Making projections 

An emission projection consists of estimates of future trends in emissions of air pollutants, based on a set of assumptions about changes in key parameters.  For example, emission projections may require assumptions to be made regarding future levels of activity such as industrial producion, or consumption of fuels or materials, as well as how emission factors may change over time, perhaps in response to technological changes, or the introduction of additional regulation.

In order to ensure consistency between estimates of historic and projected emissions, both should be based on the same structure. Therefore, projections are made using a similar method to that used to calculate historic emissions. Historical emissions are calculated by combining an emission factor (for example, kilograms of a pollutant per million tonnes of fuel consumed) with an activity statistic (for example, million tonnes of fuel consumed).

For example:

E2009 = A2009 * EF2009

where E = emission, A = activity and EF = emission factor, for a given source, all for the year 2009.

For projected emissions:

E2020 = A2020 * EF2020

Where E = emission, A = activity and EF = emission factor, all for the year 2020.

Air Quality projections

Projected emissions for the four National Emission Ceiling Directive (NECD) pollutants and particulate matter are compiled, as required by Defra, by the NAEI team in Ricardo Energy & Environment and submitted to meet EU/international reporting requirements.  A summary of the latest forecasts was submitted in December 2011 under the NECD reporting requirements.

Emission projections are also submitted under the CLRTAP every 5 years, with the latest dataset being provided in February 2012.

The NAEI projection methodology broadly follows the methodology outlined in the EMEP/EEA Emission Inventory Guidebook 2009.

GHG projections

BEIS annually produces energy and GHG emissions projections, which are used to monitor progress towards national and international targets. The projections take into account the impact of UK policies.

Get data

For air quality pollutants, the latest UK NECD submission and CLRTAP submission are available from EIONET.

For GHGs, the latest projections can be found on the BEIS website with more detail about methodology and assumptions.

Emissions projections reports can be found on the Reports page.

Page last modified: 09 June 2016