What if urine, something you flush away without a second thought everyday, could actually be useful? William Tarpeh, an Environmental Engineering PhD student from UC Berkeley is researching this very idea. Will spends most of his day extracting the nitrogen from pee to transform it into liquid fertilizer.

Recently, Will partnered with Sanergy, a company building toilets in the slums of Nairobi, Kenya. Sanergy collects feces for use in fertilizers, but before working with Will, they were disposing of thousands of liters of urine each day.

On a small scale, Will is able to turn urine into fertilizer very easily. The challenge is how to scale up and easily convert large amounts without raising the cost too much.

Watch the video above to see how Will is developing his process and how it could change the lives of billions of people around the world.

Thanks to our partner, the Blum Center for Developing Economies at the University of California, Berkeley, an innovation and research hub that is tackling issues in global poverty.

Read More:

Live Science: What's in Urine? 3,000 Chemicals and Counting

The Guardian: Waterless toilets turn human waste into energy and fertiliser

Sanergy: The Sanergy Model