Specified generator: apply for an environmental permit

The types of permit available, how much they cost and how to apply for your environmental permit.

Specified generator permits are standalone permits. They only cover emissions of SO2, NOx and dust to air. There are no permit conditions for water, land, energy efficiency, odour or noise.

There are 3 types of permits for specified generators, a:

  • standard rules permit (SRP) – low risk
  • simple bespoke permit – low risk
  • complex bespoke permit – high risk

Find information on what to do if your specified generator is already permitted, for example, if you have:

Before you apply

Check you have all the information you need, including the deadlines you must meet. You must have a permit in place and comply with the permit conditions by:

  • 1 January 2019 – for Tranche B specified generators
  • 1 October 2019 – for Tranche A specified generators 5 to 50MWth with emissions above 500mg/m3 which operate more than 50 hours per year

Read the guidance Specified generator: when you need a permit to check:

  • if you need to apply for a specified generator permit
  • the deadlines for all specified generators and the date you must have a permit in place

You can apply for a site permit if you’re operating:

  • an individual specified generator
  • 2 or more generators for the same purpose

Read the guidance Aggregating generators and deadlines for a specified generator site to find out how to aggregate the generators and the date you must have a permit in place.

For all types of permit you need to apply in time for the regulator to determine your application. Natural Resources Wales (NRW) have extended this date. For the latest date you must get your permit, see:


  • England, apply to the Environment Agency using these details and application forms
  • Wales, apply to NRW – use their details and application forms

Standard rules permits

To apply for a SRP you must be able to meet the rules set out in the permit. If you cannot, you must apply for a bespoke permit.

See the SRPs available for low risk Tranche B specified generators. Their suitability ranges from small base load combined heat and power systems to peaking abated diesel engines. You can only use them if your site only has Tranche B specified generators, not a mixture of As and Bs.

First, verify the standard rule permit you’re applying for. You can use the electronic application form to do this. Select a standard rule set from the ‘application’ tab and complete the ‘details’ tab with information about your generator(s). The form calculates the figures you entered to verify whether you can apply for the SRP you’ve selected.

Apply for a standard rules permit

You must provide the following information when you submit your application.

About you

You must provide:

  • information about the applicant
  • the address of the registered office

You must declare if you or any member of your organisation has:

  • any conviction of a relevant offence
  • current or past bankruptcy or insolvency proceedings against you

About your operation

You must select the SRP you’re applying for and provide the site or generator’s:

  • location – site name, address and postcode
  • the Nomenclature of Economic Activities (NACE) code for the activity

You must also provide:

  • generator name
  • location – national grid reference or latitude and longitude
  • status – Tranche A or Tranche B
  • rated thermal input (MWth)
  • type of generator – such as diesel engine, gas turbine, dual fuel engine, other engine or MCP (Medium Combustion Plant)
  • type and portion of fuels used as set out in the fuel categories in Annex 2 MCPD (Medium Combustion Plant Directive)
  • stack height
  • expected annual operating hours and average load in use
  • whether it’s in an AQMA (Air Quality Management Area) or will be deployed to an AQMA
  • the distance from places where people live or work (human receptors)

Management system

You must declare the type of management system you have and that it meets the conditions in the SRP.

Emission limit value (ELV) compliance verification

You must monitor each individual generator as specified in the permit conditions.

As part of your application you must be able to demonstrate that you can meet ELVs using M5 Monitoring of stack gas emissions from medium combustion plants and specified generators.

Charges for SRPs

These are the charges for specified generator SRPs.

Specified generators SRPs SR2018 No 1, SR2018 No 2, SR2018 No 3, SR2018 No 4, SR2018 No 5, SR2018 No 6, and SR2018 No 9:

  • application charge – £221
  • transfer charge – £169
  • surrender charge – £125
  • annual subsistence charge – £246

SR2018 No 8 mobile plant generator:

  • application charge – £221
  • transfer charge – £169
  • surrender charge – £125
  • annual subsistence charge – £273
  • deployment – no charge

Pre-application advice

In England you can request a paper form or ask for pre-application advice by:

In Wales email

Complete and submit SRP application form

Complete the electronic application form.

