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!"

Comments

slightly different approach....

[tanveer1979]

I am aware of Bio-Gas plants which are used in villages in India. The Animal waste is dumped into the "pit" Methane is released and it is used for cooking. But I guess this method is more efficent.
Good for farms where lot of animal waste is there

Re:slightly different approach....

[robslimo]

If you have an all electric house (many do) then your central heat and air or baseboard heaters would get pretty close to that range. Add in hot water heaters and electric ranges, then YES, it's very easy to hit that kind of usage.

Re:slightly different approach....

[Anonymous Coward]

That's not entirely fair. My house used a lot of air conditioning and we averaged 2kW last year (1500kWh/month).

Of course the power generated here would probably be used to run the treatment plant itself. As the article says, may people can't afford the power to run such a plant, so a self powered one could really help.

Re:slightly different approach....

[qtp]

Locate the plant where the waste is being treated, like they do already in Lithuania Germany and Oregon.

You are already moving the sewage around as it is, so that expense is already there. The waste output of the biogas fermener is much safer than the sludge that existing sewage plants produce, and it can be further composted to produce safe, high quality, organic fertilizer.

There are also existing farm waste facilities (as was previously discussed here on /.) and existing technology to tap land fills in the same manner. It's energy that can be easily converted to a usable, transportable form (electricity) that wopuld otherwise go to waste. The gasses that are being converted are greenhouse gasses (mostly methane) that are not readily sinkable, and the waste products from the fuel cell are only (easily sinkable) CO2 and water.

The other implication of this technology that is less spoken about is that it decentralizes the source of energy away from the fossil fuel companies and spreads the profits closer to the community where the energy is being produced, either through lower costs for waste treatment, or through direct profit from the sale of the electricity if the facility is privately owned. This means lower costs for energy and lower trade deficit.

It's a winning situation for those who live in communities that take advantage of this, and the only people who lose out are the energy companies.

Electricity from Waste

[eples]

Something similar has been around since the 50's called "digesters" that use natural waste and the methane byproduct to power generators. It may have been invented at Penn State as well, but they are expensive so there are only about 20 of them around the country.

Re:Electricity from Waste

[ross.w]

IAAWWE (I am a wastewater Engineer)

Actually most sewage plants have a digester in them (or several).

Most Sewage Treatment Plants that have anaerobic digesters (the kind that produce methane) simply flare the gas off, because the quantity of gas produced doesn't warrant the expense of setting up to re-use it.

Seafield Sewage Works in Edinburgh, Scotland does though. It was completed in 2000. If you fly into Edinburgh airport over the Firth of Forth, you can see a row of six large pink tanks near the docks. These are the digesters at Seafield. (The reasons why they are pink are complex and architectural, not functional).

Bondi STP in Sydney used to re-use methane for generating power the 1960s, but the the technology was primitive, and the sulphides in the gas made the engines expensive to maintain and they were abandoned.

Now in Australia, with green energy credits on offer, many water authorities are having another look at making use of their methane.

Re:Electricity from Waste

[kfg]

Digesters have been around for about 100 years. During WWII with gas rationing they became quite common, one version even coming on a trailer you could pull behind your car while collecting manure, and then run your car from.

During the gas crunch of the 70s digesters popped up all over the place and there was hardly an issue of Mother Earth News that didn't have some new design/application of a digester featured in it showing how you could power your farm/homestead on shitty methane.

There are still thousands, perhaps tens of thousands, of digesters scattered across Americas rural areas. Virtually all of them are built by the owners out of scrap materials for nearly nothing.

Perhaps there are only 20 of this expensive commercial variety. A lot of companies like to make money by taking old ideas that people in general have forgotten about, plate them in chrome, and sell them as the latest technology for a premium price.

Go to the library. See if they've got back issues of Mother Earth News from the 70s and 80s. Lots of good digesters ideas in there, although often a bit crudely implimented.

The mere idea of excrement for fuel energy goes back to God only knows how long. It's certainly prehistoric. The Plains Indian relied on Buffalo Chips for fuel, and the Indian Indian still does today.

Latrine Officer was one of the most important posts in Napoleon's army. His job? To retrieve human excrement. It was too valuable an energy source to waste. They used it to be able to make their own gunpowder as they traveled, which is one of the reasons that Napoleon's armies seemed to be able to pull off almost magical feats of translating themselves from one location to another and arrive ready to fight.

