Sterile medical equipment is crucial in preventing infection, and it's something we take for granted with our powerful, industrial autoclaves, which use heat to render medical equipment sterile. But in the thousands of off-the-grid clinics and health stations around the world, creating sterile equipment isn't so easy. That's why The Little Devices group at MIT choose it as a challenge, and their solution was a solar concentrating system that sterilizes medical tools using locally sourced materials and the sun.
The SolarClave uses the build up of the sun's power to heat and pressurize a chamber filled with medical equipment, killing any dangerous microbes inside. The system suspends an insulated "cooker" in a bucket over an array of 140 pocket sized mirrors. On a clear day, the mirrors concentrate the sun's power over about an hour to 250 degrees Fahrenheit, the temperature needed to sterilize the equipment. The sterilization cycle then lasts 20 minutes.
One of the critical measures for the team at MIT was that the system not be developed in the vacuum of laboratory conditions. They worked with nurse practitioners and health care workers in the field in Nicaragua to get feedback on how the device would best work in real world conditions, and how it could be sustainable in remote locations. First attempts used a boiler suspended over foil reflectors and a system of tubing to power a sterilization chamber a few feet away. This proved complicated to build, operate, and fix in the field, while the current solution is much more resilient.
Currently, remote clinics in Nicaragua and around the world have to rely on existing kerosene-powered autoclaves, or in more dire conditions, boiling medical tools. In many cases, the only solution is transporting a patient to one of these clinics or more sterile hospitals, incurring added time and risks. The SolarClave could prove to be a viable first line of defense against infection for those treated in local off-grid clinics. The system will be tested in three locations in Nicaragua over the summer, and a search for local producers will follow.
SolarClave via SmartPlanet and MIT News