Walkers makes fertiliser from beer and potato peelings

Crisps firm Walkers is creating climate-friendly fertiliser from potato waste mixed with carbon dioxide captured from beer fermentation.

The fertiliser will be available next year for farmers supplying Walkers, and the manufacturer says the new technology will reduce its carbon dioxide emissions from growing potatoes by 70%.

Walkers is working with clean tech company CCm Technologies and will install CCm equipment at its Leicester factory next year to begin wider production ready for the 2022 crop.

The new technology will stop carbon dioxide emissions from the brewing process, while also saving on carbon dioxide levels normally generated from fertiliser manufacture.

The fertiliser has been trialled on this year’s crop by Shropshire grower Robin Griffiths, who supplies 25,000t of potatoes each year to Walkers.

In mid-April, Mr Griffiths applied the solid fertiliser to about 1.6ha of VR 808 potatoes in one of his trial plots.

The farmer said it was difficult with only one year of data to fully analyse how effective the fertiliser is, but believed the yield was comparable.

“Applying it was very similar to applying a solid fertiliser down the furrow. The mechanics of applying it was borrowing some machinery that applied solid fertiliser, because we usually do liquid fertiliser. It is not much technology to get it incorporated.

“The real attraction is the 70% reduction in carbon. Producing a virtual circle product, you take a bit of waste, you treat it, you mix it with some other waste, and all of a sudden you’ve got a fertiliser you can use the following year,” Mr Griffiths said.

The farmer added it was important farmers engaged in initiatives that address climate change, in order to help gain public support for agriculture. “To get people to love farmers, we’ve got to be doing something green,” he said.

As the technology is rolled out to the manufacturer’s supplier farms more broadly, brand owner PepsiCo will be looking at ways to source the carbon dioxide from its own supply chain.

It said the initiative would drive more circularity in the growing process by turning potato waste into a reusable resource.

David Wilkinson, PepsiCo’s senior director of European agriculture, said: “This innovation with CCm Technologies could provide learnings for the whole of the food system, enabling the agriculture sector to play its part in combating climate change.

“This is just the beginning of an ambitious journey, we’re incredibly excited to trial the fertiliser on a bigger scale and discover its full potential.

“This initiative is a step in the right direction, and we will continue working hard to lower the carbon impact of our products from field, through manufacturing sites, to consumption.”