Solar-powered desalination device wins MIT $100K competition(news.mit.edu)
news.mit.edu
Solar-powered desalination device wins MIT $100K competition
https://news.mit.edu/2022/100k-competition-nona-0516
157 comments
Slight correction
> Their prototype generates drinking water at a rate of 0.3 liters per hour, and requires only 20 watt-hours per liter.
So it takes 3+ hours to make a liter, using 20Wh.
> Their prototype generates drinking water at a rate of 0.3 liters per hour, and requires only 20 watt-hours per liter.
So it takes 3+ hours to make a liter, using 20Wh.
So? It's trivially paralleled, this isn't a case of 9 women making a baby in a month. Just run three devices, get 1 liter in 1 hour with 20 watts.
20 watts each -> 60 watts?
20 watt-hours per liter multiplied by .3 liters per hour equals 6 watts each.
thanks, read that too fast
Is it just me or does this kind of thing just feel so weird and out of place:
> "The researchers also created a smartphone app that can control the unit wirelessly and report real-time data on power consumption and water salinity."
> "The researchers also created a smartphone app that can control the unit wirelessly and report real-time data on power consumption and water salinity."
For version 2 they're adding themes for the social media icons
> Concentrated Brines
Like the ones NASA has on the shuttle https://www.nasa.gov/feature/new-brine-processor-increases-w... right?
Like the ones NASA has on the shuttle https://www.nasa.gov/feature/new-brine-processor-increases-w... right?
Lots of gold in that water too. Mostly salt tho
I figure there must be a lot of things in sea water that might be valuable, if only you could concentrate them. Or in brines that are extracted from underground, like how some lithium is currently mined if I understand correctly.
Key takeaways:
* Nona uses a technology developed in MIT’s Research Laboratory of Electronics that removes salt and bacteria from seawater using an electrical current
* “Because we can do all this at super low pressure, we don’t need the high-pressure pump [used in reverse osmosis], so we don’t need a lot of electricity,” says Crawford, who co-founded the company with MIT Research Scientist Junghyo Yoon
* The company has already developed a small prototype that produces clean drinking water
* The audience choice award went to Sparkle, which has developed a molecular dye technology that can illuminate tumors, making them easier to remove during surgery
* The MIT $100K is MIT’s largest entrepreneurship competition
* “Our device runs on less power than a cell phone charger.” The founders cited problems like tropical storms, drought, and infrastructure crises like the one in Flint, Michigan, to underscore that clean water access is not just a problem in developing countries
* The technology could also possibly be used for hydrogen production, oil and gas separation, and more
* “Our mission is to make portable desalination sustainable and easy,” said Nona CEO and MIT MBA candidate Bruce Crawford in the winning pitch, delivered to an audience in the Kresge Auditorium and online
If you want to see the others, please go here: https://www.mit100k.org/launch
* Nona uses a technology developed in MIT’s Research Laboratory of Electronics that removes salt and bacteria from seawater using an electrical current
* “Because we can do all this at super low pressure, we don’t need the high-pressure pump [used in reverse osmosis], so we don’t need a lot of electricity,” says Crawford, who co-founded the company with MIT Research Scientist Junghyo Yoon
* The company has already developed a small prototype that produces clean drinking water
* The audience choice award went to Sparkle, which has developed a molecular dye technology that can illuminate tumors, making them easier to remove during surgery
* The MIT $100K is MIT’s largest entrepreneurship competition
* “Our device runs on less power than a cell phone charger.” The founders cited problems like tropical storms, drought, and infrastructure crises like the one in Flint, Michigan, to underscore that clean water access is not just a problem in developing countries
* The technology could also possibly be used for hydrogen production, oil and gas separation, and more
* “Our mission is to make portable desalination sustainable and easy,” said Nona CEO and MIT MBA candidate Bruce Crawford in the winning pitch, delivered to an audience in the Kresge Auditorium and online
If you want to see the others, please go here: https://www.mit100k.org/launch
This is legitimately uplifting. I've lived without drinkable water on tap for just a few weeks, and its not a fun experience.
Huge props to MIT and the research team for this.
Huge props to MIT and the research team for this.
> Nona Desalination says it has developed a device capable of producing enough drinking water for 10 people at half the cost and with 1/10th the power of other water desalination devices.
Not sure if it is a coincidence or not but "Nona" means salty in Bengali[0].
[0]: https://en.wikipedia.org/wiki/Bengali_language
Not sure if it is a coincidence or not but "Nona" means salty in Bengali[0].
[0]: https://en.wikipedia.org/wiki/Bengali_language
Probably a coincidence, somewhere I saw the device name stylized as »no Na+«.
First place project is great! But can't help myself and not compare the second place with other projects that are mentioned and feel speachless..
Yeah... Such a great idea to have every company discussion validated and approved by an AI.
The winning team's research was previously discussed[1] a few weeks ago.
[1] https://news.ycombinator.com/item?id=31200793
[1] https://news.ycombinator.com/item?id=31200793
Exciting! This wouldn't help with problems like lead in the water, would it?
I think it’s meant to provide an emergency source of water for drinking.
You wouldn’t want to use this for a large population for a prolonged period of time because you’d have trouble disposing of all the salt waste.
Figuring out how to handle the salt byproduct is a critical part of long term desalination.
You wouldn’t want to use this for a large population for a prolonged period of time because you’d have trouble disposing of all the salt waste.
Figuring out how to handle the salt byproduct is a critical part of long term desalination.
How much salt are we talking? A large portion of the country coats all paved surfaces with it during and after every snow/freezing rain. Shut down the salt mines if need be.
Just contaminate the entire country with random substances. What could possibly go wrong?
I agree your perspective, but the salt could be cheaply tested at various stages for whatever contaminants you’re afraid of. How much testing do you think is done on the lettuce you eat? Or the beef you buy? Or the flame retardants in your carpet, clothing, flooring, and furniture? What about the bpa alternatives in all good grade plastics? What about Teflon’s and other forever chemicals? The answer is only as little as everyone can get away with because the people with authority don’t have the means to deal with their actual workload or the fallout of shutting down massive companies indefinitely. Ignorance ain’t bliss, but it may be better than knowing I’m powerless against the greedy fascists mortgaging the survivability of earth for yachts, drugs, and vanity today.
I don't see what the issue would be of just dumping it back into the ocean if you find no better use for it?
