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Salt Lake City Plan May Turn Sewer Waste To Energy 90

tuxd00d writes "The question goes something like this: How many toilet flushes does it take to power a light bulb? There's really no answer, but Salt Lake City is exploring a pilot project that would convert sewer waste into energy to run a heating and cooling system in a downtown building, city water department official Jeff Niermeyer said."
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Salt Lake City Plan May Turn Sewer Waste To Energy

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  • by chowdy ( 992689 ) on Thursday November 09, 2006 @08:57AM (#16783373)
    This shitty heater never works!
  • by Anonymous Coward
    When you flush the sh*t will really hit the fan...
  • by eldavojohn ( 898314 ) * <(eldavojohn) (at) (> on Thursday November 09, 2006 @09:00AM (#16783403) Journal
    From the article,
    Attorney John Lear's new offices in the Major George Downey Mansion will be the testing ground for the system. Lear, who specializes in gas and oil law, stumbled upon the idea last year while investigating alternatives to traditional heating and cooling systems.
    Does anyone else find it odd that a gas & oil law official is proposing this? I mean, I hope he did his research to make sure that the extra cash spent ensures that this energy is return is worth it. Also, I find it odd that this would be held in a mansion basement and not the local sewage treatment plant where it could eventually done en masse. Aside from watering the lawn, is there a proximity requirement for this particular method of harvesting energy from waste? I wish they would delve more into details but unfortunately all we seem to get is "Simply put, the system would transfer energy from one place to another."

    It sounds like it works similar to the biomass ideas I've heard that are constantly arising []. I would like to see a formal unbiased study done on what process applied to X renewable resources (in this case, waste) is the most efficient in net energy return.

    There have been some recent minor [] achievements [] by a research team at the University of Minnesota (my alma mater) [].

    I'm not sure if it's related to an effort to introduce it to the public []. From that article
    The project includes each utility installing a new boiler, fuel handling system and auxiliary equipment to tie into existing turbine generators. The project will use biomass from a tree farm in Aitkin, as well as right of way clearings.

    Biomass is organic matter (such as wood) that can be processed into energy for heat, liquid fuels or power generation. Biomass can be combusted directly to produce steam for electricity or it can be converted into a gas to power a turbine.

    The boilers will produce 20 megawatts of biomass electricity in Hibbing and 15 megawatts in Virginia.

    The two utilities, working jointly as the Laurentian Energy Authority, hold a contract to sell 35 megawatts of biomass power to Xcel Energy.
    You might laugh but Biomass is important in Minnesota []--although I realize that the current process isn't as BTU profitable as some Brazilian sugar cane plants, but hopefully they can squeeze more and more useful resources out of what was normally considered waste.

    I wonder if it would be possible in the future to engineer plants which when harvested produce an optimal BTU return ... and then make them resistant to the cold cold winters & insanely hot summers of Minnesota. I suppose it wouldn't be safe growing something that's potentially as unstable as impure oil or gasoline though!
  • Send the money down the toilet!

    Seriously though, I'm all for alternative energy, but to really make a difference, the technology has to be cost effective and scalable. That is the ONLY way it will ever get adopted. Wind is moving in that direction and I think nuclear is becoming more viable again.... but many other stuff: solar, wave power, etc... has a LONG way to go.

  • Let's find out.





    What the hell was that?!?
  • Why is it odd to pilot/test on a smaller scale (in the basement of a mansion) rather then impact the production environment (the city's waste water treatment facility)? Wouldn't a proof-of-concept seem reasonable when, as you say yourself, they don't appear to have worked out the details of transferring energy from one place to another?
  • The inevitable (Score:3, Interesting)

    by Ford Prefect ( 8777 ) on Thursday November 09, 2006 @09:17AM (#16783541) Homepage
    ... Cue mass tagging of this article as 'itsacrap'? ;-)

    The idea of powering things from seemingly worthless waste matter isn't new - there's that Swedish train powered by methane from fermented cow offal [], for example. I know sewage works produce a lot of methane anyway, so it's possibly just a matter of collecting it in a cost-effective manner...

    Land-fill sites might be next. I've seen small flares stuck into the ground, burning off excess methane, to stop it collecting to dangerous, explosive levels. Once again, it's a matter of whether it's cost-effective to collect this otherwise free gas.
  • Not that new (Score:5, Informative)

    by kilf ( 135983 ) on Thursday November 09, 2006 @09:18AM (#16783543) Homepage
    The main sewage plants for London (Crossness and Beckton), has been burning most of the capital's sewage to make power for several years. According to the link below, they make a little more power than it takes to run the treatment plant. The Crossness station has a really pretty sinusoidal roof. nNarrative.153/chapterId/3192/Bazalgette-and-Londo ns-sewage.html []
  • by gamer4Life ( 803857 ) on Thursday November 09, 2006 @09:20AM (#16783565)
    During a power outage, just feed tenants some food from Taco Bell.
  • by Anonymous Coward
    it makes the fan turn...
  • This has nothing to do with the water supply. They are going to be using the sewage lines. They dismissed using the water supply, probably for the same reasons you would.
  • Does anyone else find it odd that a the story linked to appears in Whiznews?
  • bindun? (Score:1, Redundant)

    by eneville ( 745111 )
    this article stinks!
    flushing money down the toilet!
    its the shit...!
  • by kfg ( 145172 )
    . . .to really make a difference, the technology has to be . . . scalable.


