skip to main content

Green Revolution: Microbes

5 minutes

(Describer) In an animation, different colored icons include a car, a house, a model for hydrogen, and an arrow that looks like lightning. In another one, a woman connects cables. As she laughs and smiles, title: Green Revolution, with Lisa Van Pay PhD (Scientist).

(Describer) Other icons: toilet plus capsule shapes times faces with minus signs equals question mark. Title: Microbes.

(Describer) Water flows.

(Lisa Van Pay) Water is an important thing. We all need and use it. Life wouldn't exist on this planet without water. We put tremendous energy in figuring out how to ensure water's clean and available when needed. Could we use dirty water to clean itself, and make electricity?

(Describer) Clean water sparkles.

Then waste products could be used as fuel elsewhere. Penn State University researchers are examining how little creatures eating waste could someday make a difference by generating electricity.

(Describer) Lisa walks with Bruce Logan: Professor, Penn State.

(Describer) Title: energy from unlikely places. Logan:

(Bruce Logan) One core technology we study are microbial fuel cells. It's simply a box that we put water into, and bacteria-- not special bacteria,

(Describer) ...shaped like a capsule.

but they have a special property. They can chew up organic matter and release electrons to electrodes.

(Van Pay) Organic matter can be many things, including...

(Describer) A toilet is between parentheses.

[flushes] You get the idea.

Bacteria in the fuel cell eat this stuff. As part of their metabolism, they move electrons around. The trick is moving electrons where we want them. Here, we force bacteria to move electrons to carbon bristles.

(Describer) ...in the cell.

Eventually, the electrons build up, pushing each other across a circuit, powering fans, lights, or whatever you want. The result is decompose organic matter, producing harmless water.

(Van Pay) We're taking stuff we don't want anyway. With bacteria's help, it's turned into electricity to clean water, all without any pollution or emissions.

(Describer) Title: how can they work better? In another part of the lab...

I see you have many wires strung across your lab benches. What do you do with those?

(Logan) Each pair connects to one of these reactors, wired into this multimeter, which collects data from them.

(Van Pay) You're putting different bacteria

(Describer) Small boxes and jars.

in each of these and determine which one produces the most energy?

(Logan) Right, we could've put vinegar here, banana peels--whatever you'd like in each reactor. We're looking for those super bacteria, ones capable of producing very high current densities.

(Describer) Title: bigger is better. Right?

In the lab, you're obviously studying something on a small scale. How do you learn enough about it to do something that we could use in our houses?

(Logan) We can study these systems at very small scales. It allows us to quickly determine what factors affect power generation. We then have to understand what factors change when you make them larger. We go from smaller reactors to slightly bigger reactors, and then reactors the size of this bottle, to bigger reactors like this. It takes a lot of time and many different studies on a bunch of scales to understand how this works.

(Van Pay) The potential for bigger and better fuel cells is definitely there, and it's starting already. Bruce's team has set up multiple reactors-- now as big as refrigerators-- to make electricity for treating the waste water of a California winery.

(Describer) Title: better living through bacteria. Another small box is put together.

And it's not just researchers in big laboratories, nearly anybody can make microbial fuel cells. There are many tutorials and instructions online. People are building them now, for science projects, school assignments, or because they want to understand them. This simple, inexpensive fuel cell can be built anywhere, including places that don't usually have access to electricity.

(Logan) We're hoping this device would allow developing nations to have access to clean water and to treat waste water, simultaneously producing electricity. That could be used for lighting, charging cell phones, or just about anything.

(Describer) The first fuel cell runs a fan.

(Van Pay) Water treatment uses much of the world's energy. Using microbial fuel cells to power the process would make relying on other sources unnecessary. The National Science Foundation funds people like Bruce, who thinks of new ways to use world knowledge to help solve our problems. Sometimes small things can lead to really big ideas.

(Describer) A picture of a city is behind her.

I've always wanted to do this.

(Describer) She pretends to attack the buildings.

[monster roars]

(Describer) Icons: toilet plus capsule shapes times faces with minus signs equals a microbe with a lightning-shaped arrow.

(Describer) Titles: Produced by Bobby Mixon, Lisa Van Pay.

Transcript Options


Now Playing As: Captioned (English) (change)

Report a Problem

In Bruce Logan's lab at Penn State University, researchers are working on developing microbial fuel cells (MFC) that can generate electricity while accomplishing wastewater treatment. In a project supported by NSF, they are researching methods to increase power generation from MFCs while at the same time recovering more of the energy as electricity. Through their research projects, Logan’s team has already proven that they can produce electricity from ordinary domestic wastewater.

Media Details

Runtime: 5 minutes

Green Revolution
Episode 1
7 minutes
Grade Level: 7 - 12
Green Revolution
Episode 2
6 minutes
Grade Level: 7 - 12
Green Revolution
Episode 3
6 minutes
Grade Level: 7 - 12
Green Revolution
Episode 4
6 minutes
Grade Level: 10 - 12
Green Revolution
Episode 5
7 minutes
Grade Level: 7 - 12
Green Revolution
Episode 6
5 minutes
Grade Level: 7 - 12
Green Revolution
Episode 7
6 minutes
Grade Level: 7 - 12
Green Revolution
Episode 8
7 minutes
Grade Level: 7 - 12
Green Revolution
Episode 9
5 minutes
Grade Level: 7 - 12