Maybe we can place the effluent at the base of a glacier so it buffers the fresh water coming off the melting glaciers and keeps the ocean running? /s
Can you pack it and sell it?
That’s a looooooot of salt, way more than you’re ever gonna use up through food, and it’s heavy. And corrosive.
1,000,000 humans require 4,000,000 liters of water daily. Seawater is 3.5% salt (35g/l), giving us 140,000,000g of salt. If we assume NaCl, with a density of 2.17g/cm3, that gives us 64,500,000 cm3 of salt, or 64.5 m3. I am getting a range of capacities on dump trucks, but somewhere on the order of 10m3 per truck. So 6-7 dump trucks dropping salt into the middle of nowhere. That does not sound like an infeasible problem for maintaining 1e6 humans?
Expecting Cunningham’s Law to show I goofed the math.
Expecting Cunningham’s Law to show I goofed the math.
I think your main issue is that the NaCl doesn't come out in a pure crystalline form. It's a higher concentrated brine but still contains an awful lot of water.
Nuts, that is an excellent point. I am failing to find the outflow concentration of salt, but you are correct that the output is likely to be only mildly concentrated (eg 7% salt). For all I know, it take an order of magnitude more energy to emit pure salt rather than a brine. Total amount of salt is not insurmountable, but the volume of output would be challenging quickly without enormous evaporation pools.
My understanding is some US salt flats are actually restored on annual basis to facilitate high speed racing on them. So if you didn't mind trucking it a very long distance, they'd be happy to have you dump it out there.
Humans require a lot more than 4L daily if you count sanitation, food production, and so on. But it’s still true that ultimately it’s not a lot of water if we wanted to put our minds to it.
You have 4 liters of water per person? That's what, only drinking?
Average household water use in 100-200 liters per day.
Average household water use in 100-200 liters per day.
[deleted]
Put it on a rocket ship and fly it into the sun of course.
While this is a nice project for emergency and remote uses, what we really need re: desalination in places like California (and other variable / dry climates) is large-scale desalination tied to opportunity power (such as curtailed grid power).
With each passing year there's going to be more and more solar on the grid, and it's going to be hard to soak up that power during the daytime peak. Desalination matches the solar supply curve perfectly: there's more water demand during the day, and there's also more water demand during the summer when there's also more sun. It's the ultimate dispatchable load.
With each passing year there's going to be more and more solar on the grid, and it's going to be hard to soak up that power during the daytime peak. Desalination matches the solar supply curve perfectly: there's more water demand during the day, and there's also more water demand during the summer when there's also more sun. It's the ultimate dispatchable load.
Do we really need expensive desalination in California? Domestic water use only accounts for 20% of demand and desalination seems unlikely to ever be cheap enough for agricultural use (the remaining 80%.)
Other than a few coastal places like Marin and Sonoma that aren't on the state water project I think the answer is no. The resulting water will be too expensive. It would be cheaper to pay farmers to stop growing inefficient and largely unnecessary crops (pasture grass, alfalfa) or to move to more efficient drip irrigation. As you said, the domestic use is so low and ag users wouldn't pay for desalination when there is actually a fairly sizable (although possibly dwindling) source of water available.
You could get a lot of mileage out of just cutting out that billionaire's almond groves. Or make him pay for his water; at last report, he was stealing it with a pipe stuck through the side of a canal dike.
I'm curious what your favorite alternative to alfalfa might be.
Most coastal communities in southern California don't even bother to reservoir off their water during rain events, instead letting it drain into the ocean. One major exception being Santa Monica which only uses 40% of it's water from up north unlike other communities which are 100% reliant on it.
Back of the envelope math suggests that based on average rainfall amounts per year a place like Ventura county could be entirely self-sufficient without any desalination plants.
Agriculture can also switch to drip feeding water instead of spraying which cuts usage by 90% without lowering yields.
There's a lot that can be done. We just need the political will to make it happen.
Having extra reservoirs can also support more natural vegetation and potentially actually create conditions for more rainfall further from the coast.
Back of the envelope math suggests that based on average rainfall amounts per year a place like Ventura county could be entirely self-sufficient without any desalination plants.
Agriculture can also switch to drip feeding water instead of spraying which cuts usage by 90% without lowering yields.
There's a lot that can be done. We just need the political will to make it happen.
Having extra reservoirs can also support more natural vegetation and potentially actually create conditions for more rainfall further from the coast.
> Do we really need expensive desalination in California? Domestic water use only accounts for 20% of demand and desalination seems unlikely to ever be cheap enough for agricultural use (the remaining 80%.)
If you like to eat, yes, you do. I still cannot fathom what distorted minds most transplants possess: California was and is an Ag state, it;s a fundamental part of it's culture it also feeds most of the US with its produce/fruit and exports it's surplus all around the World in surplus commodities.
Yes, stricter water preserving techniques are required for Ag, this recent budget surplus should go towards that as well as desalination to replenish aquifers and reservoirs/quarries after decades of an unsustainable population growth. This recent COVID exodus needs to go on for decades for the population to just return to the norms of the 70-80s.
You guys that write this kind of misinformed responses are so delusional, you cannot eat apps or drink code when you're hungry: and I can assure you will be the first to break when you haven't been fed for a few days or have to ration food/water since you've been accustomed to a lifestyle that simply doesn't reflect reality. And I highly doubt you can do any level of manual labour in order to feed yourself, either.
Get real, water conservation methods all around needs to be enforced BY EVERYONE! AG is guilty of exploiting loopholes when CA water laws were written to serve prospectors, and they should be taxed for over-useage and incentivize them with grants to utilize drip irrigation systems etc... but if you really want to solve this issue, which most of you won't agree to, is remove Farm subsidies: this will force farmers to cut down on these practices to make alfalfa or soy in the Central Valley for export to China that is only profitable because the State subsidies this horrific business model, it in turn will make food get even more expensive, which if you look at it in terms of net income is the historical norm: ~15% of total net income [0].
Food security is a matter of national security for a reason, it's used as a reliable weapon in warfare and has been a reason why most of humanity has gone to war in the first place, and if you like to keep civilization operating it's absolutely critical.
0: https://www.thevintagenews.com/2020/05/07/grocery-store-pric...
If you like to eat, yes, you do. I still cannot fathom what distorted minds most transplants possess: California was and is an Ag state, it;s a fundamental part of it's culture it also feeds most of the US with its produce/fruit and exports it's surplus all around the World in surplus commodities.
