Our electricity fuel mix

As you may know, 100% of our electricity comes from renewable sources, and every year we need to let the regulator know where this comes from. Alongside every unit of renewable electricity we purchase is a snazzily named Renewable Energy Guarantee of Origin (REGO) certificate. These certificates allow Ofgem to verify the source of every supplier's electricity.

100% of Bulb's electricity is renewable, compared to 24.2% national average

Chart shows Bulb's electricity is purely renewable, compared to the UK's average electricity fuel mix which is generated with a combination of renewable (24.2%), natural gas, coal, nuclear and other.

Note: Based on Ofgem supplier submissions for 2017-18
Source: Electricity info, an independent energy information site

Generating our electricity

All Bulb members are powered by sun, wind and water. The breakdown looks like this:

  • Wind: 50%
  • Solar: 40%
  • Hydro: 9%
  • Biogen: 1%

We work with independent generators from across the country to harness the power of nature.

10% of Bulb's gas is renewable, compared to 0.5% national average

Chart shows Bulb uses 10% renewable gas (biomethane) compared to to the UK's average of about 0.5%

Note: Based on Digest of United Kingdom Energy Statistics 2017
Source: Department for Business, Energy & industrial Strategy

Our gas fuel mix

We also receive a certificate for each unit of green gas that we purchase. With gas, there are two certification schemes. We have the equally snazzily named Renewable Gas Guarantee of Origin (RGGO) certificates which are awarded by the Renewable Energy Association. On top of this, we work with Green Gas Trading Ltd who use Biomethane Certificates to do the same.

Generating our gas

10% of the gas we supply to our members is green gas, or biomethane, which is produced by a process called anaerobic digestion. We work with independent generators who use a variety of feedstocks to produce their renewable gas:

  • Purpose-grown crops: 51.8%
  • Food or farm waste: 47.8%
  • Animal waste: 0.4%

We like to think this gas is as natural as your uncle's after a plate of sprouts. And it's produced pretty much in the same way!

Calculating impact

We think it's important to help our members understand the environmental impact of choosing a renewable supplier. Here's the deal:

The average home produces 3,100 kWh of electricity and 12,000 kWh of gas each year. After grabbing a calculator, this equates to 3.2 metric tonnes of C02 being released into the atmosphere by the average home. That's quite a lot of carbon - the weight of an Asian Elephant, in fact.

At Bulb, things are a little bit different. Our electricity produces 0 kg, while our gas produces only 0.166kg of C02 per kWh. That means Bulb homes release 1.3 metric tonnes of C02 a year less than the typical UK home. Or a saving of a fully-grown Walrus.

That's a lot of numbers - and wild animals - to take in. So let's look at it in the context of trees.

A recent study found that a forest containing 150 million trees locks up 82,000 tonnes of carbon every year. That means each tree locks up 0.55 kg of carbon, equivalent to 2kg of carbon dioxide. If one tree holds 2kg of carbon dioxide, you'd need 655 trees to lock up the same amount of CO2 saved by the average Bulb home. So when you switch to Bulb, you are essentially planting 655 trees - that's some pretty spectacular gardening.