From black bags to green gas: how rubbish could heat our homes

It is one of the biggest energy policy challenges facing the UK: how can we heat our homes without burning natural gas? Fossil fuels currently provides 85pc of our domestic heating needs – yet if we are to meet climate change targets we must drastically curtail its use within a few decades.
According to National Grid, at least part of the answer could be found in a surprising location: your dustbin. Last week, the FTSE 100 utility giant announced a £6.3m investment in the world’s first commercially-operating plant to produce “green” gas from black bag rubbish.

The new £25m plant developed by Advanced Plasma Power (APP) in Swindon will take household and commercial waste – from dirty nappies to unrecyclable packaging – and process it into gas pure enough to be used in your existing gas boiler or hob. And, National Grid claims, enough gas could one day be made this way to heat a third of UK homes.
On a sprawling industrial estate on the outskirts of the Wiltshire town, a £5m pilot plant completed this summer with funding from energy regulator Ofgem has already proven that it is technically possible.

Using greener gas means we can keep using existing infrastructure. “It’s not disruptive in terms of the roads and our urban environments,” says Chris Train OBE, chief executive of National Grid Gas Distribution Limited. “It’s also not disruptive in the home, for customers. It allows us to use existing appliances. That’s a great advantage.”
It would clearly also be less disruptive for the business model of National Grid, which owns and operates gas transmission and four gas distribution networks. It is currently selling a 51pc stake in the latter, valuing them at more than £11bn.

The idea of getting energy from waste is not new. The UK’s rising tax on landfill rubbish means councils and businesses are willing to pay for waste to be disposed of in alternative ways. Encouraged also by renewable energy subsidies, companies like Suez, Veolia and Viridor have built or are building 55 incinerators that produce electricity by burning black bag waste. There is also an existing landfill gas industry, which extracts methane from dumps and burns it for power, and about 540 small anaerobic digestion (AD) plants, which take food and agricultural waste or sewage and use bacteria to digest them into gas. Although some then purify the gas and inject it into the grid, most just burn it for electricity.