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Inventor harvests methane gas from ditches and ponds to power his moped (notechmagazine.com)
261 points by rudenoise on July 13, 2021 | hide | past | favorite | 174 comments

My local landfill growing up had an decent sized methane burn-off flame running 24/7. I would put it on par with a wide open hot air balloon burner. My dad told me it was there to commemorate all the unknown meals that people threw in the trash, so I should always finish my dinner out of respect.

As a kid I am sure that made more sense than “to save the planet a little”.

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.

Not much wilflife about it then.

I seperate my compostables as well. I don't even use a trash bag in my bin anymore. My trash bin fill up so slowly that I go months without taking it to the street.

My uneaten food went into the fridge for my next meal as a kid.

Sorry you had abusive parents

Eating leftovers is perfectly fine, and a hell of a lot less wasteful than dumping it in the compost.

IMO leftovers taste better than the original meal.

How do you deal with meat leftovers? You can compost plant remains but meat becomes another issue.

Find a neighbor with a carnivorous pet.

Alternatively, eat less (or no) meat; it's good for the environment: https://ourworldindata.org/food-choice-vs-eating-local

OTOH the 80/20 rule for optimization says to not waste effort on tiny inefficiencies.

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.)

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.

Better might be to capture the methane and use it to supplement residential natural gas. Here in BC you have the option to convert any percentage of your residential NG usage to 'biogas' AKA methane. (You just need to pay the higher cost for the gas.) Technically it doesn't change what comes out of your pipes, but they purchase and inject into the system an aggregate amount of biogas equal to what's purchased by customers. So you're directly offsetting burning of NG by instead using the methane that would, best case, be burnt anyway. Of course there is some waste in storage and transportation and such still, but seems like a win. At least, until all the 'free' landfill methane gets used up, and people start creating methane farms.

It's hardly clear that building, installing, and maintaining all the equipment necessary to do that would require less energy than the methane they are wasting.

To a rough approximation, the fact that no one found it financially worthwhile already tells you that you need a ton of resources to make it happen.

Seems like in the US there are 500+ landfill gas projects operational with about another 500 possible sites - so not exactly no one.


Remember to factor in that capturing the methane and burning it is in itself a substantial good in the greenhouse gas equation. Methane is an extremely potent greenhouse gas if allowed to release in its raw form, far more so than CO2 and water vapor - the products of its combustion.


> 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?

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.

Maybe HN stores karma as a 32-bit integer and dang had a buffer overflow and is simply wrapping back around to 25k now.

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.


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 -


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.

And we're already harvesting biomass to turn it into biogas. You can do it on a larger scale and it's still more efficient than running a moped motor.

> Solar isn’t exactly something you can make

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

Would you insist that you should be able to "make" the moped? Nobody will be as self-sufficient as the early Neolithic people ever again. For me, "making" things by building them from mass-manufactured components such as solar panels is perfectly fine. People don't shy from installing solar panels just because they can't manufacture them themselves from sand anymore then they shy from buying electric motors or CPUs.

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.

The concept is not at all confusing, it's just useless. For load balancing, efficiency, and reliability reasons, a microgrid is more desirable than isolated households in pretty much all circumstances.

I'm not sure disrupting the ecosystem at the bottom of the pond is an ecologically sound move. Biodiversity is important!

Obviously I understand this is a proof of concept and not the solution to fossil fuels.

Agreed this was one of the first things I thought outside the balance of energy required for the whole thing doesn't make much sense.

What are we supposed to take away from this project other than its kind of neat and that methane occurs natural in the environment? We are not about to mining ponds for methane - we already have plenty of it accessible at LFG, waste water treatment facilities, methane from O&G operations.

it probably speeds things up rather than killing them, and you know on the scale of BP pouring millions of oil into the ocean, I reckon what this guy is doing is absoloutley fine and the environmental damage is well within range of what the local environment can cope with and recover from within a reasonably small time frame.

It's "probably" ok? Based on what?

Methane is a much more potent green house gas than CO2.

>and you know on the scale of BP pouring millions of oil into the ocean, I reckon what this guy is doing is absoloutley fine and the environmental damage is well within range of what the local environment can cope with and recover from within a reasonably small time frame.

