SEATTLE -- What if people living with untreated water could disinfect it for less than a penny a gallon?
Some University of Washington students say there's always been a way to do that and they've created a device to show when it's working.
The sun, if given enough time, can disinfect water in transparent containers, like clear plastic bottles.
"The simple rule of thumb that's been developed, is in six hours of direct sun or 12 hours of indirect sun," explains PhD.D. Student of Public Affairs, Tyler Davis.
Major relief groups and the World Health Organization accept the solar disinfection technique as an effective and safe water treatment method. But people are often reluctant to trust the system and want something to tell them when the water has been exposed to enough sunlight.
UW bioengineering student Jacqueline Linnes, working with the group Engineers Without Borders, began looking for a way to instantly test the water for safety. She turned to her friend, electrical engineering student Charlie Matlack, for help. Matlack went to work and by combining parts from cheap solar powered calculators and illuminating key rings, developed a concept for a portable device to that can attached to bottles, measure the exposure to sunlight, and indicate when it has received enough rays to reach disinfection.
"It's almost like something that would tell you if you've been sunburned yet, if you've been on the beach for a while, it's doing the same sort of function," said Matlack.
The concept impressed experts enough to win $40,000 in contest money from the Rockefeller Foundation. They plan to use that money to launch a non-profit organization to mass produce and distribute the devices to where they are needed most.