Yes, stricter water preserving techniques are required for Ag, this recent budget surplus should go towards that as well as desalination to replenish aquifers and reservoirs/quarries after decades of an unsustainable population growth. This recent COVID exodus needs to go on for decades for the population to just return to the norms of the 70-80s.
You guys that write this kind of misinformed responses are so delusional, you cannot eat apps or drink code when you're hungry: and I can assure you will be the first to break when you haven't been fed for a few days or have to ration food/water since you've been accustomed to a lifestyle that simply doesn't reflect reality. And I highly doubt you can do any level of manual labour in order to feed yourself, either.
Get real, water conservation methods all around needs to be enforced BY EVERYONE! AG is guilty of exploiting loopholes when CA water laws were written to serve prospectors, and they should be taxed for over-useage and incentivize them with grants to utilize drip irrigation systems etc... but if you really want to solve this issue, which most of you won't agree to, is remove Farm subsidies: this will force farmers to cut down on these practices to make alfalfa or soy in the Central Valley for export to China that is only profitable because the State subsidies this horrific business model, it in turn will make food get even more expensive, which if you look at it in terms of net income is the historical norm: ~15% of total net income [0].
Food security is a matter of national security for a reason, it's used as a reliable weapon in warfare and has been a reason why most of humanity has gone to war in the first place, and if you like to keep civilization operating it's absolutely critical.
0: https://www.thevintagenews.com/2020/05/07/grocery-store-pric...
"you cannot eat apps or drink code when you're hungry: and I can assure you will be the first to break when you haven't been fed for a few days or have to ration food/water since you've been accustomed to a lifestyle that simply doesn't reflect reality. And I highly doubt you can do any level of manual labour in order to feed yourself, either."
This is cathartic and fun to read - and it equally applies to bankers, and other highly paid wankers.
Our economy as a whole underpays and inderinvests in the foundamental things that allow advanced society to exist - as the whole climate crisis demobstrates.
This is cathartic and fun to read - and it equally applies to bankers, and other highly paid wankers.
Our economy as a whole underpays and inderinvests in the foundamental things that allow advanced society to exist - as the whole climate crisis demobstrates.
The Midwest is capable of growing all the alfalfa we need. Ending alfalfa alone would solve the water shortage for at least a decade. And it's mostly just exported to China.
I eat apps when I’m hungry
> I eat apps when I’m hungry
Kek, as a former cook I should have structured those 2 metaphors differently, but yeah... ok yeah you got me on the play on words. Well played.
Kek, as a former cook I should have structured those 2 metaphors differently, but yeah... ok yeah you got me on the play on words. Well played.
True, though there's a question of whether there will be demand to keep up those ag uses as water becomes more scarce generally (I could see it going either way).
Electricity is something like half of desalination's operational cost, and we're already in a situation where the price on the grid goes negative (or is curtailed) during solar peaks and more and more solar is being added to the grid each year. So power for desalination is going to be near free in the coming years. (Whereas for other less flexible loads, electricity isn't likely to get cheaper quickly, since we have to either have storage or use gas plants.)
Electricity is something like half of desalination's operational cost, and we're already in a situation where the price on the grid goes negative (or is curtailed) during solar peaks and more and more solar is being added to the grid each year. So power for desalination is going to be near free in the coming years. (Whereas for other less flexible loads, electricity isn't likely to get cheaper quickly, since we have to either have storage or use gas plants.)
The last desal plan in SoCal just got shot down ... the plant in my area was voted down not long ago as well. There needs to be a bit more suffering and research before most are going to agree to the clear negative aspects ... I love fishing and a clean Bay too. We, however, are gonna run out of water. By that time its going to be an entire California event in which the plants arent supplying just the local water districts but most of the state. At that point were just gonna eminent domain Fort Ord and build an effluent pipe half way to Kauai.
I don't know if we're truly going to run out of water or not, but there are many measures it would make sense to take before building desalination plants, such as recycling water and more efficient agricultural water use.
Agricultural use accounts for the overwhelming majority of water use in CA. I doubt Bay Area and LA residential faucets will go dry before water use is reformed. The rural areas are massively out-voted by the urban centers.
Not everything is reformable via public vote. Property rights and constitutional rights are largely on the side of the agricultural users.
Faucets will never go dry because human drinking water is a minuscule use. Some sprinklers and pools may go dry in times of drought
Faucets will never go dry because human drinking water is a minuscule use. Some sprinklers and pools may go dry in times of drought
Property rights are governed by laws. Legislatures can change laws.
We have a desal plant in Santa Barbara: https://www.santabarbaraca.gov/gov/depts/pw/resources/system...
> Do we really need expensive desalination in California?
It’s a good question, and it’s been discussed quite often in recent media sources for the past two weeks due to the rejection of the proposed Poseidon plant in Huntington Beach.
The honest truth is you could probably argue for both sides. Realistically, it’s cheaper and less environmentally harmful to promote non-desal measures, but not as easy to see quicker and observable benefits. The problem with the latest proposal was that it had a lot of problems, and the company behind it has a paper trail of small scale disasters in its wake (see the failure of the Tampa Bay facility, for example).
I personally believe that this is the kind of project that could benefit from a closer partnership between the government and private industry. From what I can tell, the technology is mature and feasible, but every time someone tries to design and implement it in the states, they seem to drop the ball.
I would be curious to see the record of success of other large scale projects outside the US. I’ve heard about the benefits and risks of the plants in the Middle East and elsewhere, but I don’t know the details.
It’s a good question, and it’s been discussed quite often in recent media sources for the past two weeks due to the rejection of the proposed Poseidon plant in Huntington Beach.
The honest truth is you could probably argue for both sides. Realistically, it’s cheaper and less environmentally harmful to promote non-desal measures, but not as easy to see quicker and observable benefits. The problem with the latest proposal was that it had a lot of problems, and the company behind it has a paper trail of small scale disasters in its wake (see the failure of the Tampa Bay facility, for example).
I personally believe that this is the kind of project that could benefit from a closer partnership between the government and private industry. From what I can tell, the technology is mature and feasible, but every time someone tries to design and implement it in the states, they seem to drop the ball.
I would be curious to see the record of success of other large scale projects outside the US. I’ve heard about the benefits and risks of the plants in the Middle East and elsewhere, but I don’t know the details.