  • "Just" a heat pump? (Score:5, Informative)

    by Reverse Gear ( 891207 ) on Thursday November 09, 2006 @09:37AM (#16783765) Homepage
    As far as I figure this is just a heat pump, they put lines through sewage that is heating because it is decomposing.
    It is a nice idea for sure, I wonder if this hasn't been done already though.

    People here in Denmark are having heat pumps installed all over the place and people place these water/air lines all over the place to get air for their heat pump a little hotter than otherwise, burying the lines in the earth below frost depth seems to be a normal choice, but if you anyhow do have a dunghill or something like that why not let the pipes run through there.

    Anyhow heat pumps sure is one of the many things that we need to use a lot more in the future, no one technology will be able to replace our use of hydrocarbons, but if we combine all the technologies we have a shot of actually significantly reduce our CO2 emissions.
  • There's never a shortage of bull$hit there...
  • Trick Question (Score:1, Informative)

    by Anonymous Coward
    Obviously, the question is in error.

    A toilet flush produces a certain amount of energy.

    A lightbulb consumes a certain amount of power (assuming a certain average).

    You just can't compare the two. You have to integrate power over time first. A better question would be, "how many flushes of the toilet does it take to power a 15W lightbulb for a year?"

    Then you can argue that it also depends on what, exactly you are flushing, and its energy content. Maybe some people's poop is more effective than others.

  • by Halo1 ( 136547 )
    Actually, everyone can reply, but the replies are invisible (except if it's a reply to your own post and you've turned on email notifications for replies). But even then the "parent" link is broken.
  • really?
  • by kfg ( 145172 )
    Does anyone else find it odd that a gas & oil law official is proposing this?

    He's not a gas & oil law official. He's an attorney. It's a natural fit for him, because as an attorney he's full of . . .

    I wonder if it would be possible in the future to engineer plants which when harvested produce an optimal BTU return. . .

    Sure, it'll just take hundreds of years to grow them.

  • Tag Trolling (Score:3, Insightful)

    by ettlz ( 639203 ) on Thursday November 09, 2006 @09:46AM (#16783919) Journal
    OK, so it's not directly related to shit-power, but why has there been a sudden overload in tag trolling — specifically, adding "itsatrap" to every story on the front page?! This is one for the Slashdot trolling phenomena article. In what way is getting useful work out of sewage a trap?
  • by tbone1 ( 309237 )
    Also, in Indianapolis, the dump is across White River from a few factories and plants. They have a pipe running under the river to deliver the methane to those facilities for very cheap energy and chemical resources. It eliminates a problem for the waste facilities people (big methane buildups are not a good thing) and makes the factories and plants more economically viable. This is a particularly big deal since they are in an area of town that, over the last 100 years, hasn't stayed in the economic forefro
  • Inaccurate title (Score:5, Informative)

    by pv2b ( 231846 ) on Thursday November 09, 2006 @09:50AM (#16783951)
    I RTFA, and it seems they're not actually extracting the chemical energy from the sewage -- rather, they're just installing a heat pump to exploit the temperature differential between the sewage and the ground.

    Now, using a heat pump might be rather novel in itself -- but extracting energy from sewage is nothing new. We've been doing this in Sweden for quite some time now -- except chemically. Here's a random link with some information about one such installation ... []

    The resulting biogas is used to replace natural gas in different applications, and we have for quite some time had Bi-Fuel vehicles that can run compressed biogas as well as gasoline, that enjoy certain tax benifits. Also, I seem to remember that a new residential area in Stockholm, Hammarby Sjöstad, is getting a biogas system for heating (and maybe for cooking, I can't remember)...

    Either way. Extracting energy from sewage is not a new idea. Extracting heat energy from sewage using a heat pump might be a novel idea, but it's not really any new exciting technology, just a rather clever application of existing technology. Calling it "turning sewer waste to energy" is inaccurate, because the actual sewer waste isn't consumed when you do just, you just cool it down.
  • by Fzz ( 153115 )'s been able to reply to comments.

    Are you sure?

