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Bulb's green gas: where it comes from and the impact it's having

A photo of a green gas production site

What is green gas? Good question. Also known as ‘biomethane,’ it’s gas that you can use to heat your home or cook with, in the same way as you would with ‘non-green’ gas. The difference is that it’s kinder to the planet.

Green gas is made through a process called anaerobic digestion. This uses bacteria to break down organic materials – like food or farm waste – to release biogas. The biogas is purified and turned into biomethane, which is injected into the gas grid. Once in the grid, it’s piped into homes up and down the UK.

What makes gas green?

There are two things that give biomethane its ‘green’ credentials. The first is that it comes from a renewable source, like food and farm waste. By contrast ’non-green gas’ is formed when decomposing plant and animal matter is exposed to intense heat and pressure over millions of years. Described as ‘fossil fuel’, this is a natural process, but not easily renewable in our own lifetimes. There’s a limited amount of fossil fuel, and we’re using it up, fast.

The second thing is that burning biomethane is carbon neutral.  

Burning any gas to heat our homes releases emissions. When we extract and burn gas from fossil fuels, we’re reintroducing carbon dioxide (CO2) into the atmosphere that has been locked away for millions of years. It’s this increase in CO2 levels that causes man-made climate change.

But biomethane is produced from organic materials that absorbed carbon dioxide while they grew. So when it’s burned, it only releases that same amount of carbon dioxide. Since it doesn’t add more CO2 to the earth’s atmosphere, it’s a carbon neutral option.

A photo illustrating the key parts of Huggin Farm green gas plant
Green gas is made by decomposing food and farm waste in large digesters. This biogas is then purified before entering the UK gas grid, where it’s used to heat your homes. Any waste from the process is put back on the land as organic fertiliser.

Our gas mix for 2017-2018

Bulb is the UK’s largest green energy supplier. We supply 100% renewable electricity to over 800,000 homes in the UK. We also supply 10% green gas, which is 30 times higher than the national average.

The proportion of green gas in relation to electricity might seem surprising to some, but the simple fact is, there’s just less green gas produced in the UK than renewable electricity. Despite this, we’re continuing to do whatever we can to promote green gas and provide as much as possible to our members.

Unlike electricity, Ofgem doesn’t require suppliers to disclose their renewable gas mix, but we believe our members should know exactly where their energy comes from, and we wouldn’t be surprised if customers of other suppliers wanted the same.

In the last year, of the 10% green gas we supplied to our members, almost 100% came from purpose-grown crops or food and farm waste. Just 0.4% came from animal waste. We bought around 15% of the UK green gas market, and we’re currently on track to buy more than 40% of it this year, depending on how Bulb, and the market, grows in the next few months.

We work with generators across the UK, and we have 3-year agreements with over half of our green gas sites. Considering these are relatively new generators, we’re excited to be able to help provide them with price certainty and longevity. We hope that by showing there’s such a huge demand for renewable gas in the UK, more green gas plants will be built.

A photo of Icknield Farm
Icknield Farm: our first green gas partners.

Where do we go from here?

We’re currently the largest supplier of green gas in the UK, only 3 years after becoming an energy supplier. We think this is pretty impressive, especially as there was no renewable gas in the UK grid six years ago.

But we’re not stopping there. We’re looking at opportunities that can help us supply much more than 10% green gas to our members, so watch this space.

You’re having the biggest impact

We’re proud to be doing our part in increasing demand for green gas generation in the UK. But we genuinely couldn’t do it without every one of our members. As our member count grows we’re buying more energy. The more we buy, the more we can help give generators price certainty and longevity. And as this demand increases, more green gas plants will crop up.

So think of it this way – we’ve made a great start, but the more people you refer to Bulb, the bigger the demand for renewable gas. And on top of that, we’ll give you and your friend £50.

Get to know our generators

At Bulb, we think it’s really important that you know where your energy comes from. You can get to know all Bulb Generators here.