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> Desalination used to be an expensive energy hog, but the kind of advanced technologies being employed at Sorek have been a game changer. Water produced by des

by abalone 10y ago

> Desalination used to be an expensive energy hog, but the kind of advanced technologies being employed at Sorek have been a game changer. Water produced by desalination costs just a third of what it did in the 1990s. How much of that price drop is due to lower energy prices? How sustainable is the power source? Even with significant efficiency improvements (3X), shifting from local freshwater sources to desalination would have a massive energy requirements.[1] For such a bold claim ("the Desalination Era is Here"), this article has a rather lightweight examination of the environmental impacts. [1] https://en.wikipedia.org/wiki/Desalination#Energy_consumption https://en.wikipedia.org/wiki/Desalination#Energy_consumptio...

einhverfr 10y ago
One of my favorite takes on this topic is Clarke and Dawe's take on the Victoria desalination project[1] (the two are comedians). [1]https://www.youtube.com/watch?v=X_SrrylkIEc https://www.youtube.com/watch?v=X_SrrylkIEc
- vacri 10y ago
  It's a bit sad, though - the Victorian government was in a no-win situation with that one. A nine-year drought with the water reserves to a city of 4M people down to 15%? Something had to be done, and the common refrain of "drought will break next year" had been heard every year for the previous half-decade. The plant was over-expensive and should have been bought in a progressive manner rather than full-capacity-at-once, but Melbourne was actually in danger of running out of water. They joke in the video "why not build a dam where it's actually raining?", but the point was, there'd been barely any rain for a decade. There wasn't anywhere that fit that description (and Melbourne has tons of water reserves outside of long drought conditions). Of course, because Fate is an arsehole, they got the construction underway, and the next year the drought broke. If the drought hadn't broken, people wouldn't be so quick to condemn the desal plant...
aaron695 10y ago
> How sustainable is the power source? Oil (and such and such) will last a 100+ years and obviously won't destroy the planet in that time. I'd call that sustainable. And given it's just a "power source", at any time we could swap it out for X, Y, Z. Plus they specifically talk about efficiencies in the article? Not sure your point at all? I haven't seen huge drops in energy cost across the world? Electricity seems the same or more than the 1990s?
- throwaway5752 10y ago
  "Oil (and such and such) will last a 100+ years and obviously won't destroy the planet in that time." It is not at all obvious that it won't.
- andrewjl 10y ago
  Two words: climate change
  - polotics 10y ago
    Yep. Three words: Black flag weather
Dylan16807 10y ago
They're quoting 58 cents for a thousand liters. Even if we pretend that is based on free power, we can add the cost of a solar plant and produce each thousand liters for under a dollar. So desalination is completely sustainable.
- abalone 10y ago
  That's like saying all high-energy industries are sustainable, if we assume sufficient solar build-out. That's a big if. We can't just assume this project is going to be powered sustainably. It's something the article should have explored.
  - Dylan16807 10y ago
    > That's like saying all high-energy industries are sustainable, if we assume sufficient solar build-out. Sure. Just about all high-energy industries that don't use up limited resources are sustainable. The desalination itself is sustainable. That's a different question from where the plant buys power, or where it buys parts, or whether the employees use gasoline to get to work and back. There's nothing tying it to buying sustainable power or unsustainable power; that's a significantly different question and while it could fit in the article, it's by no means necessary for the article.
    - dredmorbius 10y ago
      That's verging on overt fallacy. Every multi-factor process has some limiting factor. Your overall capability is defined by that limiting factor (constraint). Ecology knows this as Leibig's Law of the Minimum. There's a finite energy flux available on Earth. Excluding nuclear, there are solar, geothermal, and tidal fluxes. Nuclear introduces fission (uranium, plutonium, breeder), or fusion (yet unproven: hydrogen). The only reasonably unconstrained energy sources might be breeder or fusion, and I'm not sure either is long-term viable for other reasons (too long to go into now, though waste / "hygiene factors" play large). Otherwise, solar is what we've got. 1 kW/m^2 surface flux, modulo capacity factor (0.3), spacing factor (~0.5), conversion efficiency (presently <0.2, single-layer max 0.47, infinite layer max, ~0.85). The present roughly 17 TW of power consumed by humans would requite a nothin-but-solar region 800 km on a side. Factor in increased energy for the 6 billion people not living in the US or EU, and increased energy demands of the 8 bilion people (7 presently, plus one more) who'd like to live at US-standard-of-living levels, and you're increasing demand significantly. 85 TW just for population and standard of living would require 3.1 million km^2 -- about a third of the land area of the United States, Australia, or the Sahara Desert. With nothing in it but solar plant. Wall to wall. Oh, and 1/5 of that needs replacing. Every. Single. Year. Solar panels, for numerous systemic reasons, degrade with time, and have about a 20 year effective life. (Research on extending panel life strikes me as more useful than increasing efficiency or massive cost reductions.) Keep in mind that there are other creatures on this planet and they've got their own demands for land use. We may rely on them in complex ways. If you're building more power plant capacity than you can sustain, any industry relying on that power won't be sustainable.