Id imagine a lot of the other desal plants (esp. those in Saudi Arabia) are less than obligated to admit to their resource usage and waste products. Apparently desal is very energy intensive. OP pointed out using solar but I would like an equivalent of how many 400W solar panels does it take to make 1 gallon desal water.
No idea, but AMTA reports 2.5 to 3.5 kwh/ m3 (10-13 kwh/kgal). They write: "Based on nationwide data from the Energy Information Administration, a typical refrigerator average annual energy usage is 1,400-1,500 kwh. Using the average US water use per household of 100,000 gallons per year, the energy requirement for supplying desalinated water to a house in the US will be less than an old refrigerator, but the same as a newer, more efficient refrigerator power use."
My small desalination rig uses about 1200 watts and makes 30 gallons per hour. It cost me $3500. So it’s doable with 3 panels for this 2 person household.
I’d imagine a plant would benefit from economies of scale. Though these benefits could get eaten up by cost overruns. Frankly, it seems the hurdle in California is working through the people issues/concerns than technical problems.
It’ll be interesting to see the stats on this new desal technique when they have a product for sale.
I’d imagine a plant would benefit from economies of scale. Though these benefits could get eaten up by cost overruns. Frankly, it seems the hurdle in California is working through the people issues/concerns than technical problems.
It’ll be interesting to see the stats on this new desal technique when they have a product for sale.
1200 W for 30 gal/h works out to 10.6 Wh/L (or 38 kJ/L).
Yeah! California could fix the water issue by restricting agricultural use water. That way, California could finally kill off it's agricultural production. This will ensure farmers will move to other states and turn to the plentiful supply of hard drugs. This seems exactly what California will do. You would think California politicians might make a good decision -- EVEN by mistake once and while -- but NO. How is that train from LA going?
https://www.reuters.com/world/us/california-staff-report-rec...
https://www.reuters.com/world/us/california-staff-report-rec...
This is just "But think of the farmers!!!".
Across the US, farmers are not poor. By dint of being landowners, they are in fact some of the richest people around. See, e.g., this article: https://www.theatlantic.com/ideas/archive/2021/09/trump-amer... or this one: https://www.nytimes.com/2022/05/14/opinion/sunday/rich-happi....
Across the US, farmers are not poor. By dint of being landowners, they are in fact some of the richest people around. See, e.g., this article: https://www.theatlantic.com/ideas/archive/2021/09/trump-amer... or this one: https://www.nytimes.com/2022/05/14/opinion/sunday/rich-happi....
Exactly. They are loaded, especially from farm subsidies. On paper they are super rich. We should cut off their water, force them to pay taxes on their still operating farms, and sprinkle salt all over the land. California should shoot down the water desalination projects (like it has for 20 years) and punish it's citizenry.
"This will ensure farmers will move to other states"
This does not even make sence - Are they going to sell their farmland? To whom, other farmers? Are those other farnera not going to farm the famrland?
This does not even make sence - Are they going to sell their farmland? To whom, other farmers? Are those other farnera not going to farm the famrland?
I've posted about this on here before but the remaining 89% actually isn't just agriculture, though that is a Californians favorite scarecrow.
https://en.wikipedia.org/wiki/Water_in_California#Uses_of_wa...
> Water use in California is divided into approximately 51% for environmental uses, 39% agricultural use and 11% urban uses, though that varies considerably between regions and between wet and dry years.
https://en.wikipedia.org/wiki/Water_in_California#Uses_of_wa...
> Water use in California is divided into approximately 51% for environmental uses, 39% agricultural use and 11% urban uses, though that varies considerably between regions and between wet and dry years.
"Environmental" uses seems to mean they're just allowing the water to run naturally to maintain the environment. (This is the source Wikipedia cites: https://www.ppic.org/publication/water-use-in-california/). It's funny that they call that a use of water in California. If you remove that, then yes, agriculture uses 80% of the water.
Actually, it's more convoluted than that:
I'm unable to tell whether that's a tally for untapped water or if it's really meant to account for something meaningful.
The CFB does say that ag accounts for 80% of "human use".
Water that naturally flows into the state’s “wild and scenic” rivers, which are not connected to the state’s water system and can’t be under state and federal protections
Water required for maintaining fish and wildlife habitat within streams
Water that supports wetlands within wildlife preserves
Water needed to maintain water quality for agricultural and urban use
I'm unable to tell whether that's a tally for untapped water or if it's really meant to account for something meaningful.
The CFB does say that ag accounts for 80% of "human use".
I tried reading the wiki article and couldn't find an answer. Could someone explain to me what "environmental uses" is?
..also, water storage is fairly straightforward, so the water usage peak doesn't have to exactly track with the daily solar power production peak.
depending on how you build the storage, you could also use the excess water for power, no? Some sort of gravity battery setup.
Yep, it’s called pumped hydro: https://en.wikipedia.org/wiki/Pumped-storage_hydroelectricit...
I think it’s very promising/exciting as a method of smoothing out the demand curves of the electric grid. Plus, it’s fairly straightforward to modify existing dams/hydro infrastructure to have this capacity.
Since some dams are already used as water reservoirs for drinking/agriculture, this could be quite viable if the desalination can be done cheaply and efficiently at scale (not sure if this is even possible on the scales required for this idea to make sense, though).
I think it’s very promising/exciting as a method of smoothing out the demand curves of the electric grid. Plus, it’s fairly straightforward to modify existing dams/hydro infrastructure to have this capacity.
Since some dams are already used as water reservoirs for drinking/agriculture, this could be quite viable if the desalination can be done cheaply and efficiently at scale (not sure if this is even possible on the scales required for this idea to make sense, though).
Pumped hydro has been extremely effective in Australia since the mid 1960's. There's currently a project to extend the capacity of the Snowy Hydro scheme to soak up this extra transient renewable capacity.
https://www.snowyhydro.com.au/generation/the-snowy-scheme/
https://www.snowyhydro.com.au/generation/the-snowy-scheme/
That's cool -- I didn't know that! Imo, the more effective and cheaply we can store energy and smooth out supply/demand curves, the more attractive solar and wind becomes.
Perhaps one way of encouraging a "greener" grid is to first encourage the development of cheap energy storage solutions, and then letting the market figure out the best way to utilize such storage (rather than the other way around). Might lead to more efficient/creative green energy solutions.
