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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

#151

Post by peterpost2 »

Robadob wrote: post #148
oh_sigh wrote: post #110

Earlier quoted context omitted.

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.

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

#152

Post by noaccnt »

pchristensen wrote: post #124
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),…

affluent -> effluent. Affluent means wealthy.

thnx

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

#153

Post by noaccnt »

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.

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

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

#154

Post by Scoundreller »

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…

> 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.

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

#155

Post by tempestn »

simonh wrote: post #147
fennecfoxen wrote: post #142

Earlier quoted context omitted.

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.

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

#156

Post by okareaman »

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.

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

#159

Post by TrevorJ »

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

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

#160

Post by BurningFrog »

danuker wrote: post #106
tolerant_sol wrote: post #100

Earlier quoted context omitted.

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.

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