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How would you power a weed-whacker via non-traditional methods? AFAIK there are three main technologies in use today: gas, battery, and plug-in electric. Assu

How would you power a weed-whacker via non-traditional methods? AFAIK there are three main technologies in use today: gas, battery, and plug-in electric. Assuming that gas is on the way out, chemical batteries have contamination/recycling issues, and plug-in electric isn't appropriate for all use cases (definitely less convenient). I can't think of anything other than those technologies which comes remotely close to power a small engine for ~30 minutes at a time, once a week. Will we ever get to "nuclear-powered" weed-whackers? Wouldn't it be Great(tm) if there were the equivalent of AA/AAA rechargeable batteries but for larger devices? Maybe the 6-cell laptop format is the winner (but look at the variation in that use-case)...

kortex 7y ago
I have an electric weed wacker, and for my purposes it works great. But even for more industrious weed wacking demands, I don't think small gasoline engines are contributing that much to global carbon. Pollution and smog, otoh, two strokes are notorious for polluting.
Mirioron 7y ago
>Will we ever get to "nuclear-powered" weed-whackers? I wanted to say "probably not", but I looked some stuff up and now I'm unsure. Essentially all small scale "nuclear power" uses a Radioisotope Thermal Generator. You essentially have a radioactive rock that generates heat and the heat difference is used to generate electricity through the Seebeck effect. The fuel that's typically used for this is Plutonium-238, because it almost exclusively decays as alpha particles (helium-4 nuclei), it has a half life of 87 years while being the most (of the long half life ones) energy dense at around 0.57 W/g. This is what's used in space flight missions and has actually been used to power pacemakers in the past with essentially no ill effect on the patient. Pu-238 is still too heavy for the amount of power it generates for a weed-whacker. What changed my mind though is that apparently Polonium-210 also almost exclusively decays as alpha particles, but it has an incredible 140 W/g power density. The problem is that it has a half life that's only about a third of the year. It still could technically be used for a weed whacker though. From a practical standpoint though, small scale "nuclear power", through RTGs, is way too inefficient for it to be used by regular people. Even if you eliminated all the risk of contamination, it would still only make sense for things that need to be running 24/7 that you couldn't swap out the battery on. Fission and fusion, so far, require a far larger plant to generate power.
fulafel 7y ago
You could just burn the whacked weeds as fuel and power a microturbine, micro steam engine or other something.

kortex 7y ago

I have an electric weed wacker, and for my purposes it works great. But even for more industrious weed wacking demands, I don't think small gasoline engines are contributing that much to global carbon. Pollution and smog, otoh, two strokes are notorious for polluting.

Mirioron 7y ago

>Will we ever get to "nuclear-powered" weed-whackers? I wanted to say "probably not", but I looked some stuff up and now I'm unsure. Essentially all small scale "nuclear power" uses a Radioisotope Thermal Generator. You essentially have a radioactive rock that generates heat and the heat difference is used to generate electricity through the Seebeck effect. The fuel that's typically used for this is Plutonium-238, because it almost exclusively decays as alpha particles (helium-4 nuclei), it has a half life of 87 years while being the most (of the long half life ones) energy dense at around 0.57 W/g. This is what's used in space flight missions and has actually been used to power pacemakers in the past with essentially no ill effect on the patient. Pu-238 is still too heavy for the amount of power it generates for a weed-whacker. What changed my mind though is that apparently Polonium-210 also almost exclusively decays as alpha particles, but it has an incredible 140 W/g power density. The problem is that it has a half life that's only about a third of the year. It still could technically be used for a weed whacker though. From a practical standpoint though, small scale "nuclear power", through RTGs, is way too inefficient for it to be used by regular people. Even if you eliminated all the risk of contamination, it would still only make sense for things that need to be running 24/7 that you couldn't swap out the battery on. Fission and fusion, so far, require a far larger plant to generate power.

fulafel 7y ago

You could just burn the whacked weeds as fuel and power a microturbine, micro steam engine or other something.