7 Sep 17

Defra 2017 conversion factors: what’s changed?

smoke-stacks-web-3It’s that time of year again when Defra releases new UK Government conversion factors for company GHG reporting. We’ve looked into what’s new and have listed below the most notable changes in this year’s release.

Updates generally consist of modifications to existing methodologies, although this year also includes the addition of entirely new factors to account for overnight hotel stays, and to meet the rising use of electric vehicles.

Electricity factor

This year sees a significant reduction in the electricity conversion factor, decreasing by 15% compared to the previous 2016 value. As a result, companies may likely see reductions in their Scope 2 emissions. This will have a significant impact for many whose overall Scope 1 and Scope 2 footprints consist primarily of electricity consumption.

Emission factor for electric vehicles

Due to their increased market share and predicted growth in popularity, a number of emission factors have been assigned to plug-in electric cars and vans. Separate factors have been assigned for both battery electric and plug-in electric hybrid vehicles, so it’s important to know the distinction. These factors are designed to be used only when emissions have not already been recorded within fuel and/or electricity accounting.  

Well to Tank (WTT) data source change

Well to Tank emissions, defined as those associated with resource extraction, production and delivery have, in most cases, increased compared to the previous year’s figures. This is due to an update in methodology where data has been taken from newer, more accurate sources. As a result, for certain fuels emissions factors are considerably higher. For example for petrol the WTT emission factor has risen by over 30%.

Changes to road transport factors

The vehicle emissions methodology has been updated for average petrol and diesel biofuel blends found in public refuelling stations, to reflect the increased percentage of biofuel in the UK over the past few years. This has resulted in a small decrease in vehicle emission factors, compared to previous blends.

Improvements to the methodology for biogas and landfill factors

For biogas and landfill gas the outside of scope factors and the WTT biogas factor have been updated due to a more robust data source and an improved methodology. The resultant emission factors have decreased by 59% and 35% for landfill gas and biogas respectively.

Emission Factors for Overnight Hotel Stays

This year also sees the addition of emission factors for overnight hotel stays in various countries. These are based on estimates for an overnight stay in an average hotel on a ‘room per night’ basis. This will improve the completeness of scope 3 reporting with regards to business travel.

What to do?

The 2017 Conversion Factors should be used when calculating your footprint for calendar year 2017. Organisations should ensure that any previously calculated 2017 data is recalculated using the new conversion factors as the rise and fall of emission factors can have a significant impact on your overall emissions.

All 2017 conversion factors are available on the DEFRA website.

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Emissions factors , Environment