The AD plant is fed with spent grains produced during brewing, ullage from the bottom of fermentation vessels and food waste from Adnams's pubs and hotels. The biomethane generated by the AD plant is currently cleaned and fed back into the grid. But this is to change.
"We are going to use the biomethane produced from our waste processes to fuel our commercial vehicle fleet and that will take 30% out of our carbon footprint when we manage to get all of our commercial fleet replaced over the next cycle of four or five years," said Adnams's chief executive Dr Andy Wood.
Adnams also plans to install a 0.5MW solar array that will provide all the electricity required to run the brewery's data centre and the AD plant. It will also feed back some electricity into the National Grid, according to Wood.
"This is the next step on our journey of industrial ecology," he said.
Adnams also plans to provide the 40 farms that supply it with barley for malting with fertiliser produced from the AD's two by-products leachate and digestate.
"There is some legislation at the moment that says you can't put it on the land throughout the year only at certain times. But that is likely to change," said Wood.
"We will then give that by-product back to our farms and they will have a free organic fertiliser."
Adnams has also adopted a range of other measures to reduce its environmental impact, including reducing the weight of glass used in some of its bottles. "By far the biggest part of the carbon emitting process is blowing glass," said Wood.