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Inventor harvests methane gas from ditches and ponds to power his moped

notechmagazine.com

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Re: Inventor harvests methane gas from ditches and ponds to power his moped

#11

Post by usrusr »

NotSwift wrote: post #2

Please note that this is an art project and not a serious invention.

Agreed, the term "inventor" in the headline makes it seem unnecessarily naive.

But even if it's art, I suspect that some objective benchmark comparison fits very well: assuming that you had serfs to do the dirty work for you, at eight man-hours for 20 km this would be clearly more efficient than having them carry you around in a sedan. And only slightly less efficient than a rickshaw. Great way to put our fossil every consumption into perspective!

Re: Inventor harvests methane gas from ditches and ponds to power his moped

#12

Post by konschubert »

zabzonk wrote: post #10
Xylakant wrote: post #8

Earlier quoted context omitted.

True, but methane has a much stronger greenhouse effects than the resulting CO2 and water vapor. So that's still net-positive.

Actually, H2O is the most potent common greenhouse gas, then methane, and then CO2. If you burn methane (CH4) you end up with 2 molecules of H20 and one of CO2. Which to me would seem to be worse than one molecule of CH4 - but I might be wrong. Perhaps someone more knowledgeable could comment?

The amount of water in the atmosphere is probably independent of how much water vapour we emit.

Re: Inventor harvests methane gas from ditches and ponds to power his moped

#13

Post by Xylakant »

zabzonk wrote: post #10
Xylakant wrote: post #8

Earlier quoted context omitted.

True, but methane has a much stronger greenhouse effects than the resulting CO2 and water vapor. So that's still net-positive.

Actually, H2O is the most potent common greenhouse gas, then methane, and then CO2. If you burn methane (CH4) you end up with 2 molecules of H20 and one of CO2. Which to me would seem to be worse than one molecule of CH4 - but I might be wrong. Perhaps someone more knowledgeable could comment?

Water is the only gas of the three that condenses in atmospheric conditions. The total amount of water vapor that air (or the atmosphere) can hold depends on temperature more than anything else, excess water remains in the atmosphere for days only. This seems like good overview.

https://www.newscientist.com/article/dn11652-climate-myths-c...

Re: Inventor harvests methane gas from ditches and ponds to power his moped

#14

Post by londons_explore »

nyanpasu64 wrote: post #7

What is the best way to deal with a pond lined with soil taken from dry ground, which emits methane bubbles nonstop when underwater? I'm concerned it's hurting life in the water.

It'll stop bubbling in a few months.

Add a fountain to aerate the water to speed it up.

Re: Inventor harvests methane gas from ditches and ponds to power his moped

#15

Post by GrumpyNl »

trompetenaccoun wrote: post #4
NotSwift wrote: post #2

Please note that this is an art project and not a serious invention.

Well... if it gets a few people to learn more about this topic then that's serious enough for me. Many have very strong opinions about energy and fossil fuels, but few really understand what they're talking about. For example they don't understand that natural gas is actually a very potent greenhouse gas and he's doing the world a favor by burning it. On a larger scale, we could certainly do more to stop methane from…

Next step, tank it directly from the cow.

Re: Inventor harvests methane gas from ditches and ponds to power his moped

#16

Post by lifeisstillgood »

Wood gas vehicles were, well not uncommon:

https://www.lowtechmagazine.com/2010/01/wood-gas-cars.html

Due to the need for oil (major cause of second world war anyway) Nazi Germany produce 1/2 million cars run on wood gas.

(Had to google this but just remembered the image from "The Knowledge" well worth a read: https://www.amazon.co.uk/Knowledge-Rebuild-World-After-Apoca...)

Re: Inventor harvests methane gas from ditches and ponds to power his moped

#17

Post by helsinkiandrew »

> Eight hours of hoeing in a ditch supplies him with enough fuel to ride his vehicle for 20 km

Hmm, this is an art project but you can cycle 20km fairly leisurely in an hour.

8 hours of toiling in the ditches probably might be better used growing vegetables so your food isn’t being driven in?

Re: Inventor harvests methane gas from ditches and ponds to power his moped

#18

Post by shash »

fy20 wrote: post #3

If you want to do this seriously, you could probably do quite well by creating biogas from kitchen scraps: https://www.motherearthnews.com/renewable-energy/other-renew...

Growing up, my grandparents' house had a biogas plant, powered by cowdung (they had anywhere between 6 and 8 cows and bulls at the time). Looked something like this: https://www.peda.gov.in/nnbomp

Most of the cooking and some of the lighting for the house was done using this thing. Most of the bigger houses in the village had one.

Re: Inventor harvests methane gas from ditches and ponds to power his moped

#20

Post by labster »

zabzonk wrote: post #10
Xylakant wrote: post #8

Earlier quoted context omitted.

True, but methane has a much stronger greenhouse effects than the resulting CO2 and water vapor. So that's still net-positive.

Actually, H2O is the most potent common greenhouse gas, then methane, and then CO2. If you burn methane (CH4) you end up with 2 molecules of H20 and one of CO2. Which to me would seem to be worse than one molecule of CH4 - but I might be wrong. Perhaps someone more knowledgeable could comment?

Water is the most powerful greenhouse gas because it’s so abundant. Because it is so abundant though, the absorption lines are pretty much maxed. Besides the available quantum states (1 and 2 atom molecules cannot be GHGs) which make CFCs more powerful, the main impact on GHG strength is relative abundance. Methane is rare, so every atom is important, CO2 is uncommon, and H2O is common. I guess that makes CFCs a foil, lol.
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