Bacteria: Energy Producers of the Future
Environmental engineer Bruce Logan is working on ways to turn wastewater into energy. Most treatment plants already use bacteria to break down the organic waste in the water. With support from the National Science Foundation, Logan and his team at Penn State University are taking the idea a step further. They are developing microbial fuel cells to channel the bacteria's hard work into energy.
Transcript
00:00:12 MILES O'BRIEN: Water, water everywhere, but what pours in must drain out. Waste water treatment plants clean it before it flows back to the environment. It's a process that takes time, money, and a whole lot of energy. But what if waste water could itself be turned into energy. Sound too good to be true? BRUCE LOGAN: We can literally take this, pour in the waste water, and we make electricity. MILES O'BRIEN: Environmental engineer Bruce Logan is working on ways to make that happen. BRUCE LOGAN: We're using bacteria to actually turn any organic matter and some inorganic matter direct into electricity. The bacteria do it themselves, and that's how we're running this fan. MILES O'BRIEN: Some treatment plants already use bacteria to break down the organic
00:00:57 waste in the water. With support from the National Science Foundation, Logan and his team at Penn State are taking that idea a step further. They're developing microbial fuel cells to channel the bacteria's hard work into energy. BRUCE LOGAN: We can make all sorts of different kinds of energy. MILES O'BRIEN: Here's a little cartoon that shows how it works. The bacteria eat the organic waste, releasing electrons as a byproduct. Those collect on carbon bristles in the fuel cell, eventually flowing through a circuit, shown here powering a light bulb. BRUCE LOGAN: We're looking at how we link these reactors together in order to multiply the power. MILES O'BRIEN: Logan says these wastewater batteries will be useful if they can generate
00:01:39 enough energy to be cost effective. BRUCE LOGAN: In the early reactors we used very expensive graphite rods and precious metals like platinum, and we've now reached the point where we don't have to use any precious metals. MILES O'BRIEN: The latest versions are already using cheaper, more environmentally friendly materials, and Logan is testing another system that would use saltwater in the fuel cell to generate even more electricity. BRUCE LOGAN: You're actually creating energy and desalinating the water and treating the waste water. It's, you know, a triple play. MILES O'BRIEN: Logan expects it will be at least five years before these microbial fuel cells are ready
00:02:15 for use in the real world. The goal is that they would eventually be able to generate enough electricity to power an entire waste water treatment plant, maybe even more. And that's a powerful idea. For Science Nation, I'm Miles O'Brien.