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

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

#21

Post by Scarblac »

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?

H2O turns into a sort of gravity-propelled fluid form known as "rain", and then its greenhouse effect in the atmosphere ends quickly.

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

#22

Post by labster »

Xylakant wrote: post #13
zabzonk wrote: post #10

Earlier quoted context omitted.

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...

But ultimately on Earth, even in the dry polar latitudes, there’s certainly enough water to absorb everything in the H2O spectrum lines. The atmosphere is lousy with water, generally 1-3%, meaning it is usually the third most abundant gas.

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

#23

Post by cartoonworld »

lifeisstillgood wrote: post #16

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... )

Wood gas was really common and used to power all kinds of lighting before electrification. FEMA even created and distributed plans[0] for a Gasifier in the late 80's. You can find the PDF all over the internet, I think its a pretty cool looking project.

Youtube is full of weird wood gas car projects such as this pickup truck: https://www.youtube.com/watch?v=9AFw3Agg7SM

I don't see how these could be street legal in general, but pretty fun.

[0] https://survivalring.org/pdf/fema_wood_gas_generator.pdf

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

#24

Post by labster »

konschubert wrote: post #12
zabzonk wrote: post #10

Earlier quoted context omitted.

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.

Outside the microscale, you’re essentially right. But water emissions have outsized effects as contrails from jets, by causing ice cloud condensation where it wouldn’t naturally occur. The heating is quite significant, as we discovered in studies of the September 11 air travel shutdown.

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

#27

Post by Broken_Hippo »

helsinkiandrew wrote: post #17

> 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?

Maybe, maybe not. It isn't like most folks can live off of a garden plot of a normal house, if you even have a garden plot.

I cannot cycle 20km fairly leisurely in an hour: I live in a mountainous area, but lived most of my life on flat ground and going uphill is freaking difficult, even if I'm going at a leisurely speed - and sometimes, downhill is brakes all the way down.

And I don't know how much this person drives. Most places I go to are within walking distance, and I'm pretty sure 8 hours of ditches would be less work than an entire summer of gardening (where I'd have to rent a plot, since I'm an apartment dweller). The majority of my foodstuffs are going to still be driven in, too.

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

#28

Post by Xylakant »

labster wrote: post #22
Xylakant wrote: post #13

Earlier quoted context omitted.

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...

But ultimately on Earth, even in the dry polar latitudes, there’s certainly enough water to absorb everything in the H2O spectrum lines. The atmosphere is lousy with water, generally 1-3%, meaning it is usually the third most abundant gas.

Sure, but the question here is “does the water vapor from burning Methane add to the vapor in the atmosphere?”, which is different from “is water vapor the most important contributor to the greenhouse effect?”

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

#29

Post by hannob »

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...

You can probably do that, but don't delude yourself that you're doing anything for the environment.

Methane itself is a very potent greenhouse gas. Everything you do with methane is only environmentally friendly if you have a very low leakage rate. Whatever homegrown DIY biogas facility you're creating very likely does not do that.

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

#30

Post by Hendrikto »

Broken_Hippo wrote: post #27
helsinkiandrew wrote: post #17

> 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?

Maybe, maybe not. It isn't like most folks can live off of a garden plot of a normal house, if you even have a garden plot. I cannot cycle 20km fairly leisurely in an hour: I live in a mountainous area, but lived most of my life on flat ground and going uphill is freaking difficult, even if I'm going at a leisurely speed - and sometimes, downhill is brakes all the way down. And I don't know how much this person drive…

> I cannot cycle 20km fairly leisurely in an hour: I live in a mountainous area

Not a good counter argument. In this case, the moped will also use more fuel.

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