Life-saving Water Purification–Cheap

Here’s another possible lifesaver for the millions without access to clean water. Rice University nanotechnology researchers have developed a solar-powered sterilization system that uses nanomaterials to convert as much as 80 percent of the energy in sunlight into germ-killing heat.

Naomi Halas, the director of Rice University’s Laboratory for Nanophotonics, and Rice graduate student Oara Neumann presented the results of a study in

which nanoshells (invented by Ms. Neumann) were put in water and exposed to sunlight.  The result was steam, and a demonstrated 24% conversion efficiency (versus maybe 18% tops for solar cells).  They used the steam to purify water by distillation (duh) and also for sterilizing equipment in autoclaves(!).

The implications are staggering.

"Sanitation technology isn’t glamorous, but it’s a matter of life and death for 2.5 billion people," Halas said. "For this to really work, you need a technology that can be completely off-grid, that’s not that large, that functions relatively quickly, is easy to handle and doesn’t have dangerous components. Our Solar Steam system has all of that, and it’s the only technology we’ve seen that can completely sterilize waste. I can’t wait to see how it performs in the field.”

Bill Gates has taken an interest in this project.

___________

¹Compact solar autoclave based on steam generation using broadband light-harvesting nanoparticles Oara Neumann, Curtis Feronti, Albert D. Neumann, Anjie Dong, Kevin Schell, Benjamin Lu, Eric Kim, Mary Quinn, Shea Thompson, Nathaniel Grady, Peter Nordlander, Maria Oden, and Naomi J. Halas