Essex potato farmers who diversified into crisp making are celebrating the opening of a new anaerobic digestion (AD) plant.

East Anglian Daily Times: Laura and Robert Strathern of Fairfields Farm.Laura and Robert Strathern of Fairfields Farm. (Image: Fairfields Farm)

Fairfields Farm at Wormingford, near Colchester, believes the investment, which means the business is entirely energy efficient, makes it the UK’s only hand-cooked crisp company powered solely by renewable energy.

The plant, which occupies the space of about 10 football fields, took two years to plan and build. It is situated right next to the farm’s crisp factory and its potato fields.

It digests organic matter, such as waste potatoes and crops such as maize and rye, and trillions of microorganisms anaerobically digest this to create gas.

The gas is collected, filtered and then exported to the national grid. A gas turbine is also on site, which produces electricity to power the crisp factory, potato pack-house, cold storage and offices. The gas produced for the grid provides enough power for 4,000 homes.

The AD process also produces organic digestate, which is high in nutrients and is ideal for spreading back on the fields to help soil structure and fertility on the farm.

The business has prided itself on its green-energy efforts, and has already installed solar panels on site, said third generation potato farmer and founder of Fairfields Farm crisps Robert Strathern.

“Minimising our environmental impact is very important to us. We’ve always made efforts to reduce waste and be as energy efficient as possible, so the new AD plant will allow us to fully realise our green potential,” he said.

“Apart from the obvious environmental benefits, the building of this AD plant will also enable us to better manage our power supply and remove the risk of future fluctuations in the energy market.

“This keeps us commercially lean and enables us to be viable and competitive well into the future.”

The family harvests potatoes, maize and rye across the Colne Valley. Their potatoes are cold stored, washed, graded and bagged to supply wholesalers and retailers across the region.

Special varieties of crisping potatoes are also grown to make Fairfields Farm crisps, which are now exported to 20 countries around the world. More product launches are planned this year.