  • Gives a whole new meaning to the term "moonshot".
  • This shitty heater never works!
    Tea. Earl grey. Hot.
    Wouldn't that be a good thing if you had planned on making tea?
    "From some reason my Earl Grey's a bit darker today..."
  • by willy801 ( 161198 ) on Thursday November 09, 2006 @10:01AM (#16784115)
    If you didn't notice this article is a summary from a slightly more detailed article at: []
  • um.... no, I haven't noticed. :-)
  • I was troubled that the science of this plan was lost when Tom erased it from the Fun-Puter. I'm glad his idea is being implemented in SLC (though what about Jefferton?)
  • by Ancient_Hacker ( 751168 ) on Thursday November 09, 2006 @10:05AM (#16784167)
    In case you didnt get it, some bozon is suggesting they can heat a building with sewer water thbat's at 65 degrees.

    As they said on the MST3K parody of "The Mole People":

    "Oh NO! Light just slightly brighter than what we're accustomed to!"

    You cannot "heat a building 95% of the time" with a temp lower than your desired temperature. Maybe the soft-pedalled HEAT PUMP can. And with water five degrees warmer than the groundwater, the heat pump will be about 1.2% more efficient. Which can never pay off the added cost, not even the interest on the cost. No way, no how. They'd be much better off spending the $20K on a more efficient heat pump.

  • Yes, it's certainly terrible how we can't reply to comments.
  • O RLY?

    (Testing, testing, 1 2 3, testing...)
  • Already done (Score:4, Informative)

    by StompmotS ( 455206 ) on Thursday November 09, 2006 @10:10AM (#16784237)
    This is already done in atleast one city in Sweden, the heat in the cleaned waste water gets transferred to a district heating system by a heat exchange system. And the then cooled down waste water (just above 0C) is used again as district cooling to a hospital.

    The methane is usually used to power the waste water plant itself. Also often used as fuel in busses and cars.
  • I think its great that people are thinking of ways to recoup some of the energy from waste, but one thing we need to consider is failure cases. If this technology works and we become reliant on it, failure of either the sewer system or the energy system could result in outages. By piggy-backing systems we create more places for a failure to creep in break the system.
  • It really makes you wonder what that smell is when you turn on the heater on the first cold day in the fall.
  • Well, is it broken? Won't know until I try.
  • by catprog ( 849688 )
    solar is almost there [] (cheaper then mains when there in full production )
  • by vuo ( 156163 )
    It's always interesting to see how posters on Slashdot are reinventing the wheel in environmental issues. For example, municipal waste is treated in an anaerobic bioreactor in ASJ Stormossen waste treatment plant in Mustasaari, Finland. Landfill biogas is also collected. A 1998 report. []

    A major problem with eco-friendly technology is the relatively undeveloped state of most of the world. Processes like these are novelty in America and practically unheard of in Russia, for example, even if they are becoming c
  • by Zaatxe ( 939368 ) on Thursday November 09, 2006 @10:20AM (#16784385)
    What about the "clean energy" idea?
  • by ohearn ( 969704 )
    The TVA (Tennessee Valley Authority) is already using some methane plants like this from sewer waste for a small part of it's power generation. It has already been proven a usable, cost effective technology, but I don't know how well it scales up. Of course they have also been installing wind farms and solar sites for the last couple years too.
  • Who run Bartertown?


  • by Zaatxe ( 939368 )
    No, I haven't noticed...
  • This is true of ALL energy sources. If all the energy from all the sources is put on this thing called a "power grid" and the grid is well designed, then the system can survive isolated failures here and there. If the energy is used on-site as a supplement for grid power than failure means things merely get more expensive until the system is fixed.
  • by Zaatxe ( 939368 )
    Hey, don't be so anal-retentive! We are in a power shortage here!
  • I wonder (Score:2, Troll)

    if they could tap into the stream of bullshit coming out of SCO...
  • WHIZNews? (Score:3, Funny)

    by tmh - The Mad Hacker ( 962953 ) on Thursday November 09, 2006 @10:36AM (#16784691)
    Does anyone else find it funny that an article on sewage is on an Ohio site called "Whiz News"?
  • Ever heard of a sewer trap []? ;-)
  • Landfill gas (approx 40% methane, 30% CO2, 18% N2, 2% O2) has been used for years as a fuel to run gas engines. The major problem is that it comes loaded with water (typically saturated) and siloxanes (forms SiO2 or glass during combustion). Pretty much it makes a very 2nd rate fuel. However with some cleaning, scrubbing, and some refrigeration, you can nearly everything except the methane, and sell it as natural gas (great fuel compared to gas or diesel). There are companies right now that do that very
  • Feh. It's a good idea, but the simplest thing they could do is dilute / liquefy the sewage and pump it through a FOX reactor. That's what I do, and a day's worth of poo provides enough heat energy to reduce my heating costs by about $150 / year. Not much, mind you, but it was dead-easy to build. If I buried the system, it would be more efficient. It's largeish; if I had a blended human available to me, I'd be able to toss him in.

