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Banana Methane Powered Cars, Pig Poo Power And Other Uses For Biogas
Posted by Big Gav on March 19, 2008 - 8:13pm in TOD: Australia/New Zealand
Topic: Alternative energy
Tags: australia, banana methane, biogas [list all tags]
Powering transport using liquid petroleum gas, compressed natural gas or fuel produced by gas-to-liquids processes are options that have received varying amounts of attention in recent years as the oil price climbs ever higher. While shifting dependence from one fossil fuel to another doesn't make a great deal of sense when you take peak oil and gas into account, there is a renewable option for producing gas - biogas.
One recent example of biogas use in Australia is a pilot project by horticulture company Growcom to convert banana waste into biomethane, which will then be used as fuel by cars converted to use compressed natural gas and by a generator for electricity production.
The processing plant uses an anaerobic digester - in trials, the banana waste produced maximum yields of 398 litres of methane per kg of dry banana. With this yield, 1 ton of bananas per day can generate around 7.5 kW of electricity - enough to supply six to eight modern households.
Growcom board member Keith Noble says, "An over-riding principle of the project has been to use locally available materials and expertise wherever possible. The system must also integrate with existing farm practices. If on-farm digesters are to have a commercial future they must add to farm efficiency and be simple to operate."
Given the volume of bananas required to produce the gas, banana power will only ever be a niche solution (something the people involved readily admit), but it is an example of how waste streams can be used to produce biogas - which has the important benefit of not diverting food (or arable land) to fuel production - one of the major criticisms of present day biofuels.
An important additional benefit is that methane is a potent greenhouse gas, and thus capturing it and burning it helps from a global warming point of view.
Of course, Banana waste is just one type of agricultural byproduct that can be diverted to produce biogas - there are a wide variety of other byproducts from farming and the food industry that can be captured and digested in a similar way (wood chips being another example).
Pig Poo Power
Another niche source of biogas that has considered in Australia is from animal manure - specifically pig poo. This seems to be part of a worldwide trend, with countries as far afield as Thailand and South Korea also harnessing the foul odours and putting them to good use.
Famed Kleiner Perkins Caufield and Byers venture capitalist John Doerr is also getting in on the act, looking at pig farms in California's Central Valley for opportunities.
Pig's aren't the only animals producing large amounts of ordure that could be used for biogas production - other animals producing copious quantities of potential feedstock include cows (which could help solve another problem - burning mountains of cattle manure), dogs, chickens, turkeys (whose output is being burnt directly in biomass power generation facilities in the US, which has received criticism for both pollution and for burning material that would be of use for fertiliser) and zoo animals.
It isn't just the animal world that is capable of providing fuel of course, people can too. A Rwandan prison uses waste from the inmates to help power the prison.
An Indian company called Sintex is even marketing an at-home biogas digester, with hopes of solving India's energy and sanitation problems in one hit. These plans have the enthusiastic backing of the WTO (World Toilet Organisation). A one-cubic-meter digester (initially filled with cow dung to provide the bacteria required) can convert the waste from a four-person family into enough gas to cook all its meals and provide sludge for fertilizer for around $425 - paying for itself in energy savings in less than two years.
Similar schemes are in use in many other developing nations (an Energy Blog commenter once referred to the developing world as "one large zone of 'stranded biogas'").
Landfill Gas
Another widespread use of biogas is capturing the gas produced in landfills for power generation - Australia already has a number of plants in use, and a large number of developments are underway in the US capable of generating hundreds of megawatts of power, with an estimated 700 sites capable of being used for this purpose.
One heavy user of landfill gas is General Motors, which has reduced its consumption of natural gas by around 25% since 2000 by replacing it with gas from landfills. The University of New Hampshire is getting over 8% of its energy from landfill gas. The city of Sao Paulo in Brazil has a 23 MW landfill gas plant in operation.
Biogas In Europe
Europe seems to be the leader in the production and use of biogas.
UK studies have shown that biogas is much cleaner and more efficient than biofuels for use in transport - and also allows farmers to become energy generators rather than just commodity producers.
According to an EU well-to-wheel study of more than 70 different (fossil and renewable) fuels and energy paths, biogas is the cleanest and most climate-neutral transport fuel of all.
Some examples of biogas use in Europe include:
* Austrian drivers can fill up their CNG cars using biogas made from grass.
