Paignton Zoo aims to produce energy from animal dung

The Zoo – home to some of the largest animals in the world – plans to produce biogas with the help of microscopic organisms.

The conservation charity has joined forces with North Wyke Research, near Okehampton, part of Rothamsted Research, and Totnes engineering firm New Generation Biogas, who have developed a small-volume, high-throughput, hi-tech anaerobic digester. The partners will run a pilot project to evaluate the biogas producing potential of Paignton Zoo animal dung against other raw waste materials.

Curator of Plants and Gardens Kevin Frediani said: “As an environmental park we want to explore possibilities and test ideas – we can be the guinea pigs for new green technology and share the latest thinking with our half million annual visitors. This is a great partnership - North Wyke bring the science, New Generation Biogas the engineering and Paignton Zoo the raw materials.”

An anaerobic digester has been likened to a mechanical cow. It uses bacteria to break down organic waste, much like a cow's stomach. The major product of the digestion is methane, which can be used to generate heat or electricity.

There are many benefits to anaerobic digestion – it turns organic waste into energy and creates a valuable, nutrient rich, odour-free fertilizer. It also disposes of waste on site, so it doesn’t have to be taken long distances by road.

Paignton Zoo Environmental Officer Peter Morgan said: “The system that North Wyke Research and New Generation Biogas have developed will be about a quarter of the size of other digesters. It’s highly automated and can take all sorts of waste, from restaurant leftovers and grass cuttings to animal manure. There’s no smell and no health risk.”

Kevin Frediani: “In the future we could create a near-perfect environmentally-friendly model. We use VertiCrop to produce food efficiently on site for our animals, the animals produce dung, we use that dung and other waste material to help heat buildings including VertiCrop. It’s almost a closed system, with food miles reduced to food metres and power production as a bonus.”

Paignton Zoo animal dung is currently used to produce a garden compost called Zoo Poo. There are thousands of biogas plants on the Continent but only about 45 in UK.