Solar Power isn't Feasible!

Solar Power isn't Feasible!
This cartoon was on the cover of the book "SolarGas" by David Hoye. It echoes the Sharp Solar slogan "Last time I checked nobody owned the sun!"

Wednesday, September 8, 2010

Cleaning Nigeria using everything AND the kitchen sink!

(Photo:The students of Bell's High School do the "Frontline SMS" logo cheer in front of their completed kitchen waste biogas digestor to share with National Geographic Emerging Explorer colleague Ken Banks, whose Frontline SMS technology is being used by Solar CITIES to help biogas users across Africa share results and innovations and troubleshoot their systems.)




A tale of two Insinkerators

Abstract:
At the end of August, 2010, Solar CITIES delivered two Insinkerators, donated to our cause by Emerson Electronics and the Insinkerator corporation, to their new homes in Nigeria.

One we placed in the kitchen sink of the visionary former Nigerian President Olusegun Obasanjo, who has been championing green technology and reforestation in his country and throughout Africa, and the other was given to Naijatomo Holistic Waste Management Company founder Balogun Olowusegun, who has dedicated his company to helping solve Nigeria's solid waste problem (Naijatomo means "clean nigeria").

These Insinkerator appliances were connected to home-scale kitchen-waste-to-cooking-fuel-and-fertilizer biogas systems so that all organic wastes now are used to produce useful products rather than ending up in plastic bags clogging the sewers and causing floods and health hazards.

From these small seeds we expect a new green revolution to sprout; the end result of our trip to Nigeria was President Obasanjo's announcement of the creation with us and regional experts of Africa's first "Green Economy Center", to be housed at the Presidential Library and Museum, which will work to disseminate appropriately scaled clean energy, water and waste-recycling technologies throughout Africa.

We see the Insinkerator being a key upstream component that will allow every household to participate in meaningful solutions to Africa's environmental challenges as well as to the downstream issue of mitigating climate change.

Ironically, we finished installing the Insinkerator and Nigeria's first household scale kitchen-waste-to-biogas system on August 27th, 2010, and we learned from watching a Nigerian television news report that night with His Excellency that exactly 151 years earlier, on August 27th 1859, "oil was discovered in Titusville, Pennsylvania, leading to the birth of the oil age".

President Obasanjo, who has just finished building Nigeria's first large scale biogas system (2500 scm per day from corn processing wastes with Indian biofuels expert K.S. Rao at the Obasanjo factory "Temp Starch and Glucose Limited") felt it appropriate that his nation, which has received both blessings and curses because of the oil age, become Africa's leader in clean, distributed generation, renewable energy, starting with kitchen and food processing wastes. The Insinkerator technology, which is available in domestic and industrial sizes, is seen as the first step in the scale up to an efficient "biofuel" age in Africa.


(Photo: H.E. President Obasanjo's commercial biogas reactor, built by Indian technical engineer K.S. Rao at the Temp Starch and Glucose Factory on Quarry Road in Abeokuta. Right is the digestor tank, connected via moisture traps in the piping to the factory. Left is the temporary gas storage and pressure vessel (telescoping design). Mid-picture you can see the small lube compressor that pressurizes the gas up to 3 bar for delivery to the factory boilers. The 2500 scm of biogas produced here provides 1/6th of the fuel requirements for the factory. Obasanjo is leading the country toward a clean renewable energy fueled future.)



Solar CITIES would like to thank David McNair, Kendall Christiansen, Craig Sumner, William Chris Kostman Virginia Busch and the entire Insinkerator/Emerson Electronics team for their vision, their support and help, and their belief in our Middle East/Africa mission.


(Left to right: T.H. Culhane, Mrs. Obasanjo, His Excellency President Obasanjo, Paul Chido Iwunna, Dr. Charisma Acey. Photos courtesy of Dr. Charisma Acey.)





Left to right: Dr. Moses Oyatogun, Chief Iyke, Diamond Technical Corporation, T.H. Culhane, Paul Chido Iwunna and, smiling as T.H. presents Balogun Olowusegun and Naijatomo with an Insinkerator to aid in their development of clean energy and waste management solutions for all Nigeria.



During the last week of August, 2010, Solar CITIES founder Dr. T.H. Culhane, and team and board members Paul Chido Iwunna and Dr. Charisma Acey presented His Excellency President Olusegun Obasanjo and his wife with an Insinkerator "food-waste-to-fuel-feedstock" appliance to use with the home-scale "kitchen-waste-to-biogas" digestor that we built just outside the former Nigerian leader's kitchen.

The Insinkerator unit was a gift from St. Louis, Missouri based Emerson Electronics and their Milwaukee, Wisconson based Insinkerator division.





Outside the kitchen, Obasanjo's chief engineer, Jerry, demonstrated the installation of the Insinkerator to the staff and to visitors and guests before putting the new large-diameter sink, purchased especially to fit the new appliance, into the kitchen for daily use.