But BP serves millions of customers. If you normalize by that (ie. pollution divided by customers), my guess is that digging up ponds is more environmentally damaging than buying gas at the gas station.

if you destroy the support systems that all organic life depends on, then you aren't serving the customers all that well...

I think you're misreading my comment. It's not to say that it's okay for BP to spill oil, it's that all things considered, the environmental impact of a tank of gas (extracted using current methods) is much less than what this guy is doing. Imagine the alternative: rather than every american filling up at the gas pump, they're dredging up ponds/ditches for methane. How much environmental impact would that cause? Is that better than the occasional oil spill we get?

Lots of funny wordplay there: uitstoot = emissions but uitsloot translates as 'from the ditch'. grasmaaier = lawnmower ('grass mower'), but 'gasmaaier' = grass mower running on gas.

There aren't a lot of places that use anaerobic digesters (fermenting waste to methane) to treat wastewater. Anheuser-Busch does it at their breweries because their wastewater is particularly rich. If more municipalities built those at their wastewater treatment plants, then it would be a sizeable amount of carbon-neutral fuel. There are already 1200 municipal wastewater treatment plants in the US that do this according to the EPA, but there are many major cities that do not. https://www.epa.gov/anaerobic-digestion/types-anaerobic-dige...

The energy generated from biogas recovery at Melbourne's two main sewerage plants (~100 GWh) isn't even enough to make them net generators [1].

The main environmental benefit isn't actually from the carbon footprint of biogas, it's the reduced methane and NOx emissions from capturing the gas.

[1] https://www.melbournewater.com.au/water-data-and-education/e...

Ya, but I would guess the story is a bit more complicated. Consider (off the top of my head):

I imagine there's a real concentration problem there. Sewage is incredibly diluted if you think about it (divide your estimate of how much organic waste you generate by the amount of water used in your water bill).

If, instead, houses had grey water systems (i.e. the sink in you bathroom is used to fill up your toilet tank), or if black waters had a separate sewer (sure, not feasible in suburbia), the energy budget would change considerably.

Either way, the affluent is full if nutrients even if we can't recover the energy. Nutrients our soil is rapidly being depleted of (thanks to our modern use of sewers!)

At the end of the day, there's just not a lot of energy in human waste. Poop is what's left after your body has extract all the energy it can from food.

That's a key qualifier though, energy we can extract.

I don't think energy recovery from sewage is feasible, not in the short term, not with our current infrastructure. But either way we should be treating our waste more deferentially in an attempt to recover the minerals 6 billion people poop every day. Except for water, everything in pee and poop is valuable if recovered (urea ->energy, phosphate ->mineral, sulphur ->mineral, starch ->energy)

Instead it all gets dumped to the oceans and the ocean dies from too much nutrients

I don’t think you are correct. A lot of places spread it on crop fields historically and many still do. It can be treated to remove (reduce?) the risk of disease transmission.

Animal manure is very good for plants and many gardeners seek out chicken, horse or cow manure.

Manure is used as a source of nitrogen for crops, not energy. Plants usually get their energy from the sun.

affluent -> effluent. Affluent means wealthy.


I imagine it also greatly improves the air quality for anyone down wind from the treatment plants.

If you want to do this seriously, you could probably do quite well by creating biogas from kitchen scraps:


No, you probably can't. To make biogas on any reasonable scale is at least a village-scale thing; a single family/household cannot easily produce sufficient raw-material to manufacture useful amounts of methane unless you commit to growing biomass just for conversion. (See also another comment below where livestock are involved, so another path to a sufficiency of raw material.)

I was very keen on the idea of making my own biogas (for cooking) when starting out in my self-sufficiency efforts some >25y ago, and the entire sewage system is designed to make conversion to biogas production easy, but the reality is it's just not ever going to produce any significant quantity of methane without some serious supplementation. Add to that, biogas digesters slow down significantly in Winter, even here where we never get freezing temps. In places that experience serious Winters you need to figure out ways to heat(!) the digester to keep it working lest the raw material inputs back up and cause... a mess that will thaw in Springtime with (cough) challenging results.

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.

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.

If you're collecting something that would be produced anyway, it's going to be a net bonus.

