How would we sustain food,water, and fuel?

(Larry G) #21

Cost is relative…

For a third world solution where cost and availability are the tightest constraints, $200-$500 per installation is not feasible. For a lifestyle change meant to maintain a 1st world standard of living, it’s pretty reasonable. The average American household spends more than this on entertainment every month.


Which is which I’m working out a cheaper alternative. Not like I have money to waste, or throw at ridiculously expensive replacements.

Don’t need it to pump, so blender parts are cheaper and more feasible.

(George Spencer) #23

Fair enough, a macerator does seem expensive compared to, say, a garbage disposal? I’ll wager a garbage disposal would be pretty durable for this application … turds would be much easier to shred than a carrot. =)


They do use kitchen disposers all over, to prep food waste for use in digesters. If you’re on Facebook, one group on digesters is:

Main people are:
Professor Thomas Henry Culhane of Mercy College
Janice Kelsey

@thebastidge and I are both members. I’ve added a good bit to the files section.

One fella, in Singapore, and I co-designed a digester that is going in for mold making and a half dozen initial demonstrators to be made.

Using digestate is proven for aeroponics and hydroponics, depending on plants, types of inputs, nutrient content and various concentrations/dilutions.

(George Spencer) #25

Spent a few hours following links from Solar CITIES Facebook page … Wow, I did not think biogas was so mature!


I’m working on several simplified, but further advanced designs, at the moment. One will use a triple chamber system and blender parts, like I’ve tried suggesting.


a 30 gallon capacity will hold the feces and an equal amount of water, plus the approximate equal volume of toilet paper pretreated with urine, for 4 people, for 6 weeks, with room to spare. That doesn’t cover all the food waste, or much of the urine, but most of the urine can be used diluted as fertilizer, and for other products.

My initial design for the digester will be self-made using pvc sheet, various pvc pipe fittings, and blender parts. I’ll use an RV flapper-valve type toilet, to minimize water usage. It’ll be followed bu a 30 gallon barrel converted to aerobics, then discharged into an aboveground transpiration/grow-bed, for a zero-discharge system. Excess urine will be handled separately.

(Gavin Brown) #27

Easy… Make it! Use wind, solar, wave and OTEC to produce electricity. Any spare can condense water into o2 & h2, recombine when required. Liquid fuels from biomass as required. Algae farming for gas fuel/ o2 and the biomass after its spent.

(Larry G) #28

Costs more to separate than you get back when re-combining, due to inevitable losses in efficiency. Storing hydrogen is not a static process either. It too, loses efficiency, the refrigeration costs (lots of) energy, hydrogen (being the smallest atom) leaks out of just about any kind of containment system, and it’s dangerous.

(.) #29

Nothing beats practical experience. Writing is easy. Drawing is not so easy.
Physically building objects, machinery and structures is the most convincing.

Just like negative opinions are easy to state, but offering a viable alternative is
more difficult. Whatever, so philosophy is just what it is.

(.) #30

And , yes, hydrogen is flammable. When mixed with oxygen it is explosive.
Hydrogen leaks out of everything, liquid form has to be kept very cold.
For me it is probably not the choice of energy storage.

(Larry G) #31

Making hydrogen and oxygen from electrolysis is very useful- if you need hydrogen and oxygen. Just as a way to store energy… not so much.

(Jordan) #32

Why one company? Let multiple companies do it and compete.