Now equipped with its food-waste-to-fuel-feedstock unit, all the organic wastes flow immediately into the below ground biogas digestor that Culhane and his team built with the Obasanjo staff.





Dr. Moses Oyatogun of the Department of Forestry and Wildlife Management, College of Environmental Resources Management at the Abeokuta University of Agriculture explained to the former President and the crowd why he believes that Insinkerators can have a major impact all over Nigeria and the African continent (contact him at moyatogun2k@yahoo.com).





"The basic idea", Dr. Oyatogun explained, "is that food scraps contain an enormous amount of energy and all the micronutrients needed to keep the local ecology healthy, yet ironically we throw these riches away and we do so in such a way that we actually create major health problems. The Insinkerator, as a first line of ecological defense, makes it not only possible, but actually convenient for every family and household to participate in Nigeria's improvement."



His Excellency Obasanjo, himself a farmer with decades of experience in improved agro-ecology, spoke passionately about Nigeria's need to realize the benefits that can be captured from the waste streams of homes, farms and industries, and suggested that organic waste grinding technologies could be used at many different scales.





T.H. and His Excellency shared a handshake over their agreement and their conviction that food waste grinders like the Insinkerator have the potential to play a major role in helping to produce clean energy, stop deforestation and clean the streets and natural environments throughout Africa, while providing valuable fertilizer to keep the Green Revolution going, all the while providing multiple micro-economic opportunities.



Outside the Obasanjo home, led by Nigeria's first democratically elected two-term President, everyone took turns throwing various common food wastes into the Insinkerator in a dedication ceremony just before the sink was installed inside the kitchen, connected to the pipes leading to the biodigestor and commissioned.


Former Nigerian President Olusegun Obasanjo (center) drops scraps from his kitchen into his new insinkerator, a gift from Solar CITIES and Emerson Electronics/Insinkerator Corporation, at a press ceremony where he explained how food wastes in Nigeria will now go from being a problem to being a solution for a healthier, cleaner and more secure Africa.



Solar CITIES was also encouraged by His Excellency to invite Balogun Olowusegun and Immanuelle Thonda from the visionary and holistic waste management and recycling company "Naijatomo" (Clean Nigeria) to the former President's home, as well Chief Iyke from the Lagos-based Nigerian Insinkerator sales and service company Diamond Technical Corporation (contact insink2004@yahoo.co.in).





T.H., Paul and Charisma of Solar CITIES and the US based Emerson Electronics/Insinkerator Corporation present an Insinkerator as a gift to Naijatomo founders Balogun Oluwasegun (red shirt) and Immanuelle Thonda (far left) as Dr. Moses Oyatogun, director of the new Green Economy Center (Green outfit) and Chief Iyke of Diamond Technical Corporation, the Nigerian Insinkerator dealers (white shirt) share the celebration.

At the end of the day, Solar CITIES presented a second Insinkerator as a gift to Naijatomo so that they could incorporate it into their waste management system. This unit was also a gift from Emerson Electronics and Insinkerator corporation to the Solar CITIES Middle-East/Africa clean energy initiative.




A few days later Chief Ike and Dr. Moses returned to look at how the Insinkerator, now installed in the Obasanjo kitchen, connects to the home-scale biodigestor that Solar CITIES built just outside the kitchen door, discussing its benefits with Mrs. Obasanjo, who particularly wants to see these solutions implemented in such a way that they benefit women and children, who bear most of the burdens of cooking, water fetching and waste disposal.



Culhane showed Chief Iyke and guests and visitors how the Insinkerator's output can be output with a valve either directly to the common drain, or diverted to the biogas digestor, located below ground for automatic gravity feeding of the Insinkerator slurry.



Back inside the dining room, President Obasanjo called a meeting to officially launch the "Green Economy Center for Research and Development", to be housed at his new Presidential Library and Museum where all types of Environmentally sustainable technologies will be showcased so that Nigerians and other Africans, as well as visitors from all Nations, can gain firsthand experience with green solutions to ecological and economic challenges.




Solar CITIES was appointed by His Excellency to be international advisers and coordinators to the Green Economy Center, which will be registered as an NGO and housed at the Presidential Library. Dr. Moses Oyatogun, from the College of Environmental Resources Management in Abeokuta (moyatogun2k@yahoo.com) was appointed the director of the new center, and Naijatomo and Diamond Technical Company, as holistic waste management and Insinkerator-representatives and environmental consultants, were appointed to be business partners/sponsors of the NGO.

We conceive of the Insinkerator as a pivotal game changing technology that is the centerpiece of our home-scale solutions package for waste, water and energy problems.

