Northwestern University researchers have introduced a soil-microbe-powered fuel cell, significantly outperforming similar technologies and providing a sustainable solution for powering low-energy devices.

  • @[email protected]
    link
    fedilink
    English
    5510 months ago

    How much power does it produce? It must be pretty bad since they don’t mention it anywhere in the article.

    • Tar_Alcaran
      link
      fedilink
      English
      37
      edit-2
      10 months ago

      They claim “68 times more than required to operate the sensors”, then mention a sensor to measure soil moisture.

      A basic soil moisture sensor, like say, the ones I have stacked on a shelf here, will work on 2 AA batteries. It runs on 2V at 10mA. So that’s 20 milliWatts, and in willing to be a fair bit of that goes into the electronics that make a red, green or orange led light up at certain moisture levels, and the bit that beeps when below a certain level.

      Still, this sets something of an upper limit at 1.3W, or maybe 680 mA? Those seem rather high, so I’m betting their moisture sensor is a bit more delicate than my model. It depends on the size and number of cells though.

      • @muntedcrocodile
        link
        English
        1410 months ago

        Im pretty sure most soil moisture measurment devices just measure the capacitance to measure dielectric permittivity. U can design such a setup to use any arbitrary amount of power depending how close the electrodes are rogether etc etc.

      • Willie
        link
        fedilink
        5
        edit-2
        10 months ago

        Yeah, I am imagining the soil moisture things from the garden store, with the little needle gauge thing, that takes so little power that there’s no battery slot. I feel like the amount of power this thing makes is extremely low.

    • WHYAREWEALLCAPS
      link
      fedilink
      1210 months ago

      The linked article has a table that gives 1.74 uW/cm^2. However glancing over the rest of the paper there’s a ton of variability of output.

      • @Buffalox
        link
        English
        210 months ago

        Damn I hoped it would go to eleven, I need that little bit extra.

      • @RealFknNito
        link
        English
        510 months ago

        Depends on how many fuel cells you get and are able to shovel dirt into

  • @Son_of_dad
    link
    English
    3310 months ago

    Love these pie in the sky articles that get debunked immediately in the comments

    • @[email protected]
      link
      fedilink
      English
      410 months ago

      Who debunked this? I don’t any comments debunking it.

      Also if you read the article it has limited applications so it’s not some pie in the sky you think it.

      • @linearchaos
        link
        English
        1010 months ago

        I kind of get op’s point. It’s not straight up debunked, but it’s so few microwatts that they can power the sensor but they can’t store log data.

        It requires a close proximity powered base station nearby to fire a signal out to get reflected back somehow.

        I’m having a hard time picturing any viable setup outside of a laboratory experiment. If you’ve got a powered base station within a few inches of it why not just power it with that?

  • @TheOneWithTheHair
    link
    English
    2410 months ago

    " As long as there is organic carbon in the soil for the microbes to break down, the fuel cell can potentially last forever.”

    It’s also a stationary battery

    “Although the entire device is buried, the vertical design ensures that the top end is flush with the ground’s surface.”

      • @[email protected]
        link
        fedilink
        English
        1
        edit-2
        10 months ago

        I’d say a battery is at least something that should be “chargeable”, either one time or rechargeable. I dont think you can use solar cells to store energy back into the sun.

        Not saying that my definition does work for the dirt fuel cell, talked about in the article, though.

  • @pandacoder
    link
    English
    510 months ago

    So if the tip is sticking out for airflow, how does it handle a flash flood?