Engineering Students Fabricate Solar-Powered Autoclave

Four biomedical and mechanical engineering students are looking to reduce infection and the spread of disease by designing and fabricating a portable, solar-powered autoclave, that could be used to sterilize medical instruments and other scientific instruments.

Their design aims to bring medical sterilization to remote areas of the world with limited energy infrastructure through the use of solar panels, a lithium ion battery, an autoclave pressure vessel, a heating element, a step down converter and other small electrical safety features. The autoclave could be used following natural disasters and in third world countries.

Team member Shelby Pearce, a mechanical engineering junior, has always been interested in energy and how it impacts the world around us. The project has made her realize how much humans take electricity for granted.

“Humans are so reliant on energy, and this is one application that demonstrates how important electricity is to our quality of life,” Pearce said. “The project offers an opportunity to impact people who have very little.”

One of the teams biggest challenges has included balancing the volume of water to be boiled with the heating element while still maintaining a sterilization cycle time that is short enough to be powered by a battery. Pearce said the heating element draws 600Watts of power and must run for at least an hour. The autoclave can also be run on a natural gas burner.

The team has learned quite a bit about electrical wiring and components during the project.

“We underestimated how electrical heavy this project is, and we had a steep learning curve in regards to making sure all of our electrical components worked together,” Pearce said. “For instance, we didn’t know that we were going to need a DC-DC step-down converter until we got into to our initial testing phase.”

One of the biggest things student design has provided Pearce is the opportunity to work in a team for an extended period of time on a task from start to finish.

“None of my other college classes provided this, and when we get into the “real-world,” it isn’t just about a textbook,” Pearce said. “Many engineering companies put people into work teams for long-term projects, so this has been our first look at what that might be like.”

Pearce advises students to start as early as possible and don’t be afraid to ask for help outside your team.

“We hit a few roadblocks and once we talked to the right people, they made a big difference in helping us overcome the obstacles,” Pearce said. “Problems will pop up and student design isn’t something that could be easily done alone!”

Student design has challenged Pearce to incorporate her technological knowledge with her people skills to solve problems and create a successful end product.

“It teaches the design process and shows you the basics of what must go into designing and selling a product,” Pearce said. “Student design is an opportunity to actually apply all of the book knowledge that we have learned the past four years.”