Large UK plants release the most NOx in the EU

A report for the European Commission has confirmed that the UK emits more nitrogen oxides (NO_x) from major power stations, steelworks, refineries and similar sites than any other EU member state.¹ Six of the largest emitters of the pollutant are situated in the UK, with power station Drax at the top of the list (see table).

The report was prepared by consultancy Entec. It covers emissions of NO_x, sulphur dioxide (SO₂) and dust from combustion plants with a thermal output greater than 50 megawatts, which are covered by the EU large combustion plant (LCP) Directive.

The report covers the Directive’s first three-yearly reporting cycle and shows that emissions of each pollutant declined between 2004 and 2006.

The largest drop was in dust emissions, which were cut by 23%. This was due to switching to cleaner fuels such as natural gas, and installing filters and electrostatic abatement. Several major dust emitters, including three Irish peat-fired power stations and an oil shale-powered Estonian station, either closed or reduced emissions significantly. Flue gas desulphurisation, used to control SO₂, also cuts dust emissions.

Total emissions of SO₂ decreased by 8.6% between 2004 and 2006, reflecting an 18% drop in the average amount of the pollutant released per plant.

Hungary achieved a remarkable 91% cut in the amount of SO₂ released per unit of energy consumed - a result of investment in desulphurisation and fuel switching in large power stations fuelled by lignite.

A recent report by the European Environment Agency found that the UK, among twelve other EU member states, is not expected to meet requirements to cut emissions of NO_x under the EU national emission ceilings Directive (ENDS Report 407, pp 56-57 ).

This poor performance is reflected in the mere 1.8% cut in NO_x emissions in the reporting period.

The average total annual emissions of NO_x from 2004 to 2006 for the UK accounted for 17.9% of the EU’s load. This is disproportionate to the UK’s consumption of 14.2% of energy used in LCPs across the EU.

The relatively poor British performance is partly explained by the Environment Agency’s continuing refusal to require power stations to fit selective catalytic reduction, which converts NO_x to nitrogen and water (ENDS Report 388, pp 26-29 ).

It is widely used in Germany, where plants with a thermal capacity of more than 500MW emit a third of the amount of NO_x produced by British plants per unit of energy consumed.

Three UK plants emit more NO_x per unit of energy consumed than any others in Europe. These are Scottish Power’s Cockenzie coal-fired power station near Edinburgh and two at BASF’s Middlesbrough chemical works.

The Cockenzie plant is ‘opted-out’ of the Directive. Rather than submitting to requirements to cut emissions, such plants are restricted to 20,000 hours’ operation between 2008 and 2015, by which time they must close.

Entec highlights problems in gathering information for the report and evaluating performance, including missing data and confusion over the correct way to compile an inventory. The report recommends improvements to the reporting process, including online reporting and guidance on completing the data-collection template.