Thursday, 10 December 2020
How to calculate your carbon footprint
Following on from the Chamber’s launch of the Sustainable East Midlands campaign in November, Khaled Belgasmi (pictured), principal consultant at Nottingham-based environmental consultancy Loreus, explores how businesses can get on a greener footing by calculating their carbon footprint without breaking the bank.
As governments begin to set more ambitious targets to avoid the most damaging effects of climate change, businesses find themselves asking what can they do? What should they do?
Many will agree with the age-old maxim of “what gets measured, gets managed”, which leads us neatly to carbon footprinting.
For those that haven’t done this before, they may be thinking this entails yet more work for already busy teams and further expenditure, but what if it didn’t have to be that way?
What does a carbon footprint calculate?
A carbon footprint refers to the total greenhouse gas (GHG) emissions caused by an organisation or an individual.
But while carbon dioxide is one of the most frequently emitted GHGs – accounting for 65% of global emissions – the name if a bit of a misnomer as a carbon footprint doesn’t just cover this gas.
We often express other GHGs in terms of carbon dioxide equivalent (CO2e). Consider methane, which has a CO2e conversion factor of 28. This means that releasing 1kg of methane into the atmosphere will have the equivalent warming effect as releasing 28 kg of CO2.
These conversion factors are a key element in producing your carbon footprint and luckily, they’ve all previously been calculated, making the job much easier.
The UK Government even produces a handy summary of all the conversion factors – simply search “UK conversion factors” on the gov.uk website to find them.
Getting started with a carbon footprint in business
To keep things simple, we often encourage organisations at the start of their reporting journey to focus on just three of the main GHG sources – electricity, gas and fuel consumption.
The first thing you will need is data covering these emission sources. We call this the activity data and fortunately it’s usually easy to obtain.
Gas and electricity data can usually be found on bills, although fuel data can be a little bit harder to find.
The most accurate method is to use the litres of fuel consumed, but if an organisation doesn’t directly monitor this it can be estimated based on fuel spend using the Government’s weekly road fuel prices data.
Failing that, an organisation can use distance travelled in combination with either the vehicle type or its engine size to estimate emissions.
Calculating a carbon footprint
With this information in hand, all we now need to do is combine our activity data with the conversion factors. From the Government list, the conversion factors you’ll be interested in are:
- Natural gas (fuels tab)
- Electricity generated (UK electricity tab)
- Diesel or petrol for average biofuel blend (fuel properties tab)
- Distance travelled by vehicle type (passenger vehicles or SECR pass & delivery vehicles tabs)
To calculate the carbon footprint for each emission source, simply multiply the sum of the activity data by the relevant conversion factor.
Let’s take electricity consumption as an example. An average medium-sized UK household consumes about 12,000kWh per year.
The “electricity generated” conversion factor for 2020 is 0.23314 kg CO2e. If we multiply these two numbers together, we get 2,797.68kg CO2e released into the atmosphere from consuming 12,000 kWh of electricity. We now simply need to follow this same process for our other two emissions sources.
This article appears in the December 2020/January 2021 issue of the Chamber's Business Network magazine. To read the online edition, click here.Back