Shit is energy. We know that. We've always known that. We've known that that energy can be extracted as natural gases and used to run combustion engines and turn electric generators for over a century. It's news so old it's boring.

It's even a reasonably viable way to go about making energy, if you live on a small farm with lots and lots of animals producing lots and lots of shit you need to do something with.

For city dwelling humans, well, it will never be anything more than a suppliment to other forms of energy. Something you can use because it's there, but nothing to be relied upon.

Why? Well, how much did you shit today? Does that amount of shit convert into the electricity you used?

Not even close.

You'll need a lot of other animals who don't watch TV shitting for you as well. Like on a farm, say.

And nevermind the fact that most of the shit (including human) is more valuable as a fertilizer (which is where much of the treated sewage is going right now) than it is as a fuel, so you're invoking the whole food for fuel argument. It may be better to burn that fuel we can't eat, or use for food production, and eat the fuel we can.

KFG

Re:Electricity from Waste

[qtp]

And nevermind the fact that most of the shit (including human) is more valuable as a fertilizer

The biogas fermenters produce fertilizer as well as gas, and it's much higher in nitrogen content than if it had not been reduced in the fermener.

It's not an either-or proposition.

The using the fuel cells to convert the energy is far more efficeint than burning natural gas. Even the most efficient gas burning plants (gas turbine engines driving alternators for generation) are only 40%-45% efficient (at most 45% of the energy contained in the natural gas is converted to electricity) while fuel cells currently available are capable of converting 85% of the energy available in natural gas to electricity, and the rest is converted into heat, some of which can be used to accelerate the fermentation process, or to heat the facility.

Why? Well, how much did you shit today? Does that amount of shit convert into the electricity you used?

So maybe I only shit out about half a watt today, but over the years that adds up, and in total, the city I live in shit about 773,000 watts, in a year that's 282,145,000 watts that might just keep my sewer bill from rising.

It may be better to burn that fuel we can't eat,

As I noted above, burning is a very inefficient method of converting chemically stored energy to a useful, transportable form. Fuel cells are far better at generating electricity than the power plants we now rely on, which first need generate heat (and lose a fair portion of it up the flue), then pressure, which is redirected into torque, which moves an alternator. Every step of the process loses energy either through conduction or to friction (or both, steam has friction too). Fuel cells are able to be more efficient due to a more direct path by which the energy is converted directly from chemical energy to usable electricity.

and eat the fuel we can.

Use the compost produced by the fermenter to fertilize the fields (after first using the excess heat produced by the fuel cell to accelerate a secondary aerobic decomposition at 145 degrees F). It will be a highly efficient fertilizer due to the removal of much of the carbon during fermentation, leaving behind readily available "fixed" nitrogen that plants can use. Reduced dependance on chemical fertilizers and safer fertilizer than is currently produced from sewage sludge.

These ideas bring the community (and man) back to being a part of the environment in which he exists, a part of nature as opposed to battling against it. If we can reduce our impact on the environment and get it to pay for itself, then this is a winning proposition.

Reminds me of an article in Discover

[MrPoopyPants]

This article got me pretty excited about the future of waste/energy. I'd love to see those piles and piles of junk and biowaste turned into useful energy.

The conspiracy theorist within me fears that these types of technologies will not take off because oil companies have so much power.

Re:Reminds me of an article in Discover

[the_2nd_coming]

yeah, it was mentioned on Fox news by some Democrats complaining about how money was being "wasted" to turn Turkey parts into energy.

AFAIK it works, and it works even better for stuf like oil sand, allowing the processing of the petrolium products from the sand which was never possable before.

Biogas

[GillBates0]

India's been using cow dung and other cattle waste to make biogas for a while now. The greatest benefit is that it's clean and a renewable energy resource.

Biomass Energy is produced by burning the solid Biomass fuels (green plants, agricultural residues, carbonaceous waste, wood etc). Direct burning of Biomass in an efficient manner causes the energy loss. But through Gasification programme , Biomass is converted in to high quality of gaseous fuel through Gasifier power plants. In the Biomass Gasifier , Biomass (a solid fuel) is converted into gaseous fuel, called producer gas formed through a series of thermo chemical process. The producer gas mainly consists of carbon-monoxide, hydrogen and nitrogen gas. The gaseous fuel energy is used in several applications.

Another reason not to eat beef! Let 'em live and generate shit...err energy.(Just kidding, it's a joke, laugh).

