How we calculate our carbon impact

By being with Bulb, you significantly shrink your carbon footprint. The carbon impact of the average home is lowered by 3.2 tonnes of CO2 a year.

How homes with Bulb lower their carbon impact by 3.2 tonnes of CO2 a year

To calculate this, we compare the carbon emissions you have for your energy use with Bulb, compared to what they’d be if you were with a typical supplier. In 2020, the average Bulb home used 4,491 kWh of electricity and 11,607 kWh of gas. We use these figures to make the comparison.

With Bulb, annual CO2 emissions for the energy you use at home are zero. This is because we provide 100% renewable electricity and 100% carbon neutral gas. So, homes with Bulb emit 0.00 kg of CO2 per kWh of electricity and 0.00 kg of CO2 per kWh of gas. 

With an average supplier, annual CO2 emissions for the energy you use at home would be around 3.2 tonnes per year. The UK government report on the carbon emissions for homes on the average energy fuel mix. In 2020, these figures were 0.233 kg of CO2 per kWh of electricity and 0.184 kg per kWh of gas. Over the course of a year, a Bulb home on the average UK fuel mix would emit 1.1 tonnes of CO2 from electricity usage and 2.1 tonnes of CO2 from gas usage.

How we help you make sense of this impact

3.2 tonnes of carbon is a lot. But it's hard to imagine. What does that much carbon look like? We like to put it in context to make things clearer. We might talk about 3.2 tonnes as a quarter of your total personal carbon emissions. Or we might compare this figure to something you’re more familiar with. For example, an Orca whale also weighs around 3.2 tonnes. 

According to a study by the Forestry Commission, it would take 1,590 trees to absorb that much carbon in a year. Kielder Forest’s 150 million trees lock up 82,000 tonnes of carbon every year. Each tree is locking up roughly 0.546 kg of carbon per year – equivalent to 2 kg of CO2. So, if one tree locks up 2 kg of CO2 per year, you'd need 1,590 trees to absorb 3.2 tonnes of it.

We find that comparing your carbon impact to understandable things like animals and trees helps you to make sense of it. We’ll continue to explore new ways to do that.

Was this article helpful?