People walking their dogs are encouraged to collect the feces, place them into the supplied biodegradable doggie bags and drop them into the digester feeding tube. They then turn a hand crank to stir the mixture of excrement and anaerobic bacteria in the Spark Park digester and help the methane rise to the top where it is burned constantly in the lamp, like an “eternal flame”.

The bacteria are confined to an underground container and the methane is piped underground to the lamp. Methane is the colorless and odorless gas that forms the major component of “natural gas” used for cooking and heating.

The team hopes there will be enough methane generated to power other objects in the park and surrounding community, such as shadow projection boxes, tea carts, or popcorn stands, but the main aim is to demonstrate to the community that waste is a precious resource. “As long as people are walking dogs and throwing away dog poo, a flame can burn,” they say on their website.

The eternal flame of the lamp is intended as a reminder of the “redundant and unquestioned” nature of our behavior, and will burn until someone comes up with a better idea for using the energy available.