Dr. Iyke, who has been importing, selling, installing and repairing Insinkerators since 2004, explained some of the reasons that these marvelous devices have not yet become popular in Nigeria and the rest of Africa (currently Nigeria is the only country to have a company representing the Insinkerator product line.) Among the reasons were:

1) Lack of building codes or standards that would make installation easy and inexpensive.
Currently neither the sink flanges, heights and dimensions, nor the normal piping used in Nigeria make installation of an Insinkerator a plug and play operation like it is in the U.S. Diamond Technical Company is working with the Abuja Environmental Board and has authored a bill to go before the government calling for standards that will make putting in an Insinkerator as easy as putting in a toilet (an area where there are plumbing standards in the housing code).

2) A very high import tariff (45%) that drastically increases the retail price of the Insinkerators so that they are out of reach for most consumers. Government needs to see these appliances as a net benefit to Nigeria on many levels and remove barriers to free trade. If the terms of trade were favourable to Nigerian companies to bring them in by sea to Lagos and sell them near the true market price, Insinkerator sales from Nigeria could open up the entire African continent market, benefiting both the US and the Nigerian economies .

3) High air transportation costs because of low volume importing of the units (which weigh between 7.5 and 15 kg).
Chief Iyke lamented that there is little investment confidence in Nigeria and that it is difficult to get foreign companies to extend a credit line or ship a large quantity of units in bulk on consignment. He said that if wholesale distributors in the U.S. would develop a relationship of trust with his company and others in Nigeria and give them the same business advantages that other countries get, the Nigerian market demand would drive a very good business. Sea transport of containers with Insinkerators would bring the costs down to the point that he could offer units near the US price. Currently Diamond Technical Corp flies in small orders of units.

The prices in Nigeria, distorted by the 45% clearance tax, are currently as follows (installation costs 5,000 Naira, equivalent to $33):

Badger (0.5 HP): 49,000 Naira ( = $ 326, as compared to $89 at Home Depot in the US). Chief Iyke noted that if he got volume shipments he could cut the price in half, to 25,000 Naira ($166).

Model 55: (.55HP) 55,000 Naira (= $366)
Model 65: (.65HP) 65,000 Naira (= $433)
Model 75 (.75HP): 75,000 Naira (= $500)
Model Evolution (.75 HP): 85,000 Naira (= $566)

At these prices, roughly 365% more than the US cost, and especially relative to the Nigerian economy, Insinkerators are out of reach for all but the wealthiest in the country. Even among the wealthy they are considered a low priority luxury. For this reason we chose to install Model 55 units into both the former President's kitchen and that of Naijatomo, since this model is closer to what the consumer market may be able to afford in the near future. The Evolution models, while much more efficient, flexible in terms of feedstock (able to grind even bones, corn cobs, seeds and pits) and quiet, are out of the price range considered tolerable in the Nigerian market until volume imports create transportation economies of sacle and the clearance tax is reduced or removed. The former President's aim in having an Insinkerator and a biogas digestor in his own home is to show his commitment to what he hopes with be a popular everyman/everywoman solution to the energy and waste problems plaguing his country, so he chose to have models of these technologies that were affordable and appropriate.

One thing President Obasanjo discussed was looking into the possibility of licensing to manufacture in Nigeria itself, so that key high quality parts and essential motor control technologies could be brought into the country and assembly of the final product could be done in country. This form of quasi-import substitution would radically reduce costs until they approached US levels. The advantage would be huge volume sales (Nigeria is Africa's most populous nation whose approximately 150 million people make up 1/6th of Africa's total population) and market leadership for Insinkerator throughout the continent (the current market competitor in Nigeria is South Africa's "Sinkmaster" product line, but Chief Iyke says, "Their concept for environmental management in Africa is good, but they don't last. Insinkerator uses quality parts, and that is what we need to build consumer confidence in this unique waste disposal solution.")

Chief Iyke showed the Insinkerator promotional video to the Obasanjo Green Economy Group and later we had him show it to Dr. Sowole, medical director of the Sacred Heart hospital where we were building another biodigestor that the materially poor could use and learn from. Dr. Sowole loved the concept but commented "I hope we will see black faces in these promotions". Culhane assured them that Insinkerator already had literature in many languages (including Arabic) and Chief Iyke informed the hospital that Diamond Technical Corp had already filmed and was in production of a food disposer video featuring Nigerian talent. The key factors in launching the public awareness campaign would be clean energy, reduced reliance on forest-derived fuels (90% of the deforestation and consequent habitat loss in Nigeria is due to wood being felled for direct fuel or charcoal, with attendant respiratory risks compounding the soil erosion and biodiversity loss threats) and the diminishing of foul plastic bag wastes acting as breeding sites for pathogenic bacteria. The Insinkerator/Biogas solution thus fits into both environmental and public health campaigns.