Ideally your kitchen waste would go into a facility that properly handles it and will use it for energy production, but in a properly controlled environment (and if that energy production is biogas by avoiding methane leakage as good as possible).

Of course whether that happens depends a lot on where you're living.

Although our municipal green waste gets converted to compost, I recently found out that there is a food waste to energy plant in my city [1]. Going by their numbers, a home can be powered for a year with 25 tonnes of food waste, or 70 kg a day.

The two largest sewerage treatment plants also capture and generate electricity from biogas [2].

[1] https://www.yvw.com.au/faults-works/planned-works/completed-...

[2] https://www.melbournewater.com.au/water-data-and-education/e...

I think in Germany this is pretty standard (both turning organic waste into biogas and collecting biogas at sewage treatment facilities).

And tbh not treating organic waste as some form of resource should be considered a scandal these days, and the only valid discussion to be had should be how to use it (my bet would be that in the long term that will be chemicals and not energy). There is legitimately a lot of talk about the landuse issues of bioenergy, but using organic waste doesn't have any of those problems. It should be an absolute nobrainer.

That ideal is far from happening.

Household waste either goes to commercial composting plants (where the methane produced most likely escapes) or to sanitary landfills, where the reduced biological activity means that the scraps degrade at a much slower rate, but do eventually reduce to methane and other lipids, though possibly at the scale of millennia or longer.

A well aerated compost pile would likely produce less Methane.

Biogas is by definition a product of excess biomass production. The net potential can be estimate by the net agricultural (and perhaps forestry) primary production within a country.

To a rough first approximation based on food intake, biomass is the residual of undigested food caloric energy in the waste stream, which I believe runs at about 25% of the input calories.

You can estimate this for a population by taking roughly 2,000 kilocalories/day * population * 0.25. Ignoring any collection or processing losses, for the US this translates to about 700,000 GJ, 110,000 barreloil, or 200 GWh electricity (assuming no generation or transmission losses, in actuality about 1/3 this amount).

Actual US energy consumption is closer to 45 million barreloil day (equivalent, only 18.3 million barrels of actual oil), or roughly 400 times the maximum amount of energy available in food waste.

There may be other biomass wastestreams available (say: the input feedstock for livestock, pork, dairy, and poultry), though this won't add up to the 400-fold increase necessary as typically the trophic loss is about 10x in a given foodchain level. Even were all US food consumption in the form of animal products, the wastestream would be 40x short of present energy consumption levels.

It's not clear if the artist here is aware of what they're demonstrating, but the process of methane harvesting employed is not dissimilar to how fossil fuels formed in the first place, with biomass settling to the bottoms of shallow seas and, over the course of hundreds of millions of years, being transformed to petroleum and natural gas.

We're presently consuming that bounty at roughly 5 million times its rate of formation. The fact that it takes 8 hours to produce fuel sufficient for 20km of travel is actually millions of times more efficient than the net energy cost of fossil fuels.

Jeffrey S. Dukes, "Burning Buried Sunshine" (2003) details this with exquisite clarity.


I’m curious what moped km per day one could generate with human waste, food and yard scraps.

Here's my rough estimation:

Anaerobic digestion of food and green waste yields ~0.22 toe/tonne of biogas, and manure yields up to 0.04 toe/tonne [1]. (toe = tonnes of oil equivalent)

Australia wastes 300 kg/year/capita of food [2] (across the entire supply chain, from farm through fork)

Americans generate 90 kg/year/capita of yard waste [3]

That's 1.07 kg/day, for 0.24 kg of oil equiv.

The average adult produces ~0.4 kg/day of manure [4], for 0.02 kg of oil equiv.

All up that's 0.26 kgoe/day, or 0.3 L [5] of petrol.

The most efficient scooter I could find (Honda Activa-i) does around 70 km/L (165 mpg)

So optimistically, you could generate 21 moped kilometers per day of biogas. In more normal units, that 3 kW/h or 11 MJ.

[1] https://www.iea.org/reports/outlook-for-biogas-and-biomethan...

[2] https://www.environment.gov.au/protection/waste/food-waste

[3] https://www.waste360.com/mag/waste_yard_waste_4

[4] https://www.emedicinehealth.com/ask_how_much_does_poop_weigh...

