The MCPD and how it affects commercial boilers

New legislation came into force in 2018 covering emissions from medium combustion plants, which commercial boilers also belong to.

We answer your questions on the MCPD in reference to commercial boilers in the article below.

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1. What is the Medium Combustion Plant Directive (MCPD)?
2. Why was the MCPD introduced?
3. What is a ‘medium combustion plant’ (MCP) and what does the MCPD cover?
4. If I install two or more boilers which will provide more than 1MW as total output, do they have to comply with MCPD?
5. When did the MCPD come into force/when does it apply from?
6. What are other significant dates in relation to the MCPD?
7. What are the dates and NOx emission limit values as set by the MCPD?
8. Does the MCPD affect new installations?
9. Who is responsible for the registration of the plant and reporting on and adhering to the emission limits as set by the MCPD?
10. Does the operator have to register or apply for a permit for my existing boilers that are over 1MW?
11. When does an existing plant become a new plant?
12. Are there any exemptions from the MCPD?
13. Where can I find more information on where to apply for a suitable permit in the UK?
14. Where can I find the original legislation?

1.    What is the Medium Combustion Plant Directive (MCPD)?  

The MCPD is legislation which regulates emissions of

• nitrogen oxides NO_x,
• sulphur dioxide (SO₂) and
• dust into the air

from medium combustion plants which also includes commercial boilers. 
It specifies the level of ongoing monitoring to ensure continued compliance for any plant covered by this directive.

2. Why was the MCPD introduced?

The MCPD aims at reducing air pollution to protect citizens from the harmful effects of these emissions on human health.

3. What is a ‘medium combustion plant’ (MCP) and what does the MCPD cover?

A Medium Combustion Plant is an individual combustion plant with a rated thermal input greater than or equal to 1MW but less than 50MW.

4. If I install two or more boilers which will provide more than 1MWth as total input, do they have to comply with MCPD?

The MCPD regulates individual combustion plants with a thermal input greater than or equal to 1MW.

Individual plants with an input lower than 1MWth are covered by the Energy related Products Directive and Building Regulations.

5.    When did the MCPD come into force/when does it apply from?

• 20th December 2018: emission limit values for new medium combustion plants have been enforced and need to be complied with
• Registration/permission is required from the relevant authority before the plant can be put to service
• Any plant where it cannot be proven that it was installed and operational before that date will be regarded as new plant and immediately subject to the requirements of MCPD

6.    What are other significant dates in relation to the MCPD?

Plants above 5MW

Plants 1MW to 5MW

7.    What are the dates and NO_x emission limit values as set by the MCPD?

From 20th December 2018 (new medium combustion plants ≥ 1MW but less than 5MW):

• Natural gas: 100 mg/Nm³
• Oil: 200 mg/Nm³

From 1st January 2025 (existing^*  medium combustion plants > 5MW thermal input):

• Natural gas and oil: 200 mg/Nm³

From 1st January 2030 (existing medium combustion plants ≥ 1MW but less than 5 MW thermal input)

• Natural gas: 250 mg/Nm³
• Oil: 200 mg/Nm³

Note: Compared to NO_x emission values according to the Ecodesign Directive which is defined in BS EN 15502 (weighted gross calorific value, dry air free (0% O₂), the ELVs for the MCPD are measured at a temperature of 273.15 K, a pressure of 101,3 kPa and a standardised O₂ content of 3%.

_{* Combustion plant put into operation before 20 December 2018/permit granted before 19 December 2017 provided that the plant is put into operation no later than 20 December 2018}

8.    Does the MCPD affect new installations? 

• All new installations require a permit or registration
• In addition to emission limit values (ELVs) specified in MCPD, the local governments, permitting authorities or regulators may impose other requirements on new installations, e.g. the position of the plant or the discharge of the combustion products which specifiers, installers and operators should be aware of

9.    Who is responsible for the registration of the plant and reporting on and adhering to the emission limits as set by the MCPD?

The responsibility to apply for a permit to operate lies with the operator of the plant.

10.    Does the operator have to register or apply for a permit for my existing boilers that are over 1MW?

• All MCPs, existing and new, will have to be registered/permitted
• Compliance dates for existing plants depend on their size and which agency they are covered by
• Applications for permits for new plant should be made at least 12 weeks before operation (England / Wales) or at least 4 months before operation (Scotland)
• Permits are issued in the England and Wales under Environment Agency Standard Rule No.7, or in Scotland or Northern Ireland under Part B of the Pollution Prevention and Control Regulations

11.    When does an existing plant become a new plant?

• Any existing MCP that is altered or repaired such that the ELVs for that MCP will change, shall be considered new (see Art 9) i.e. if an existing boiler is running on heavy oil and it is converted to run on natural gas, this will be a new MCP
• An existing MCP can become a new MCP if it is substantially^** refurbished 

^{**A Substantial Refurbishment is one whose costs exceed 50% of the investment cost for a new comparable MCP unit. Ref: Energy Efficiency Directive Art.14.}

12.    Are there any exemptions from the MCPD?

The following are extracts from the UK Statutory Instrument (2018 No. 110). The Scottish Statutory Instrument (2017 No. 446) and the Statutory Rule of Northern Ireland (2013 No. 160) used to enact the directive are largely the same but specifiers, installers and operators are advised to check the regulations and permits that apply in their local area.

Limited Operating Hours – existing MCP

1. An existing medium combustion plant which operates for no more than 500 operating hours per year, as a rolling average over a period of five years, is not required to comply with the emission limit values set out in Tables 1, 2, and 3 of Part 1 of Annex II, provided that the operator has signed a declaration in accordance with paragraph 7 of Annex I.
2. An existing medium combustion plant is not required to comply with the emission limit values set out in Tables 1, 2, and 3 of Part 1 of Annex II where it operates for no more than 1,000 operating hours per year, as a rolling average over a period of five years to 
   1. provide backup power production in islands connected to an electricity transmission system or distribution system, in the event of an interruption of the main power supply to an island; or
   2. produce heat in cases of exceptionally cold weather events

• provided that the operator has signed a declaration in accordance with paragraph 7 of Annex I

Limited Operating Hours – new MCP

1. A new medium combustion plant which operates for no more than 500 operating hours per year, as a rolling average over a period of three years, is not required to comply with the emission limit values set out in Part 2 of Annex II, provided that the operator has signed a declaration in accordance with paragraph 7 of Annex I.

13.    Where can I find more information on where to apply for a suitable permit in the UK?

England:

• https://www.gov.uk/government/collections/standard-rules-environmental-permitting
• https://www.gov.uk/government/publications/sr2018-no-7-new-low-risk-stationary-medium-combustionplant-1-20mwth-in-operation-after-20122018

Northern Ireland:

• https://www.daera-ni.gov.uk/articles/medium-combustion-plant-directive-and-specified-generators

Scotland:

• https://www.sepa.org.uk/regulations/pollution-prevention-and-control/medium-combustion-plant/
• https://www.sepa.org.uk/regulations/pollution-prevention-and-control/ppc-part-b-activities/

Wales:

• https://naturalresources.wales/permits-and-permissions/medium-combustion-plant-and-specifiedgenerator-activities/?lang=en

14.    Where can I find the original legislation?

On the website of the European Commission.

Do you have any more questions that are not covered on this page? Get in touch with us, we’re happy to look into this for you.

Disclaimer: Every effort has been made to ensure the details are accurate. Hamworthy Heating does not, however, guarantee the accuracy or completeness of any information nor does it accept liability for any errors or omissions in the information. While we endeavour to keep our website up to date, legislation is subject to regular changes – please refer to linked government websites for recent information.