Perhaps one way of encouraging a "greener" grid is to first encourage the development of cheap energy storage solutions, and then letting the market figure out the best way to utilize such storage (rather than the other way around). Might lead to more efficient/creative green energy solutions.
got get it up there ... places like Cali dont have a lot of rain that places itself up there and runoff is running out.
That's the point you can pump the water higher using excess renewable energy (in the event we get past 100% peak renewable power) to be used later when there's a deficiency. It's a fairly efficient method of time-shifting renewables without having to mine huge piles of lithium.
Pumped hydro if geography permits is very good storage method. Efficiency is not horrible, it is simple to ramp up and down. Technology is extremely mature. It scales pretty well. And as final bonus in some cases it can contribute to grid stability.
Yeah the biggest downside is the ecological impact of the flooding involved in creating a new hydro source. They could maybe look at retrofitting it onto an existing hydroelectric dam so it's not flooding a new area.
A hydro power reservoir doesn't need a watershed, so can have overwhelmingly less ecological impact.
It still needs volume to flood to hold the water though and unless we're building up artificially the cheap way to do that is to build fairly wide. All that area is habitat and covering it has an impact. In the end it's probably well worth it so long as we're not destroying rare habitats to do it but it is still destruction that has to be considered and weighed.
Pumping desalinated water up to Sierra Nevada reservoirs would take a hell of a lot of pipe. We use canals and rely on gravity to move water, today.
I wonder whether the most efficient way to get water to the Sierra Nevada reservoirs would be to pump ocean water onto the desert, and let evaporation take it from there. Siphoning from the ocean into Death Valley, you wouldn't even need to pump it.
I'm going to assume you mean "up there" as in northern cali -- if we could get some clean hydrogen/electric transport trucking it shouldn't be impossible to move it around either!
Nuclear power to the rescue (again! Lol) use excess heat from nuclear power generation and the water that gets steamed anyways for cooling and desalinate it. The brine problem can be solved by not desalinating endlessly but using desalination to create lakes and dump the brine in the desert where nuke waste is buried.
Nuclear power is, as always, overwhelmingly more espensive than the alternative, solar. We have a great deal of desert in California, with plenty of sunshine, and evaporating only when the sun is out is fine.
You wouldn't even need enclosed evaporation containers; let the wind carry the moisture to the mountains, raining into existing reservoirs.
You wouldn't even need enclosed evaporation containers; let the wind carry the moisture to the mountains, raining into existing reservoirs.
Mixing corrosive saline and nuclear waste storage facilities is probably not the best idea.
One of the big challenges: convincing people to drink water that was desalinated at a nuclear power plant.
We already have a pool of brine in the desert.
All of our fresh water comes from evaporation and precipitation. I'm curious if there have been attempts to increase evaporation as a means of producing water in areas with excess solar energy.
I know industrial plants use reverse osmosis, but is there somewhere experimenting with creating structures to encourage evaporation and then capturing the water vapor at scale? (Passively, I mean. I know we can just boil water at scale with expensive industrial systems.)
I know industrial plants use reverse osmosis, but is there somewhere experimenting with creating structures to encourage evaporation and then capturing the water vapor at scale? (Passively, I mean. I know we can just boil water at scale with expensive industrial systems.)
Planting lots of trees is a moderately successful way of combating desertification.
I know sea salt is produced by filling up big pools and letting the sun do its thing, but capturing the water is challenging.
Although come to think of it, existing greenhouse technology would work, "just" fill a greenhouse with a layer of water or let it mist, then capture the precipitation off the roof. I'm pretty sure it needs a way to passively cool the thing though. I'm also sure there's a lot of factors why this wouldn't work, probably due to scalability compared to alternatives like reverse osmosis, land use, etc.
Although come to think of it, existing greenhouse technology would work, "just" fill a greenhouse with a layer of water or let it mist, then capture the precipitation off the roof. I'm pretty sure it needs a way to passively cool the thing though. I'm also sure there's a lot of factors why this wouldn't work, probably due to scalability compared to alternatives like reverse osmosis, land use, etc.
Solar stills work by putting something that can be as simple as a sheet of clear plastic over a hole in the ground, and putting a bowl under the peak of the sheet. A greenhouse with a brackish pool and a way to collect the precipitation would be a scaled up version.
https://www.sciencedirect.com/topics/engineering/solar-still
https://duckduckgo.com/?q=solar+still&iax=images&ia=images
https://www.sciencedirect.com/topics/engineering/solar-still
https://duckduckgo.com/?q=solar+still&iax=images&ia=images
>I'm curious if there have been attempts to increase evaporation as a means of producing water in areas with excess solar energy.
I guess we'd yield far better results in the long term by investing to lower greenhouse gas emissions anywhere in the world. We're still building coal plants in 2022!
I guess we'd yield far better results in the long term by investing to lower greenhouse gas emissions anywhere in the world. We're still building coal plants in 2022!
Congratulations to Bruce & Team! Always exciting to see a classmate building cool stuff.
In the whole article there isn't a single photo of the device...
This is incredibly inefficient compared to existing desalinization devices. My boat has a watermaker that uses 4w/liter and it isn't even state of the art. This is 5x less efficient. It is also incredibly low volume.
There is novelty in the method, and in not using filter mediums. But those differences aren't going to matter if it isn't an order of magnitude more efficient. You could buy an inflatable evaporative device off amazon today to desalinate seawater that makes far more water with no electrical input at all.
I'm a bit saddened to see this show up on HN after it made the rounds on FB groups a month ago, where it was debunked. The world has fresh water problems and desalinization at scale with higher efficiency would be a huge unlock. That is exciting. But I'm not sure why this particular approach is getting attention given it underperforms so badly. Except maybe that the letters MIT and a lot of journalists that don't care as long as you clicked.
There is novelty in the method, and in not using filter mediums. But those differences aren't going to matter if it isn't an order of magnitude more efficient. You could buy an inflatable evaporative device off amazon today to desalinate seawater that makes far more water with no electrical input at all.
I'm a bit saddened to see this show up on HN after it made the rounds on FB groups a month ago, where it was debunked. The world has fresh water problems and desalinization at scale with higher efficiency would be a huge unlock. That is exciting. But I'm not sure why this particular approach is getting attention given it underperforms so badly. Except maybe that the letters MIT and a lot of journalists that don't care as long as you clicked.
