A Northwestern University-led team of researchers has developed a new fuel cell that harvests energy from microbes living in dirt. About the size of a standard paperback book, the completely soil-powered technology could fuel underground sensors used in precision agriculture and green infrastruct

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.

  • cmnybo@discuss.tchncs.deEnglish
    572·
    9 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@sh.itjust.worksEnglish
      37·
      9 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@lemmy.worldEnglish
        13·
        9 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@kbin.social
        4·
        9 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@kbin.social
      12·
      9 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.

    • Magrath@lemmy.caEnglish
      74·
      9 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@lemmy.worldEnglish
        10·
        9 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@lemmy.worldEnglish
    25·
    9 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.”