
Harnessing the energy generated when freshwater meets saltwater - dnetesn
https://phys.org/news/2017-05-harnessing-energy-freshwater-saltwater.html
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hannob
There was actually already a test osmosis power plant in Norway. Unfortunately
it wasn't very successful and was shut down in 2013:
[http://www.statkraft.com/media/news/News-
archive/2013/Statkr...](http://www.statkraft.com/media/news/News-
archive/2013/Statkraft-halts-osmotic-power-investments)

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tim333
The output per sq meter at 12.6W seems rather low compared to solar cells at
150-200 W/ sq meter when sunny. It's probably going to be easier to stick up a
solar panel than a membrane contraption several times bigger.

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cbcoutinho
The benefit of osmotic power/salinity gradient power is that it's a base load.
That means it will produce power at a constant rate, regardless of the time of
day, which is one of the draw backs of the more common sources of renewable
sources of energy (solar, wind, etc.)

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hannob
Base load is not necessarily an advantage in a future energy system. Lots of
solar and wind means there will be times when all the electricity can be
provided by them. So what's really needed is flexible electricity to
complement that.

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ComputerGuru
At that point, it's free energy. Are you really complaining?

(Yes, I do know power companies must dissipate that somehow, my own even has
times whence the realtime pricing drops below zero as incentive. But a solved
problem nevertheless.)

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geon
The extra energy can be dumped into pumping water up a dam. It is reasonably
efficient, at 70-80%.

[https://en.m.wikipedia.org/wiki/Pumped-
storage_hydroelectric...](https://en.m.wikipedia.org/wiki/Pumped-
storage_hydroelectricity)

~~~
ZeroGravitas
Yes, but excess solar, wind and nuclear can already do that. So introducing a
new, so-called "baseload" power supplier doesn't automatically make for good
economics, if anything selling it as "baseload" rather than say "cheap" is a
bad sign.

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delinka
This is one of those "well why didn't _I_ think of that?" moments. It seems
awesome and I hope it pans out.

But really, I came here to comment on the odd phrase I found in an image
caption: "...synthetic freshwater or seawater..." I don't think I've ever
heard (seen?) anyone refer to anything water-based as "synthetic" simply
because the impurities were added by a human instead of by a riverbed.

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oneplane
And then use it in a desalination plant to make freshwater again?

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ptaipale
If the desalination is needed at another place where the power grid extends
but water pipes not - might be a useful idea.

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sprocketonline
A significant chunk of the world's population lives near river estuaries, so
there's a further possible benefit of this by having the power source near the
population and reducing transmission losses in the system.

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garou
What can be the impact of implementing it to the ecosystem?

I found nothing in the article. I hope they don't want to use it on rivers.

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the-dude
Not sure this is new, there are trials running in The Netherlands (
afsluitdijk )

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the-dude
Details : company is [http://REDstack.nl](http://REDstack.nl)

RED -> Reverse ElectroDialysis

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cbcoutinho
Wow, this is so cool - seeing the place I work at on HN.