This device was discussed earlier on HN and that article goes a little further into the design decisions for the device. (1) The focus is not efficiency or volume. It's compact, portable, robust, maintenance free. No filters, no high pressure components, suitcase size, able to use brackish water. They are not trying to solve industrial scale efficient desalination. They are trying to solve small scale portable desalination. You are measuring them against metrics they're not trying to achieve and it's no surprising they fail at this test.
(1) https://news.ycombinator.com/item?id=31200793, also linked in the article for this post.
(1) https://news.ycombinator.com/item?id=31200793, also linked in the article for this post.
Not to mention that the perspective siliconescapee boils down to "You could buy X off amazon today" which is not even possible for loads of people, as Amazon doesn't operate in many countries, and there are plenty of countries where Amazon doesn't even ship to. Then we have the 10% of people who live in poverty and wouldn't be able to afford ordering it anyways. Those are the groups that would be most helped by a device with these characteristics as well (easy maintenance and low ongoing cost).
But this device has the exact same problem you're describing, is less efficient, costs more and requires power. Novelty is the only upside
The only device I could find on Amazon that fits the description of an inflatable desalination device is https://www.amazon.com/Aquamate-Solar-Emergency-Purification... and it reportedly produces between 0.5 and 2 liters of water per day. That’s great if you have none, but the device being discussed here produces substantially more. So it’s not just a novelty thing.
Efficiency is less important in scenarios like tropical storms, drought, and infrastructure crises, or places where common western infrastructure is non-existent. Costs are also less important as they are cheaper over time as the costs of maintenance becomes lower. Places lacking infrastructure are also helped by outside organizations who donate knowledge and equipment. Considering that this device can be solar-powered (and these bespoke areas where infrastructure is non-existing generally are _very_ sunny), requiring power seems like a lesser problem.
But what are the use cases for a device that filters 0.3L of water an hour using 20W - that's still a fair amount of electricity?
There are many ways to use the sun to desalinate that seem more appropriate to getting drinking water to humans in poor parts of the world.
For example, this is another MIT project: https://news.mit.edu/2022/solar-desalination-system-inexpens...
There are many ways to use the sun to desalinate that seem more appropriate to getting drinking water to humans in poor parts of the world.
For example, this is another MIT project: https://news.mit.edu/2022/solar-desalination-system-inexpens...
According to them, their prototype does use 20Wh per liter and produces 0.3 liters per hour. It’s not 20Wh per 0.3 liters. That’s USB charger level of electricity, my 100 EUR foldable solar charger produces more on a good day.
The interesting part about this is probably that even the prototype is fairly compact and weighs like 10kg and that they claim to be able to achieve that with brackish water. If they can prove that it’s as robust as claimed, that sounds like an interesting technology.
The interesting part about this is probably that even the prototype is fairly compact and weighs like 10kg and that they claim to be able to achieve that with brackish water. If they can prove that it’s as robust as claimed, that sounds like an interesting technology.
Uhh just letting you know a device that uses solar energy is not maintaince free and saying that it is would be naive at best and misinformative at worst. It's an even bigger problem in countries where accessibility for such parts does not exist or the expertise to maintain such equipment. In reality a project like this is rather useless and after a few years of use if it ever received any it would belong in the trash.
But that's what most hackathons are in reality anyways.
But that's what most hackathons are in reality anyways.
The device needs power, but solar is not a requirement. But you’re correct, nothing is ever absolutely maintenance free, especially if it contains moving parts.
However, their envisioned use case is not “helicopterdump across the desert” but very specific use cases, often for people with technical skills:
> This could enable the unit to be deployed in remote and severely resource-limited areas, such as communities on small islands or aboard seafaring cargo ships. It could also be used to aid refugees fleeing natural disasters or by soldiers carrying out long-term military operations.
Whether they succeed in making a device useful these cases is a good question, but I consider it pretty dismissive that you characterize a 10 year research effort as “most hackathons”
However, their envisioned use case is not “helicopterdump across the desert” but very specific use cases, often for people with technical skills:
> This could enable the unit to be deployed in remote and severely resource-limited areas, such as communities on small islands or aboard seafaring cargo ships. It could also be used to aid refugees fleeing natural disasters or by soldiers carrying out long-term military operations.
Whether they succeed in making a device useful these cases is a good question, but I consider it pretty dismissive that you characterize a 10 year research effort as “most hackathons”
I see the majority of these grant styled competitions as just this, hackathons. Besides the prestige involved the majority of these inventions often prove to have little to no value to often not even doing as advertised. The way we incentive academic funding and research is backwards and often more than not broken at its fundamental core. It's compelled further due to these research rings broken into their own hierarchical technocratic groups.
Without knowing more about this device it's a bit hard to make a true comparison to existing marine RO devices but there are a few reasons I've been following with (skeptical) interest:
- Low volume - RO devices don't scale down well. The Katadyn 40E is the smallest watermaker I can find and it produces 6l/h. This is an insane amount of water that I have no use for. 10l a day would be enough for two people. Unfortunately there aren't cheaper and lighter options available.
- Storage - No pickling would be really nice.
- Membrane - Not needing to replace membranes would also be nice.
- Efficiency - I don't care too much about efficiency because most of the time during the day we have plenty of power from 400W of solar panels sized for days and days of cloud. That said, smaller RO devices also have poorer efficiency, e.g. 9Wh/l in the 40E. Other results in the literature suggests there could be plenty of room left to improve in efficiency from the MIT prototype.
Depending on cost, I think there's a niche for something that addresses the lower end of the market in watermakers.
- Low volume - RO devices don't scale down well. The Katadyn 40E is the smallest watermaker I can find and it produces 6l/h. This is an insane amount of water that I have no use for. 10l a day would be enough for two people. Unfortunately there aren't cheaper and lighter options available.
- Storage - No pickling would be really nice.
- Membrane - Not needing to replace membranes would also be nice.
- Efficiency - I don't care too much about efficiency because most of the time during the day we have plenty of power from 400W of solar panels sized for days and days of cloud. That said, smaller RO devices also have poorer efficiency, e.g. 9Wh/l in the 40E. Other results in the literature suggests there could be plenty of room left to improve in efficiency from the MIT prototype.
Depending on cost, I think there's a niche for something that addresses the lower end of the market in watermakers.
As someone who uses a kitchen more than a galley (i.e. I'm a land crab), I had to look up if "pickling" had a special meaning here.