"What we need now", our colleagues in Nigeria told us , is for the American and European companies to trust us and invest in us as individuals fighting on the same team and help us grow the Insinkerator and household/community/municipal biogas markets; right now many people mistrust Nigeria because of the bad press we get relating to internet scams and such but they shouldn't. Countries can't be bad; individuals can, but our countries are made up of many individuals, good and bad, and we who are working hard on making Nigeria and the world a better place need to work together."


Culhane explains the biology of methanogenesis to the students of Obasanjo's Bell's Secondary School. Solar CITIES believes that women in particular have the right to become stewards of the primary energy, water and waste recycling technologies used in a household since most consumption and production occurs in the kitchens and bathrooms, which are traditionally female domains.
Balogun Olowasegun of Naijatomo Holistic Waste Management company, addresses the teachers and the press, explaining how point-source separation of organic and inorganic wastes (made even more convenient by an Insinkerator) can lead to immediate clean air/water/and land benefits for Nigeria.
Culhane explains to the press that Solar CITIES has built 4 digestors in Abeokuta, one at His Excellency Obasanjo's home, one here at the Bells School, one by the kitchen of University Professor and Green Economy Center director Moses Oyatogun, and one at the Sacred Heart Hospital where all sectors of society can see it functioning. In addition Naijatomo is building one, and two Insinkerators have been installed to effortlessly feed the biodigestors.

Building an ARTI INDIA style Biogas Digestor at Belles Secondary School in Nigeria

Culhane learned how to build ARTI style biodigestors from Dr. Anand Karve in Pune India, and has made simple modifications to suit local conditions and budgets. Here a 2" rather than 4" feedpipe is being installed to keep costs low. The slurry put out by an insinkerator is small enough in particulate sizes to permit smaller and less expensive piping.
This finished above ground 2000 liter biogas reactor outside the school cafeteria is merely in need of an industrial sized Insinkerator to turn all of the schools' wastes into feedstock slurry. In the meantime, students pound the food in water with a large traditional African wooden mortar and pestle.





Solar CITIES and Naijatomo finish the training with the Bell's school science students.



Jimo (Obasanjo staff driving pool), a teacher from the Bell's school, the head plumber/mechanic for the Bell's school, Balogun Oluwasegun from Naijatomo, Dr. T.H. Culhane and Dr. Charisma Acey from Solar CITIES and Emmanuelle Thonde from Naijatomo flank the new teaching digestor at the Bell's school.

The students of Bell's High School do the "Frontline SMS" logo cheer to share with National Geographic Emerging Explorer colleague Ken Banks, whose Frontline SMS technology is being used by Solar CITIES to help biogas users across Africa share results and innovations and troubleshoot their systems.


Dr. Charisma Acey and Dr. T.H. Culhane pose in front of our third of four biodigestors that we trained our colleagues to build in NIgeria; this one is behind the kitchen at the Sacred Heart Hospital in Abeokuta, where all social classes have access to it and can learn from it.

Tuesday, June 22, 2010

Building your "sacred cow" biogas digestor (By Hanna Fathy, Solar CITIES Zabaleen community director)






مقدمه عن المشروع البيوجاذ

من حنا فتحي في حي الزبلين في القاهره

تشكل القمامه في كثير من الاماكن مشكله كبيره و خصوصا مشكله التخلص من المواد العضويه واعاده تدويرها ونتج عن ذلك تراكم المواد العضويه بالشوارع او التخلص منها بالقائها فى اماكن خارج المدينه واحيانا في الماء وهذاما يؤدى الى تلوث التربه والماء و الهواء بالروائح الكريهة والميكروبات نتيجه تعفنها و ايضا تؤدى الى زياده مشكله الاحتباس الحرارى عند تحلل المواد العضويه بالماء اوبالشوارع لاهوائيا فأنها تنتج غاز الميثان وهو ضار بمعدل 28 مره اكثر من ثانى اكسيد الكربون لان نسبه امتصاصه للاشعه تحت الحمراء 15% وايضا توالد وتكاثر الحشرات والفئران وانتشار الامراض والاؤبئه وايضا نقلها للمقالب طريقه مكلفه للنقل و ينتج عنها الغازات المدفئه وان هذه المخلفات هى مصدر اساسى للسماد العضوى و ايضا نظرا لاهميه الكائنات الحيه الدقيقه فى التربه

فكره المشروع

هى استخدام البكتريا اللاهوائيه والتى يتم الحصول عليها بوضع كميه من روث الحيوانات قبل جفافه لضمان عدم موت البكتري بداخل النظام ا وذلك لانها تقوم بتحليل وهضم المواد العضويه كما تفعل داخل معده هذا الحيوان للحصول على غاز المثان والسماد العضوى والتخلص من المواد العضويه بطريقه بيئيه

ولكن فى هذه الطريقه نقوم بفرم مخلفات المطبخ العضويه لتسهيل عمليه تحليها ووضعها للبكتريا من خلال النظام

