IEEE Spectrum is the flagship publication of the IEEE — the world’s largest professional organization devoted to engineering and applied sciences. Our articles, podcasts, and infographics inform our readers about developments in technology, engineering, and science.
Enjoy more free content and benefits by creating an account
Saving articles to read later requires an IEEE Spectrum account
The Institute content is only available for members
Downloading full PDF issues is exclusive for IEEE Members
Access to Spectrum's Digital Edition is exclusive for IEEE Members
Following topics is a feature exclusive for IEEE Members
Adding your response to an article requires an IEEE Spectrum account
Create an account to access more content and features on IEEE Spectrum, including the ability to save articles to read later, download Spectrum Collections, and participate in conversations with readers and editors. For more exclusive content and features, consider Joining IEEE.
Join the world’s largest professional organization devoted to engineering and applied sciences and get access to all of Spectrum’s articles, archives, PDF downloads, and other benefits. Learn more →
IEEE Members receive 12 print issues of IEEE Spectrum and enjoy PDF downloads, full access to our archive
with thousands of in-depth articles, and other exclusive content and features.
today for 2023 and save 50%!
Made by Singapore’s Nanyang Technological University, the No-Mix Vacuum toilet diverts urine, which is rich in nitrogen, phosphorous and potassium, to a processing facility. There these elements are extracted for use in products such as fertilizer. The fecal matter goes to a bioreactor where it is digested and yields a biogas rich in methane. The methane can be used in stoves for cooking or in turbines for generating electricity. Because of its vacuum suction, the toilet needs only 0.2 liters of water to flush away liquids; getting rid of solids takes about a liter of water. Today’s toilets use up to 20 times as much water for each flush.
Willie Jones is an associate editor at IEEE Spectrum. In addition to editing and planning daily coverage, he manages several of Spectrum's newsletters and contributes regularly to the monthly Big Picture section that appears in the print edition.