It turns out to be kinda true, nobody is putting components of their watermaking system [1] in acidic solution for preservation and flavor, but they are putting them in sodium metabisulphite solution and that chemical seems to be useful for disinfecting and so on [2].
[1]: https://www.openoceanwatermakers.co.nz/pickling-your-system....
[2]: https://en.wikipedia.org/wiki/Sodium_metabisulfite
It turns out to be kinda true, nobody is putting components of their watermaking system [1] in acidic solution for preservation and flavor, but they are putting them in sodium metabisulphite solution and that chemical seems to be useful for disinfecting and so on [2].
[1]: https://www.openoceanwatermakers.co.nz/pickling-your-system....
[2]: https://en.wikipedia.org/wiki/Sodium_metabisulfite
If you can lower the transmembrane pressure you will get less output for less power and no fouling of the membrane. The economics of consumer choice drive design towards higher outputs and fouling.
Not using filters is huge! RO watermakers are really sensitive to poor quality water. Algae from last year's heat wave knocked out a lot of watermakers in Pacific waters.
From the paper
> The portable system desalinates brackish water and seawater (2.5−45 g/L) into drinkable water (defined by WHO guideline), with the energy consumptions of 0.4−4 (brackish water) and 15.6−26.6 W h/L (seawater), respectively.
So it consumes 26Wh/L turning nasty lowtide into drinkable water with no filter.
A 300W solar panel could then produce 10L of water per hour for probably 5 hours a day. 50L a day per panel. That is amazing!
> The portable system desalinates brackish water and seawater (2.5−45 g/L) into drinkable water (defined by WHO guideline), with the energy consumptions of 0.4−4 (brackish water) and 15.6−26.6 W h/L (seawater), respectively.
So it consumes 26Wh/L turning nasty lowtide into drinkable water with no filter.
A 300W solar panel could then produce 10L of water per hour for probably 5 hours a day. 50L a day per panel. That is amazing!
I don't know why some people are so obsessed with efficiency. Efficiency is, at best, one attribute of many which make something practical. We have had engines that are 50% thermally efficient for decades now, but no automaker has attempted to produce them because they are impractical in hundreds of other ways.
Not only would I buy this for my boat, but I would replace my more efficient spectra watermaker with it. Less noise and less maintenance are massive advantages.
Not only would I buy this for my boat, but I would replace my more efficient spectra watermaker with it. Less noise and less maintenance are massive advantages.
Right. Panels are so cheap now that, unless you are limited in how many panels you can physically install, lower efficiency just means another panel. Even then, maybe you cant a pair of them in place of one so one picks up morning light, and the other afternoon.
Yea.
- "This energy storage is only 30% efficient".
- "Yes but it's dirt cheap and so is solar peak power."
- "This energy storage is only 30% efficient".
- "Yes but it's dirt cheap and so is solar peak power."
> watermaker that uses 4w/liter
I think you have a typo there, but I am not sure what you mean. Maybe 4Wh/liter? (Knowing nothing about desalination, that sounds low, though)
I think you have a typo there, but I am not sure what you mean. Maybe 4Wh/liter? (Knowing nothing about desalination, that sounds low, though)
Yes, this device (first I found from google) produces 100L/hour using 400 Watts
https://www.nauticexpo.com/prod/schenker/product-23417-55567...
https://www.nauticexpo.com/prod/schenker/product-23417-55567...
Seems about right, the Katadyn PowerSurvivor 40E/12 V mentioned in another comment is 12 V, 4 A and 5.7 l/h, i.e. 8.4 Wh/l.
I wonder how much energy it takes to make the RO membranes.
I'd imagine that most beachfront properties have basically unlimited water, but are instead throttled by electricity costs.
Output water vs input water efficiency (20% in this case? 1-liter output from 5-liters input saltwater) matters in some cases, but not others. Since we all live in different terrains and locations, some inventions will be useful in some areas, while other inventions are useful in others.
Output water vs input water efficiency (20% in this case? 1-liter output from 5-liters input saltwater) matters in some cases, but not others. Since we all live in different terrains and locations, some inventions will be useful in some areas, while other inventions are useful in others.
You can imagine that, but a solar panel is cheap if it delivers 50L/day.
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If it doesn't use filter mediums, where does the salt and contaminants go?
Even devices that use Reverse Osmosis usually don't aim to catch all contaminants in the filter - they use a membrane/filter to separate the clean water output from a waste water stream that contains the contaminants/salts in higher concentration. This device effectively tries to replace the filter/membrane with an electrical current:
From https://news.mit.edu/2022/portable-desalination-drinking-wat...:
> their unit relies on a technique called ion concentration polarization (ICP), which was pioneered by Han’s group more than 10 years ago. Rather than filtering water, the ICP process applies an electrical field to membranes placed above and below a channel of water. The membranes repel positively or negatively charged particles — including salt molecules, bacteria, and viruses — as they flow past. The charged particles are funneled into a second stream of water that is eventually discharged.
From https://news.mit.edu/2022/portable-desalination-drinking-wat...:
> their unit relies on a technique called ion concentration polarization (ICP), which was pioneered by Han’s group more than 10 years ago. Rather than filtering water, the ICP process applies an electrical field to membranes placed above and below a channel of water. The membranes repel positively or negatively charged particles — including salt molecules, bacteria, and viruses — as they flow past. The charged particles are funneled into a second stream of water that is eventually discharged.
Down the drain.
[deleted]
I don't get it. Survival books show how to make a solar still with a plastic tarp, cup, straw, some rocks, and a hole in the dirt.
Solar stills can be simpler or far more complex than that, too. One design's just a milk jug and some aquarium tubing. Others are shed-sized or barn-sized construction projects.
https://news.ycombinator.com/item?id=31422582
https://news.ycombinator.com/item?id=31422582
How much water does that produce, and how much human labor must go into collecting it, and how well does it work in windy or cold conditions?
> How much water does that produce
Depends on how big it is, and the amount of sunshine
> how much human labor must go into collecting it
That's what the straw and cup is for. You put your lips around the straw and suck.
> how well does it work in windy or cold conditions
As well as evaporation works on windy or cold days. It won't work when it's raining, but then you wouldn't need it when it's raining.
BTW, why would wind affect it?
Depends on how big it is, and the amount of sunshine
> how much human labor must go into collecting it
That's what the straw and cup is for. You put your lips around the straw and suck.
