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Engineers at MIT and in China develop desalination system which could produce freshwater that is cheaper than tap water (news.mit.edu)
submitted 2 years ago by to c/technology@lemmy.ml
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It looks like the paper is paywalled and not yet on scihub but i did find 38 pages of supplemental information with more details than the article.

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[–] 36 points 2 years ago (2 children)

For example, tap water in my city costs ~$0.04 per gallon, at 5 gallons per hour, 24 hours per day, for 5 years is $1,752. So saying they can make it for less than the cost of tap water doesn’t mean it’s affordable.

Or maybe the product just isn't for you, but for people who pay significantly more for, or possibly don't have access to drinkable tap water at all.

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  • [–] 8 points 2 years ago*

    But furthers the point I'm making. If your water costs more than mine then the potential price of this machine is even higher and the base price is already expensive as is. If this was truly a cheap and affordable alternative for people's in need then it likely would have made that price point a major point of the article.

    Just because it's cheaper than an alternative doesn't make it affordable.

    EDIT: Also the article says

    "the team estimates that the overall cost of running the system would be cheaper than what it costs to produce tap water in the United States."

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  • [+] -7 points 2 years ago (1 child)

    It's a solar distillation machine. The compact size is useful but there are dozens of ways to do this for almost free as long as you were within reach of an ocean. You can dig a hole in the sand put a piece of clear plastic over and a catch basin in the center and do the same thing. It's interesting but not really earth-shattering.

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  • [–] 13 points 2 years ago (1 child)

    You can't "just do this" because you live by the ocean. You're over simplifying it because you aren't impressed.

    For coastal people of impoverished or war-ridden locations with tainted or unavailable groundwater supplies, this is amazing if it becomes reality.

    Your normal isn't most people's reality. Clean drinking water is not ubiquitous.

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  • [+] -11 points 2 years ago (1 child)

    Are you telling me you can't make a solar still out of a sheet of plastic a bowl and a hole in the sand at the beach? Because if you don't think that works we have no further need to communicate.

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  • [–] 11 points 2 years ago (1 child)

    Hope much drinkable water are you generating with your sand hole and plastic? This thing can allegedly generate liters per hour. Enough to sustain a decent sized group of people.

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  • [–] -2 points 2 years ago* (last edited 2 years ago)

    The numbers provided are qualified with "if they can scale it" up. So they don't even actually know that they'll get that rate.

    Edit: MythBusters did it They pulled a about a half cup an hour out of a 6-ft wide hole. Best case if you are engineering this you could put a frenzel lens in front of a pan of salt water your energy conversion would be like 99%. For using sunpower, The amount of water you're going to extract is directly related to how much energy you can collect.

    I'll believe their numbers when they actually bother to scale it.

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