New GHG conversion factors mean changes to baselines

Organisations using Defra's greenhouse-gas (GHG) conversion factors to calculate their emissions may have to adjust their baseline figures following an overhaul of the guidelines

The environment department has published revised GHG conversion factors and new guidance to help firms to calculate and report their scope 1, 2 and 3 emissions, ahead of the introduction of mandatory GHG reporting in October.

Defra instigated a review of the GHG conversion factors in late 2012 with the aim of simplifying the process. The revised guidelines include removing the five-year rolling grid average used to calculate emissions from electricity generation.

The conversion factors now only use a one-year grid average, and organisations that have previously used the five-year rolling average must recalucate their baseline figures.

“Failure to ‘rebaseline’ will result in a large drop in emissions for the new reporting year… this will result in false interpretation,” states guidance outlining the main changes.

“Organisations should revisit their historic electricity data, remove the old five-year average conversion factor and replace it with the newly stated one-year average conversion factor.

“Organisations should restate their carbon footprint across each relevant historic reporting period, including the base year, to compensate for the change.”

Other changes include the deletion of tables relating to calculating emissions from electricity consumption. Previously tables 3c and 10c in the guidelines had provided values for emissions from electricity generation (scope 2) and from losses through the transmission and distribution of electricity (scope 3).

Following feedback that these figures were being misinterpreted and reported only under scope 2 emissions, these have been removed.

The environment department has also decided it will no longer update previously published conversion factors. In the past, factors in the “historic time series” (such as electricity generation) changed each year and organisations were forced to retrospectively recalculate their figures accordingly.

“The only reason for users to make historic updates to conversion factors in the reporting after the 2013 convention comes into force will be to correct errors,” confirmed Defra.

Another material change is the removal of “all scopes” factors. According to Defra there was “significant confusion” over these factors and, with many firms reporting their emissions in relation to whether they are scope 1, 2 or 3, the inclusion of such factors had “jeopardised transparency”.

Going forward the factors will be specifically categorised as scope 1, 2 or 3, which will also result in some firms having to update their historical reports to enable year-on-year comparisons.

The revised factors are now available online through ukconversionfactorscarbonsmart.co.uk, which has been designed to help make it easier for practitioners to find the most relevant conversion factors for their organisation.

The aim of the streamlining and simplification project is to make the selection of conversion factors the “least time consuming part of the reporting journey”, states Defra.

Carbon Smart, the consultancy that revised the conversion factors on behalf of Defra acknowledges that in the short term the changes will mean more work for firms, but maintains that eventually the changes will benefit businesses.

The firm urged all organisations using the conversion factors to make sure they understood how the changes would affect their GHG reporting moving forward.


What do you think of the new conversion factors? Are they easier to use? Post your comments below.

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