To make twice as much water you may need to either install a set of batteries to run at night, or install twice as much RO hardware to run during the day. Whichever's cheaper.
I made a comment with regards to this a while ago [1]. I'll repeat it here as I think it is relevant:
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I’ve heard on the grapevine that facilities are now being designed which work at under 100% capacity in order to soak up excess/cheap power.
I believe this is coming about because: 1) the high cost of power and presence of sporadically cheap power makes it economically viable, and 2) designing equipment with lower duty cycles can actually provide substantial cost savings. Ie a facility which only runs 50% of the time is much cheaper to build & run than once which runs 100% of the time.
Because you're likely going to be able to collect more energy than you can immediately use. That makes it effective to do so you can run the desalination even when the sun is down.
The question is if you could build and operate a smaller plant to run at 100% capacity at all times which includes energy storage for less money.
You either have losses in:
* Underutilized solar generation
* Underutilized plant capacity
* Overhead of energy storage
Design your system to minimize that cost. Engineering systems of all sorts are full of this kind of optimization problem: "Should I add a subsystem to recover loss x?" There is always more you can do to recover losses, but each extra system you add suffers diminishing returns a little more.
DenisM|6 years ago
adamcharnock|6 years ago
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I’ve heard on the grapevine that facilities are now being designed which work at under 100% capacity in order to soak up excess/cheap power.
I believe this is coming about because: 1) the high cost of power and presence of sporadically cheap power makes it economically viable, and 2) designing equipment with lower duty cycles can actually provide substantial cost savings. Ie a facility which only runs 50% of the time is much cheaper to build & run than once which runs 100% of the time.
Sorry I cannot cite sources right now.
[1]: https://news.ycombinator.com/item?id=18929542
baybal2|6 years ago
simcop2387|6 years ago
colechristensen|6 years ago
You either have losses in:
* Underutilized solar generation
* Underutilized plant capacity
* Overhead of energy storage
Design your system to minimize that cost. Engineering systems of all sorts are full of this kind of optimization problem: "Should I add a subsystem to recover loss x?" There is always more you can do to recover losses, but each extra system you add suffers diminishing returns a little more.