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Computer powered by colony of blue-green algae has run for six months

newscientist.com

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Re: Computer powered by colony of blue-green algae has run for six months

#11

Post by ascar »

elsherbini wrote: post #6
phtrivier wrote: post #3

Stupid question : do the bacteria manage the create their organic mass entirely from air + sunlight, or does the "container" need a special substrate / soil / etc... ? How fast would that "deplete" relative to the metals in the anode / cathode ? Also, how much does it "capture" carbon as part of the photosynthesis ?

Here are a bunch of different media people use to grow cyanobacteria: https://www-cyanosite.bio.purdue.edu/media/table/media.html Mostly they need nitrogen, phosphate, and sulfur to make protein and nucleic acids, and trace metals,ions, and some vitamins to use as cofactors for enzymes. In the wild, the limiting nutrient for cyanobacteria is often iron or nitrogen. They don't need an added carbon source in their medi…

> In the wild, the limiting nutrient for cyanobacteria is often iron or nitrogen.

How can nitrogen be a limiting factor if ~78% of air is nitrogen? I'm assuming they also take the CO2 out of the air, which just makes up 0.04%.

Re: Computer powered by colony of blue-green algae has run for six months

#12

Post by couchand »

ascar wrote: post #11
elsherbini wrote: post #6

Earlier quoted context omitted.

Here are a bunch of different media people use to grow cyanobacteria: https://www-cyanosite.bio.purdue.edu/media/table/media.html Mostly they need nitrogen, phosphate, and sulfur to make protein and nucleic acids, and trace metals,ions, and some vitamins to use as cofactors for enzymes. In the wild, the limiting nutrient for cyanobacteria is often iron or nitrogen. They don't need an added carbon source in their medi…

> In the wild, the limiting nutrient for cyanobacteria is often iron or nitrogen. How can nitrogen be a limiting factor if ~78% of air is nitrogen? I'm assuming they also take the CO2 out of the air, which just makes up 0.04%.

Not the GP and I do not have relevant scientific expertise, but my memory from beer is that CO2 stays dissolved longer than N2? Are they underwater?

Re: Computer powered by colony of blue-green algae has run for six months

#13

Post by elsherbini »

ascar wrote: post #11
elsherbini wrote: post #6

Earlier quoted context omitted.

Here are a bunch of different media people use to grow cyanobacteria: https://www-cyanosite.bio.purdue.edu/media/table/media.html Mostly they need nitrogen, phosphate, and sulfur to make protein and nucleic acids, and trace metals,ions, and some vitamins to use as cofactors for enzymes. In the wild, the limiting nutrient for cyanobacteria is often iron or nitrogen. They don't need an added carbon source in their medi…

> In the wild, the limiting nutrient for cyanobacteria is often iron or nitrogen. How can nitrogen be a limiting factor if ~78% of air is nitrogen? I'm assuming they also take the CO2 out of the air, which just makes up 0.04%.

Some cyanobacteria can take up nitrogen from the air (well, dissolved inorganic nitrogen), but many can only use organic nitrogen, like N03 or NH4. Those can be limiting in the ocean because lots of life wants to grab it up.

Taking up inorganic nitrogen is called nitrogen fixation and takes a bunch of machinery and energy. Also, oxygen inhibits the process, so for photosynthetic bacteria a bunch of extra steps have to be taken to compartmentalize photosynthesis and nitrogen fixation. So not all cyanobacteria can do it, and even the ones who are able to will prefer to take up organic nitrogen if available, and they grow slower when they have to use N2.

Re: Computer powered by colony of blue-green algae has run for six months

#15

Post by maccard »

bin_bash wrote: post #9
withinboredom wrote: post #2

I find it funny that a mobile was listed as "low power devices." Phones these days consume quite a bit of electricity, unless they are referring to old-style flip phones, which might use quite a bit less power.

What like 10w? That’s nothing compared to almost any other application of electricity.

What's your comparison to there? 10w is a reasonable amount of power and you can do lots with it - my M1 Mac can browse the internet on 10w of power.

Re: Computer powered by colony of blue-green algae has run for six months

#16

Post by bin_bash »

maccard wrote: post #15
bin_bash wrote: post #9

Earlier quoted context omitted.

What like 10w? That’s nothing compared to almost any other application of electricity.

What's your comparison to there? 10w is a reasonable amount of power and you can do lots with it - my M1 Mac can browse the internet on 10w of power.

It’s a reasonable amount for computing but not much else: heating, cooling, cooking, refrigeration, washing machine. Those all need vastly more electricity.

About the only other household application of electricity I can think of that would use around 10w is lighting and even with LEDs it isn’t much. Probably enough for a single room.

My point is if mobile phones aren't considered “low power”, then what would be?

Re: Computer powered by colony of blue-green algae has run for six months

#17

Post by phyalow »

LoveMortuus wrote: post #4

> The computer ran in cycles of 45 minutes of calculating sums of consecutive integers to simulate a computational workload, which required 0.3 microwatts of power, and 15 minutes of standby, which required 0.24 microwatts. The computer itself measured the current output from the device and this data was stored in the cloud for researchers to analyse. > Christopher Howe at the University of Cambridge and his colleagu…

I remember running a calculator via a potato battery when I was much younger.

Re: Computer powered by colony of blue-green algae has run for six months

#18

Post by samstave »

It would be really interesting to see if "light pipes" ('fiber' optics that can funnel sunlight to interior spaces.

So stack a bunch of these vertically, but have a light-pipe to each little window to the algea to feed them photons.

Trickle charge batteries?

Re: Computer powered by colony of blue-green algae has run for six months

#20

Post by kderbyma »

brilliant. lets use this with skyscraper design to build in aquaponics into the sides of the buildings and get food production, power generation, and local garden life. and everyone can look out into a garden Oasis with algae generating some of the power back into the system.
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