Marwell Zoo in Winchester is opening an £8 million Tropical House powered entirely on poo.
The rainforest is a two-toed sloth, mouse deer, and pygmy marmosets on their own primate island. There are also free-flying birds and more than 2,500 fish in the aquarium.
James Cretney, Marwell Zoo's Chief Executive, commented: ''This exhibit is a key guest experience with complementary education and sustainability.
''It provides close animal viewing while setting new standards of husbandry for the species displayed. We are very excited about this.''
Marwell Zoo will convert some of its 700 tonnes of animal waste into energy to heat the site and other buildings across the zoo. Woodchip will also heat the site's buildings, reducing the zoo's dependency on fossil fuels, with the goal of becoming carbon neutral by 2020.
The exhibit's curved roof uses the latest technology. An insulating canopy lets natural light shine through, creating perfect conditions for 650 plants. More than 65 different plant species thrive and form a home for the animals. Recycled rainwater from the roof provides water for the plants and aquarium.