by abalone 10y ago

einhverfr 10y ago

One of my favorite takes on this topic is Clarke and Dawe's take on the Victoria desalination project[1] (the two are comedians). [1]https://www.youtube.com/watch?v=X_SrrylkIEc https://www.youtube.com/watch?v=X_SrrylkIEc

vacri 10y ago
It's a bit sad, though - the Victorian government was in a no-win situation with that one. A nine-year drought with the water reserves to a city of 4M people down to 15%? Something had to be done, and the common refrain of "drought will break next year" had been heard every year for the previous half-decade. The plant was over-expensive and should have been bought in a progressive manner rather than full-capacity-at-once, but Melbourne was actually in danger of running out of water. They joke in the video "why not build a dam where it's actually raining?", but the point was, there'd been barely any rain for a decade. There wasn't anywhere that fit that description (and Melbourne has tons of water reserves outside of long drought conditions). Of course, because Fate is an arsehole, they got the construction underway, and the next year the drought broke. If the drought hadn't broken, people wouldn't be so quick to condemn the desal plant...

aaron695 10y ago

> How sustainable is the power source? Oil (and such and such) will last a 100+ years and obviously won't destroy the planet in that time. I'd call that sustainable. And given it's just a "power source", at any time we could swap it out for X, Y, Z. Plus they specifically talk about efficiencies in the article? Not sure your point at all? I haven't seen huge drops in energy cost across the world? Electricity seems the same or more than the 1990s?

throwaway5752 10y ago
"Oil (and such and such) will last a 100+ years and obviously won't destroy the planet in that time." It is not at all obvious that it won't.
andrewjl 10y ago
Two words: climate change
- polotics 10y ago
  Yep. Three words: Black flag weather

Dylan16807 10y ago

They're quoting 58 cents for a thousand liters. Even if we pretend that is based on free power, we can add the cost of a solar plant and produce each thousand liters for under a dollar. So desalination is completely sustainable.

abalone 10y ago
That's like saying all high-energy industries are sustainable, if we assume sufficient solar build-out. That's a big if. We can't just assume this project is going to be powered sustainably. It's something the article should have explored.
- Dylan16807 10y ago
  > That's like saying all high-energy industries are sustainable, if we assume sufficient solar build-out. Sure. Just about all high-energy industries that don't use up limited resources are sustainable. The desalination itself is sustainable. That's a different question from where the plant buys power, or where it buys parts, or whether the employees use gasoline to get to work and back. There's nothing tying it to buying sustainable power or unsustainable power; that's a significantly different question and while it could fit in the article, it's by no means necessary for the article.
  - dredmorbius 10y ago
    That's verging on overt fallacy. Every multi-factor process has some limiting factor. Your overall capability is defined by that limiting factor (constraint). Ecology knows this as Leibig's Law of the Minimum. There's a finite energy flux available on Earth. Excluding nuclear, there are solar, geothermal, and tidal fluxes. Nuclear introduces fission (uranium, plutonium, breeder), or fusion (yet unproven: hydrogen). The only reasonably unconstrained energy sources might be breeder or fusion, and I'm not sure either is long-term viable for other reasons (too long to go into now, though waste / "hygiene factors" play large). Otherwise, solar is what we've got. 1 kW/m^2 surface flux, modulo capacity factor (0.3), spacing factor (~0.5), conversion efficiency (presently <0.2, single-layer max 0.47, infinite layer max, ~0.85). The present roughly 17 TW of power consumed by humans would requite a nothin-but-solar region 800 km on a side. Factor in increased energy for the 6 billion people not living in the US or EU, and increased energy demands of the 8 bilion people (7 presently, plus one more) who'd like to live at US-standard-of-living levels, and you're increasing demand significantly. 85 TW just for population and standard of living would require 3.1 million km^2 -- about a third of the land area of the United States, Australia, or the Sahara Desert. With nothing in it but solar plant. Wall to wall. Oh, and 1/5 of that needs replacing. Every. Single. Year. Solar panels, for numerous systemic reasons, degrade with time, and have about a 20 year effective life. (Research on extending panel life strikes me as more useful than increasing efficiency or massive cost reductions.) Keep in mind that there are other creatures on this planet and they've got their own demands for land use. We may rely on them in complex ways. If you're building more power plant capacity than you can sustain, any industry relying on that power won't be sustainable.