* Denmark has more than 50 biogas plants in operation.
* The Netherlands is generating biogas from sewage treatment plants and feeding it into the gas grid and to fuel cars.
* Sweden is producing biogas from wastewater treatment plants and and using it to generate power and to fuel buses and trains.
* Germany is producing biogas from maize and using it in combined-heat-and-power plants (the French have developed a giant maize variety specifically for biogas production).
The German government is considering feeding biogas into the country's natural gas network (ironically, the main obstacle to this has been that biogas is too good for the network - exceeding Germany's upper limit on gas heating value, something the German Greens and farming lobby are trying to have fixed).
According to the government, locally produced biogas could supply up to 10 percent of Germany's total gas consumption by 2030. Germany is the largest producer of biogas in Europe, and biogas is Germany's fastest growing renewable energy sector.
One controversial study last year claimed that the EU could produce enough biogas to replace all natural gas imports from Russia by 2020, which would change Europe's energy security outlook considerably if it proves to be correct. The main findings of the study were:
* Europe's potential for the sustainable production of biomethane is 500 billion cubic meters of natural gas equivalent (17.7 trillion cubic feet) per year. This is roughly the total amount of natural gas currently consumed by the entire European Union.
* The entire EU's natural gas needs for the the medium-term future (2020) can be met by biogas; all imports from Russia can be replaced, while the excess can substitute petroleum and coal.
* The production of 500 billion cubic meters of biogas, fed into the grid, will result in a reduction of 15% of Europe's CO2 emissions. The Kyoto protocol demands a reduction of 10%.
* An efficient biogas-feed-in strategy will be build around the concept of 'biogas corridors': such corridors consist of biomass plantations established alongside the pipelines, so that the green gas can be fed into Europe's main natural gas grid without the need for new pipelines and infrastructures.
* A Europe-wide biogas-feed-in strategy will result in the creation of 2.7 million new jobs within the EU. Employment will be generated mainly in agriculture, in the manufacture, construction and management of biogas plants and biogas purification plants.
These sorts of plans will raise the usual questions about the wisdom of "fermenting the food supply" and the like, so at this point it is worth taking the claims in this report with a grain of salt.
One company leading the way in Germany is Schmack Biogas, who are piloting feeding biogas into the grid and claim their super maize crop "reduces the land needed to grow feedstock by up to a third" and "restore degraded land and increase its fertility" - all of which sounds very nice, if true.
A related venture is the Combined power Plant idea being promoted by the University of Kassel, Enercon, SolarWorld and Schmack. This proposed plant "links and controls 36 wind, solar, biomass and hydropower installations spread throughout German", making it the distributed equivalent of a large conventional power plant. The plant uses biogas and hydro power to even out supply when the wind and solar components are generating at reduced capacity.
This is yet another TOD post on a useless techno-fix. I have been thinking that TOD should be renamed TSP, The Solar Panel, but maybe TPP is better, The Poo Power. When is TOD going to face up to Peak Oil and examine contingency planning and how to save lives in the Peak Oil crisis that is coming soon? Banana Power and Poo Power are not going to save lives. How much oil, natural gas, and coal is going to be used in mining metals, developing, manufacturing, transporting, and maintaining these bio-technic fixes, and what food will NOT be grown in wasting good natural fertilizer (bananas and poo)? Everyone who works in the thousands of jobs in mining metals, developing, manufacturing, transporting, and maintaining these bio-technic fixes will be use gasoline to drive to work, and all of the factories will use electricity and many will use oil or natural gas for heating. And pipelines (which consume oil, natural gas, or oil in their manufacture and transportation) or diesel consuming trucks will be used to transport the gas made from bananas and poo.
Hmmm - you didn't seem to read the post.
If you do believe collapse is inevitable, aren't those Indian single-home biodigesters kind of useful things ? No oil or anything else required.
How about banana farms that can power their vehicles using the gas they produce - and the local town ?
With the same applying for pig farms, and cattle farms etc ?
How about the Swedes powering their public transport systems using biogas from wastewater and sewage plants ?
How about German's supplying some (or maybe all) of their natural gas needs with biogas ?
I would have thought these were positive developments worth considering.
Oil isn't the only energy source - there are a myriad of other options.
I think its worthwhile considering all of them.
