We provide a complete product package inclusive of advice, design, manufacture, installation, commissioning, service, warranty and whole lifecycle management.

Our solutions are built on diverse and relevant experience and high levels of expertise.

01223 872933

Does the MCPD legislation apply to me?

For many clients the journey starts by considering their environmental objectives and whether they have a legal obligation to reduce NOx emissions.

We can help you establish how the legislation including the Medium Combustion Plant Directive and the Environmental Permitting Regulations for England & Wales relate to your new or existing plant and provide advice on the way forward.

The MCPD criteria consider factors including capacity, function and annual usage. The following are generally within the scope:  


Does the MCPD legislation apply to me?

Criteria One

Combustion plants with a rated thermal input of ≥ 1 MW and < 50 MW (‘medium combustion plants’) irrespective of the fuel type.

Criteria Two

Combinations formed by new MCPs where waste gases are discharged through a common stack or could be discharged from a common stack in the opinion of the Competent Authority.

Whereas the following generally fall outside the MCPD scope:

Combustion Plants covered by Chapter III or IV of Directive 2010/75/EU
Combustion Plants covered by Directive 96/68/EC
Any technical apparatus used in the propulsion of a vehicle, ship or aircraft
Gas turbines and gas and diesel engines when used on offshore platforms
Research, development or testing of MCPs


Our systems are specifically designed and manufactured to cope with the harsh thermodynamic loading of continuous operation at fixed speed and the high impact transient loading associated with power generation applications.

Before we specify a NOxProtekt SCR system we model its effects on the existing plant, including calculation of fluid flow dynamics and pressure drop effects to optimise the equipment for the specific application. To achieve this with confidence requires a design team with experience and expertise in power generation engine applications.

It is crucial to get these aspects right at the design stage because of the risks involved. Incorrectly sized SCR equipment could force back pressure on a high compression ignition engine interrupting performance, or in an extreme case cause engine failure and possible explosion.

How it works

Our main aim is to convert polluting NOx emissions to harmless nitrogen and water vapour.

The SCR process filters combustion emissions converting nitric oxide, nitrogen dioxide and ammonia to harmless nitrogen and water vapour.

To achieve this requires consideration of many factors and design of a system comprising 7 key elements:

Typical NOxProtekt SCR system.

Each application is different, so we design bespoke solutions, particularly as the catalyst sizing process depends on the specific characteristics of the power generator.


To optimise an SCR design we have to consider 11 parameters:

Environmental legislation

Engine power

Exhaust gas flowrate

Exhaust gas temperature

Exhaust gas pressure

Exhaust emissions

Type of engine fuel

Available back pressure

Noise attenuation

Space restrictions

Engine utilisation

Each of these parameters influence aspects of the SCR design including:

SCR catalyst

active ingredients, size and shape, cell density, material of construction

Venturi mixer

size, shape
& orientation

Urea injection point

type, size, shape & orientation  

Urea Injection system

purge fluid/as & times and control  


All elements of our systems are weatherproof and suitable for external use, including the control panels.


With manufacturing taking place off-site the delivery and installation of our containerised SCR systems is quick and efficient. Disruption is kept to a minimum because we connect to the exhaust system of your existing plant and generally require only minor modifications.

We’ve installed systems throughout the UK and our engineers embrace the challenge of working safely and efficiently in challenging locations including:

Based on working for many years in highly regulated industries we have a well-established workflow for commissioning and validation before handover.

Working at height to access rooftop plant
Restricted headroom such as basements
WIMES sites (Water Industry Mechanical & Electrical Specifications)
Secure and sensitive sites including police and hospital premises
Remote locations

 Based on working for many years in highly regulated industries we have a well-established workflow for commissioning and validation before handover.

Because we build modular systems off-site and make very few modifications to your existing plant the installation process is quick and causes minimal disruption or down-time.

All systems undergo a rigorous commissioning process before handover.



Our systems do not require a lot of maintenance, but we are on hand to check or modify the equipment if needed. We provide a range of warranty options and ongoing supply of spare parts.

The MCPD legislation requires monitoring. Periodic (short term) measurements are required at least every 3 years for plants with a rated thermal input of 1 – 20 MW, and every year for plants with a rated thermal input greater than 20 MWs. The MCPD states that sampling and analysis of polluting substances and measurements of process parameters, as well as any alternatives must be based on methods enabling reliable, representative and comparable results. Talk to us about installing automated systems to report on performance and provide timely warning of any issues.

If there is a future need for repair or modifications, you can be sure that we will be here to help.

The NOxProtekt difference

Unique technology, optimised for your site

Minimal interference with your plant and to the operation of your business

We understand the risks and provide compliant solutions that will not impact your plant

Get Started

For a free quote regarding the custom systems we build or any extra information on the services we offer, please feel free to contact us

01223 872933

Newton Hall, Town St, Newton, Cambridge CB22 7ZE

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AMPS Member
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