Green gas on the grid

As excitement over anaerobic digestion’s potential gains pace, Ecotricity, one of the UK’s renewable electricity pioneers, is going into the gas game.

The company best known for wind power is hoping to use the enormous amount of food Britons throw away each year to create a low carbon ‘biogas’ to produce either heat or electricity.

There are obvious financial incentives in doing so. Unlike the electricity generated from heat when solid waste is incinerated for landfill, every megawatt hour produced from anaerobic digestion (AD) can earn payment for its producer under the UK’s Renewables Obligation Certificate (ROC) scheme.

There are also handsome ‘gate fees’ for removing food from the waste stream. Recently, a number of British businesses and local authorities have turned to AD in response to legislative pressure to reduce the amount of rubbish they tip into landfill each year. But so far, says Ecotricity Founder Dale Vince, no one has used the process to meet the demand of UK households for a renewable source of heat.

So why wait until now? For Ecotricity, the main obstacle was how to make the sale of gas green.

“We initially considered using the proceeds to build more windmills, creating a green outcome as opposed to a green product,” Vince explains. “But then we discovered there is a way to inject biogas into the grid.” To begin with, Ecotricity will purchase the gas from other providers and connect it to the mains, with the aim of developing its own projects in the future. With a little luck, the first green gas will be running through the grid in 2010. Fortunately, unlike electricity, there is no backlog of providers queuing to link up to the gas grid, because no one else has thought of it – yet.

Vince thinks that many potential customers “would rather pay bills to us than to one of the ‘Big Six’ UK utilities”. And to make it more tempting, Ecotricity will match the price offered by British Gas.

It would take an investment of about £35 billion to meet half the UK’s gas supply through AD, according to Ecotricity. This would help to decarbonise the nation’s energy mix, and make it more self-sufficient. The North Sea is currently Britain’s largest provider of gas, but there has been a sharp rise in imports from countries such as Norway, Qatar and Algeria, from 27% in 2007, to nearly 50% in 2009. And in the future, Russia could be an increasingly important supplier – raising additional fears around energy insecurity.

The potential for ‘home-grown’ gas is, as Vince sees it, “fantastic… We can make green gas, and we can make it right here in the UK – just like we make electricity from wind.”

– Tricia Holly Davis

8 January 2010

Tricia Holly Davis