[5] 1 kgoe = 1.16 L of petrol

This is actually pretty amazing.

One could commute to and from work and it would be arguably greener than solar or wind.

This made me chuckle. I am guessing he is trying to show how ridiculous our life style is without fossil fuels?

Definitely. This is an art project (ArteZ is an art school in The Netherlands) and the naming suggests a lot of fun! - Slootmotor: already explained in article - Uitsloot: pun on exhaust gas and ditch - Plompstation: pun on gas station and pond/water

Looks more like a proof of concept that you can get enough methane to run a moped from your local ponds.

Not at all. Did you read the article?

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 reaching the atmosphere, where it's economical.

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.

> he's doing the world a favor by burning it

i.e. transforming it into carbon dioxide and water - both greenhouse gasses.

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.


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?”

Water is the biggest contributor to the greenhouse effect (~60% of the total), but that's because it's the most abundant by far (wikipedia indicates about 0.25% globally [0], by mass, which translates to something like half a percent by volume; meanwhile CO2 is 0.04% and CH4 is 0.0002% by volume). And as others mentioned, it's mostly not human-generated, and it stays in the air for a much shorter period of time (on the order of days instead of years or centuries because of a localized phenomenon called, um, rain).

Methane, on the other hand, is much more than 2x as potent as CO2 (estimates range from 21x to 40x the warming effect over the span of 100 years, but most are centered around 25x, when taking into consideration that that methane's atmospheric lifetime is only ~12 years).

You could argue that there's a 3x multiplier in the comparable difference in weight, but you've still got an 8x multiplier. Even if we assume that CO2 and H2O are comparable in terms of warming potential by volume (it's hard to measure H2O for various reasons), there's still a 3x multiplier over that 100-year period, compared to 1x CO2 and 2x H2O.

Why would some molecules be more potent than others? It's a matter of the infrared wavelengths they absorb, but in particular how they cover the spectrum relative to other atmospheric gases. CO2 absorbs strongly in parts of the spectrum that H2O absorbs more weakly, and CH4 absorbs strongly in parts that aren't covered by either CO2 or H2O [2].

[0] https://en.wikipedia.org/wiki/Atmosphere_of_Earth#Compositio...

[1] https://www.epa.gov/ghgemissions/overview-greenhouse-gases#C... - "Pound for pound, the comparative impact of CH4 is 25 times greater than CO2 over a 100-year period."

[2] https://www.acs.org/content/acs/en/climatescience/greenhouse... which depicts the absorption spectra for various gases on the right: https://www.acs.org/content/acs/en/climatescience/greenhouse...

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.

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.

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

I thought that clouds reflected sunlight back to space and had a cooling effect. Interesting that I may be wrong about that.

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!

Never is it claimed to be a GOOD invention, :p

Searching for the terms "secu" and "safe" doesn't yield any results. I know this is more of an art project, but in a photo he's driving through a city. What are the security implications of this?

Also searching for "poly" doesn't yield any results, so I'm left to hope that the is using polycarbonate to provide some kind of safety shielding in case things go south.

Also not on http://uitsloot.nl/sloot-motor/

I don't understand what the security implications might be? It's just the normal gas that's available from mains gas everywhere, in a low-pressure tank. Probably no more dangerous than existing CNG/LPG vehicles.

Much less dangerous as the pressure is very low and the quantity of gas very small.

LPG is usually stored in a sturdy metal tank, and not a big balloon.

LPG can be pretty dangerous in a car when not installed properly…

The amount of methane to make a 50cc moped travel 20km is likely very little. And the tank is huge, so low pressure.

His "Safety testing" video might have something?


Great! Good to know that he seems to care so much about this that he even posts some kind of research videos about it. Good job!

IIRC the average male farts 20 times a day. If he installed a voluntary workplace "collector", he would improve the office environment considerably (as well as improving climate change) and harvest methane for free.

For that special motorcyclist: how about a direct butt plug-in? A former co-worker especially fond of flatulent foods could likely get 10 km from a bean burrito.

I wonder if "TailPipe" is trademarked.

Feel the nitro punch of acceleration.

Isn't this just a low-scale biogas-collector+engine? Biogas is already used in farming and commecial transportation since some decades. So the point here is that there are also other sources we can collect it from?

