CONSTRUCTION work has been completed on a ground-breaking “green” energy plant at brewing and leisure retail company Adnams’ distribution site outside Southwold.

The anaerobic digestion (AD) unit will be the first of its kind in the UK to use by-products from the brewing process and local food waste as a renewable source of gas for injection into the national gas grid as well as providing gas for use as a vehicle fuel.

Adnams Bio Energy Ltd, a subsidiary of the Cambridge-based Bio Group, to which the Adnams has licensed its name, will start supplying gas to the grid once commissioning work is completed later this summer, in a partnership with British Gas and the National Grid.

The plant will generate up to 4.8million kilowatt-hours of energy a year, enough to heat 235 family homes for a year or run an average family car for four million miles.

In practice, around 60% of the output will be supplied to the National Grid, with the remainder being used to power the Adnams brewery and run the company’s fleet of lorries.

The plant consists of three “digesters” ? sealed vessels in which naturally-occurring bacteria act without oxygen to break down organic waste. The result is the production of biomethane, plus a liquid organic fertiliser.

Biomethane is very similar to natural gas and, once upgraded to grid specification, can be injected into the gas network for end use by customers.

Besides representing a renewable source of energy, so helping to reduce carbon emissions, the plant will also prevent the release into the atmosphere of methane ? another contributor to global warming ? which would result were the waste to be sent to landfill.

Under an agreement with British Gas parent company Centrica, Adnams Bio Energy is also installing solar thermal panels and photo voltaic cells on the site, effectively creating a mini “energy park” and ensuring that all of the site, including the Adnams distribution centre, will be using renewable energy generated on-site with some surplus energy available for export.

The �2.75million project has been supported by funding from Royal Bank of Scotland and grants from the European Regional Development Fund, the East of England Development Agency and the Department of Energy and Climate Change.

Steve Sharratt, chief executive of Bio Group, which has experience in the design and construction of renewable energy processing plants across the UK, said the Southwold facility represented the first stage in a national roll out of AD plants.

“We use innovative, low carbon building techniques to produce energy through a completely organic and natural process; nothing is wasted,” he added.

Adnams chief executive Andy Wood said: “We are delighted that Adnams Bio Energy is located on the site of our eco-distribution centre.

“For a number of years now, Adnams has been investing in ways to reduce our impact on the environment. The reality of being able to convert our own brewing waste and local food waste to power Adnams’ brewery and vehicles, as well as the wider community is very exciting.”

Mr Wood said the “industrial ecology cycle” would be complete as the fertiliser produced from the AD process could be used on farmland to grow barley for Adnams beer.

“This facility will have a major impact on the reduction of carbon emissions in the region and the production of renewable energy,” he added.

“The food waste would otherwise be destined for landfill, but processing it through the digester will save an estimated 50,000 tonnes of CO2 equivalents from landfill.”

Gear�id Lane, managing director of communities and new energy at British Gas, said: “This project demonstrates how local communities can help us move to a low carbon energy future.

“Using waste that would otherwise end up in landfill to produce renewable gas is mutually beneficial for the environment and homes and businesses”.