The trick is figuring out where they hid the battery…or is that perpetual motion machines?
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I would have imagined that however much pure water one pulls out of the planet’s oceans, putting the brine back would have an infinitesimally negligible effect. (But IANAGeographer/Hydrologist).
And then, the ice caps melting are diluting the salt levels anyway, so its a wash?
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If you’re not near the coast tossing that brine water would not be great, would only make sense for those that live right by the beach.
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Indeed - I guess I assumed that if one is desalinating, it is from seawater, so the sea would be available to dump the output back into. But I expect there are also non-coastal applications for this, where, as you say, that would be problematic.
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Where are you getting your salt water from if you’re not near the coast? Desalination is best done at or very near the source of salt water, as transporting fresh water is far easier and safer.
Disposing of brine at scale is still a massive and currently unsolved problem though - something as small as this won’t be much of a problem, but you don’t need a lot of brine waste dumped somewhere for salinity levels in the area to rise sufficiently to harm aquatic life, and it doesn’t disperse quickly by itself (unless you’re dumping it in a location with very strong currents, which is rather unlikely). The same issue largely applies to pumping it further out to sea through pipes, though harms are somewhat lessened if dump sites are well selected (but that also gets expensive quick). The only really harmless solution would be some sort of large scale brine dispersal system, but that would in turn be very resource intensive and practically difficult. Harvesting it for other uses would be better for the environment, but would cause all kinds of trouble with the existing salt manufacturing industry, and would likely be far more expensive than current sea salt production (simply from the need for new infrastructure and new production sites if nothing else).
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That and just the process of making the concrete weights is very energy intensive and typically has a big carbon footprint. Many experts question how long such blocks could last when constantly being moved and stacked in some of the “gravity battery” designs out there. So over the lifetime of the battery it’s not clear that you’d actually be reducing your carbon footprint with this device vs. using other energy sources. In comparison, pumped hydro storage is way more practical in areas where the terrain allows it.
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Thermal energy storage also has a lot of promise, both heated sand batteries as well as various forms of melted salt batteries (and I’m sure there are others). And it’s not very space or materials intensive, relatively cheap, and scales decently.
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They’re not claiming six liters per day, but six liters per hour!
The researchers estimate that if the system is scaled up to the size of a small suitcase, it could produce about 4 to 6 liters of drinking water per hour
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4 - 6 litres per hour is impressive, but using solar energy to distill water isn’t really new…
And if you have seawater and sunshine, generally you have both in abundance so just use more devices 'til have the hours per litre you require.
If you want to scale up to provide enough water for whole communities though, this isn’t really a practical solution.
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Bloody hell, misread that.
I would have been impressed with 6 litres a day.
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That thing does up to 2l/day though, and it looks like it is at least the size of a suitcase when inflated. Of course it also looks like it’s designed for simplicity of construction and use rather than peak performance, but that’s a far cry from 6l/hour nonetheless!
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Perhaps something valuable can be made from salt + sulphur? There’s huge piles of sulphur extracted from the Alberta tar sands oil (pic below is from ~22 years ago, so those piles are likely bigger now). Win win?
Why yes, I did fail high-school chemistry AND economics. But spelling. Stoopid autocorrect.
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Correct, eventually. The problem is at the point of discharge. Not unmanageable, but needs consideration when desalinating at scale.
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Thank you. Came here to ask this.
…and it has a wastewater problem.
So, you hope for it not to work? Oh, how dare you! Won’t you think of the children!
You serious? That guy?
On a more serious note, Stefan Vogel did some work on leaf shapes in plants catching condensation:
Vogel, S. & Müller-Doblies, U. 2011: Desert geophytes under dew and fog: the “curly-whirlies” of Namaqualand
(South Africa). – Flora 206: 3–31.
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Short aside: the important bit is, I think, the “other energy sources”. Because:
I think there should be some long-term experience available in the military? I’ve seen this principle applied in certain facilities which need as much uptime as possible. Had a tour of a radar station, e.g., where they had the whole ground plate spinning continuously, to the best of my knowledge, more or less continuosly.
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Likely not comparable - a setup like that would be a high precision, low friction thing, likely running on specially designed and well lubricated bearings (with a specific service life and on-time replacements). Gravity batteries mostly talk about lifting giant concrete blocks with a crane, stacking them high so that they can be lowered later on a wire connected to the rotor of a generator. The wear would be from the stacking action, which no matter how careful you are would be pretty hefty impacts on the concrete blocks (and of course the cumulative compressive stress on them as the pile gets higher unless you’re making this super expensive using some sort of giant support structure. It’s the type of idea people who don’t care about annoying stuff like “wind” or “earthquakes” get stuck on.
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Yeah, it’s the proposals like the one in the video below that I’m especially skeptical of. Basically constantly assembling and disassembling skyscraper-sized towers of giant, unmortared bricks. Just creating a foundation to support that much mass would be an incredible logistical challenge.
Like I mentioned earlier the energy that it takes to produce concrete means this could take a long time to break even, even if it worked.
- 1kg of concrete takes a little over 1,000,000 Joules of energy to produce.
- The potential energy of 1kg of mass raised to 100m of height is a little under 1000 Joules.
So with a perfectly efficient 100m tall crane you would need to stack and unstack that block more than 1000 times before it had stored and released the equivalent energy to produce it in the first place. (Or more times, if it is being stacked at a lower height.) And that’s not even generating any energy, it’s just evening out the energy that was generated by another process.
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Which is ridiculous, since everyone knows that the Nazi UFOs ran the Marconi engine developed at the Mars colony in 1953. I mean, until the zero-point models came out in the 1980s anyway.
Schauberger had a very difficult life and not all his work is necessarily worthy of respect, but he was a tremendously gifted man, who made significant contributions to understanding turbulence, water purification, and hydraulics. His social and environmental views were infused with a lot of mysticism, even more than those of Einstein or Tesla, and a lot of people can’t deal with that kind of complexity, they need everything to be black and white cartoons. Having a tiny bit of familiarity with his work because of my interest in leets and penstocks, I can see why the pictures here of the desalinator would immediately make someone think of Schauberger.
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Thanks, I hadn’t thought this through. I recently had someone mention gravity batteries in the context of spinning masses, so I had a bias towards those types.
@Otherbrother, thanks for the link, gonna catch up on this ideas.
Well, isn’t that supplied at no cost by the sun? 
Right. I’ll see myself out.
On the global scale, the effect of brine is indeed negligible. On the local scale, specifically local to where you’re dumping the brine back into the ocean, it can have serious environmental effects.
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