to the biomass sector, says Simon Holden from Euroheat: “Wood burning technology should still be viewed as a much greener and cost-effective alternative to fossil fuels, as long as the equipment, installer and fuel are of the highest quality.”
Anyone reading the DECC biomass report featured in the Guardian this January, would be forgiven for thinking wood heating was a waste of time and money. According to the DECC study, the average efficiency rate for an installed biomass boiler was just 66.5%, 20% short of the 85% efficiency rate needed for a technology to be promoted as ‘renewable’. Worrying statistics, but in my view, these are not indicative of what a biomass system should actually achieve.
Wood burning has proved hugely successful and efficient in central Europe. The problems in the UK market, which is still a very young one, come down to the quality of some boilers, the installers that fit them and the fuel they burn – get these three things right and efficiencies of over 90% are certainly achievable, placing biomass as a worthwhile carbon cutting solution.
Substandard boilers are potentially infiltrating the market (at the moment there is no equivalent to the MCS standard for units over 45kW capacity) fitted by installers who may not have the appropriate product knowledge, experience or support. In addition, end-users may be using poor quality fuel, which has not been properly seasoned and, therefore, holds too much moisture.
This autumn will see the introduction of new ‘fuel rules’ for all RHI installations in a bid to crackdown on poor quality fuel being used. Under the legislation, fuels must meet sustainability criteria in order to continue receiving RHI payments.
This will apply to all existing and new participants – even if you are already receiving RHI payments. In order to prepare for the changes, the simplest way to meet the criteria is to use sustainable fuel bought through the biomass suppliers’ list, which lists approved suppliers of wood fuels that meet RHI sustainability criteria.
Poor quality fuel can cause no end of issues with a biomass boiler, including:
- reduced performance because of poor combustion
- damaging tar deposits in the boiler and flue system
- visible and troublesome emissions from the flue
In general, moisture must be 20 per cent or less for logs; 35 per cent for woodchip to ensure optimum boiler performance. Seasoned logs will have a higher energy value, providing more heat and lower emissions. It is important that logs are split and left to dry in a well ventilated area for 12 months or more for the most efficient results. Storing logs and wood chip is ultimately the end users responsibility to make sure they are kept accordingly, but it is vital that installers fully explain the fuel to their customer, ensuring they have a handle on buying quality and maintaining quality wood fuel in large quantities.
Wood pellets are more stable and should be delivered in the correct state if purchased from a reliable source. With pellets, boiler efficiency is the sole responsibility of the installer; if commissioned correctly, a quality biomass boiler with good fuel will burn at the efficiencies of 90 per cent or more, so getting this right is key.
A sense of proportion
When it comes to the DECC report, a sense of proportion is important – a DECC spokeswoman said that the study’s sample had been small and “more work now needs to be done to fully assess the performance of biomass boiler systems and installer competency”. I for one, look forward to further research; constant review and improvement is key to helping renewables become a common fixture in our homes and businesses.
In order for the UK to move away from its reliance on fossil fuels, constructive criticism of renewable technologies and how they’re delivered is welcome and imperative. Negativity that results in consumers and installers ‘giving up’ on going green is extremely harmful however; balance and proportion is essential.
For more information about our ranges of boilers, including our range of Energy Cabins, visit www.euroheat.co.uk