لان المواد العضويه تحتوى على الطاقه فى صوره كيميائيه وتقوم البكتريا بتحليلها وتكثيرها وانتاج الطاقه الموجودة بها وهذا النظام يختلف عن الطريقه القديمه التى تعتمد فقط على الروث بمعنى ان مخلفات المطبخ تحتوى على الغذاءو الطاقه التى تحتاجها البكتريا افضل من روث الحيوانات لان الروث لايحتوى على اى طاقه لانه مستخدم بالفعل عن طريق الحيوان

من حنا فتحي

مكونات النظام

1برميل اسطوانى 1000 لتر,برميل750 لتر ,2مواسير 3بوصه,1 كوع 3بوصه ومحبي 3بوصه ,نبل خزان 3بوصه,لاصق او غراء PVC,جلبه 3بوصه انثي جلبه 3بوصه ذكر ,نبل خزان 2بوصه,1متر مواسير 2بوصه,1 كوع 2بوصه ,نبل خزان 2/1 بوصه ,كوع حديد 2/1 بوصه محبس 2/1 بوصه ,نبل خرطوم 2/1 بوصه

وصف المشروع

هو عباره عن 2 برميل كما بالشكل

البرميل السفلى حجمه 1000 لتر ويتم عمل 3 فتحات باحجام مختلفه الاولى 3بوصه في الاسفل لتركيب ماسوره اعلى من البرميل بمسافه صغيره وهى لادخال الاكل منها

وايضا فتحه 3بوصه بالاسفل مع محبس ويستخدم فى حال تفريغ النظام او نقله

وفتحه اخرى فى اعلى البرميل بقطر 2بوصه لخروج السائل الزائد عن حجم البرميل

البرمل الثانى خزان الغاز

عباره عن برميل 750 لتر ويتم فتحه من الاعلى وعمل فتحه بقطر 2/1 بوصه فى اسفله ووضع محبس بها وهى لخروج الغاز منها ثم توصل بخرطوم او ماسوره لتوصيل الغاز الى مكان استخدامه

طريقه التشغيل

بعد تجهير البراميل يتم اختبارها والتاكد من عدم التسريب

يتم وضع الروث بالكميه المناسبه للنظام وتكمله البرميل بالماء

وضع البرميل 750 بالمقلوب داخل البرميل الكبير

الانتظار حتى تنشط البكتريا و تنتج غاز ويرتفع البرميل لاعلى بعد حوالي اسبوعين

يتم وضع 1-2 كيلو من زباله المطبخ بعد طحنها ومزجها بكميه معينه من الماء للنظام


ويلاحظ أنه حتى يمكن استخدام مواقد البوتاجاز لتعمل بالبيوجاز لا بد من
إجراء تعديلين، الأول هو توسيع فتحة خروج الغاز (الفونية) للحصول على نفس
كمية الحرارة الناتجة عن الغاز الطبيعي لأن الطاقة الحرارية للبيوجاز أقل
من الغاز الطبيعي، والثاني هو ضرورة تصغير فتحة دخول الهواء لأن كمية
الهواء اللازمة لحرق الغاز حرقا كاملا أقل بالنسبة للبيوجاز عن الغاز
الطبيعي.

ولا تتوقف الفوائد عند هذا الحد، بل له تطبيق آخر لم يتم استخدامه في مصر
وهو إنتاج الطاقة الكهربائية باستخدام مولدات تعمل بالبيوجاز حيث يمكن
للمتر المكعب منه توليد طاقة كهربائية تتراوح من 1.3 إلى 1.5 كيلو وات في
الساعة.

تتخطى مزايا استخدام البيوجاز التخلص من المخلفات التي تعد في حد ذاتها
ميزة لا يستهان بها، بل يتمتع البيوجاز بمزايا متعددة تؤهله لأن يكون
بديلا لمصادر الطاقة العادية
، فهو يستخدم دون معالجات أو تنقية حيث يتخلف عن
احتراقه في المواقد ثاني أكسيد الكربون وبخار الماء، وبالتالي فإنه لا
يسبب تلوثا للهواء الجوي مقارنة بمصادر الطاقة الأخرى حيث ينتج عنها أول
أكسيد الكربون المعروف بتأثيره السام.

والبيوجاز غاز غير سام وعديم اللون وله رائحة الغاز الطبيعي وسرعة اللهب
عند اشتعاله -35 سم في الثانية وهو أبطأ من الغاز الطبيعي- مما يجعله
بديلا أكثر أمنا منه، وتتراوح الطاقة الحرارية الناتجة عنه ما بين 5000
إلى 6000 كيلو كالوري للمتر المكعب.. وقد أثبتت التطبيقات العملية أن

المتر المكعب منه يمكن أن يغطي الاحتياجات الآتية

تشغيل موقد متوسط لمدة من 2.5 إلى 3 ساعات.