Article is based on a false premise

[HotNeedleOfInquiry]

The permise is that sewage treatment plants need external power to run the aeriation blowers. The reality is that many plants use methane from the digesters to fuel engines that run the blowers. Old, simple technology that's relatively cheap and bulletproof.

Old News for those in rural areas

[backtick]

http://www.energy.state.or.us/biomass/digester/dig estech.htm

Lots of places have these; I see someone say "There are only a few in production" fairly often, but this is incorrect; there are more and more every year. Dairy farms are using them in large numbers, but the city of portland has a fairly large one (see http://www.energy.state.or.us/biomass/fuelcell.htm )
that processes the residue from 82 million gallons of wastewater a day.

As an example of the economics, see:
http://www.eco-farm.org/sa/sa_dairy_synopsis _diges ter.html#eco

Payback in 6 years. Not bad, considering lots of places give grants, as these help cut down on groundwater pollution. You can have payback in 3 years, and then start making money on the juice you sell.

Re:Biomass

[greenstork]

Except up until this time, it took more energy to process waste than you got out of it.

Re:I don't think this is any new.

[FooAtWFU]

The local wastewater treatment plant has generators to produce electricity from the gas they collect. But, as I was informed while on a tour of the facility, they don't use them. It is actually cheaper for them to buy electricity from the power company than to use these generators which they already have in place.

This says something about the cost-effectiveness of current electricity solutions.

I work in the sewage industry and this is old news

[Phelan]

We have been making power with sewage for a very long time, methane harvesting to run generators has been around for years, plants can power their equipment plus sell some surplus...
or with our product they can do it at a rate that is up to 60% more efficent...
Shameless plug: Premier Agritech, Inc.

Nothing new.

[Anonymous Coward]

This is nothing new. Here in City of Calgary, at the Bonnybrook Wastewater Treatment Plant, the power requirement can be entirely self-sufficient.

All of the solids from the sewage is pumped into a digester, where anaerobic bacterias break down the solid and produces methane, which is burnt to produce power. All UPenn does is prouduce energy on a larger scale.

Biogas is tripleplus good

[Jeremiah Blatz]

First of all, it converts waste product into electricity. But secondly, instead of sewage decomposing into methane, it decomposes into C02, which is a much less effective greenhouse gas. Additionally, the resulting by-products make a good, smell-free compost.

Here's a blurb about a biogas plant in Oregon

There is no Maxis

[Perianwyr Stormcrow]

Just like there's no Bullfrog or Origin.

EA has eaten them all.

OT question: Why not dual flush toilets in USA?

[tetranz]

In my former part of the world, nearly all toilets in homes are dual flush to save water. They have two buttons, one gives a half flush, the other a full flush. Its not rocket science to figure out when you need which. An american visitor had not seen this before.

Now that I live in the US, I wonder why such technology doesn't exist here. It seems like a much better way to save water than the problematic 'low flush' toilets common the US.

It's not a digester, people

[lesterhv]

To everyone who keeps saying digesters are nothing new; my greatgrandfather pooped into a digester and heated his house, etc. RTFA!

The article is talking about a microbial fuel cell (MFC) that directly converts the energy to electricity.

It is a first, since previous ones ran on glucose.

Something back is better than nothing back

[ciphertext]

The average person defecates how many times per day? I didn't see it in the article, so I'm assuming that this was the projected measurement of 1 defecation per person. That means you get .51 watts from 100,000 feces. Assume that upon average, those 100,000 people defecate once per day. It is possible that some people defecate less than once per day and others defecate more than once per day. You basically get 2.04 Mw a day for a city of 4 million. That would be electricity bought and paid for by the sewer system that could be used to assist in the operation of the treatment facilities. Perhaps the savings would get passed on to the home as a reduced sewage handling fee.

It's being done already

[st1nky187]

Last summer I went on a field trip to a sewage treatment plant. The power to run the plant comes solely from the methane they harvest. I asked about whether they sent any of the power back out to the grid and the guide said that they didn't generate nearly enough to do that. So, unless suburban New Yorkers have a lower methane output than everyone else I'm pretty skeptical that this would be really feasible.

Re:Just doin' my part..

[Shakrai]

As yet his design is only producing a tenth of what he calculates its potential power output could be. Even so, if scaled up, this system would produce 51 kilowatts on the waste from 100,000 people, Logan says. He hopes to be able to boost its efficiency by increasing the surface area of the anodes or by finding more efficient anode material.

