Marwell Zoo

Marwell Zoo has designed and created an immersive energy and climate change visitor experience heated by sustainable ‘zoo poo’ biomass energy.

220 t
Est. annual reduction in carbon
emissions (tonnes CO2 eq)

500,000
Est. number of people
who benefit directly

Energy for Life Tropical House – Photo credit: Paul Collins.
Briquette machine – Photo credit: Paul Collins.
Loading the ‘zoo poo’ truck – Photo credit: Paul Collins.

Our story

by Marwell Zoo

Our Energy for Life initiative is a critical step in Marwell Zoo’s ongoing sustainability journey. Using biomass technology, we transform some of our 700 tonnes of animal waste – dung, soiled bedding, and hay – into renewable heat energy. This energy warms a unique visitor attraction, combining a tropical animal habitat with educational exhibits on energy flow, climate change, and powering modern lifestyles.

Previously, animal waste was taken off-site to be composted, and this came with a significant carbon transport cost. We came up with the idea of biomass heat generation to reduce our carbon footprint and turn a previous waste stream into a valuable resource – achieving cost savings in the process.

The type of waste we create is unique to zoos, very different to that of most farms, and on a smaller scale – so there was no plug-and-go solution available. We needed an approach that could harness our unique ‘zoo poo’ and be efficient enough to run on smaller quantities of fuel. We worked with experts to build a solution that blended different technologies, developing a unique system that allows us to process our waste into briquettes that fuel our biomass boiler efficiently.

The biomass heating system went live in 2021, and we will soon extend the system to warm several other buildings. The Energy for Life: Tropical House also uses the latest ETFE (Ethylene tetrafluoroethylene) roof technology which offers lots of natural light and provides good insulation. Rainwater is harvested from the roof to water the plants within.

We didn’t bring this project to life alone. The tropical house was developed with the support of Enterprise M3, and designed by Terrance O'Rouke with consultants Hoare Lee. Our onsite energy plant was constructed by Environ Ltd.

This project is just part of our wider commitment to becoming completely carbon-neutral and to championing renewable schemes in the local community. We also work with the council to host solar panels that power the national grid, practice sustainable land management, and through our head of sustainability, Dr. Duncan East, we chair the Winchester Sustainable Business Network.

Since 2008, we have reduced our carbon output by 77% and we are set to be a carbon-neutral organisation by 2022.

Our advice

Don’t wait – It’s easy to put off a project until you have more resources, or the technology has advanced, or for any number of reasons. But if you don’t get started, you won’t get anywhere. We have limited time to tackle environmental problems and it’s important to get on with it.

Be practical – There are lots of shiny, impressive-looking solutions out there, but none of them will work if they don’t make sense for the challenge you’re facing. You have to make sure a system or solution is a practical fit for what you’re trying to achieve.

Think innovatively – There may not be a single technology or solution that fits your unique challenge. Don’t be afraid to blend technology creatively to build something that works for you.

Our metrics

  • Overall site carbon reduction.
  • Number of visitors.

Read more: https://www.marwell.org.uk/zoo-news/powered-by-zoo-poo-we-unveil-our-innovative-energy-for-life-tropical-house/

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