The German's have done much that is not worth emulating, and this is one of them. You have not responded to my questions concerning how much energy is used in developing this gas infrastructure (how many millions of Indian houses for the biodigesters and how much piping and energy that goes into it)? Nor did you respond to the questions regarding the trade off between gas production and fertilizer; this is not only important in nations like India and China, but in the so-called developed world, where soil depletion means that when we run out of chemical fertilizer, we are in a world of starvation. Gas production from agricultural "waste" means reduced food production. Moreover, the farm animal economy is wasteful of grain. Raising animals for food wastes much grain, as animals expel much energy in body heat and the elimination of methane gases. In the last few days I have been talking with an old man who was about to sell me his 100 acre/40 hectare little ranch in the state of Veracruz, Mexico. He and few people working with him have never had electricity or telephone. They do everything by hand, and all of the animal waste goes back into agricultural production. I realized, that farm and home life is possible without electricity. I have never seen a happier person in all my life! The quest for more energy is the problem, not the solution. Some gas production methods may make sense, like using the gas from land waste fills and probably sewage for heating. In that case, I'm sure that in that case the gas obtained was not taken from agriculture and the EROEI is positive.
The sooner you stop using Electricity, the sooner you'll be happily rid of TOD, and this silly insistence on there being SOME forms of energy generation out there.. you seem to think that None At All is the best amount, in which case, walk your talk already.
If you object to this imagined mass of wasted production energy used to build a reasonably simple system, then bring some numbers or articles and make a CASE. Gav doesn't have to support your argument for you.
In the article I linked below as well, http://journeytoforever.org/biofuel_library/methane_pain.html the author and Mssr Pain explained that the used slurry was then applied as mulching to their soil, which had previously been poor for growing.. so it hardly seems like they're compromising their growing capacity by producing cooking, lighting and driving gas beforehand.
" Once fermentation ends, the big, magic cake produces no more energy, but it will still render 50 tons of natural fertilizer. By spreading a layer of this humus on the poor, stony soil around the house, Jean Pain has created a luxurious farm garden where even tropical vegetables grow. I admire tomato plants two-and-a-half metres high, lift a six-kilo watermelon and inspect a chayote (a kind of sweet Zucchini -- hitherto found only in the West Indies and in Africa), What surprises me most is that these giant vegetables need no watering; all the water they require, Pain tells me, is synthesized in the compost."
Bob
If one is peddling poo as a viable energy solution, he or she must bring the figures to show that is environmentally sound and provides more energy than it uses.
Shit is a renewable resource. People and animals continue to create a lot of shit whether we put it in biogas digesters or not.
I'm not sure why you imagine that shit put into a biogas digester takes more energy to produce than shit which is flushed down the loo. Do you feel an energy deficit after going to the toilet?
The stuff is going to decay and produce some methane anyway, whether we bury it, put it through a sewage settling system, chuck it in the sea, or whatever.
In nature animals eat plants, the digested plants are turned into manure and urine which gets dropped onto the soil, the manure and urine break down and gives nutrients to the plants, it's a cycle. Humans currently break this cycle by removing their manure from the system and putting it through machines, because we're paranoid about disease.
The machines we put our excrement through already produce a lot of methane. The only question is whether we bother using that methane or we just discharge it into the atmosphere. Since it's 23 times as strong a greenhouse gas as the carbon dioxide it'd turn into if we burned it, it seems better to use it.
Of course, ideally we keep the sludge afterwards to be fertiliser. As this paper notes,
In fact the faeces and urine per person varies according to diet. Urine is about 500lt annually on average, and faeces 36-100kg annually; vegetarian diets give higher volume. The faeces are useful as a soil conditioner, and the urine for its nutrients (the traditional nitrogen, phosphorous and potassium of artificial fertilisers).
Maybe we could just hook cj up to a bio-gas digestor. Hes seems to be full of it. ;)
This says more about you, than me. Personal attacks rather dealing with the issues.
Thanks - that was one of my main points - this methane is getting produced and we might as well make use of it - in some cases we'll actually be cleaning up festering and polluting eyesores (aka the burning poo mountains).
The fact that we end up producing less total greenhouse gas (in terms of effect) is just another bonus.
