Tuesday, February 24, 2015

Paean to the power of poop, a Squirrel Case entry


In his essay The Mariner's Rule, Greer made an aside about his challenge, "daydreaming about the grandiose project that’s certain to save us."  He provided an opening for me that I couldn't pass up.
That reminds me; I have an preliminary entry for your "Great Squirrel Case Challenge of 2015," power from poop.  We can heat cities and provide them with electricity using the methane from sewage supplemented by the waste heat from all the hot water that goes down the drain with every load of dishes and clothes along with every shower and bath.  Of course this is insufficient to the task, as well as actually being practical on a small scale, but my students found it just disgusting enough that it passes the outlandish test.  Of course, if you think it's not grandiose enough, that will save me writing the actual press release.
The Archdruid was encouraging.
Pinku-sensei, it's grandiose enough, and it's also got the benefit of grossness, which is a plus. Write that press release -- or better still, the sycophantic media article.
Deadlines do a wonderful job of concentrating the mind.  Follow over the jump for the fake article.

Power from poop

Every time you use your toilet, you're flushing valuable energy down the drain.

The same is true every time you take a bath or shower and every time you run an appliance that uses hot water.   That "waste heat" from "waste water" could be turned into a valuable resource, heating your home instead of making a sewer steam.

That's not all.  The waste itself can be converted into methane.  Once cleaned up, it can provide electricity or even substitute for natural gas in all its other uses.

Think that's disgusting?  You should see what fracking does.  To paraphrase Steve Martin, energy production is not pretty.

Capturing energy from waste water is not some futuristic dream.  It's happening right now.

Two companies are already manufacturing heat exchangers to capture heat from water going down the drain, as reported by Energy Solutions.  Right now, that water is being used to preheat the water destined for the water heater in commercial kitchens, but similar devices already exist for home use.

The Canadian company Ecodrain makes number of heat exchangers for home and industurial use.  Its smallest product is designed for showers.  The company advertises that its product will save money, reduce ones carbon footprint, and allow its costumers to take longer showers.  That's a win for people, planet, and profit!

In addition to the shower heat exchanger, Ecodrain also manufactures heat exchangers for home and industrial use ranging from one for sewer lines coming out of houses that can use the otherwise wasted warmth to heat the house to large units for the drains coming out of factories, hospitals, and establishments that use a lot of hot water, such as commercial laundries.

That's what's available right now.  In the future, capturing waste heat in all its forms could be a major source of electricity, too.  Scientific American reports that enough energy is lost from industrial processes in the U.S. alone to power 10 American million homes.  A third of that is at less than the boiling temperature of water, too cold for current methods to use to create electricity.

Scientific American also relates that just last year, scientists at MIT and Stanford discovered a way to turn that relatively low-temperature heat into a way to recharge batteries.  Installed in enough factories, the resulting electricity could not only make the factories energy independent, but also export power to the communities, turning waste into profit.

In addition to reusing the heat from waste water, the waste itself can be turned into biogas.  Instead of having the methane bubble away at a sewage treatment plant, it can be turned into a useful source of power.  The sludge can be fed into a digester and the methane captured.  This is already being done at some sewage treatment plants and the electricity being generated is enough to operate the plant, making it independent of the grid.  Scale the process up and it can export electricity to the community.

Michigan State University is already doing something similar, using organic waste, including cow manure, from its farms and food service locations to produce methane to power buildings on campus.  Even better, what remains behind is being used as a fertilizer.  As MSU says, this provides "many benefits, including renewable energy, emissions reduction, landfill and wastewater diversion."  Not only is it good for people and profit, it's good for the planet, too.

MSU has enough confidence in this system that they've built also one for a village in Costa Rica to provide its energy.  It's not just for Americans!

In fact, the Spartans may have the right idea using manure from their model dairy farm.  Animal waste is an ever better source of energy and potentially an ever larger pollution problem.  There are nearly 90 million head of cattle of all kinds in the U.S. and each one of them produces as much manure as ten to fifteen humans.   Add in the 60 million pigs and 8 billion chickens and that's a lot of poop that is now pollution and can be made into power.

So, the next time you flush the toilet, you could be flushing your energy future down the drain.  That's the really disgusting thought.

4 comments:

  1. It pains me to burst your bubble but I toured a poo-poo plant that recovers methane two years ago. It has five huge methane digesters and the methane recovered is sold to the gas company or converted to electricity and sold to the electric company depending on which is more profitable at any given time.

    Sounds good so far. But there is a catch.

    The poo-poo only produces one fifth the power needed to run the plant.

    Energy Provided / Energy Used = EROEI which in this case is: 0.2 / 1 = 0.2

    Divided by one! That has to be the most simple equation I've ever written. It may even be the most simple equation possible.


    The methane digesters:

    Latitude 47 28' 19.2" N
    Longitude 122 14' 20.7" W

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  2. That's what makes this a perfect squirrel case entry. On the surface, it looks good, but deep down, it won't work, at least as advertised.

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  3. It is still a contribution and perhaps with re-design the EROEI can get bumped up a little. On a large enough scale it is worth doing and contributes to a greater renewable infrastructure.

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    1. Oh, I agree. It will capture a lot of wasted energy that can be reused. That makes both parts of this scheme fancy means of energy conservation, not tapping new sources of energy.

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