    For those confused, a FOX reactor is simple: Essentially, you're pumping o
  • ...Extracting heat energy from sewage using a heat pump might be a novel idea...

    Nope, not that either. Translated from (warning: only in swedish) NI-4027_.aspx [] : "...with heat pumps we extract energy from cleaned sewer water and we also handle waste heat from industries and garbage burning..."

    I heard about the sewer water heat pumps in a radio program a couple of years ago. Apparently it's successful enough that they get visits from people interested i

  • by jbengt ( 874751 )
    The new high school around here (Antioch, IL) uses methane from a nearby landfill for energy. I'm not sure how much they get from it, or what it cost, but in the long run it's a better idea than spending more and more to drill for every last bit of natural gas left in the earth.
  • Really all they are doing is using the sewer system as a large heat source/sink. Nothing really new here. They might be getting some extra heat out of the biology that is happening in the sewer as the effluent goes by, but its not like they are using the waste it self.

    Additionally, they may be just moving the heating/cooling problem somewhere else. If they are using any sort of digester's for treating the sewage, the city may need to add/remove heat to bring the sewage up to the best temperature for the

  • It's always interesting to see how posters on Slashdot are reinventing the wheel in environmental issues.

    Actually, it was simply some quickly-typed padding to disguise the real intent of my comment - which was to get the 'itsacrap' tag in use. Successes:
    1. The article is now tagged with 'itsacrap';
    2. I got a +1 Informative moderation;
    3. Any dissent is being hidden by Slashdot's current reply-hiding ... issues.

    Twisting the Slashdot populace to my nefarious will? Absolutely! ;-)

  • At last, the routers in charge of series of tubes will be powered by a discharge from a series of tubes... And a septic tank truck!
  • Send the money down the toilet! Seriously though, I'm all for alternative energy, but to really make a difference, the technology has to be cost effective and scalable. That is the ONLY way it will ever get adopted. Wind is moving in that direction and I think nuclear is becoming more viable again.... but many other stuff: solar, wave power, etc... has a LONG way to go.

    This kind of system in REAL scale is already viable and implemented in Gothenburg for example. The recovered energy from sewage water wit

  • by Steffan ( 126616 )
    ... Cue mass tagging of this article as 'itsacrap'? ;-)

    That was my first thought, too... :)

    ...and my tag suggestion as well
  • Columbus, OH had this method in place already. It has been an ongoing project for THE Ohio State University.

    The the fact that waste "digestion" produces methane has been known for years.

    What got in the way in Columbus was the environmentalists that think that producing our own methane to consume is hazardous to the environment. They stopped the process, and now the solid waste is mixed with mulch and topsoil to create a "Super Fertilizer", which citizens can pay for and use in their landscaping and gardens
  • by jbarr ( 2233 ) on Thursday November 09, 2006 @12:10PM (#16786457) Homepage
    Instead of the sh** hitting the fan, it will run it!
  • My god, do you realize how much ethanol we can produce by harvesting all the corn? Brilliant!
  • SLC is one of those homogenous communities where 60% of state of Utah population lives. This proves a test bed for wild hared ideas from marketing to engineering and public acceptance.

    Its also one of those places where the government is available at an affordable cost to approach schemes like this one where anywhere else it would have an EIR, DOE and USC regs to begin an introduction.

  • Methane from the DC sewage plant was used to heat the Naval Research Lab where I worked for years. One problem is the methane has quite a bit of air and CO2 in it so the facility where it is burned must be able to adjust the air to fuel ratio dynamically. We were next door to sewage plant so connecting to the methane source was no big deal. Of course when the wind came from the south we certainly knew who our next door neighbor was.
  • by d_54321 ( 446966 )
    Thus the answer ("There's really no answer") was in error also. There is some number, probably between 1 and 1 million, that will fit the query. Finding the answer may be tricky, but to say it doesn't exist is just wrong.
  • This! bee ayy enn ayy enn ayy ess

    Hey it's no worse than the other shitty jokes in this thread.
  • Supposing
    1. they channel the effluent directly into the Salt Lake
    2. they pass a law mandating that everyone flush at the same time(s)
    This should create enough wave energy to extract drinking water [] for the city.
  • Those of you commenting "my city of X in Y country has had this for years!" have not read TFA.

    Burning the methane that is a byproduct of one form of wastewater treatment is neither novel or new. Many, if not most, of these types of wastewater treatment facilities produce a net energy surplus, which is more often than not inputted to the power grid. If you live in a modern city in a developed nation, it would be unusual for your city not to have one or more of these type of facilities.

    But that is not what
  • "From some reason my Earl Grey's a bit darker today..."

    This coffee tastes like shit.

    It is shit.

    Oh. It's a bit nutty.

It seems intuitively obvious to me, which means that it might be wrong. -- Chris Torek