SOLution: Improving Low-Cost Water Disinfection

Everyday over 4500 children die due to lack of clean drinking water. Solar Disinfection (SODIS) is an inexpensive and effective method of water disinfection. Exposing clear plastic bottles filled with contaminated water to prolonged sunlight disinfects water making it safe to drink. Ultra-violet (UV) light and heat from sunlight kills bacteria,viruses and parasites. Studies have shown that SODIS requires 6 hours of sunlight, but cloud cover, location and seasonal changes cause the time required to vary. Real-world implementations of SODIS have been limited by the lack of a mechanism to determine and display when water is fully disinfected.

SOLution Brochure


SOLution is a solar-powered device that accurately measures sunlight and clearly displays when water is safe to drink. SOLution displays a universally recognized “happy face” or “sad face” to indicate water safety. SOLution is rugged, reliable and reusable. Constructed of parts typically found in a solar-powered calculator, SOLution is inexpensive (estimated < $5 USD), lasts for years and can be reused thousands of times and requires no maintenance (< $0.003 USD per use).

For more information, please download our SOLution brochure.