تشغيل كلوب برتينة قوة 100 شمعة لمدة من 8 إلى 10 ساعات.

تشغيل آلة احتراق داخلي قدرتها 1 حصان لمدة ساعتين.

تشغيل جرار زراعي زنة 3 طن مسافة 2.8 كجم.

تشغيل فرن متوسط الحجم لمدة ساعتين.

تشغيل دفاية مزارع دواجن طولها 60 سم لمدة ساعتين



Introduction to the Zabaleen Biogas Project

Arabic by Hanna Fathy, Solar CITIES director in the Zabaleen Garbage Recycling Community of Cairo Egypt (English translated and interpreted by T.H. Culhane, Solar CITIES co-founder)

Garbage and litter creates serious problems in many places; an especially big problem is the disposal of organic materials which unfortunately are usually not recycled. This results in the accumulation of organic waste on the streets and/or the dumping of these wastes in places outside the city, often in canals, streams, rivers, lakes and oceans. They are also frequently burned. All of this leads to serious contamination of soil, water and air. The lack of efficient recycling of organic wastes creates more than just unpleasant odors and the potential for disease; microbes in the rotting food actually increase the problem of global warming when the decomposition of organic material proceeds anaerobically (as happens in landfills or garbage bins). These microbes produce methane, a gas that, if not burned, is 28 times more powerful than carbon dioxide. It's rate of absorption of infrared wavelengths is 15% greater than that of CO2. In addition to the global environmental impact and the local environmental impact (particularly the breeding of insects and rats and the transmission of diseases), transfer to landfills is an expensive and inefficient way to deal with these wastes. Not only does trucking them to dumpsites and burying them require a considerable amount of fossil fuels, but the resources themselves are wasted -- resources that could be used to actually reduce the amount of fossil fuels we use. Under controlled conditions of anaerobic decomposition, the methane produced can actually be better used for heating or generating electricity and the wastes themselves are a major source of organic fertilizer and provide important micro-organisms to enrich the soil.

Premise of the Project

Our idea is to use anaerobic bacteria to solve urban waste problems at the household level. The bacteria, which are obtained by placing a small quantity of animal dung before it dries into an airtight container (to ensure a viable bacterial population) are used to digest household kitchen wastes on-site so that families no longer have any organic garbage to throw out. This ensures that the streets remain clean and there is nothing that must go to the landfill (everything else, once clean of organic material, can be easily recycled). Anaerobic bacteria that normally live in an animal's digestive system, called "methanogens", once cultured to a suitable concentration outside the animal, will break down and digest organic materials (like spoiled food) in an "artificial stomach" (a plastic container) just as they do within the stomach of the animal and they will produce easily captured and controlled methane (natural gas) and fertilizer and assist in the disposal of organic material in a safe environmental manner.

Food waste feedstock rather than animal manure

We use organic kitchen waste to feed the anaerobic bacteria not only because it solves the problem of urban organic waste (providing an even richer fertilizer than normal aerobic compost) but leads to two different end products -- a rich liquid fertilizer that is easy to bottle and use (or even sell!) and up to two hours of biogas for household cooking almost every day.

Because the organic materials in kitchen garbage contain an enormous amount of energy in the form of rich chemical bonds, the production of biogas from this feedstock, as Dr. Anand Karve has proven at the Appropriate Rural Technology Institute in Pune India, is up to 400 times more efficient than production from animal waste, wherein the food has already passed through the digestive tract of the animal and is thus a "spent fuel". The ARTI system, which we have replicated in Cairo is thus different from the old and traditional biogas method, which depends only on animal dung as a feedstock. We use animal dung only as a "starter kit" on the first day of construction to create our bacterial culture. Once we have assembled the system (which can take as little as two or three hours) we don't need animal dung again (in a community of biogas producers a new system can be started by using the liquid effluent from somebody else's system, just as people share yoghurt and sourdough bacterial cultures).

System Components

1 cylindrical barrel of 1000 liters, 1 cylindrical barrel of 750 liters, 2 meters of 3 inch diameter tube, 1 T 3-inch diameter, 1 tank adapter 3 inches, one 3 inch valve, teflon tape, PVC glue , two 3 inch female connectors, two 3 inch male connectors; one 1 inch tank adapter, 1 meter of 1 inch tube, 1 Elbow 1 inch, one 1/2 inch tank adaptor, one 1/2 inch elbow, one 1/2 valve, one 1/2 inch brass hose adapter, 25 meters of clear flexible 1/2 inch plastic tubing.

Project Description: "The Sacred Cow"

You are basically trying to create an artificial cow to be the home of your methanogenic bacteria. You need to give your sacred cow a mouth, a throat, an esophagus, and a stomach, as well as a ureter, intestines, a farting bowel and an anus. From the ureter you will get fertilizer; from the anus you will get biogas. Your blender or insinkerator garbage disposal unit will act as the cows teeth for grinding up food.

