Desalination system could produce freshwater that is cheaper than tap water

Article doesn't mention what the unit does with the salt waste.

I support this 100%, but desalination presents a unique problem: what do we do with all the salt? Maybe the unit uses it for something, but otherwise it just miniaturizes a problem that we're already working on.

This sounds fantastic on its face, but I seem to keep on hearing about how desalination will solve all kinds of problems and we still have this particular problem.

The missing piece, it seems, is the will for it to be used as infra at scale. Meanwhile selling bottled water taken for free from public lands for several dollars a liter in single-use bottles remains a multi-billion dollar industry. (an industry, I might add, that is aggressive about lobbying to protect its interests)

cool, but the real cost of desalination is transporting the desalinated water upstream, which presumably would also need to be done here

SONOFABIT*H, I've been working on a project exactly like this with my friend for a couple years. Hella congrats they got it done and working first but damn :'( I was too slow.

Imma go sadly crush some bugles with my face stones now

All this stuff is like planning to colonize mars before we stop destroying earth. There is plenty of water if we just stop fucking pumping it all out and wasting it.

I feel like every week we hear about some huge breakthrough that is supposed to revolutionize clean drinking water technology and save the world, but nothing ever comes of it.

I know this stuff takes time to develop, and not every idea is going to work, but it would be nice if one of these things actually did pan out and start being useful to solve our drinking water issues.

Where's the cheaper part?

Permanently Deleted

Delete this before Nestle sees it.

“Could”. What kind of fucking title is this?

Either it does or it doesn’t.

The massic heat capacity of water is 4184 J⋅kg⁻¹⋅K⁻¹. To heat one 1 Liter (1 kg) of water from 30ºC to 100ºC it would take 4184×(100-30) = 2.929e5 J. We want 4 liters however, so we multiply that by 4 and get 2.929e5 J × 4 = 1,172e6 J To then turn that heated water into vapor it would require some more energy. The vaporization enthalpy of water is 4,066e4 J⋅mol⁻¹, and has a molar density of 1,80153e-2 kg⋅mol⁻¹(so 4 liters (4 kg) of water in moles would be 4 / 1,80153e-2 = 2,22033e2 mol), which means that to vaporize the four liters of water we would need 2,22033e2 × 4,066e4 = 9,028e6 J (I think I might have made a mistake here somewhere, because I don't think it would only need 8 times more energy to completely vaporize the water, compared to the amount of energy required to heat it, but I can't find the problem). So the total energy to heat and vaporize 30 ºC water would be 9,028e6 + 1,172e6 = 1.020e7 J

Let's take a 55x40x23 cm suitcase. And let's assume a solar irradiance of 1000 W⋅m⁻² (which is what this site says is a normal solar irradiance to be expected on a clear day on the equator). Let's assume three faces are exposed to the sun and all equally so (three faces receive 1000 W⋅m⁻² while the other three receive none, which would not happen since on a rectangular cuboid, like a suitcase, you can't have all three faces facing directly towards the sun). The box would be receiving (0.55×0.40+0.40×0.23+0.55×0.23)×1000 = 438.5 W, which means that over one hour (3600 s), it would receive 438.5×(3600) = 1,5786e6 J, which is less than the required 1.020e7 J (by almost an order of magnitude), so it wouldn't be possible to heat and vaporize 4 liters of water in an hour.

What am I missing?

‘Cheaper’….desalination eats a lot of power. This is causing a huge problem over a minor inconvenience.

We have destination where I live but the problem is this: the water often smells like fish. And it's very hard because they use so many chemicals.

I don't think desalination is the solution.