MIT Researchers Build Solar-Powered Low-Cost Drinking Water Desalination System (mit.edu) 18
MIT engineers have built a solar-powered desalination system that "ramps up its desalting process and automatically adjusts to any sudden variation in sunlight, for example by dialing down in response to a passing cloud or revving up as the skies clear."
While traditional reverse osmosis systems typically require steady power levels, "the MIT system requires no extra batteries for energy storage, nor a supplemental power supply, such as from the grid." And their results were pretty impressive: The engineers tested a community-scale prototype on groundwater wells in New Mexico over six months, working in variable weather conditions and water types. The system harnessed on average over 94 percent of the electrical energy generated from the system's solar panels to produce up to 5,000 liters of water per day despite large swings in weather and available sunlight... "Being able to make drinking water with renewables, without requiring battery storage, is a massive grand challenge," says Amos Winter, the Germeshausen Professor of Mechanical Engineering and director of the K. Lisa Yang Global Engineering and Research Center at MIT. "And we've done it."
The system is geared toward desalinating brackish groundwater — a salty source of water that is found in underground reservoirs and is more prevalent than fresh groundwater resources. The researchers see brackish groundwater as a huge untapped source of potential drinking water, particularly as reserves of fresh water are stressed in parts of the world. They envision that the new renewable, battery-free system could provide much-needed drinking water at low costs, especially for inland communities where access to seawater and grid power are limited...
The researchers' report details the new system in a paper appearing in Nature Water. The study's co-authors are Bessette, Winter, and staff engineer Shane Pratt... "Our focus now is on testing, maximizing reliability, and building out a product line that can provide desalinated water using renewables to multiple markets around the world," Pratt adds. The team will be launching a company based on their technology in the coming months.
This research was supported in part by the National Science Foundation, the Julia Burke Foundation, and the MIT Morningside Academy of Design. This work was additionally supported in-kind by Veolia Water Technologies and Solutions and Xylem Goulds.
Thanks to long-time Slashdot reader schwit1 for sharing the news.
While traditional reverse osmosis systems typically require steady power levels, "the MIT system requires no extra batteries for energy storage, nor a supplemental power supply, such as from the grid." And their results were pretty impressive: The engineers tested a community-scale prototype on groundwater wells in New Mexico over six months, working in variable weather conditions and water types. The system harnessed on average over 94 percent of the electrical energy generated from the system's solar panels to produce up to 5,000 liters of water per day despite large swings in weather and available sunlight... "Being able to make drinking water with renewables, without requiring battery storage, is a massive grand challenge," says Amos Winter, the Germeshausen Professor of Mechanical Engineering and director of the K. Lisa Yang Global Engineering and Research Center at MIT. "And we've done it."
The system is geared toward desalinating brackish groundwater — a salty source of water that is found in underground reservoirs and is more prevalent than fresh groundwater resources. The researchers see brackish groundwater as a huge untapped source of potential drinking water, particularly as reserves of fresh water are stressed in parts of the world. They envision that the new renewable, battery-free system could provide much-needed drinking water at low costs, especially for inland communities where access to seawater and grid power are limited...
The researchers' report details the new system in a paper appearing in Nature Water. The study's co-authors are Bessette, Winter, and staff engineer Shane Pratt... "Our focus now is on testing, maximizing reliability, and building out a product line that can provide desalinated water using renewables to multiple markets around the world," Pratt adds. The team will be launching a company based on their technology in the coming months.
This research was supported in part by the National Science Foundation, the Julia Burke Foundation, and the MIT Morningside Academy of Design. This work was additionally supported in-kind by Veolia Water Technologies and Solutions and Xylem Goulds.
Thanks to long-time Slashdot reader schwit1 for sharing the news.
Re: What do they plan on doing with the waste? (Score:2)
Re: What do they plan on doing with the waste? (Score:2)
Use the salt for... You know ... Salt production?
There's millions of tonnes of salt produced all over the planet, for varied uses every year.
Re: (Score:2)
I was wondering how long it would take for the first complaint about the saline run-off. I sure did not expect it to be the first ;)
Salt, in and of itself, is not toxic. The human body uses chemical ions, sodium & chlorine (potassium is another along with magnesium & phosphorus), that can be combined to make a "salt" molecule.
The problem comes down to the volume of waste and what form it will take.
If it is saline waste, perhaps it could be pumped into nearby settling ponds placed on arid unusable land. Nothing of value to humans would grow in such a saline environment; ok, some form of bacteria MIGHT grow in it. Allow the water
Re: (Score:2)
Re: (Score:2)
There's almost certainly some useful application for it.
Farming artisanal Fleur de sel?
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Does it have to use solar panels? Plants do it. AI will probably solve this problem some day. How to make a machine that converts maximum sunlight, minimum external resources, and desalinates water into drinking water?
AI came up with the following ideas:
- Photothermal Desalination System: photothermal (such as carbon-based materials, graphene oxide, or hydrogels) that efficiently absorb sunlight and convert it into heat, using the heat to evaporate water.
- Phase Change with Capillary Action: Use materials
Huh? (Score:2)
Re: (Score:2)
You needed to RTFS:
traditional reverse osmosis systems typically require steady power levels
Solar power is not steady. They figured out how to make the desalination process adjust to the lack of steady power. No batteries either. Just solar panels.
It's all there. You can safely skip TFA like the rest of Slashdot.
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I wish somebody could set up aluminum smelting to work like that.
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Help me understand - (Score:3)
When I look at the picture in the article, there is a truck with the solar panel and a trailer with the desalination system. So, it is portable, can be driven where needed. They can process 5000 liters per day, approx 1320 gallons. Water usage statistics in the US can be found online for water districts and municipalities - rates vary some, but 300 gallons per day per household seems to be a fair average. Relatively dry places might use much less, so I am estimating maybe as low as 300-400 liters per day per household, let's say 333. Then 5000 / 333 = 15, so one daily batch of processed clean water can serve a water-frugal household for 15 days. A service could drive a truck around to the customers, spend one day on site to make enough water for one house for 2 weeks, then drive to the next customer, then repeat the circuit every 2 weeks, 14 customers net for each rig. Of course, if used in small villages, the business or process model might be different, one truck making enough water for 15 households, repeat every day. You can scale up the technology, make bigger trucks, put more trucks in service or on site, etc.
But here is what I don't get. The project engineers seemed to be obsessively, compulsively, morbidly obsessed with minimizing or eliminating battery storage from the process. Why? If their main goal was to prove that they can match load, their machine, to available power, the sun, and thereby keep the equipment running as efficiently as possible using their ideas about control based on frequent sampling - okay, they proved it. But why not use batteries?
It seems that countless electrical systems are now incorporating battery storage into their machines, even the power utilities themselves. As battery technology and energy storage have developed in the past 10-20 years, it seems like batteries will be a crucial component of nearly all power systems in the future. Why waste capturable energy when you can store it, then use it off hours when the sun isn't shining?
So, why do these guys want to avoid batteries like the plague? Seems like battery would be a useful component to keep the desalination running "off hours", increasing throughput and net yield, perhaps doubling capacity for each truck.
Anyone here on Slashdot have experience with these things and has some insight?
Solar powered desalination system? (Score:2)
I thought we already had one of those, and it could provide enough drinking water for the whole country.
Its called the Gulf of Mexico.
Solar still (Score:2)