Nearly 7.5 per cent of Ireland’s natural gas demand could be met by renewable sources such as grass and organic waste, a report commissioned by Bord Gáis has found.

The UCC and Ernst & Young report - The Future of Renewable Gas in Ireland - estimates that up to 300,000 homes each year could be heated by the renewable gas.

The process, already in use in other countries, sees organic waste and grass silage converted through the use of anaerobic digestion technology. This results in waste being broken down by bacteria without oxygen leaving methane rich biogas and a liquid and fibrous material which can be reused as fertiliser.

The biogas is then cleaned and upgraded to biomethane which can be injected directly back into the national grid.

Bord Gáis chief executive John Mullins said capturing the gas would be a “considerable step in addressing Ireland’s challenging renewable energy and waste management objectives”.

“It would help reduce our dependence on energy imports, provide jobs in the construction and operation of biomethane plants, and create new business opportunities among the farming community in rural Ireland,” he added.

The process is already well developed in other parts of Europe and farmers in Denmark and Germany have formed co-operatives to finance, build and run such renewable gas facilities.

Mr Mullins said while there are “obstacles” to making renewable gas a viable energy source in Ireland, he believes these can be overcome in a relatively short timeframe.