Ecodesign Parameters for Stoves

Ecodesign comes into force in 2022 and although it is a European directive, the UK government is under tremendous pressure to reduce all kinds of exhaust gas emissions, and so will not back off getting these strict new limits into place in the UK.

There are five main parameters:
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1. Thermal Efficiency: A minimum effective level of 75% net efficiency is brought in by Ecodesign, which is higher than the 72.5% currently required by Building regulations. For most manufacturers this will not be a big hurdle to get over, and it can be lowered slightly by product features such as thermostats.
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   However, there is often a trade off needed between high efficiency and low emissions, which need to be controlled much more tightly under Ecodesign, and striking this balance will be key to success overall.

2. Carbon Monoxide (CO) emissions: The average flue gas CO limit has been reduced from 1% to 0.12%, a huge reduction of nearly 90%, a real challenge for stove performance. CO is caused by incomplete combustion of the gases given off from logs during burning, and is minimised by getting the conditions and air flows right within the firebox. It is a poisonous gas, hence the desire to see emissions lowered significantly.However, it does oxidise to relatively harmless CO² in the atmosphere over time. This is one of the toughest aspects of Ecodesign to achieve.
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3. Particulate (dust) emissions: This has historically been controlled in smoke control areas of the UK by DEFRA exemption for wood burning. However, the new Ecodesign limits are much lower than the government smoke control thresholds allowed. There are three methods that can be used for this measurement; DIN+ heated filter, UK electrostatic precipitator or Full Flow Dilution Tunnel filter. But the limits for all methods are very challenging to achieve for the stove development engineer.Effectively the whole of the UK will become a smoke controlled zone for wood burning in 2022.
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4. Organic Gaseous Carbon compounds (OGC): In the same way as CO is produced by incomplete combustion, stoves not burning gases from the logs completely also release traces of those fuel gases into the atmosphere. These OGC’s are a hazard to health themselves as well as ultimately contributing to particulate dust. A limit of 120mg/m³ @ 13% Oxygen has therefore been set, which as part of the overall Ecodesign package ensures an acceptably low level of emissions results.
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5. Nitrogen Oxides (NOx): Well known as a contributor to poor air quality primarily from road transport engines, oxides of Nitrogen must be well controlled in concentrations below 200 mg/m³ @ 13% oxygen on average from a stove combustion cycle.

Overall the new Ecodesign requirements put a brand new and comprehensive set of performance limits onto the stove industry. It is certainly no walk in the park to achieve, but will lead to greatly reduced emissions from wood burners, and benefits to public health and wellbeing.

You are able to view our range of Ecodesign ready stoves in our gallery.