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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

#141

Post by yunohn »

jhgb wrote: post #140
yunohn wrote: post #138

Earlier quoted context omitted.

The perspective I get from the article is of decentralized self sufficiency. Being able to harvest methane in their locality, and use that as fuel is quite appealing versus purchasing and installing solar panels or relying on power lines. I’m not saying your math doesn’t check out; rather, the author is going for a different set pro/cons than just pure “efficiency”.

I bet you'd still be able to do this in a local municipal biogas plant more efficiently. It would also scale better should you wish to run more than several mopeds like this.

Again, that’s centralized. Less central than your previous example, but still requires a dependency on their municipal plant and power lines. Not sure why this is a confusing concept.

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

#142

Post by fennecfoxen »

ortusdux wrote: post #123
dv_dt wrote: post #122

Earlier quoted context omitted.

My local landfill now taps that methane and powers generators with it.

That's what the landfill transitioned to. I believe it now powers all the buildings onsite.

When I was still at school, I had occasion to tour the local sewage treatment facility as a field trip. They had equipment to power all the buildings on site with captured methane, but did not use it, because it was cheaper to just buy electricity from the grid supplier than it was to operate and maintain the generator with free methane fuel. (The methane was still burned.)

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

#143

Post by rualca »

jasonhansel wrote: post #112
rualca wrote: post #71

Earlier quoted context omitted.

Methane is estimated to be an order of magnitude or two more powerful than CO2. https://unece.org/challenge

That's if you release the methane, not if you burn it; assuming you burn all of it, the resulting CO2 is the bigger concern.

> That's if you release the methane, not if you burn

You're talking about a guy who is trapping methane that's already being released and burning it.

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

#144

Post by ineedasername »

schoen wrote: post #129
hn_throwaway_99 wrote: post #84

Earlier quoted context omitted.

I agree with you, but I think part of the reason people have the reaction they do is that they start with the headline, which teases people into thinking this is something that is actually semi-viable, and then when they go in to read the article they find it is basically an art project, so there is this dissonance between expectations and reality. I almost feel like we need a "Show HN an Art Project:"-like headline…

Compounded here by the headline starting with "Inventor". Typically "inventor does X" reads as a proof of concept of something other people might someday want to do, too.

I suppose someone might figure a way to economically scale the methane captured here.

Of course the method this person used, agitating the bottom of the pond, could have an adverse impact of the ecosystem of the pond itself. Do they rely on trace quantities of methane in some way? Will the muddy & cloudy disturbed water make survival harder, maybe killing the biomass that was generating the methane? Who knows. Well, someone might know, but I guess my point is that agitating metastable systems can have outcomes that are hard to predict.

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

#145

Post by ineedasername »

NegativeLatency wrote: post #96
geoduck14 wrote: post #91

Earlier quoted context omitted.

Serious question, why would you use a throwaway account for a comment like this?

Maybe the name is just a joke? user: hn_throwaway_99 created: February 20, 2017 karma: 28836

Really any account with less than 100k karma is practically a throwaway account.

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

#146

Post by ineedasername »

AtlasBarfed wrote: post #120
throwaway2a02 wrote: post #118

Earlier quoted context omitted.

People have built solar bikes, as in regular ebikes with 2-300w panels attached that power the motor. That's more impressive if you ask me. Other than that, lots of people (myself included) have run old, indirect injection diesels on used veg oil. That was years ago when it was financially very advantageous. If you ask me, these are more impressive/interesting technical feats, but with real world applicability and us…

That's what popped into my mind: the old waste fryer diesel fuel. A nice "gee whiz" science reporting that the MSM eats up, but not scalable in any way for any significant application.

Also not scalable because "waste" oil is, by & large, not usually wasted. Restaurants are often paid by collectors who repurpose it for a variety of applications, including biofuel. So the idea that massive quantities of fryer oil get wasted when it could be used is a myth.

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

#147

Post by simonh »

fennecfoxen wrote: post #142
ortusdux wrote: post #123

Earlier quoted context omitted.

That's what the landfill transitioned to. I believe it now powers all the buildings onsite.

When I was still at school, I had occasion to tour the local sewage treatment facility as a field trip. They had equipment to power all the buildings on site with captured methane, but did not use it, because it was cheaper to just buy electricity from the grid supplier than it was to operate and maintain the generator with free methane fuel. (The methane was still burned.)

The awful thing is that the greenhouse gas emissions involved in manufacturing the generator and maintaining it might have been significantly greater than the emissions due to the grid electricity. Not all these decisions are simple.

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

#148

Post by Robadob »

oh_sigh wrote: post #110
danuker wrote: post #106

Earlier quoted context omitted.

A thousand-mile journey begins with the first step. Even a little helps.

With the obesity epidemic it is probably better to tell people they can just compost their food if there is too much and they can't eat it. And then cook a little less next time. I keep 100% of foodstuff out of my trash, and an added benefit is that you never get stinky trash that needs to be taken out. I take my trash out every 2 weeks and it never smells at all.

My parents regularly throw out spare food (bread, meat, fruit) onto their lawn, local wildlife (birds, foxes, hedgehogs) always take it all within 24h.

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

#149

Post by NotSwift »

Cthulhu_ wrote: post #79
GrumpyNl wrote: post #15

Earlier quoted context omitted.

Next step, tank it directly from the cow.

I googled quickly and the summary says "A single cow on average produces between 70 and 120 kg of methane per year", so that would actually probably be feasible. Getting it would the challenge though. That said, if I were to over-engineer this, they could make barns with a closed air system that filters out any methane produced.

This might not be as far fetched as you assume. Large farms in the Netherlands are already required to have some filtering systems for reducing the output of Nitrogen-based compounds.

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

#150

Post by coding123 »

ineedasername wrote: post #145
NegativeLatency wrote: post #96

Earlier quoted context omitted.

Maybe the name is just a joke? user: hn_throwaway_99 created: February 20, 2017 karma: 28836

Really any account with less than 100k karma is practically a throwaway account.

whoa, even dang has only 25k. I'm not longer going to listen to him when he threatens bans.
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