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Desalination is incredibly expensive. At this point, they aren't completely out of water, as the crisis continues desalination will become more viable (expensive or not, people need water to survive).



Desalination is expensive because of the cost of power, but what is being proposed is not just "we should desalinate", but is "Why don't we make better use of the power opportunities," such as a desalination plant with solar panels and/or generators for waves/tides. We could offset the electrical cost of desalination if the plants could help generate their own power. Why not pass water through turbines before desalination? There are tons of opportunities for refining the process, and it's just the initial cost that's large. Over time, the plant will pay for itself and if ever optimized, could actually provide power back to the grid.


Solar power is more expensive than fossil fuel power. The solution to "desalinization is too expensive" is not to say, "But what if we used a more expensive form of power to do the desalinization?"


Maybe for base load, but desalination can run intermittently during sunlit hours only. You only have to stay ahead on average..


The solution to "desalination is too expensive" is ALSO not to only use your desalination facility some of the time, and also when the price of energy is highest.


Solar is cheaper per watt in many parts of the world, assuming you don't care when you get those watts. You can build more solar capacity than what's needed during daylight hours in which case you can't sell the energy due to there being too much of it, so high price of energy becomes irrelevant.

(or: you can't build a large number of solar power plants without affecting the market price of electricity)


Ah, so now your plan to reduce the cost of desalinization is to build so many solar power plants that you literally have more energy than you can possibly sell during the highest demand parts of the day. Well, that sounds like a good cost reduction technique.

Oh, wait. No it doesn't.


Are we talking about water or costs?


> Desalination is expensive because of the cost of power, but what is being proposed is not just "we should desalinate", but is "Why don't we make better use of the power opportunities," such as a desalination plant with solar panels and/or generators for waves/tides.

The capital cost of that is the cost of the generators + the cost of the desalination plants, and the desalination still probably isn't, even with the drought, the most valuable use of the power once you've built the generators.

> We could offset the electrical cost of desalination if the plants could help generate their own power.

We couldn't offset the opportunity cost of using the power for desalination rather than other uses that way, obviously.

> Over time, the plant will pay for itself

If its a permanent drought, maybe. Otherwise, that's doubtful. If the water isn't worth the electricity now, its an operating loss on top of the capital costs.


> Why not pass water through turbines before desalination?

You spend a ton of energy pumping the seawater up to pressure, then you pass it through a turbine? Why on earth would you do that?


According to Wikipedia it's really cheap: http://en.wikipedia.org/wiki/Desalination#Economics


Rainwater is cheaper. IF you look at how much residential users pay, then yeah you see that desalinization would not break the bank, but most water is for farms and they get it by the acre-foot.


These plants seem to be self-sustaining (they even create extra energy) and can provide potable water from the oceans:

http://cleantechnica.com/2015/03/15/first-kind-wave-energy-f...




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