MIT Unveils Portable, Solar-Powered Water Desalination System 117
An anonymous reader writes "A team from the Massachusetts Institute of Technology's Field and Space Robotic Laboratory has designed a new solar-powered water desalination system to provide drinking water to disaster zones and disadvantaged parts of the planet. Desalination systems often require a lot of energy and a large infrastructure to support them, but MIT's compact system is able to cope due to its ingenious design. The system's photovoltaic panel is able to generate power for the pump, which in turn pushes undrinkable seawater through a permeable membrane. MIT's prototype can reportedly produce 80 gallons of drinking water per day, depending on weather conditions."
Damn you, science jornalism. (Score:5, Insightful)
Pump-fed nanofilters are sort of an old idea at this point. The summary leaves off some critical points like how much it costs and how long the filter lasts.
According to the article, it costs $8000, which is a lot for some things but probably accessible for others. Let's just say it's not going to solve the world's water problem overnight, but it might be handy for relief efforts.
Surfing through to the parent MITnews article [mit.edu], we get a bit more information, but it's still lacking anything about how long the system can operate or what its maintenance costs and requirements are. Does it last a week then you're out most of another $8000? Does it require a lot of technical expertise to maintain? It doesn't say...
Not revolutionary (Score:2, Insightful)
While this design is a step up, and it certainly must have been a great engineering challenge to build and integrate, there is no groundbreaking technology that goes into this. It's a simple reverse osmosis plant, based on technology that's already being used at commercial scale. The summary is also misleading - this system also requires a lot of energy, it just has a power source with it. In fact, it's almost certainly less efficient than a conventional RO system, both in terms of energy used and embedded energy in the solar panel and equipment used up over the equipment's lifetime. Bravo for making it modular, but what went into it is pretty clearly old news.
Optional attachments... (Score:3, Insightful)
And for about 8 more dollars, they could attach a big funnel and bucket for those days when it rains and the solar part doesn't work so well.
Boats (Score:5, Insightful)
Question (Score:5, Insightful)
Re:Cost (Score:3, Insightful)
MIT = big news (Score:2, Insightful)
The headline idea has a lots of flaws. For $8000 you can dig a well and install a pump that can supply the water for 250 people. Not only that, you'd have enough money left over to either cover any repair costs for a long time or to put towards another pump. A lot of African villages already have problems with more complex electric pumps, not being able to afford to pay for maintenance so the pumps sit inactive. This desalination plant will have the same issue but with the added expense of filters.
How often do you need to replace the filter? 300litres of salt water means 10kg of salt that presumably is stopped by the filter so it would quickly clog up and have to be rinsed several times a day. More problematic are the 450g of other impurities the filter would pick up that may not wash out. I can't see a filter lasting long.
Innovation????? (Score:4, Insightful)
Sorry, but this just looks like a bog-standard boat desalinization system hooked up to some solar cells. I fail to see what is so earth-shattering about it.
Re:80 US gallons (Score:3, Insightful)
for large scale disasters it makes a LOT more sense to drop 2 of those and two fuel/generator sets and supply 10x more people with fresh water since every cargo flight counts.
That may depend on how close together those people are.
If people are spread across a large area in many small villages, then perhaps many small setups is a more suitable option.