Email it to

If you cannot use the electronic form or you have any issues with it, please contact

Bespoke permits

You must apply for a bespoke permit if you cannot meet the conditions in a SRP. To find out if you can apply for a simple bespoke permit you’ll need to:

If the emissions screen out as ‘low risk’ you can apply for a simple bespoke permit. You’ll need to provide a completed copy of the screening tool with your application to demonstrate you’ve applied for the correct permit.

If the emissions do not screen out as ‘low risk’ you’ll need to apply for a complex bespoke permit. Complex bespoke permits require a site specific air quality modelling assessment. See the guidance on how to do detailed air quality modelling for emissions from specified generators and the information you must include in your report.

Secondary abatement to meet the ELV

You may configure several generators to exhaust all of their flue gases through a single combined stack to meet the ELV.

The regulators consider this to be an appropriate technique providing the ELV is met on that stack.

You’ll need to apply for a bespoke permit if you use this technique.

Apply for a bespoke permit

You must provide all the information required for a SRP application and you must also provide the following.

ELV compliance verification

Submit monitoring evidence that your specified generator can meet the ELV with your application for a bespoke permit.

You can demonstrate you’re meeting ELVs by using:

Energy efficiency report for specified generator 20MWth or more

If the new MCP which is also a specified generator has a total thermal rated input of 20MWth or more, you must meet Schedule 24 of the Environmental Permitting Regulations. This implements the requirements of the Energy Efficiency Directive. You must prepare and submit a report with your application on how your generator meets the requirements.

This requirement does not apply to:

  • spark ignition engines
  • existing Tranche A and Tranche B generators

Generators located in or deploying to a local authority AQMA

You must provide details of the specific AQMA.

The regulator will consult with the local authority which has responsibility for the AQMA to verify the ambient background NO2 concentration you provided.

Generators within the distance requiring a conservation assessment

For bespoke permit applications you must meet the habitats requirements as set out in the guidance screening for protected conservation areas. You may need to do detailed modelling if you cannot meet the requirements.

Charges for bespoke permits

Find charges for medium combustion plant bespoke permits in table 1.10 Environmental Permitting Charging Scheme.

If the Environment Agency needs to assess the impact of emissions to air on a habitats site they will charge you a supplementary charge. Their charge is in table 1.19.2 in the Environmental Permitting Charges Scheme.

How to apply

In England you can apply online.

Email if you cannot apply online.

Find the details on how to apply in Wales.

Get help with your bespoke application

See guidance on how to get help with your application in England.

In Wales email or call Customer Care Centre on 03000 065 3000.

After you apply

The regulator may reject your application if, for example you have:

  • not used the right forms
  • forgotten to include the fee or sent the wrong fee
  • not provided important information

Once the regulator has the information they need to start assessing your application, they will contact you and tell you that your application is ‘duly made’. You will be notified if your application is duly made within:

  • one month in England
  • 21 working days in Wales

They may still request more information if they need it to complete their assessment.

After you get your permit

If the regulator issues a specified generator permit to a mobile specified generator they will notify the local authority to which it deploys.

Once the regulators have issued your permit they will add your details to the:

See guidance on how to comply with your permit and how you’ll be regulated.

Contact your regulator

The regulators are:


Contact the Environment Agency:

General enquiries

National Customer Contact Centre
PO Box 544
S60 1BY

Monday to Friday, 8am to 6pm


Contact NRW

Published 15 July 2019
Last updated 10 September 2019 + show all updates
  1. The Environment Agency's Regulatory Position Statement: Permits for schedule 25B, Tranche B specified generators: RPS 219 for sites in England expired on 31 August 2019.
  2. The Natural Resource Wales Regulatory Decision has been extended to 31 October 2019.
  3. In England you can now apply for a bespoke permit online.
  4. First published.