The cow's stomach:

Cut the top off of the 1000 liter barrel so that 750 liter barrel can fit inside it upside down with about 1/2 inch to spare. This tank becomes what we call our artificial "cow's stomach".

The cow's mouth, throat and esophagus:

At the bottom of the 1000 liter barrel drill a hole (you can burn one through with a hot section of 3" steel pipe if you don't have a drill) to fit the 3" tank adapter. On the inside connect the female connector and connect it with a piece of 3" pipe leading to the center of the tank. On the outside connect the T and connect to this the drainage valve and a length of vertical pipe that extends at least 25 centimeters above the top of the tank. The pipe inside the tank that extends to the center is the esophagus, the pipe outside the tank is the cows throat. For a better mouth you put a funnel on top of this "feeding tube".

The cow's ureter.

At the very top of the 1000 liter barrel, on the opposite side from where you drilled the hole for the feeding pipe drill (or melt with a piece of hot pipe) a hole for the 1" tank adapter. On the outside of this connect a short length (~ 10 cm) of 1" pipe, then an elbow and then about 20 cm of 1" pipe -- this is for the exit of excess fluid. You place a 20 liter bucket under this "ureter" to capture the fertilizer. You will always get as much fertilizer in liters as the feedstock you put in to the mouth (i.e. if you pour 10 liters of ground up food and water in the mouth you will get 10 liters of "cow pee" out at the same time).

The cow's intestines.

You want to have as much surface area for bacteria to grow on and form their biofilms as possible. Fill the bottom of the 1000 liter barrel with stones and gravel of various sizes up to about 5 cm. You can also throw in plastic chips. One way we improve performance is to place a stone in the bottom of a net or mesh bag, fill the bag with plastic balls or chips and sew a piece of styrofoam at the top so the net bag floats vertically. The bag can be almost as long as your tank is deep and you can put several in. these become what we call "bacterial fuel rods" -- places where the bacteria can breed and form active biofilms. You are basically trying to recreate the villi in a cow's intestines.

The cow's bowels:

Take your 750-liter barrel, which will become your "gas collector" and cut openings in the top in the curved part, leaving enough of a skeleton of plastic to support the center ring of the original opening. Then press this ring in so that it is concave instead of convex. You want to leave this ring of plastic for two reasons -- one so that as the tank moves up and down as it fills with gas and you use the gas it will agitate and mix the water and food slurry to make sure the bacteria at the top get food too and two to provide weight and stability so that the tank rises in a more vertical fashion and has the mass to force the gas out as it descends.

The cow's anus:

Drill or melt a 1/2 inch hole into the bottom of the 750 liter tank (this will now be the top of the gas collector). It doesn't matter where you place this hole, but we generally put it about 5 cm from the edge of what will be the top so it can be closer to the kitchen and so we can place weights (bricks, potted plants, etc.) in the center of the collector to help pressurize the gas. Insert the 1/2" tank fitting and put on the elbow, the valve and the brass 1/2" pipe to barbed hose adaptor. Attach the clear plastic hose to the barb with a hose clamp and run the hose to the kitchen. Attach the other end of the hose to a stove burner.

After the barrels are equipped test them with water to make sure they don't leak. Tighten tank fittings as necessary.

Preparing the system to produce biogas:

Fill the 1000 liter tank with approximately 300 liters of water and then mix between 40 and 80 kg of fresh animal dung with water, breaking up any clumps under water and slowly pour it in. You don't want to expose the bacteria to air so try not to introduce a lot of bubbles as you are mixing. We've used dry animal dung in Palestine and it worked, but you are likely to get better and quicker gas production if the dung is still moist. You can get quicker results if you store the dung for several weeks in an airtight container before adding it to the digestor. You can also avoid the use of dung altogether if you have a source of liquid from somebody else's active biogas digestor. The more you add, the quicker you will get gas because this is all about building up a large healthy population of bacteria.

After you have added all the dung, continue to fill the barrel with water until you reach the overflow hole (the ureter). It is advisable to plug the ureter hole at first so that you can fill the barrel with water all the way to the rim so you can completely submerge the gas collector barrel and drive all the air out.Put the 750 liter barrel upside down into the 1000 liter barrel and open the 1/2" valve at the "anus". Press down on the 750 liter barrel to force the air out and to press it all the way down until it is completely submerged and is nested inside the 1000 liter barrel as far as it can go. If there is still a small airgap because your 750 liter barrel is slightly taller than the 1000 liter barrel (specifically because of the feeding tube or "esophagus" and the gravel, rocks or bricks on the bottom of the tank) this isn't a grave problem but it will slow down initial gas production because the aerobic bacteria need to consume all of the air first and die out before the anaerobes take over.

