Ecotricity, the green energy company that generates electricity from windmills, is working on producing what they call “green gas”.
It’s basically methane which is produced by bacteria carrying out anaerobic respiration as they digest organic waste in an oxygen-free environment. This process is often a problem, such as with the farming of livestock, because the excess methane is emitted into the atmosphere.
However in this case, it is used in our National Grid in place of natural gas. This is fantastic because:
a) Natural gas is a finite fossil fuel resource that takes millions of years to form and will run out
b) As we all know, we shouldn’t be burning fossil fuels anyway because of climate change
c) “Green Gas” reuses organic waste such as thrown away food, reducing our waste problem. And;
d) The process also leaves behind a useful by-product: a nutrient-rich sludge that is so full of potassium, nitrates etc that it can be used instead of artificial fertiliser. Always good.
They haven’t built any green gas mills yet, but they have already added a gas option onto their menu because they pipe it over from Holland, where they already have this technology. They’re planning to use the profit from this to set up their first gas mills in Britain.
There is actually a huge potential for this concept to have a great impact. Currently in the UK we (disgustingly) throw out 18 million tonnes of food waste. They’ve estimated that that’s enough to power 700, 000 homes! Hopefully we won’t always throw away this much food, but the process works equally well with any organic material. Waste’s from certain industries, processed sewage, or possibly a type of fast-reproducing algae would also work.
The National Grid even mentioned in a 2009 report that green gas “could meet 50% of the UK’s residential gas demand”.