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

Post by toomanybeersies » Tue, Jul 13, 2021, 6:16 PM UTC

noaccnt wrote: post #113

toomanybeersies wrote: post #93

Earlier quoted context omitted.

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),…

Post by lostlogin » Tue, Jul 13, 2021, 6:21 PM UTC

toomanybeersies wrote: post #131

noaccnt wrote: post #113

Earlier quoted context omitted.

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),…

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.

Post by toomanybeersies » Tue, Jul 13, 2021, 6:26 PM UTC

pjc50 wrote: post #45

qwertox wrote: post #34

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.

Post by jhgb » Tue, Jul 13, 2021, 6:50 PM UTC

yunohn wrote: post #101

jhgb wrote: post #82

Earlier quoted context omitted.

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 bes…

> Solar isn’t exactly something you can make I think “make” is the important part here, not buy and install.

Post by Semiapies » Tue, Jul 13, 2021, 6:55 PM UTC

hn_throwaway_99 wrote: post #84

Cthulhu_ wrote: post #74

Earlier quoted context omitted.

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…

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…