Part A Processes/Installations
CHP plants with a thermal input capacity of more than 50MW are regulated as Combustion Activities (as are any CHP plants that are part of a broader industrial installation) within the Environmental Permitting (EP) Regulations that came into force on 6 April 2008. The thermal input of all plant items is aggregated for comparison with the 50MW threshold. For example, a plant that consists of three gas turbines, each with a thermal input of 18MW, will be considered as a single gas turbine plant of 54MW and will be subject to Part A regulation. Likewise, a boiler-house containing five boilers, each with a thermal input of 12MW, will be regulated as a 60MW boiler plant. A plant consisting of one gas turbine with a thermal input of 18MW, with two boilers each of 20MW thermal input, will be regulated as a 58MW combustion installation.
Defra has produced a series of guidance documents including Core Guidance which describes the general permitting and compliance requirements and guidance on the European directives which are implemented through the Environmental Permitting Regulations. The documents also include guidance on the Large Combustion Plant Directive (Article 6 covers CHP permitting requirements).
In addition to Defra's guidance, the EA have produced guidance on the parts of the regulations that they are responsible for (Part A(1) activities and Waste Operations). Their guidance includes Technical Guidance Notes, risk assessment tool, application form and form guidance.
These documents are intended as guidance to the regulators and to plant operators in general, and provide a basis for the conditions and environmental performance that will be required under a permit from the EA/SEPA.
One of the key legislative issues that affects authorisations is the Air Quality Strategy and the need for the UK to achieve its targets on Ambient Air Quality, so plants located in areas with a risk of poor air quality may be expected to achieve tighter emission limits.