UK's various waste streams could produce enough biogas to heat half the homes in the country, according to new research commissioned by National Grid.
The study, which was undertaken by Ernst & Young, concluded that biodegradable waste streams such as sewage, animal manure, food and wood could be harnessed relatively easily to generate biomethane that could be connected to the existing gas network.
It said that a UK-wide biogas network could be developed at a cost of around £10bn – a price tag the report claims is competitive with other forms of renewable energy such as wind power even before considering the higher infrastructure costs associated with connecting those other forms of renewables to the electricity grid.
Janine Freeman, head of National Grid’s Sustainable Gas Group, said that biogas had the potential to act as something of a silver bullet solution, simultaneously cutting methane and carbon emissions, boosting renewable energy capacity and providing a domestic replacement to waning North Sea gas reserves.
"Biogas has benefits on so many fronts," she argued. "It is renewable and could help to meet the target of 15 per cent of all our energy coming from renewable sources by 2020. It provides a solution for what to do with our waste with the decline in landfill capacity and it would help the UK with a secure supply of gas as North Sea sources run down."
The report also concluded that the two main approaches for producing biogas - anaerobic digestion which turns wet waste such as sewage into biomethane, and thermal gasification of dry waste such as waste wood or energy crops - are technically proven and offer a more efficient alternative to current small-scale projects to use landfill waste to generate electricity.
It argues that the only barrier to wider adoption of biogas technologies is the fact that the sector has not received the same level of government support as more established renewables sources. It also calls for an immediate overhaul of renewable heat policy.
Freeman said that biogas' "tremendous potential" would only be realised if the government commits to "a comprehensive waste policy and the right commercial incentives".
In particular, the report recommends the government develops a waste management policy to ensure each waste stream is directed to the appropriate biogas technology. It also calls for a new incentive scheme to encourage renewable gas producers to grid-inject their gas rather than generate electricity from it, as they are currently incentivised to do under the government's Renewables Obligation scheme.
A spokesman for the Department for Energy and Climate Change said that the government was already committed to recovering greater levels of energy from waste streams, adding that "further work is taking place in the context of our Renewable Energy Strategy to establish what potential might exist for biogas injection to the gas grid".
