Medium Combustion Plant Directive: Are you compliant?
Category: General
Published: 18/02/2026
One year post the compliance deadline for existing plant above 5MW to comply with the Medium Combustion Plant Directive (MCPD) legislation, we ask: do you know where you stand?
The Medium Combustion Plant Directive (MCPD) is UK & EU legislation that aims to limit pollutant emissions such as nitrogen oxides (NOx) and sulphur dioxide (SO2), from combustion plants, that are known to be harmful to human health and the environment.
MCPD was drawn up to meet the regulatory gap between large combustion plants (> 50MW), covered by the Industrial Emissions Directive (IED) and smaller appliances (heaters and boilers < 1 MW) covered by the Ecodesign Directive.
It therefore applies to almost all industrial boilers, as well as engines, from 1 to 50MW. Since December 2018, all new plant falling under its remit have been required to be registered and comply with published Emission Limit Values (ELVs). And since January 2025, existing plant > 5MW should have been registered and are also required to meet their ELVs. Existing plant between 1MW & 5MW will be required to meet their ELV’s from January 2030.
However, we know from industry experience that many plant operators aren’t fully aware of the legislation and therefore don’t know where they stand in terms of being compliant. We’ve therefore summarised below:
Firstly, an operator must register and obtain a permit for the plant and then ensure that plant meets ELVs through regular monitoring and recording of plant operation. Limits apply for nitrogen oxides (NOx), sulphur dioxide (SO2) and dust.
Ongoing emission monitoring and data submission is required to confirm continued compliance. Measurements are required periodically, depending on plant size:
- Plants > 20 MW net rated thermal input: on registration, then annually.
- Plants < 20 MW net rated thermal input: on registration, then every three years.
- Measurements will only be required for pollutants which have an emission limit value laid down (NOx, SO2, dust), as well as CO for all plants.
In the UK, operators must report to regulators such as the Environment Agency, Natural Resources Wales, Department of Agriculture, Environment and Rural Affairs and Scottish Environment Protection Agency (depending on location) and provide emissions data, operational hours and any non-compliance events.
If at any time levels are above those stipulated, it is the responsibility of the operator to take measures to ensure non-compliance is kept to a minimum and rectified swiftly.
In response to the directive, we developed our
UltraNOx burners. In addition to compliance on all new plant, we’re also able to work with customers to complete
burner and plant upgrades to bring existing plant into line with the legislation – without the cost of a new installation.
Depending on capacity required we have three burner types available (S, T and E). Each has been designed, manufactured and tested in-house by our expert team. Operating on a typical boiler application, without the need for flue gas recirculation, our Ultranox burner Nox levels start from 40 mg/NM3 NOx at 3% O², leaving scope for further reduction with any future addition of FGR as may be required.
Our aftermarket team is also on hand to service, tune and monitor your plant to ensure you remain compliant.