But that’s where Rice University’s new solar steamer comes in. This ingenious device cheaply and easily captures the Sun’s rays to sterilise anything from scalpels to human excrement. Huzzah, no more infections from backwoods surgeries! And — bonus — your shit no longer stinks.
Developed at Rice University’s Laboratory for Nanophotonics (LANP), the Solar Autoclave machine uses nanoshells (small spherical nanoparticles with a dielectric core and metal skin) to convert both visible and invisible spectrums of light directly into heat — as much as 80 per cent of the incoming energy. Overall the system has an efficiency of just 24 per cent but that’s still way better than the 15 per cent efficiency of other solar technologies. And when submerged in water, they cause water to vaporise on contact generating enough steam and pressure to kill bacteria, mould and virii.
As you can see in the video below, the machine uses a parabolic mirror to capture the sunlight and concentrate the beam on a clear chamber containing the nanoparticles (the black sludge in the bottom) submerged in impure water. As the light shines on the chamber, the nanoshells absorb the energy, convert it to heat, and cause the water to spontaneously vaporise. The resulting steam can then be drawn off to either sterilise surgical equipment or condensed back in pure, potable water.
“Sanitation and sterilisation are enormous obstacles without reliable electricity,” said Rice photonics pioneer Naomi Halas, director of LANP and lead researcher on the project, in a press statement. “Solar steam’s efficiency at converting sunlight directly into steam opens up new possibilities for off-grid sterilisation that simply aren’t available today.”
The project is still in its prototyping stage but has already received funding from a number of major humanitarian organisations such as the Bill and Melinda Gates Foundation. If this device proves successful, more than 2.5 billion people around the world currently without access to sanitary water supplies or an electrical grid will have a means of doing so. [Rice News via Cleantechnica]