To produce zoo biogas for sustainable waste management and energy revenue makes a great deal of sense in a world seeking ways to fight climate change. The fact is that, zoos produce a lot of organic waste which is ideal for renewable energy production in a “biodigester” or anaerobic digestion facility.
Just visit any of the large animal enclosures at any zoo and your nose will tell you that there is animal waste present! Yes. Poo!
6 Zoos with Anaerobic Digestion and Biogas Plants Generating Energy from Animal Waste
Zoos are finding innovative ways to turn animal waste into clean energy using anaerobic digestion (AD) and biogas plants. These systems not only manage waste effectively but also generate renewable energy, reducing operational costs and environmental impact.
Here’s a list of zoos already making strides in sustainability by converting animal poo into green energy.
1. Toronto Zoo, Canada
Short Description: With its ZooShare Biogas Cooperative, Toronto Zoo has pioneered partnerships for environmental innovation.
- Key Features: Processes animal and local food waste into biogas.
- Energy Use: Powers the zoo and sells excess energy to the grid.
- Highlight: A robust educational program teaches visitors about sustainable practices.
2. Marwell Zoo, Hampshire, UK
Short Description: Marwell Zoo showcases the future of waste management with an anaerobic digester focused on sustainability.
- Key Features: Processes animal manure and bedding, reducing landfill waste.
- Energy Use: Helps power zoo operations while aligning with net-zero goals.
- Highlight: Recognized for its long-term commitment to carbon neutrality.
3. Noah’s Ark Zoo Farm, Berlin Zoo, UK
Short Description: Noah’s Ark Zoo Farm integrates green energy into its operations through its biogas plant.
- Key Features: Uses animal waste from their elephants (dung) for biogas production.
- Energy Use: Supplies power for animal enclosures.
- Highlight: The Munich Zoo is using large containers of 100 cubic metres each to catch the brown gold and each container holds about a week’s worth of elephant dung. The dung is mixed with warm water and left to decompose to produce a carbon dioxide and methane hybrid gas.
4. Detroit Zoo, USA
Short Description: Detroit Zoo integrates sustainability with its biogas system to manage waste and generate energy.
- Key Features: Processes animal and landscaping waste into renewable energy.
- Energy Use: We presume that it supports a portion of the zoo’s electricity and heating needs.
- Highlight: Reduces reliance on non-renewable energy sources, promoting eco-friendly operations.
5. Zurich Zoo, Switzerland
Short Description: Zurich Zoo embraces anaerobic digestion as part of its sustainability strategy. It des not have it's own biogas plant but states that certain wastes are used for biogas. We presume that this waste is collected and used at a local biogas plant.
- Key Features: Converts their catering waste and green waste into clean energy.
- Highlight: Green waste such as manure and food waste is used for biogas production.
6. Taronga Zoo, Australia
Short Description: Taronga Conservation Society Australia has a separate stream for food waste from their on-site operations.
- Key Features: Converts their catering waste into clean energy.
- Highlight: On average, they divert five tonnes of food waste from landfill by sending it to an anaerobic digester to create electricity and produce fertile pellets which return precious nutrients back into soil.
Why Anaerobic Digestion in Zoos Matters
These biogas plants highlight the potential for turning waste into a valuable resource. Zoos around the world are reducing their ecological footprint, inspiring others to adopt sustainable solutions, and educating millions of visitors annually about renewable energy.
Zoos are respected worldwide for their conservation work and preserving species diversity. They can act to inspire the public to follow their action on sustainability.
Your Turn!
Zoos with biogas plants show that innovation and sustainability go hand in hand.
Plan your visit to one of these eco-conscious zoos to see sustainability in action—and learn how even animal waste can contribute to a cleaner planet. Share this list with others and support organizations making strides for a sustainable future!
Archive Content posted in August 2021 follows:
4 Plentiful Zoo-Waste Sources
Zoos also produce food waste and other organic waste (biowaste) from:
- visitor pre-catering food preparation
- animal food preparation
- cafe and restaurant scraps, and
- organic waste from park and garden maintenance.
This is a ready source of supply for an anaerobic digestion plant producing renewable energy.
Zoos use a lot of energy, and most have targets that they want to meet to comply with the race to Net-Zero by 2030.