This remindes me of those guys who collect grease from diners and others foodshops to refine it into fuel for their cars.

Relating to the methane etc. in bogs - https://en.wikipedia.org/wiki/Will-o%27-the-wisp sounds intriguing, curious how common it is.

> “Eight hours of hoeing for a twenty kilometer drive will ensure that it will be the best twenty kilometers of your life.”

True, and highly disruptive of orthodox economic theory which posits the primacy of convenience.

Or the modern presumption that anyone has a better use for eight hours of their time than hoeing ditches and ponds in order to ride a moped the distance you could walk in half that time.

I'm reminded of the biodiesel people of some years back, the ones who'd each hit all their local fast-food places to ask for waste grease so that they could make enough biodiesel to hit all the local fast-food places the next time.

Given that this involves disturbing the bottom of the pond, and that burning methane still produces CO2, this may actually be less environmentally friendly than just using gas.

Methane is estimated to be an order of magnitude or two more powerful than CO2.


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 false, you should have read the link or just looked it up. And on a sidenote CH4 is converted into CO2 in the atmosphere sooner or later anyway.

> 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.

> It takes the young Dutchman roughly eight hours to collect enough fuel to fill the tank and ride his moped for about 20 km. This is not comparable to the convenience of filling up a gasoline tank or charging an electric battery, but that is exactly the point.

This shows the true cost of using fossil fuels has to be payed by something else (our planet) but not by its users.

Wood gas vehicles were, well not uncommon:


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

Saw a few pictures from North Korea using something like that.

It's actually more interesting than I thought!

I both read and watched the video.

What was invented?

Also, on a side note this sort of "environmental solution" reminds me of the 1970's beached whale disposal in Oregon.

edit: reference https://en.wikipedia.org/wiki/Exploding_whale

This guy is clearly a modern wizard.

A solar powered still mounted to the back that dumps methanol and ethanol into a tank would be interesting depending on where you live. If you live in an area with a lot of fruit (California Central Valley) you could ride around for little cost.

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.

Methane is produced from anaerobic bacteria. If you add enough oxygen to the water and make sure the pond doesn't stratify, aerobic bacteria should take over and produce CO2 instead.

What is the yellow liquid: http://move.rupy.se/file/slootmotor3.png

It will be a flame trap.

Gas bubbles through the water so the engine can't send fire back through to the gas bag.

Probably motor oil, these mopeds normally run on a fuel/oil mixture.

True, so he injects the motor oil with the gas so the cylinder doesn't jam?

But has he prooved there is only lubrication oil in there, oil also burns, maybe the methane bubble is just for show and he has actually converted the engine to some sort of diesel/ethanol/any other oil engine! ;D

I want to se the engine stop when the ballon is empty! :\

Also now I watched the video: he spends more energy collecting the gas than it would have taken him to use a regular bike. But fun idea.

Moped is a 2-stroke engine, the fuel is also the lubricant, It won't combust on oil alone.

Are we allowed to just dig up river bottoms? In many places you can get in serious trouble for disturbing wetlands. Were there any permits needed for this?

Disturbing wetlands is sort of the Dutch's thing: https://en.wikipedia.org/wiki/Polder

I've heard of people collecting methane gas from composting toilets. It would probably be a big improvement.

Read the title at first as "Investor harvests ..." and was like holy shit an investor that actually understands how to build something ....

That guy has the perfect, steam punk look to go with his vaporium power autobike.

Cows I know release a lot of methane. I’m but sure if there’s tech to harness that.

I dig this - his travel is powered by his work ethic. Love to see it.

"He calls it “a quest on keeping the combustion engine alive in a fossil free future”."

And why is that a good thing?

That comment seems tongue-in-cheek to me.

But to attempt a serious answer to your question; a large quantity of CH4 is produced in nature which eventually - after about 8 years - turns to CO2 and water in the atmosphere. But carbon in the form of methane is about 30 times more potent than CO2 as a greenhouse gas.

If this hastens the natural process and turns the CH4 into CO2 immediately, then the earth will be subject to less greenhouse effect then just allowing the methane to naturally oxidize.

Seems like learning about the bio system and setting up a methane producing aquarium at home will be easier.

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