> how well does it work in windy or cold conditions
As well as evaporation works on windy or cold days. It won't work when it's raining, but then you wouldn't need it when it's raining.
BTW, why would wind affect it?
A good survival book will also tell you that just one of those won't produce enough water for one person to survive on.
You can make more than one. You can make a larger one.
[deleted]
Certainly more exciting than the second place prize
>Inclusive.ly can scan a range of communications and make suggestions for improvement. The algorithm can detect discrimination, microaggression, and condescension, and the founders say it analyzes language in a more nuanced way than tools like Grammarly.
>The company is currently developing a plugin for web browsers and is hoping to partner with large enterprise customers later this year. It will work with internal communications like emails as well as external communications like sales and marketing material.
>Inclusive.ly can scan a range of communications and make suggestions for improvement. The algorithm can detect discrimination, microaggression, and condescension, and the founders say it analyzes language in a more nuanced way than tools like Grammarly.
>The company is currently developing a plugin for web browsers and is hoping to partner with large enterprise customers later this year. It will work with internal communications like emails as well as external communications like sales and marketing material.
That’s horrifying.
I think it is fine as long as it works same way as grammarly. You don’t want lose customer becouse you sounded like ass on email. Otherhand running this kinda solution at corporate slack or all outbounding messages mass censorship way sounds horrible.
If you’re afraid of your employees’ behavior around customers, you need to look at your HR hiring practices, not to Big Brother.
This is the kind of stuff that will cause good prospects to avoid ever applying to your company. Nobody wants to be second-guessed by a robot overlord (proof: Clippy).
This is the kind of stuff that will cause good prospects to avoid ever applying to your company. Nobody wants to be second-guessed by a robot overlord (proof: Clippy).
>Nobody wants to be second-guessed by a robot overlord (proof: Clippy).
People in the Rust community love clippy.
https://github.com/rust-lang/rust-clippy
People in the Rust community love clippy.
https://github.com/rust-lang/rust-clippy
That's assuming the employees will even be aware it is installed. It seems like this could easily be integrated into silent worker surveillance.
Mandatory link to real life story of something similar: https://www.reddit.com/r/LateStageCapitalism/comments/tev0ln...
“We make our tools and then our tools make us”. One can see the possibly good (or commercial) intent in this - but it also creates the realisation for the thought police to be inserted into AI. A relevant quote from my clippings:
"we have become so deeply habituated to the traditions of written language – our minds are quite literally shaped by them, like a gourd that is grown into a mould […]”.
"we have become so deeply habituated to the traditions of written language – our minds are quite literally shaped by them, like a gourd that is grown into a mould […]”.
I mean a lot of people aren't even aware they are, for example, being condescending - very common in e.g. HN comment threads. I'm sure this comment could be construed as condescending as well for that matter.
I'm not a fan in the same way as I'm not a fan of Grammarly. I just don't like things intefering with my flow.
However, you have to hand it to Incluse.ly. it sounds like the perfect dynamic to trigger all manner of macroaggressive neurons in the anti-woke .... 'bEcAuSeeee the wOke sCarEy mEEEEE!!!!!!"
Hmmm, I need to tone down my microagressions. My apologies to all concerned.
However, you have to hand it to Incluse.ly. it sounds like the perfect dynamic to trigger all manner of macroaggressive neurons in the anti-woke .... 'bEcAuSeeee the wOke sCarEy mEEEEE!!!!!!"
Hmmm, I need to tone down my microagressions. My apologies to all concerned.
[deleted]
Why are there so many water from x devices from MIT. Water from air, water from salt water etc. Is this all they do lol? Is there a group of people responsible?
Because it's a continual issue in the world, perhaps?
Yes. There's government money for "water and sanitation issues". NGO money too, but most of that is government money.
All of which issues have conventional solutions, but it's hard to assert you have a breakthrough with an incremental improvement to conventional solutions. And most of the time, deep incremental improvements require a lot of practical domain knowledge of the sort academics and especially their graduate students don't have.
You can probably still win an award for proposing using a lawn roller, as described in U.S. patent 1538550, filed in 1924, for transporting water in developing countries. If you're the right sort of person. More than one person has.
Actually figuring out how to bring sewers and water treatment and indoor plumbing to people in developing nations, that's too hard, too much like work, undeserving of your unique genius.
All of which issues have conventional solutions, but it's hard to assert you have a breakthrough with an incremental improvement to conventional solutions. And most of the time, deep incremental improvements require a lot of practical domain knowledge of the sort academics and especially their graduate students don't have.
You can probably still win an award for proposing using a lawn roller, as described in U.S. patent 1538550, filed in 1924, for transporting water in developing countries. If you're the right sort of person. More than one person has.
Actually figuring out how to bring sewers and water treatment and indoor plumbing to people in developing nations, that's too hard, too much like work, undeserving of your unique genius.
$100k? Most SV engineers could self-fund that. Why not make it $1m+?
Because it is a school project and not subject to any realistic assessment of commercial viability or innovation.
> The winner of this year’s MIT $100K Entrepreneurship Competition is commercializing a new water desalination technology.
> The company has already developed a small prototype that produces clean drinking water. With its winnings, Nona will build more prototypes to give to early customers.
> The company plans to sell its first units to sailors before moving into the emergency preparedness space in the U.S., which it estimates to be a $5 billion industry. From there, it hopes to scale globally to help with disaster relief. The technology could also possibly be used for hydrogen production, oil and gas separation, and more.
I think it is a bit beyond just being a school project (and I sincerely wish them all the best).
> The company has already developed a small prototype that produces clean drinking water. With its winnings, Nona will build more prototypes to give to early customers.
> The company plans to sell its first units to sailors before moving into the emergency preparedness space in the U.S., which it estimates to be a $5 billion industry. From there, it hopes to scale globally to help with disaster relief. The technology could also possibly be used for hydrogen production, oil and gas separation, and more.
I think it is a bit beyond just being a school project (and I sincerely wish them all the best).
Just about every engineering school has one of these. They put together a poster and business plan that said what they want to do.
https://news.mit.edu/2022/portable-desalination-drinking-wat...
20 watt hours per liter of water seems to be the important number.
I wonder if this system would also work for concentrating brines, if one's goal wasn't to produce clean water but rather extract certain valuable minerals, like lithium?