Live data from Hacker News

Quantum Dots Shift Sunlight's Spectrum to Speed Plant Growth

spectrum.ieee.org

11–20 of 29 posts

Re: Quantum Dots Shift Sunlight's Spectrum to Speed Plant Growth

#11
post #3

This is pretty awesome. A lot of vegetables are grown in greenhouses, but traditional greenhouses are quite energy intensive. Anything that reduces the need for greenhouse area could save quite a bit of carbon. Paired with techniques [1] to reduce the amount of heating needed, this could be a real game changer. [1] https://www.lowtechmagazine.com/2015/12/reinventing-the-gree...

Maybe. The question is: Are QDs building energy efficient? Or does it require high-energy chemical reaction.

Re: Quantum Dots Shift Sunlight's Spectrum to Speed Plant Growth

#13
post #10
post #2

I wonder what would be the side-effects of speeding up plant growth.

I think you have a point. There's no free lunch in evolution based systems, at least that's my perception.

No evolution needs to happen in a controlled environment.

Re: Quantum Dots Shift Sunlight's Spectrum to Speed Plant Growth

#15
This isn't too surprising. It's the same improvements people have been expecting from using solar panels and LEDs to grow plants.

Since numbers and mechanisms aren't really explained I'll drop some numbers here: ~50% of incoming sunlight energy is lost to plants just by falling outside of the range that chlorophyll can absorb (400-700nm). ~25% of the light energy that is absorbed, is lost by dropping the higher energy wavelength light (the 400nm/blueish end) to the 700nm level needed for the rest of the process.

Just from these two losses you're at 37.5% efficiency, so converting to better wavelength light either by quantum dot or solar panels/LEDs has a massive impact on crops grown per area, particularly in higher latitudes.

Just for reference, the most efficient plants (heavily bred/modified crops) are in the range of 1-2% efficient for the whole photosynthetic process.

https://en.wikipedia.org/wiki/Photosynthetic_efficiency

Re: Quantum Dots Shift Sunlight's Spectrum to Speed Plant Growth

#16
post #10

Earlier quoted context omitted.

I think you have a point. There's no free lunch in evolution based systems, at least that's my perception.

No evolution needs to happen in a controlled environment.

Plants have evolved to adapt to a certain environment, and if we change those parameters to promote a certain behaviour (e.g. higher yield) then most likely it comes at a cost (e.g. is the produce less nutritious?)

Re: Quantum Dots Shift Sunlight's Spectrum to Speed Plant Growth

#17
post #8

Would this make up the difference for the dimmer light on Mars?

The white paper shows an increase of 20%, but solar irradiance on Mars is about 60% of what you can get on Earth (below the atmosphere). So it would be equivalent to 60% * 120% = 72%.

Re: Quantum Dots Shift Sunlight's Spectrum to Speed Plant Growth

#18
post #16

Earlier quoted context omitted.

No evolution needs to happen in a controlled environment.

Plants have evolved to adapt to a certain environment, and if we change those parameters to promote a certain behaviour (e.g. higher yield) then most likely it comes at a cost (e.g. is the produce less nutritious?)

Evolution does not optimize to global maxima, it prefers local maximas. The path it has taken so far is also pretty convoluted.

Re: Quantum Dots Shift Sunlight's Spectrum to Speed Plant Growth

#20
post #2

I wonder what would be the side-effects of speeding up plant growth.

You could probably distribute the light among a larger number of plants (think plants stacked on a shelf, or on a tilted surface), so you grow more instead of faster.
Post reply on HN