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by helsinkiandrew 1806 days ago
> 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?

5 comments

I know HN comments have a knack for trying to min/max and optimize something posted, but honestly that's not the point here. He's proving that it's possible to harvest methane from ponds, enough to power a moped.

OF COURSE there's more efficient ways to get around, this isn't an attack on anyone's intellect or common sense and there's no need to react to getting nerdsniped by going "well ackchyually" and reinventing combustion engines and fuel from first principles.

It's fine to just go "that's cool" and move on with your life. The guy that made this knows it's not the most efficient use of his time.

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 prefix.

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.

The downside would be that probably only a small fraction of people would read those. Which might be worth saving the annoyance of people having this reaction (and the random people convinced they are reading about anything but an art project).
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.
whoa, even dang has only 25k. I'm not longer going to listen to him when he threatens bans.
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 usefulness.

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.
"nerdsniped" is my new favorite word - thank you for this post haha
One could easily walk 20km in 8 hours.
At an average pace you could walk 20km in half that time
When I was growing up, we walked that to school each day, uphill, in a snowstorm!
Oh, you lucky bastards! I could dream of walking to school. We were taking lessons in the snowstorm.
Luxury!
5km per hour is easily doable, I believe. A group of us in high school once did that and covered about 105kms in 3 days. We walked just about 7 hours every day for those 3 days.
My great-great-grandfather in the late 1800s got a land grant. I'm trying to work out how he got the farm started, because apparently he used to catch the train from his labourer job in the bit city, then walk 70km to his land.
And with the right preparation you could collect methane too.
Underrated comment.
more like 3-4 hours at max, this seems terribly inefficient
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.

> 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.

Sure, it isn't the best, but I know lots of other folks cannot either, and reasons vary. The point really is that cycling 20km isn't realistic for a wide swath of population.

And sure, it might use more fuel... when you go uphill. Downhill, you might not even need the power.

You can also leisurely coast downhill on a bicycle at a much higher speed than 20 km/h.
> Downhill, you might not even need the power.

Same as with a bike.

> It isn't like most folks can live off of a garden plot of a normal house

The trick is to grow for value and flavour, not staples/calories. Probably still a terrible $ yield.

Nonetheless, I think the 1 abused apple tree is going give me months of apples.

Fair enough, but my main point was that cycling or walking 20km probably consumes less energy than the “hard work” of harvesting methane for 8 hours.
Possibly, but this isn't really the tradeoff. It is using energy when you have time to reap the benefits when you actually need the quick travel. 20km is going to take hours to walk in one trip.
Now I'm imagining an alternate history/sci-fi planet where a neolithic society manages to effectively harness swamp gas (and eventually develop anaerobic digesters to produce it) as an energy source, instead of relying on timber/biomass.
I imagine he could improve it a lot. All that wood is making it pretty heavy. And it's a late 70s-era 4-stroke 50cc scooter. Something newer is probably more efficient.
Is it just me or did anyone else see an opportunity for automating this? He seemed to be working up and down. A fully mechanical / hydraulic actuator could do this.
He just has to go to a landfill and connect that balloon to a methane release port.
I would imagine a good use of a windmill could be use to pump and accumulate.
He has footage of a Wind powered Gasmaaier on his site.

Although it's possibly CGI -

https://uitsloot.nl/infrastructuur/

For moving a single human being 20km, you could easily use a solar panel and an electric bike.
I was trying to stay within the non-electric aspect of this. Solar isn’t exactly something you can make yourself. Methane however is vaguely doable given a bit of effort and skilling up.

Edit: when I write "make" I don't mean "install".

You can very easily do a solar installation yourself. But even more interestingly, even biomass-derived methane is more efficiently burned in a CCGT plant (>60% efficiency) to generate electricity for charging an e-bike than in an ICE engine on a moped (~20-25%?). And even better, a smart charger can charge an electric vehicle from an electric mix (NG/wind/solar/nuclear) optimally, so you can run from whatever is best at that moment.
From a global warming perspective, harvesting free methane and burning it is probably a net benefit given how much stronger methane is of a warming agent than the CO2 it burns into.
> Solar isn’t exactly something you can make

I think “make” is the important part here, not buy and install.