Making microbe-powered tea lights in 7 steps: An adventure in hacking

Anne A. Madden, Ph.D.
Oct 1 · 7 min read
Me, posing with a petri plate covering half my face
Me, posing with a petri plate covering half my face
Me, posing with some microbes on a petri plate for a “cell-fie”
The Mudwatt microbial battery kit
The Mudwatt microbial battery kit
The Mudwatt microbial battery kit

Among the diverse communities of microbes are particular species with unique metabolic abilities that enable them to expel electrons onto oxidized metal compounds, such as rust. In a sense, these so-called “electrogenic” microbes are able to “breathe” metal compounds much like humans and other organisms breathe oxygen.”

An image of soil in a small glass vase with wires and a blinker LED board coming out of it.
An image of soil in a small glass vase with wires and a blinker LED board coming out of it.
My Mudwatt, soil, and vase set-up.
My cat trying to eat the wires on the Mudwatt
My cat trying to eat the wires on the Mudwatt
World’s worst assistant, Puffin the adventure cat.
A Honda key fob taken apart to reveal the battery
A Honda key fob taken apart to reveal the battery
Key fob I took apart to check that the LED I had was a flickering LED
A picture of the paper, paper towel roll and LEDs I used to make a paper tea light enclosure.
A picture of the paper, paper towel roll and LEDs I used to make a paper tea light enclosure.
The paper tea light holder I made from scrap paper and an old paper towel roll.
A tea light glowing, powered by microbes
A tea light glowing, powered by microbes
The final glowing microbe-powered tea light!

Anne A. Madden, Ph.D.

Written by

Microbiologist, inventor, and TED speaker Anne Madden studies the microscopic creatures that live in, on, and among us. Find out more at www.AnneAMadden.com

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