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The Power of Sewage
Eridanis writes ""The waste you flush down the toilet could one day power the lights in your home. So say researchers at Pennsylvania State University who last week revealed they have developed an electricity generator fuelled by sewage." Hey, it seems that EA will have to create a new building for Simcity!"
.... so do lots of other things. What happens when someone flushes a pint of paint thinner or weed killer or heavy metal organic compound down the old toilet?
Biomass technology (energy produced from waste) has been around since the 70's. Though more specific and more refined than its predecessors, there's nothing revolutionary about this.
Don't ask me why I remember this but I can remember a peice on the local news about this a couple of weeks ago, apparently the output (as in eletrical) from the bio-gas is only used to power the rest of the 'farm' and pumping as it stands, but it's hope they could make a contribution to the National Grid eventually.
Somehow I don't think this will replace the >25% of output we currently get from nuclear plants set to expire over the next decade.
If only we could shit uranium.
We discussed a similar high temperature conversion in the past. This alternative process uses high temperature/high pressure water to crack a wide range of complex molecules into simpler stuff. It can convert sewage, toxic waste, and animal byproducts into a mix of combustible hydrocarbons, salts, and water.
The new Microbial Fuel Cell method sounds interesting, but I bet it fails in the field. I'd bet that nasty substances (the odd pulse of heavy metals, detergents, or drain cleaner) would poison the microbial catalysts in this new fuel cell.
Two wrongs don't make a right, but three lefts do.
" ...this system would produce 51 kilowatts on the waste from 100,000 people"
:D
United States 146,583.9 kilowatts
India 533,011.5 kilowatts
China 672,571.3 kilowatts
Clearly, China is the all powerful nation
Ha ha, Amerika, your spacious country is dangerously underpopulated! j/k.
"There is no spoon." - The Matrix
Von Roll has a similar technology called a fluidized bed incinerator which is used to incinerate all sorts of waste, including human waste that is up to 70% water. This is currently being built at the Metropolitan Wastewater Plant in St. Paul, Minnesota, and is already in use in many other places to process organic wastes such as from corn and turkey processing byproducts.
The system essentially works by heating up tons of sand being blown around in a large cyclone tower, and injecting the fluid waste into the whirling vortex. A lot of energy is required to heat up the sand to start the process, but after which the system generates enough power to power the entire treatment plant, and sometimes then some. More info in the white paper.
Yeah it was the thermal depolymerization (TDP) process...supposedly perfected by some company called Changing World Technologies...
I thought that plant next to the turkey-processing place was supposed to be running by now..has anybody heard any follow up on that? You'd think it would be bigger news if it was operating as well as they said it would...
teeker
Right!
About 10 years ago there aws a pig farm just down the road from my grandmother's farm. He ran all the pigshit into a "shit converter" and generated enough methane to run a 10 Kwatt generator that pretty much ran the entire farm. He was still connected to the grid for emergencies and peak demand.
Interestingly enough, anaerobic digestion gets you methane; aerobic digetsion gets you methyl alcohol. So he ran two converters; one supported aerobic digestion so that he could get methyl alcohol to run his tractors. Whatever solids were left went onto the fields that grew the food that he fed to pigs that generated shit... nice closed system.
Disclaimer: I am not a chemist; all of this came from about a 2 hour talk with him about how his farm worked.
That isn't actually as much as it sounds. 51kW for 100k people is only 510mW per person. Yeah, just over half a watt. Now if a person eats 2000 calories a day, that's 8320 kJ in 86400 seconds, or about 96 watts. Which gives us an efficiency of about half a percent.
Je fume. Tu fumes. Nous fûmes!
I would like to see all kinds of technologies that allow private parties to generate electricity become more prevalent. You can decentralize the power grid and open it up as a peer to peer trading network. It's the logic of the internet applied to the outdated logic of the power grid.
Put solar, wind, sewage treatment, and other types of generators in your house. Use what you need and trade what you don't. If you've got a shortage then buy back what you need. In January, south africans can sell solar generated energy to russia. In june, russians can sell it back. Private and commercial ventures alike can create power in large amounts by any means and then sell it in the free market directly to end users and other public entities with large energy demands that are all then free to buy from the lowest cost sources.
Hydrogen fuel cells will also help enable this by allowing the banking of energy for later use and/or trade. Superconductors can improve the efficiency of the whole system and help the private sector economics reach critical mass. Are all of these kinds of technologies going to inevitably converge toward an energy revolution? Between all the bits and pieces it really looks like something is going to come together...
When I was a kid, my dad worked as a mechanic at a sewage treatment plant. After the sewage comes in, it passes through a system called a digester where it sat. The fumes which were collected were mostly methane gas, that was pumped into giant diesel engines that ran generators that ran the digestion system that ran the engines that ran the... Oh dear I've gone cross-eyed. There was still some solid waste left behind however. It was loaded into large spreaders and spread out on large fields and then flattened out to dry. Though about 90% of the stink had gone local residents still complained. So they came up with an industrial perfume called Roto-ban that was sprayed on top to cover up the smell. Shortly after more people complained about the smell from the perfume than the waste, so they stopped using it. What was left over was collected and sold as industrial fertilizer. You could not legally (in the US) use it to fertilize vegitation used for human consumption, but you could use it to fertilize food used for animal consumption (and then they could legally sell the animals as food). So basically HAHAHA (pointing) You eat turds!
Here:
. ht m
http://dnr.metrokc.gov/wtd/fuelcell/fuelcellcam
This isn't a new idea - there are rural homeowners who do it. Micro-turbine hydro seems to be the most popular tech for it now, probably because it has the highest return on investment.
Go find some issues of Mother Earth News, Countryside & Small Stock Journal, or Backwoods Home. There have been literally hundreds of articles over the last twenty years.
Fuel Cells (and you don't necessarily need hydrogen, there are FC's that can utilize methane, natgas, LP...) are really going to revolutionize small projects like this, once the bugs in the FC tech get ironed out and it gets into mass production.
What we really need right now to make this all take off in a huge way is better battery technology. Right now electrical storage efficiency sucks. If someone could come up with a really efficient way to store electricity, we could practically eliminate oil usage for energy production in a couple of generations.
SB
It's old. The more humans I meet, the more I like my cats. At least they are honest.