“The new bio-refinery at 2 Sisters Food Group’s Carlisle factory is expected to produce 3,500 megawatt hours (MWh) each year in electricity and the equivalent of 5,000MWh in steam to help power the factory. The anaerobic digestion plants will use potato waste from the factory’s mashed potato and pie manufacturing lines as a feed stock.” (http://www.theguardian.com/environment/2015/sep/29/mashed-potato-to-power-food-factory)

Their other rotten potato products are destined for incineration.

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