How do I calculate carbon emissions from fuel, electricity and transport?
Well its actually quite simple in many cases. Defra / DECC publish a spreadsheet detailing commonly required emissions factors.
Its updated on a frequent basis to take account of things like changes in the carbon intensity of the electrical grid, and the source of our natural gas, but otherwise most of what you need to do some basic calculations is in there.
You can find it by clicking this link and scroll down the page to find the latest version of the spreadsheet on release – Defra/DECC’s Greenhouse Gas Conversion Factors for Company Reporting