We recommend that all zoological organisations consider building and operating a biogas plant to:
- treat their organic waste and make renewable energy to run the zoo
- bring with it a considerable number of new local jobs
- help publicise the importance of sustainability in energy
- save money on waste disposal and treatment
- win the approval of their visitors: Most zoo attendees will be keen to see that their zoo is doing the best it can to maintain the biological diversity which is threatened by climate change.
- the composted output (digestate) may even be used to:
- Provided bedding for some of their animals
- fertilise the zoological park's gardens (subject to rules on sanitisation).
Read on to find out more about zoo biogas and the successful AD plant at the Detroit Zoo!
Zoo Biogas Plant at Detroit Zoo Turns Zoo Waste into a Natural Renewable Energy Source
The zoo's $1. 2 million anaerobic digester, which was installed in 2017, converts approximately 500 tonnes of their animal excrement and other organic waste into compost.
Excess gas is subsequently converted into an alternative energy source, which is used to power the zoo's Ruth Roby Glancy Animal Health complex.
“most institutions would not even consider putting it in, because the return on investment is quite long,”
Hanbury says of the digester:
“that’s a particular instance where we are a leader in green innovation.
US Zoo is Using Anaerobic Digestion to Reach 100% Renewable Energy Goal
The Detroit Zoological Society (DZS) is pursuing its aim of 100 percent sustainable energy through anaerobic digestion. The zoo in Michigan has already erected an anaerobic digester that takes 500 tonnes of herbivore waste and food scraps from landfill and converts them to energy and compost. In a statement, DZS announced that the company has won four green awards for its sustainability activities and accomplishments.
The zoo has also installed solar and electric hybrid golf carts as well as bicycles for onsite transportation in addition to its anaerobic digestion.
Detroit Zoo Plans to Turn Animal Waste Into Energy
The following is our original article published on 28 April 2015. It is still relevant today:
Anaerobic Digestion to be Detroit Zoo's Newest Attraction and to Use Crowdsourcing
Animal waste is commonly used as fertilizer but it can now be utilized as an endless supply of energy thanks to Anaerobic Digestion. Zoos in the U.S. on average each create around 400 tons of animal waste a year and that amount of waste can easily be processed and used to provide at least 10% of their energy needs.
The Detroit Zoological Society is the first in the U.S. to take advantage of Anaerobic Digestion by using the waste of zoo animals. It launched a crowdfunding campaign for its Detroit Zoo AD plant last week. It is hoping to save at least $80,000 yearly in the facility’s energy costs, as well as about $40,000 in waste disposal.
The Detroit Zoo also plans on reducing its greenhouse gas emissions by 20% this year and has a goal to achieve zero waste by 2020.
“We’ll be the first zoo in North America to have a dry biodigester on grounds, turning the dry animal waste into electricity,”
said Gerry VanAker, the Chief Operating Officer of the Detroil Zoological Society.
“There’s also a zoo in Munich, Germany that operates a biodigester, and the Toronto Zoo is in the early phases of developing one.”
Tell Me More About Anaerobic Digestion
Anaerobic Digestion is a sequence of biological processes in which microorganisms are broken down into biodegradable materials to produce biogas. The biogas is then combusted (burnt) in order for it to generate electricity or heat. The biogas byproduct consists of methane (CH4), carbon dioxide (CO2), and other forms of gases.
Sulzer, an engineering company that is in partnership with Unaoil, says that a successful anaerobic digestion plant requires temperature equalization and the proper homogenization of the biomass. In addition, for the production of high-quality biogas, the formation of floating crusts on the top of the liquid substrate should be prevented, and foam formation must be avoided.
Detroit Zoo’s new biodigester equipment will save on waste disposal costs, and also generate energy, but will have a high initial capital cost, and the Detroit Zoological Society’s existing funding is not enough to purchase it. As a result, the society has started a crowdsourcing operation with a target goal of $55,000 by June 16th.
We think that this use of crowdsourcing was probably another first for the zoo!
Image Attribution: By JJ Harrison (jjharrison89@facebook.com) (Own work) [GFDL or CC BY 3.0], via Wikimedia Commons
[Original article published on 28 April 2015. Updated August 2021 and December 2024.]
Cool Article. Our documentary film “Sh*t Saves the World” visited the Detroit Zoo as part of our film. It is a very cool idea! Our film was just released last week on Amazon, Apple TV, iTunes and many more if you are interested in taking a look. I was getting ready to reach out to Zoos about our film when I came across your article.