Hmm... that works out to about 0.51 watts per person. If he attains his promised tenfold increase it's a whole 5.10 watts -- or just about enough to charge my cell phone.

Not saying it isn't cool but where's the value in this? To quote another line from the article:

Many developing countries urgently need sewage processing plants, for example, but they are prohibitively expensive, largely because they use so much power. Offsetting this cost by producing electricity at the same time could make all the difference, says Bruce Logan, who led the development team at Penn State.

Do they really think producing a whole 5.10 watts from one person's output is going to do anything? True it'd be neat to see that electric folded back into the grid (that's 5.10 watts that doesn't have be generated by burning coal or gas) but is this really going to pay for itself? I'm willing to bet that most sewage treatment plants use more then 5.10 watts per person's amount of waste.

Re:So that's where it goes...

[kfg]

Yes, there is something woefully wrong with those books. They are oversimplified for their ignorant target market, oftentimes by members of that target market themselves who have no deep understanding whatsoever and are merely cribbing from other such books with no deep understanding.

They do ignore waste, such as that found in excrement and the the heat put off by the body, but that's because that waste is of no interest to them.

Nontheless they do manage to get some of the crude details right. Those charts ignore waste, but not by not taking it into account, rather by simply ignoring those calories not actually consumed by the body in producing useful energy.

Yes, I can can power myself on my bicycle for half an hour at 15 mph or so on the fuel contained in a single chocolate donut. Three chocolate donuts will drive me at 25 mph for an hour or so. Substitute about three large bananas for each donut if you like. This is one of the reasons I prefer to bicycle rather than drive.

The human body is an astoundingly wonderous device for turning hydrocarbons into mechanical energy. Just how wonderous can be seen from your own observation, a good deal of the chocolate donut ends up as waste in the urine and excrement, and yet I still drive my bicycle with what I've absorbed for half an hour.

Pay no attention to those stupid calorie counting books. If you want to the know the real deal, explained in hard scientific fact, but written for the intelligent layman, go to your library where almost certainly find these works:

Aerobics. The groundbreaking work itself, based on Dr. Kenneth Cooper's work with training in the military.

Move on immediately to Covert Bailey's Fit or Fat . Covert is formerly a professional sports bum, and currently a Doctor of Exercise Physiology, with an absolutely wonderful way of expressing his knowledge for popular consumption. He's the Carl Sagan of exercise and diet. Read the book, but if your library has his tape series, watch them. If they don't, request them.

From there go to the bicycling science books of Dr. Edmund Burke (also a Doctor of Exercise Physiology), the record holder for bicycling from Buffalo to Albany, NY (14 hours and some minutes. 320 or so miles). These are bit more hard core, but still intended for popular reading.

Supplement with MIT Press's Bicycling Science and Engineering. This is a general lay scientific work on human power generation and the bicycle, the most efficient means of harnessing such power.

If your interest is, or becomes, more in depth than these books cover they are full of references to the orginal studies they are based on.

Then go buy yourself a bicycle, a treadle sewing machine, a wind up radio and a shakable flashlight. These are the most wonderous of all of man's creations so far. People are lazy, so they have spent most of their time developing technologies to avoid using their muscles, but if you combine high tech with muscle power you can accomplish amazing things, and all without foreign oil.

Not to mention the benefits to strength, health, and general fitness.

KFG

Re:Another Version of This Concept

[dbIII]

I'd bet that nasty substances (the odd pulse of heavy metals, detergents, or drain cleaner)

It's simple, like the current methods it will not be a one step process. Floculation and gravity seperation can get rid of heavy metals, and high concentrations of petroleum products or detergents can be dealt with too.

Some oil companies use various bacteria to deal with their waste water, and they have methods to stop spills into their waste water system from killing all their bacteria.

Los Angeles does this

[angst_ridden_hipster]

The Hyperion Sewage Treatment facility, down over Dockweiler Beach, dumps out sewage-related gasses to the Scattergood Power Station.

The best document I can find online today suggests that Scattergood generates 50 Megawatts. I seem to recall having seen other online documents that provided a lot more detail -- it's possible that those documents have been taken down for "security" reasons.

In any case, it's converting one set of pollutants (sewer gas, methane, etc) into another (CO2, NOx), and generating power in the meantime.
Without knowing all the details, it seems like a pretty good idea to me; there are probably aspects that I don't understand that might change my views.