Nature's power plants
On the hunt for renewable energy, scientists revisit Mother Nature's original power source: Photosynthesis and plants.
Photo: John Foxx/Getty Images Stockbyte 
Comments
If I had a lemon the size of a small house, I could power a small house for a month...
I'm wondering about the stability of these electrodes: how long do the enzymes on the electrodes stay reactive? I'm guessing not too long if you were to put a cactus in a +95F environment. In my experience, enzymes degrade relatively quickly, thus these electrodes might not be economically feasible. But it's a great idea! Good show.
Fascinating line of research. Next questions: 1) Can the extraction process be modulated to take more energy than the plant needs to grow (halting its growth or killing it)? 2) How effective is the process on plants other than cacti? 3) If the extraction machinery were hooked up to the root system of, say, a kudzu, could the kudzu be "drained dry"?
...the anti-global-warming crowds will start to love trees again..now that they know they can get personal profit from it (i.e. heat their homes for cheaper).
what i don't like is that it would take an awful lot of cactus to generate anything worthwhile here....
Solomont imports information from a Science Daily article he links to writing: "Inserted into a cactus, the electrodes generated 9 watts per square centimeter"
The Science Daily article includes an electircal symbol that Solomont leaves out..
"Furthermore, the researchers showed that a biofuel cell inserted in a cactus leaf could generate power of 9 μW per cm2." I believe that the μW symbol stands for a microwatt, a measurement of power equivalent to one-millionth of a.... More
"Inserted into a cactus, the electrodes generated 9 microwatts per square centimeter"
Thanks for the catch, David. You are correct that a small symbol makes a big difference in this story. We're updating the text now.
