*Bacteria and graphene nanoribbons 3D printed on a mushroom generates 65 nanoAmps.<p>I'm going to go out on a limb here and say that the energy it produces over the lifespan of the mushroom is several orders of magnitude less than goes into manufacturing the 'bionic' bits.<p>I can't find how long A. bisporus lives after it caps but I'm guessing weeks at best. I'm not paying for the paper so I have no idea if they mention voltage and I have no idea what voltage might be capable of being produced by I'm guessing it's going to be considerably less than a boiled potato (5ish volts)... sooo...<p>Almost certainly less than 3.25e-7 watts, so you're talking tens of thousands of weeks to even get a watt hour.<p>Just the two of us visiting the link likely used more electricity than one of those would produce in a century, if not a millennium or more.