Gross or great: a toilet that transforms human urine into fertilizer for flowers?
Researchers from the University of Michigan have come up with a toilet bowl that diverts liquid from solid wastes and then turns the urine into fertilizer.

The specially designed toilet bowl (at right) doesn’t look all that different. “We tried to make it as normal as possible,” said Krista Wigginton of the University of Michigan.
Eventually, Wigginton says, the fertilizer will enrich the university’s botanical gardens.
University of Michigan researchers are working on the project with colleagues at the Vermont-based Rich Earth Institute and the State University of New York at Buffalo. They say deriving fertilizer from nutrient-rich urine could save money and reduce pollution.
They’re not the only ones innovating with toilets, and the reason is simple: More than 2.5 billion people worldwide lack access to safe, clean bathrooms.
No water? No problem.
Could a revolutionary water-free toilet eliminate the need for plumbing? One person who thinks so is Bill Gates, the co-founder of Microsoft and a trustee at the Bill & Melinda Gates Foundation, the world’s largest private charitable foundation.
The foundation launched its “Reinvent the Toilet Challenge” in 2011. Several projects are underway, including the Nano Membrane Toilet at Cranfield University in the United Kingdom.
This project aims to treat human waste on-site without external energy or water and cost users no more than $0.05 per day.
The #nanomembrane #toilet on the @CranfieldUni stand at #NSLive pic.twitter.com/fMmkTDilAS
— Alison Parker (@AlisonP_WASH) September 23, 2016
This special toilet is still under development, with the first field trial expected this year. Researchers say the toilet could be great in dense urban areas where access to sanitation is challenging.
Space waste
To prepare for future space missions, U.S. space agency NASA is looking to upgrade its toilet tech.
In particular, NASA needed help figuring out how astronauts could go up to six days without a space toilet. So it launched the “Space Poop Challenge,” an online design competition, to ditch the extremely absorbent diapers that currently serve as astronauts’ means of last resort.

Designers got to work on modifications to NASA’s spacesuit, and NASA is now judging proposed solutions. The winner will receive a prize of $30,000.