If you live in a big city, then there are doubtless alleyways or alcoves you know of that always smell like pee. While it might help to install public urinals in these places, doing so involves a lot of work and expense. Porta Potties are one alternative, although Oakland, California-based Hyphae Design Laboratory has developed a more eco-friendly solution known as the PPlanter. It's a self-contained modular system, that uses bamboo to process the pee.
Here's how the PPlanter works ...
A user steps up and pees into the actual urinal itself, with their mid-section hidden by a privacy panel (disposable funnels are provided for women, so they can do their business standing up). When they're done, they use a foot pump to draw water from an attached reservoir through the faucet of a built-in sink, allowing them to wash their hands.
Once it's gone down the drain, the used wash water rinses out the urinal, with the urine and water then carried into an airtight tank. From there, the mixed liquid is pumped into the planter/biofilter, where bamboo plants are growing in a mixture of rocks, wood chips and styrofoam. The water, nitrogen and phosphorous are used by the bamboo, while bacteria living in the growing medium break down carbohydrates and protein. There is reportedly little if any smell.
According to a report in New Scientist, a prototype has been tested in a crowded San Francisco neighborhood, where it stood up to use by over 300 people within an 8-hour period. The city has now ordered a permanent PPlanter. Hyphae hopes to rent the urinals out for use at special events, along with getting them to developing nations that lack proper sewers, and putting more of them on the streets.
The concept is outlined in the video below.
Sources: Hyphae Design Laboratory, PPlanter via New Scientist