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by ars 1488 days ago
Just in case you don't know: The energy to power your calculator did not come from the potato. It came from the metals you used in the potato. The metals are slowly oxidizing and that reaction (a kind of burning) produces the energy.

The same thing is happening here - it's not the algae producing energy, it's the metal anode and cathode.
1 comments
ryankrage77 1488 days ago
Did you read the article?

> "Because the experiment ran without any significant degrading of the anode the researchers believe that the cyanobacteria are producing the bulk of the current."

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ars 1488 days ago
I read the article. I saw what they said and I do not believe them for the following reasons:

1: Looking at an anode and saying "yup not corroded" is not how you check such things.

2: If they actually wanted to check it, there are several methods, they did none of them. They include: Weighing it, killing the algae and seeing if the power output changes, trying other metals for the anodes, trying other plants instead of algae in the water.

3: If you put salt water between two anodes you will get electricity. Period. If they claim this didn't happen, and "the algae did it", you're going to have to posit some method for the algae to prevent this, while substituting their own electricity. This will require new chemistry.

4: Algae are non-polar, so I don't see how they can direct the positive and negative current toward the proper anode to make electricity.

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gorgonical 1488 days ago
I have read the paper. They showed photosensitivity by both autoclaving the sample and adding DMCU to prevent photosynthesis. Both reduced power production. They do suggest a component of power production is related to electrolytic activity because they observe a dark setting power production; under a light setting the power production nearly doubles.

They also discuss the possibility that the algae are just promoting the oxidation of the aluminum, but do a series of assays I don't fully understand and conclude that some of the current produced is most likely from the algae themselves.

Link to paper: https://pubs.rsc.org/en/content/articlehtml/2022/ee/d2ee0023...

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hoseja 1488 days ago
How was this quantified? How much degradation would be expected if the amount of power were to be drawn from the equivalent battery without algae?
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