On a semi-related note, given the scatological bent of this thread, here's a post from WorldChanging which includes a DIY home fertiliser manufacturing kit - you pass your urine through it and voila - happy house plants...
http://www.worldchanging.com/archives/007883.html
It is important to reduce the volume poo generated in the world, as it wastes the energy in food (from body heat and methane generation), and much of food comes from natural gas/fertilizer, so poo wastes natural gas and also oil that was used to plant and harvest. In short, animals are very wasteful of energy in comparison to growing vegetables and grain. When there is poo, get it into the ground as fast as possible to reduce the generation of methane, or dry it as fast as possible to reduce the generation of methane. And don't give others a lot of #$%@.
CJ, very few on this board would argue that industrialized meat industry isn't oversized and way out of balance, not the least because of the degrading quality of food that we end up with, as well as the inputs, the pharma Hormone and Antibiotic components, as well as the mountainous wastes at the other end. It doesn't change the fact that we raise all sorts of animals, and will continue to do so. We raise chickens, pigs, cows, horses, oxen, rabbits, Bison, Ostriches, Sheep, Goats, Turkeys etc, etc. Even if the industrial scaling of these operations is brought back into balance, the fact will remain that we have all sorts of waste matter from both humans and animals, and we can use it BOTH as Fertilizer and for Digesting the Methane for other energy needs. Beyond that is the use of probably much MORE scrap material from plant sources, and which again, is NOT pulled from the growing cycle, as it is returned to the fields as compost later on.
Bob
Having fairly large operations such as 500 dairy cows gives a rational biogas plant and a small cluster of such would be good for an economical gas treatment plant to get the biogas up to wehicle gas specification.
A central purpose of TOD should be to advise people to do wise things regarding food and energy, like reducing the use of animals for food and dairy products. So, I suggest we do that, rather than advise people to keep on wasting energy by raising animals and then implement another techno-fix that wastes energy and fertilizer.
I would rather eat more mostly grass fed beef that during the summer grazed land that has been grazed for more then a thousand years.
CJ!!!
You are not wasting the fertilizer! Just take the 'Jean Pain' example, if you still want to ignore ALL the other ones posted here, and show me how the fertilizer was wasted. If you cannot, then stop saying that. Are you seven? what is up with you?
You are capturing energy that is OTHERWISE wasted!
Alright, other readers are probably fed up with my trying to communicate with you.
You have nothing to say.
Well - I'd like to commend you for your persistence - sometimes when people dogmatically insist on something, no matter how wrong, it does end up influencing those reading.
But hopefully your point has been made now.
.. and hopefully the point was right, too.
I'm happy to get rebuttals, that's how I can learn here.
Thanks,
Bob
Your comments indicate a negative bias toward me. If you can't comport yourself in a more professional fashion you should resign your position at TOD.
Mate, you're on the internet. Complete stranger, words on a screen. Get up from your chair, walk around outside for a bit, have a cup of coffee, relax. Return refreshed and with perspective. Or you could just remember to take your Hard Pills (TM) in the morning.
If you are talking to me then I would like to point out that you have been completely disrespectful to me (and TOD) since this thread started and you have made one incorrect statement after another.
If your accuracy and your manners improve I may start to show you some respect in return.
This isn't "bias" - its a simple case of being treated the way you treat others. Get over it.
Also, after crap has gone through a digester the sludge that remains is pretty mineral rich. In some cases it makes a good fertilizer (although you have to watch the salt level as you do with manure) on its own or is easy to process into a good fertilizer.
