Cheap solar gives desalination its moment in the sun
Ever-cheaper solar power is a tailwind for the global energy transition. It can make energy intensive technologies more affordable. As a result, desalination is becoming a more popular option for providing drinking water to some of the driest areas of the world.
The logic of desalination is clear. Water is increasingly scarce as populations grow and climate change bites. Already, more than half of the global population experiences severe water scarcity for at least part of the year, says the World Health Organisation. This pits users against each other, as in Spain’s most recent drought.
Desalination taps an almost infinite resource — some 97 per cent of the world’s water is in seas and oceans. Costs have plummeted. Older, thermal plants, which used heat to turn salt water into steam, delivered potable water at more than $3 per cubic metre.
Graph: the price of desalinated water over time.
Since then, reverse osmosis technology — in which water is pushed through a membrane to remove salt, minerals and impurities — has taken over. Plants cost less to build — perhaps $400mn to purify 500,000 cubic metres per day, says Christopher Gasson of GWI. Including installation, a return on capital and operating costs, that translates to $0.30 per cubic metre of water.
Newer plants also need less energy — 2.6KWh per cubic metre — and are increasingly powered by cheap solar plants. The cheapest plant in the world gets energy at $0.025/KWh, or $0.07 per cubic metre.
Put that together and it explains how the Hassyan project in Dubai has promised desalinated water at just $0.37 per cubic metre. For reference, drinking water in London is priced at £1 per cubic metre.
At this sort of level, desalination becomes more affordable for dry, coastal areas, not just in the Middle East but also in Egypt, Algeria and Morocco, which are all building new plants.
Desalination has also become cheaper than building new infrastructure to transport water over long distances: the cut-off is roughly 500km according to Acciona, a major operator. As a result, the market for new plants is expected to grow by perhaps 8 per cent a year from now to 2030.
Of course, desalination is still unlikely to be the answer to the bulk of the global water crisis. Many areas of the world only face temporary or occasional water shortages, which spreads the capital costs of infrastructure over a much smaller volume of water. Agriculture, which accounts for 70 per cent of the world’s consumption, needs cheap water to produce affordable crops.
Yet, for all this, early movers in the desalination sphere, including Saudi Arabia’s ACWA power, Spain’s Acciona and France’s Veolia, have a clear advantage in a competitive race.
Despite your edits, I don’t see anything in the linked articles that suggests brine cannot be diluted or dissipated.
Not sure why you’re still insisting on this after your edit, since as several commentors have pointed out there’s no reason for you to dump it in a single localised area. Toxins and heavy metals can also be extracted, and might even be done so profitably (according to your own links, in fact).
The only point you might have so far is Israel, since they are using a small lake as their source of water, and can’t reasonably dilute the brine. However, with seawater desalination none of these issues apply.
Seawater desalination can have this Problem too, if they are not continously discharging polluted brine, I.e. run a batch process. I believe some japanese build desalinator is doing the sensible continous discharge, but cant be fucked to Google right now.
Then you didn’t read enough. Israel has the largest Desal operation in the world with their combined facilities, and they’ve still managed to cause issues every operating year for a decade. Whether it be pipeline leaks, transport issues, or not controlling the byproducts well enough when they dilute it back to the ocean. It’s just not sustainable, and prone to error at every step.
Whether you think feasibility is enough in the “can we do this?” way is irrelevant. You just can’t use this type of system to solve the entire world’s issues, because eventually the intake vs output becomes unmanageable, and it’s basic math to figure that out. Storing this stuff in a mountain like we do with toxic waste has the same implications, and then you’re just adding to the pile for future generations to deal with. Same with air pollution, nuclear waste, fertilizer runoff…etc.
Seriously, if people like you are what future generations are contending with in that this is “not my problem now, they’ll figure it out”, this planet is certainly fucking doomed.
What exactly does operational issues and equipment breakdown have to do with a technology being viable?
Pretty much everything in modern industrial processes are prone to error at every step. Somehow, we’ve figured out how to follow checklists and procedures and avoid blowing stuff up. Your statement implies incompetence among the operators more than anything else.
Nobody has EVER suggested this, and you’ve set up a strawman argument out of thin air.
I’ve been pointing out how and why the technology can operate. You’ve been resorting to strawmen arguments and ad hominem attacks.
“Can” is not the same as “should”.
I “can” shit in the sink instead of my toilet. Of course it will eventually get down to the sewer.
I “should” shit in my toilet, for obvious reasons.
If your argument is that we “should” do something just because we “can”, you’re not thinking much of the world around you, or the rest of the population you affect with your actions.
I’d thank you not to mischaracterise my statements. I’ve been pointing out how and why the technology is sustainable, contrary to your claims. You are now merely resorting to puerile, kindergarten level arguments.
And yet, you’ve provided zero documentation or study backing up such claims, while I’ve provided plenty in the negative to yours. You can find way more if you just search for it instead of relying on your uninformed instincts and position because you don’t work in the field. Sorry, I wasn’t about to link every damn thing on the Internet proving my point. I thought four was enough.
Would you like to start with Wikipedia?
https://en.wikipedia.org/wiki/Desalination#Environmental_concerns
It lists all the arguments you’ve made and how they can be addressed. You’re the one making extraordinary arguments. The onus is on you to prove it.
Wikipedia is a topical resource. It’s not the real world, friend. My links are the real world, and the real implications of that. Every link explains the same problems I’ve mentioned, so that is evidence. Everyone sees this, so why don’t you?
Ah, we’ve moved on to the ‘Do your own research!’ phase. Complete with a helping of ‘If your conclusions don’t match mine, you didn’t research enough’.
Can we pretend we’ve progressed through all the various fallacies already, and call it here?