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Simple, solar-powered water desalination (2020)

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Re: Simple, solar-powered water desalination (2020)

#11

For those curious what the 385% refers to > the team’s demonstration device can achieve an overall efficiency of 385 percent in converting the energy of sunlight into the energy of water evaporation. Honestly I still don't know what that means, or how efficiency can be over 100%.

I think maybe it means "3.85 times as efficient as sunlight in evaporative filtering" ?

Re: Simple, solar-powered water desalination (2020)

#13
post #4

For those curious what the 385% refers to > the team’s demonstration device can achieve an overall efficiency of 385 percent in converting the energy of sunlight into the energy of water evaporation. Honestly I still don't know what that means, or how efficiency can be over 100%.

I guess water evaporates naturally, adding sunlight speed up the process.

And my perpetual motion machine uses naturally running hamsters.

Re: Simple, solar-powered water desalination (2020)

#14
post #2

This device "could" produce 1.5 gallons per day, per square metre of solar collecting area. The researchers estimate a system suitable for a family might be built for $100, so double or triple that after profits etc. I assume that the 1.5 gallons was the highest yield they would have had from a single day, had they had a 1 square metre solar panel, and the expected average yield would be less (accounting for cloud co…

The article says "per hour", not per day. Although that would seem able to support dozens of users rather than just 1.

Re: Simple, solar-powered water desalination (2020)

#15
It sounds like they figured out how to make the distillation version of a compound steam engine [0]. Like others, I’m confused by the efficiency number. Are they producing 385% more water for the same energy compared to the best single state result?

[0] https://en.m.wikipedia.org/wiki/Compound_steam_engine

Re: Simple, solar-powered water desalination (2020)

#18

For those curious what the 385% refers to > the team’s demonstration device can achieve an overall efficiency of 385 percent in converting the energy of sunlight into the energy of water evaporation. Honestly I still don't know what that means, or how efficiency can be over 100%.

I think it means 3.85x more water is evaporated compared to just leaving the water outside in the sun.

Re: Simple, solar-powered water desalination (2020)

#20

For those curious what the 385% refers to > the team’s demonstration device can achieve an overall efficiency of 385 percent in converting the energy of sunlight into the energy of water evaporation. Honestly I still don't know what that means, or how efficiency can be over 100%.

I'm not even sure what 'the energy of water evaporation' means? Gravitational potential of the mass of water evaporated (and condensed at some height)?
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