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The worst dam idea: evaporating the Mediterranean to power Europe

everythingisamazing.substack.com

31–40 of 64 posts

Re: The worst dam idea: evaporating the Mediterranean to power Europe

#31
If it is done can it easily for 1 country to threaten the whole euro … instead of nuclear bomb, we will bomb this dam. Giving the whole ww1 he has experienced can he just believe all countries are in it for peace. Also who will share the costs of losing the sea and maintain it.

Re: The worst dam idea: evaporating the Mediterranean to power Europe

#32

The Mediterranean sea is, to me, the most beautiful place on earth. Be it mainland Spain (with, sadly, way too many concrete all along the coast), France, Italy, Croatia, Greece, ... It's just beautiful. Then the islands: Corsica, Sicily, Ibiza, Formentera, ... It's heaven on earth. I drive my kid to school on the french riviera, along the coast and among the vineyards every day. Famous poets and painters would go an…

Couldnt agree more. (I grew up in Cyprus.) From what I could tell, it didn't occur to Sörgel what effect the dams and evaporation would have on sea-life, and on the coastal economies depending on it. Probably catastrophic. But one thing that was encouraging about the Orkney turbine mentioned elsewhere in these comments: they ran a trial first, to see how wildlife would be affected. Result: negligible impact. So a modern-tech version that respects all that beauty does seem to be possible - if mining the raw materials required to build it is factored in, because that is a massive ongoing issue.

Re: The worst dam idea: evaporating the Mediterranean to power Europe

#33

Someone with more engineering sense than I can debunk this: The Baltic is dramatically less saline than the Atlantic. That's why the Vasa [1] was so well-preserved after 300 years at the bottom. So could we not take advantage of that salinity difference, somehow? [1] https://www.vasamuseet.se/en Edit: Every engineering student sees the movie of the Tacoma Narrows bridge collapsing. To me, the Vasa is a much better ca…

We could. The technology you would use for this is https://en.wikipedia.org/wiki/Osmotic_power . Unfortunately, it is not currently cost-effective.

The salinity of the Baltic varies but is generally below 13 g/kg, which is a lot less than the salinity of the Atlantic (around 35 g/kg). This corresponds to an osmotic pressure differential around 1.8 kJ/L (1.8 MPa). If you were to build a dam which had a gravity pressure which matched this pressure differential it would be about 180 m high. So, yes, there is plenty of energy in that salinity difference, but getting it out in a cost effective manner is an open problem.

Re: The worst dam idea: evaporating the Mediterranean to power Europe

#34

Someone with more engineering sense than I can debunk this: The Baltic is dramatically less saline than the Atlantic. That's why the Vasa [1] was so well-preserved after 300 years at the bottom. So could we not take advantage of that salinity difference, somehow? [1] https://www.vasamuseet.se/en Edit: Every engineering student sees the movie of the Tacoma Narrows bridge collapsing. To me, the Vasa is a much better ca…

We could. The technology you would use for this is https://en.wikipedia.org/wiki/Osmotic_power . Unfortunately, it is not currently cost-effective. The salinity of the Baltic varies but is generally below 13 g/kg, which is a lot less than the salinity of the Atlantic (around 35 g/kg). This corresponds to an osmotic pressure differential around 1.8 kJ/L (1.8 MPa). If you were to build a dam which had a gravity pressur…

Excellent. Thanks!

Re: The worst dam idea: evaporating the Mediterranean to power Europe

#35
post #14

Something like this kind of drew me into geology. The inside jacket of my intro textbook explained the Mediterranean used to be damned naturally at Gibraltar or whatever the inlet is called and that so much salt water evaporated there where miles deep salt land features. Was instantly hooked

I'm sure I read about this in one of the later editions of Principles of Physical Geology by Arthur Holmes...

Re: The worst dam idea: evaporating the Mediterranean to power Europe

#37
post #3

Smaller scale project - Czech dam (the red lines are dams): https://www.abclinuxu.cz/images/screenshots/7/3/242837-ceska...

"The Czech basin can be conveniently used to build a giant reservoir"

I like his use of convenient. But the concept is quite interesting, barring the practicality of flooding Prague and half the country.

Re: The worst dam idea: evaporating the Mediterranean to power Europe

#38
post #14

Something like this kind of drew me into geology. The inside jacket of my intro textbook explained the Mediterranean used to be damned naturally at Gibraltar or whatever the inlet is called and that so much salt water evaporated there where miles deep salt land features. Was instantly hooked

This article links to another which discusses exactly that [1] — some geological event dammed the Mediterranean from the Atlantic 6 million years ago, after which the sea mostly dried out, then subsequently the entire thing refilled in the space of a couple years in the Zanclean Megaflood (at least, there’s mounting evidence that it happened in one cataclysmic event). First the western Mediterranean filled up to Sicily, then the eastern med, via a 1500m (5000ft) high waterfall!

[1]: https://everythingisamazing.substack.com/p/in-search-of-a-fl...

Re: The worst dam idea: evaporating the Mediterranean to power Europe

#39

The Mediterranean sea is, to me, the most beautiful place on earth. Be it mainland Spain (with, sadly, way too many concrete all along the coast), France, Italy, Croatia, Greece, ... It's just beautiful. Then the islands: Corsica, Sicily, Ibiza, Formentera, ... It's heaven on earth. I drive my kid to school on the french riviera, along the coast and among the vineyards every day. Famous poets and painters would go an…

Couldnt agree more. (I grew up in Cyprus.) From what I could tell, it didn't occur to Sörgel what effect the dams and evaporation would have on sea-life, and on the coastal economies depending on it. Probably catastrophic. But one thing that was encouraging about the Orkney turbine mentioned elsewhere in these comments: they ran a trial first, to see how wildlife would be affected. Result: negligible impact. So a mod…

I'm pretty sure he was a "change it all and we will make our own opportunity" type of dreamer, per the article.

Re: The worst dam idea: evaporating the Mediterranean to power Europe

#40
If global warming continues to raise sea level, it could well become the case that such a project is undertaken but with the goal of keeping the Mediterranean roughly where it is, which would simplify changes necessary elsewhere to keep the Black Sea a sea and keep harbors navigable.

Lowering the Mediterranean a few feet and running turbines at a flow rate to counteract evaporation might work, especially since evaporation and power usage track somewhat. Hot days evaporate more water, and require more air conditioning. The volume of the reservoir would allow quite a bit of buffer if you wanted to time shift some of that usage, aiming for monthly or quarterly averages instead of daily.

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