Greenhouse gas conversion factors are used to determine the carbon dioxide emissions caused by the use of energy. In order to convert energy consumed in kWh to kg of carbon dioxide, the energy use should be multiplied by a conversion factor.
For example the conversion factor for natural gas is 0.185kgCO2/kWh, so the use of 1,000 kWh of gas is responsible for the production of 0.185 x 1000 = 185kg CO2.
Greenhouse gas conversion factors are published by Defra to supplement their Environmental Reporting Guidelines.
The most useful factors are contained in CTL018 - Energy and Carbon Conversions fact sheet and are summarised below:
| |
Conversion to CO2 (gross CV basis) |
|
| Energy source |
Units Kg CO2 per unit |
|
| Grid electricity |
kWh 0.537 |
|
| Natural gas |
kWh 0.185 |
|
| LPG |
kWh 0.214 |
|
|
litres 1.495 |
|
| Gas oil |
kWh 0.252 |
|
|
litres 2.674 |
|
| Fuel oil |
kWh 0.268 |
|
|
litres 3.179 |
|
| Burning oil |
kWh 0.245 |
|
| |
litres 2.518 |
|
| Diesel |
kWh 0.250 |
|
|
litres 2.630 |
|
| Petrol |
kWh 0.240 |
|
|
litres 2.315 |
|
| Industrial coal |
kWh 0.330 |
|
|
tonnes 2,457 |
|
| Wood pellets |
kWh 0.025 |
|
|
tonnes 132 |
|
A more comprehensive list of 2008 conversion factors can be found on the Defra website.
Example
To convert from litres of fuel oil to kgCO2 emissions multiply by 3.179, so for example:
200 litres fuel oil = 200 x 3.179 = 635.8 kgCO2
Note: Carbon emissions are usually quoted in kg CO2/kWh.
If you wish to convert the carbon dioxide factors into
carbon equivalents (ie kgC/kWh), multiply the figure
by 12 and divide by 44.
|