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Simple, solar-powered water desalination (2020)

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

#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 cover etc.)

But even with reduced yield, for very small communities of a few dozen people, this definitely could work out.

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

#3
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%.

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

#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.

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

#7
post #6

What's the point here? Is electricity even the bottleneck of water desalination? I thought the biggest issue with these plans is the brine. That is the major pollutant, and no amount of solar panels will solve that.

The article directly addresses your point.

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

#8
post #6

What's the point here? Is electricity even the bottleneck of water desalination? I thought the biggest issue with these plans is the brine. That is the major pollutant, and no amount of solar panels will solve that.

Reading the article might help:

> Unlike some desalination systems, there is no accumulation of salt or concentrated brines to be disposed of. In a free-floating configuration, any salt that accumulates during the day would simply be carried back out at night through the wicking material and back into the seawater, according to the researchers.

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

#9
post #5

Is the water pumping also passive? I'm just assuming that you'll have salt water on a lower level, and you'll need to lift it up to this installation to process it.. with a pump.

The article suggests it could float:

> In a free-floating configuration, any salt that accumulates during the day would simply be carried back out at night through the wicking material and back into the seawater, according to the researchers.

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

#10
post #6

What's the point here? Is electricity even the bottleneck of water desalination? I thought the biggest issue with these plans is the brine. That is the major pollutant, and no amount of solar panels will solve that.

Brine is the biggest issue with some desalinators, not this one.

Power can be a constraint, too. It depends on how much power you have available or can pay for, how much fresh water you need and how pure, how much you can buffer, etc. In short, power/cost is a constraint sometimes.

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