To help solve a long-standing health issue for developing countries, students at Rice University are using the sun to power an autoclave that sterilizes medical instruments. The engineering students used Capteur Soleil, a device created by French inventor Jean Boubour, to use solar energy in locations where electricity – or fuel of any kind – is hard to obtain. By attaching an insulated box that contains the autoclave, the students have transformed the device into a potential lifesaver. Capteur Soleil resembles an ultramodern lawn swing, with a steel A-frame spine and a bed of curved mirrors beneath the frame that focus sunlight along a steel tube at the frame’s apex to produce steam. Rather than pump steam directly into the autoclave, the Rice students decided to use the steam to heat a custom-designed conductive hot plate. When the hot plate reaches 121 °C – the standard set by the Centers for Disease Control and Prevention – for 30 minutes, the contents within the autoclave should become sterile. Within half an hour of receiving strong sunlight, the Capteur Soleil will begin to produce steam, which will then heat the patterned hot plate and then the FDA-approved autoclave. With good midday sun, the students said it takes about 40 minutes to an hour to begin significant heating of the autoclave. With a steamer basket and medical instruments inside, the autoclave is wrapped in silicon-based Thermablok insulation, which has the highest R-value of any known material and is a spinoff from NASA research into thermal protection for the space shuttle. To check the system, the team used some biological spores from a test kit, steamed them and then incubated them for 24 hours. The tools came back negative for biological growth, meaning that whatever was in them was killed in the autoclave. “This is really the latest iteration of a much larger project,” said Doug Schuler, the team’s faculty adviser and an associate professor of business and public policy at Rice’s Jones Graduate School of Business. “We already have a version of the Capteur Soleil being used in Haiti for cooking, but we felt it could do more.”