Version information

Version 4

The current version of the calculator (Version 4) dates from January 2019 with changes to incorporate the latest emission factors and other information.

The main changes from Version 3 to Version 4 are as follows.

1. Electricity:

The CO2 emission factor was changed to 0.309 kge / kWh from 0.527 kg / kWh.
CO2 emissions have fallen because of the switch from coal to gas in UK electricity generation. (Jan 2019)

An option for accommodation in a student hall of residence was added, with a value of 2000kWh electricity use per person per year (Feb 2020).

2. Gas:

An option for accommodation in a student hall of residence was added, with a value of 5000kWh gas use per person per year (Feb 2020).

3. Typical car fuel use figures

Figures were updated from the DEFRA car emissions factors used in Version 3:
SizeEngine size (litres)mpggCO2 per mile*
small car< 1.5 37 390
medium car1.5 - 2.0 33 430
large car> 2.0 24 600
*calculated from mpg and CO2 emissions of 14.3 kg per gallon

to

measured values taken from the Which magazine:
SizeAverage mpggCO2 per mile*
Small, medium, large, city and estate cars52280
MPVs and small & medium SUVs46310
Sports cars and large SUVs35410
*calculated from mpg and CO2 emissions of 14.3 kg per gallon
(Jan 2020)


Version 3

The previous version of the calculator was Version 3, published in March 2008. It is still available at https://www.carbonindependent.org/index_v3.html to enable a like-for-like comparison with previous carbon footprint estimates made using version 3.

The main changes in version 3 from version 2 were:

The factors unchanged were:

Updates were made in December 2013 to include coal, wood, bottled gas, and newer "green" electricity tariffs.

Cosmetic changes were made in February 2015, together with a change from .htm to .html filetype, but there were no changes to the underlying calculations.

Version 2

This was first published in August 2007 - and was superseded in March 2008.

Version 1

This was first published in February 2007 - and was superseded in August 2007.



First published: 2008
Last updated: 28 Nov 2022