On the contrary, I have much to say. Please stop your personal attacks in saying "You have nothing to say." I have not ignored ALL of the other biogas projects, as you say. I was a professor of political science at the University of New Hampshire (UNH) until January 2008, and I am well informed about the use of natural gas from a not-so-local land fill, and I commented so on this post today. Even in this case I have doubts about what was accomplished. A pipe line was constructed from Rochester, NH to Durham, NH. That is laying some 20 miles of pipe. The natural gas, oil, and coal used to make 20 miles of pipe and transport it many miles from where it was made is significant, and the diesel used in digging and the gasoline in transportation is significant. Add to that all of the people who were employed in making the pipe, transporting it, making the equipment that dug deep trenches and channeled the pipe under the Cocheco River -- all of those employees who make a salary and will spend it and thus use more oil. The companies where the stuff is manufactured use oil and natural gas to heat factories and offices, and they all use electricity. Imagine how many hundreds of people are involved in the companies that make pipe and dig and move land -- land moving trucks, pick up trucks, back loaders, back hoes, etc. Think of all of the people commuting to all of these jobs. Think of all of the administrative and clerical personnel in all of these companies, and all of the profits that will go to stockholders. And the salaries and profits will go on car or air travel vacations, trips to the mall or whatever. The digging, welding, architectural firms, etc. And all of the time spent on this means time is not spent on other projects that could save energy. When I was chair of the Energy Policy Committee at UNH, the head of the energy office and I estimated that we could save a million dollars per year just by implementing a program to get students and faculty to shut windows in classrooms at the end of night classes. It is common to walk by big classroom buildings with most of the windows open ALL NIGHT LONG when it is 10 degrees outside -- just pouring out the heat from #6 fuel oil into the air. The administration ignored our plans, they probably were not sexy enough and they would have to work at it on a regular basis. The million dollars a year in 1985 is probably 5 million today. That is a lot of #6 oil over 22 years ... that is a lot of oil. So now they have a natural gas project that is very sexy (and their careers will be advanced), but will it save much energy, I doubt it. No one knows how many years the land fill will generate gas, I doubt many years. They could save a lot more energy by educating students, faculty and administrators about the need to close windows, but that wouldn't be sexy. Good grief!
It is best to quit fooling around with trying to control nature. We've can't win that battle. Most of these techno-fixes are wasting energy, not conserving it. The problem is the continued quest to use more energy from fossil fuels (most farm waste gets its energy originally from fertilizer/natural gas). Quit using a lot of energy in making pipe and equipment and quit wasting energy on farm waste and instead put it into the ground where it will do some good, but it isn't very sexy.
Well Clif, you've finally said something new. I'm sorry I said you had nothing to say, but from the last several DOZEN posts, that was the only conclusion I could come to. And with your final conclusion to this one, I probably won't take this much further. How many times have people said that the effluent FROM many of these systems went back INTO THE GROUND as fertilizer?! If you can say it's not good fertilizer, then say it. But giving jobs to people laying pipe, making pipe, mining metals for pipe? If it's a durable system to carry a completely renewable energy supply, then why is that not a healthy investment?
The above was a Good story, and I'm sorry to hear that UNH was unwilling to work on some of the most basic efficiency measures. Their loss and ours. I'm going over to USM (Southern Maine) This morning for a symposium "Preparing Our Region for a Sustainable Energy Future".. they have an Energy Efficiency and Renewables/Sustainability program led by Dudley Greeley which has made a lot of noise and impact in the College Community there. They do use PV and Solar Hot Water Collectors, but this is not the beginning or the end of their effort. Basic, personal habits, reduction of waste everywhere Dudley could find it has made him respected and frequently just barely tolerated in his zealousness there, but he has managed to get the program going very well, and has served USM in many ways.
Your objections still aren't making your point. This pipeline in NH might have been a huge waste, who knows? Make that the story and show us how.. but to lump it together with the whole category, where example after example have shown modest infrastructure and clear benefits .. you come off as a crank, unwilling to hear the idea that there is a balancing point, and ways to apply this with reasonable inputs and get useful returns.
Bob
That's right, the central purpose of TOD is to promote vegetarianism, rather than energy solutions.
Yes indeed, and as cjwirth has just shown, people can of course *talk* this valuable substance as well ...
You requested figures. I'll supply them.
The graphic above, reflects the average daily methane generation for each month of at a 500 sow, 50 boar farrow-to-finish pig farm using a covered earthen basin anaerobic pond digester. The gas is collected from the head space above the water level. The barns utilize a low solids flush system. The holding times represents the difference in methane generation from different residence times in the pond (initially accomplished by sectioning the pond and partial coverage of the surface). Nominally there are ~12,000 pigs on this farm at various growing stages throughout the year. This is a real and operating system.
The digester operates in the mesophillic range and is allowed to temperature drift with ambient/seasonal conditions. The system is also equipped to be heated with the waste heat from the IC engine that drives a generator to "flatten" the curve to around 35,000 cu feet/day or to drive it into the thermophillic range where the gas production is approximately 20% greater. But that is an either/or proposition. You operate in one regime or the other because your gas production falls off dramatically when you are trapped between the mesophillic and thermophillic range. Alternatively, the waste heat can be used to heat the barns and onsite greenhouses directly.
