How Our Green Gas Works

Step one - Take some organic waste

To make Green Gas we need a source of organic material, like for example waste food.

In the UK, we have about 18m tonnes of that ‘available’ each year. It’s a good place to start we think. With that we could make enough Green Gas to supply over 700,000 homes.

This waste food needs collecting. Several councils in the UK have experimented with segregated waste collection, whereby people separate their food waste and put it out in a different bin, for the bin men to collect. This is an ideal way to harness waste food that would otherwise go to landfill or incineration.

And segregated waste collection has another benefit. It seems (early trials have shown)  that once we become more aware of how much food we waste (because it’s more visible to us) we start to waste less. 

And instead of having a weekly collection for the waste that can't be recycled and a two weekly recyclables collection – it’s likely that the situation will invert – every week there’s a collection of food waste and the residual waste becomes so small it gets collected every two weeks.

Sounds like progress on the waste front. 

Step two - Take it to a Green Gasmill

Once it’s been collected, the food waste goes to a Green Gasmill – a place that makes Green Gas, by a process known as Anaerobic Digestion.

In a Green Gasmill organisms such as bacteria feed on the food waste (or other organic material), in the absence of air. They break down the organic matter, in the process producing gasses like methane.

And there’s leftovers – a sludge that’s rich in nitrogen, phosphorous and potassium - an excellent natural fertiliser.

New ways of creating Green Gas are being researched all the time. Next-generation technologies, such as special strains of naturally occurring, fast reproducing algae, could be a potentially endless source of Green Gas in the future.

Step Three - Into the National gas grid

Once the gas has been made, it’s cleaned up (mostly that means having some CO₂ removed) and pumped directly into the National gas grid.

From there it can be used to cook and heat with, in exactly the same way as we do with fossil gas.

It’s really that simple. Of course there are technical and commercial issues to deal with. But it’s not rocket science. 

We can make our own gas and we can put it into the grid, to be used alongside fossil gas and one day instead of it.

Greening gas now…

We’ve not built one of our Green Gasmills yet and while we’re working on that we’re sourcing Green Gas from elsewhere, actually from Holland. Holland is connected to the UK gas grid, and has some infrastructure for making Green Gas already – using a waste source from sugar making (from sugar beets). By buying Green Gas in Holland we're adding some Green Gas to our mix now, while we work on building our own Green Gasmills in Britain. Our aim is to get to 10% this way, while we do what it takes to get our first Gasmill up and running.