Wait until the anaerobic bacteria have reproduced and become active and start producing flammable gas before feeding. This can take around 2 to 3 weeks depending on the temperature; we've had systems in colder climates take several months. On the other hand we've had systems in warm environments start within a couple of days. When you use somebody elses active biogas effluent you can achieve flammable gas within 24 to 36 hours.

Be patient.

Regardless of how long it takes, try to avoid feeding the system anything until you are able to ignite the gas. The first days to weeks gas will be produced but it will be mostly CO2 and will extinguish a flame. Do a flame test every couple of days (or just wait if you have the patience). You will see the 750 liter barrel start to rise and when the CO2 concentration drops from 100% to about 40% you will have nearly 60% methane which will burn quite well and safely and will produce a clean clear blue flame.

At this point you can start feeding your system. Start slow -- you have to acclimatize the bacteria to high energy and complex food; actually their are many types of bacteria in your system that need to work together -- hydrolytic bacteria need to break down the food, acidogenic bacteria turn the breakdown products into different acids (propionic acid for example) and carbon dioxide, and acetogenic bacteria break these down into acetate and carbon dioxide which are the real foods for the methanogenic bacteria that make the biogas. To acclimatize them without overwhelming them start out with about 200 grams of food, then work your way up each couple of days by doubling to 400, then 800 then finally between 1 and 2 kg per day. For a 1000 liter system you don't want to exceed 2 kg each day because the water can turn acidic and the low pH will kill your bacteria (if this does happen, either wait for the pH to rise back to between 6.5 and 7.5 or add some baking soda or another buffer -- if some of your bacteria survive the acid event you will just have to wait until their numbers are strong again, if not, re-innoculate with fresh bacteria from either dung or somebody else's effluent. It is a good idea to store some of your own effluent in an airtight jerrycan just in case, and it never hurts to dump dung in from time to time if you have access to it). Do NOT overfeed your system - giving it more food will not give you more gas. A 1000 liter system (1 cubic meter) can give up to 2 hours of cooking gas on 1 burner per day when the temperature is at its optimum of 37 C. In the winter near Mumbai in India they get about 1 hour a day, 2 hours in the Summer. It is best to situate your tank where it gets the most sun each day; black tanks are best; if you only have white tanks, paint them black. In colder climates you will need to put a heat exchanger in the tank and connect it to a solar heater or a compost heater or even use 20 to 40% of your gas to raise the temperature to between 30 and 40 C.

Using your home-made biogas in a kitchen stove:

It should be noted that in order to use butane gas stoves and make them run on biogas you need to make a simple amendments: he first is to expand the gas exit hole (nozzle). This usually simply involves removing the restrictor pin where the gas from bottled gas enters the stove. Because biogas is generally under very low pressure and because it contains about 1/3 carbon dioxide you need to supply gas through a larger opening to get the same amount of thermal energy. The second amendment you might need to make is to minimize the air intake because the biogas won't need to consume as much air as high flow pressurized gas. By adjusting the air you should be able to achieve a clear blue flame with no yellow streaks in it.

Benefits of home biogas:

The home biogas system eliminates your kitchen waste and produces gas and a very rich liquid fertilizer that can be directly applied to plants or your garden. If you let the effluent dry you can use the cakes that remain as a solid fertlizer.

Benefits do not stop at this point --- another application that we have been experimenting with in Egypt is the production of electric power using a modified generator. The modification uses a $190 'tri-fuel' kit from US Carburetion and takes only about 15 minutes to convert. Per cubic meter biogas can generate electricity ranging from 1.3 to 1.5 kilowatts/hr.

Beyond the benefits of using biogas as a waste disposal,solution which is in itself a significant feature, the other benefits of biogas qualify it as a fantastic alternative energy source that can be used without purification or treatments and causes no air pollution -- it can thus replace bottled gas, wood and charcoal and not only reduce respiratory illnesses and the use of fossil fuels, but take pressure off of our dwindling forest resources, saving and protecting habitat for wildlife and protecting watersheds.

Biogas is relatively non-toxic, is colorless and has no odor when it is burned. When it is not burned it has the odor of natural gas (a slight tinge of hydrogen sulfide) so one can easily detect a possible leak and take appropriate action. It has a flame speed of 35 cm per second, slower than natural gas - which actually makes it safe. It has a thermal energy content between 5000 to 6000 kcal per cubic meter. Chinese experiments have proven the following practical applications that 1 Cubic meter of biogas (the normal output per day of a household system using a 1000 liter barrel) can provide:

Run the stove for an average of 2.5 to 3 hours.

Run a lamp of 100 candle power for a period of 8 to 10 hours.
Run an internal combustion engine/generaotor of 1 HP for two hours.
Operate a tractor weighing 3 tons a distance of 2.8 km.
Run a medium-sized runs with a length of 60 cm for two hours.