As a state, we nominally handle between 32 and 37 million pigs per year, though approximately half of the pigs that are farrowed here end up in some other state. But our nominal pig count (the way the USDA does the inventory) is about 10 million pigs...but the way to calculate the potential methane accurately is by steady-state live weight since you have to consider the farm type (e.g., farrow to wean, farrow to feeder, farrow to finish, wean to finish, feeder to finish, etc.).
Please stop peddling your pig poo here. It is very stinky stuff. It is important to reduce the volume poo generated in the world, as it wastes the energy in food (from body heat and methane generation), and much of food comes from using natural gas/fertilizer, so poo wastes natural gas and also oil that was used to plant and harvest. In short, animals are very wasteful of energy in comparison to growing vegetables and grain. When there is poo, get it into the ground as fast as possible to reduce the generation of methane, or dry it as fast as possible to reduce the generation of methane.
Request denied. You stated that people should be produce figures to back up their argument and when someone does (and there are people here that have far more expertise than you profess to have in your bio), you further dig yourself into a hole. So, you just made a bunch of claims inyour reply...let's see you back them up with data.
Otherwise,
Stop peddling YOUR poo here.
It is important to reduce the volume of YOUR poo generated in the world, as it wastes the energy in food, and much of food comes from using natural gas/fertilizer, so YOUR poo wastes natural gas and also oil that was used to plant and harvest. In short, YOU are very wasteful of energy.
Unless you are able to demonstrate that you physically and personally produced more of the following either singly or in combination in equivalent energy production, you have an EROEI of less than 1 and by your metrics are deemed wasteful:
3,222 gallons of distillate oil (#2 ULSD),or
3,687 gallons of gasoline, or
3,349 gallons of kerosene, or
598 cubic feet of pure methane, or
14.63 tons of bituminous coal w/ HHV of 12,010 BTU/lb, or
19.41 tons of subbituminous coal w/ HHV of 8,735 BTU/lb, or
a nominal 34,500 kWh net electrical energy ouput
If you cannot meet these minimum standards for an EROEI you should, therfore, apply the appropriate remedy to yourself.
Thanks for providing the numbers earlier - I'll give CJ one thing - his constant insistence that all energy sources are bad does prompt people to come forward with additional information - which is what I love about TOD.
Makes me wonder how he powers his computer, or why he's online at all.
Just as I suggest that the people who think population is a problem should prove the strength of their convictions by topping themselves, so too do I think those who are against modern civilisation should get offline.
I don't insist that all energy sources are bad, rather I promote conserving fossil energy, rather than wasting them. And, as you well know, I have regularly commented on the utility of passive solar and have asked for more posts on passive solar, but you continue to post techno-fixes. Your comments indicate a negative bias toward me. If you can't comport yourself in a more professional fashion you should resign your position at TOD.
@cjwirth
One of the great things about TOD is that if you have something to say, they will post it for you. If you want more posts on passive solar, why dont you write it and I'm sure they'll put it up.
Passive solar is also a technolgy issue. You have to build something to catch the energy which is to a degree a techno fix. The best passive solar uses modern building material of concrete, glass steel, and insulation materials.
I get quite frustrated by Luddite purists who lump all technolgy together as unsustainable. We are not going to lose the all the knowledge gained from the oil fossil fuel age and much of what we have learned will find new applications in the post peak future.
Securing and preserving that knowledge is essential for the future as we will not be able to dedicate spare resources for pure research in any area.
If you want to dismiss all knowledge of technology just because it won't scale to power BAU, then you miss the point of why we here - to learn from eachother, prepare ourselves and hopefully be able to emerge from the post peak turmoil relatively unscathed.
I see you a re political scientist so I would like to see you post on your area of expertise. My challenge is for you to write a post about what action we need to take to prevent World War in the not too distant futre as the oil supply declines.
You are welcome. This is an operating system.
It's intersting that my senior ChE project was anaerobic digestion of swine waste using solar power as the energy source to maintain and operate the digester in the desired temperature range. never thought that something I did more than 30 years ago would be relevant to what I work on today.
So you'd like us all to hold it in?
I think Freud would have something to say about your ideas.