A tuk tuk, also known as an auto rickshaw, is a cheap, alternative form of transport found in countries across the world.
Usually three-wheeled and used as a vehicle for hire in developing countries, tuk tuks also provide a novelty form of transport in the West. They can be powered by petrol, LPG (autogas) and hydrogen (in more modern cases), but now the Denver Zoo has found another means to provide energy for their tuk tuks -- human trash and animal feces.
Believed to be the first hybrid-electric gasified version of the traditional three-wheeled transport, the tuk tuk has been designed and constructed in order to showcase the energy system that will power the Toyota Elephant Passage exhibit, open later this year.
The tuk tuk was imported from Thailand and then modified to run on gasified pellets sourced from animal feces and waste left by the Denver zoo's employees and visitors. The vehicle is the second machine to run on this kind of energy system --the first being a blender that was powered by the pellets in order to mix margaritas.
The entire process will take place on the zoo's grounds. Suitable waste and feces will join a 'waste flow' that becomes compacted together into pellets. These are then thermally broken down, and used to power items such as batteries, vehicles, heaters and pumps. The waste materials that cannot be broken down in this manner are metals, glass, and particular kinds of plastic.
Jennifer Hale, Denver Zoo's sustainability manager said:
"This is not just a zoo thing. It can be applied on campuses, in communities and many other environments."
If the model turns out to be efficient and fully functional, there is hope it may influence and alter attitudes to waste management -- which in turn could both help limit carbon footprints and reduce the amount of trash that finds its way on to landfill sites.
The finished, working model is expected to be complete and functional before fall.
The zoo estimates that it will be able to convert 90 percent of its waste and trash into a usable, renewable energy source -- offsetting 20 percent of the zoo's energy requirements. This, in turn, will eliminate 1.5 million tons of trash annually, and potentially save $150,000 per year in hauling costs.
See the tuk tuk in action:
(via The Denver Post)
Image credit: Edwin Lee