Thursday, January 28, 2010

Dometic DRC4000 3 -Way Portable Refrigerator

We should investigate this 3 way portable refrigerator more. At 400 dollars on sale, given that it is an absorption chiller that can be powered by gas, OR AC or DC electricity it seems to hold a lot of promise. We need to see how it adapts to low pressure biogas and how cold it keeps vaccines and medical su...pplies, but it looks ideal for the "Rumble in the Congo". Any idea why these aren't being used there?

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Propane, 12v DC or 120v AC Powered
January 26 at 11:43pm · · · Share
Lara Morrison
Lara Morrison
On a completely different note. The Land Institute has a 50 year Farm Bill proposal you would like.
January 26 at 11:50pm ·
Edwind Suryadi
Edwind Suryadi
I have one mr Culhane, it's DC powered. I bought for 65$
January 28


The sign on the Alaskan Hotel in the quaint fishing village of Cordova, Alaska (where we are working with the students of the high school science club and scientists from the University of Fairbanks to build a new breed of biofuel reactors based on our Solar CITIES designs created in the Arab...
Thomas Henry Culhane
Thomas Henry Culhane
This blog post was inspired by watching Obama's sensational State of the Union address and quotes what I think are the best parts of it, tying his statements into our work in Alaska.
January 28 at 7:37pm · 

Wednesday, January 27, 2010

Sun Frost RFVB Super Energy Efficient Medical Vaccine Refrigerator

Thomas Henry Culhane Mike Rimoin These are the Sun Frost medical refrigerators for off-grid use in Africa at 2000 dollars each. I think we can do much better with propane or natural gas refrigerators run on waste-food biogas by a factor of 1/2 to 1/3. Sun Frost products are great but I think we are too locked into this idea of using elec...tricity for everything instead of using the thermodynamics of locally available environments and resources. In Borneo our candle-powered-refrigerator (ammonia based) kept our vaccines and snake anti-venom in great shape.

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Propane Refrigerator | Propane Refrigerators | Propane freezer | Propane Freezers | Gas Refrigerator | Propane Appliances | Gas Freezer | Gas Fridge | Gas Refrigerator | Lp Gas Appliances | LP gas refrigerator | LP Freezer
Hala Mohie Eldin
Hala Mohie Eldin
yes it's super expensive and what if we need bigger size freezers? I am so happy we are starting to do research that will actually reduce cost! and YAY for biogas, I just saw the few minutes of light produced in Mansheyet nasser video. Biogas rocks!
January 27 at 9:23am ·

Monday, January 25, 2010

Tests of Alaskan bioreactors

With 3 out of six reactors working really well, and the three that aren't being the 2 psychrophiles and 1 psych/meso mix in the cold room, we ran an experiment today that yielded suggestive evidence that psychs need high energy feedstock before they will yield gas.

January 25 at 9:09am ·
Thomas Henry Culhane
Thomas Henry Culhane
Essentially we lit up several buckets that had been filled with different amounts of psych mud and sugar and left to sit for several weeks in the cold. All flamed up except the one that had received no sugar. That one had no methane at all. I'm thinking the mud in and of itself has insufficient carbon to support effective methanogenesis. ... See MorePerhaps in the thermokarst lakes the reason we see "hot spots" of methane production is that those areas are regions of collected carbon-rich detritus the bacteria are feeding on? I would love to do a scuba survey of the arctic lakes and see...
January 25 at 9:11am · 

Sunday, January 24, 2010

BBC News - Engineers 'can learn from slime

  Doncha just love the problem solving abilities of self-organizing networks? From microbial intelligence to urban planning, I continue to believe that the best solutions are found when we let the algorithms that have evolved over billions of years work their magic; connecting community catalysts allows such algorithms flourish, and the work we are doing in Alaska helps confirm this notion!

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Scientists drew this conclusion after observing a slime mould as it grew into a network that was almost identical to the Tokyo rail system.

Friday, January 15, 2010

Threads on Compressing Biogas I found interesting

Ken Calvert <renertech at> wrote:
  Dear Michael etal, I think you have found the figures for LNG not CNG. The 
only way to liquify Methane is at a very low temperature. If you strip the 
CO2 and H2S out of biogas then to all intents you have Natural Gas, and CNG 
or compressed natural gas equipment operates at around 3,500psi, but it is 
still a gas. If you are going to compress biogas at all, then it is best 
to stick to the usual figures and then you can run you car cook your food 
and warm your house with standard mass produced Global standard equipment 
from off the shelf of any hardware/heating store. If you, and anyone else 
wants some plans as to how to do it as economically as possible then send me 
a private email and I will return mail you some brochures put out by our 
Ministry of Agriculture for small farm and hobby farm Biogas plant.
In brief, you collect the gas in a plastic bag, and monitor the pressure 
with the filler guage out of a auto washing machine. The pressure switches 
on a two cylinder air compressor which sucks the gas through one of a pair 
of barrels filed with rusty bashed up tin cans which are alternated one in 
line and the other left open to the air. The Iron sulphide in air then 
reverts to iron metal for reuse of the barrel, and the sulfur is left as 
elemental flowers of sulfur which is useful stuff. (beware heat problems) 
At around 150psi the gas is bubbled through a vertical water column 
consisting of a six meter length of 6" 150mil plastic pipe. 2metres as 
someone suggested is not enough. Natural gas at 150psi can then be used in 
liu of LPG if it is metered through an LPG reduction valve and the jets in 
LPG stuff are opened out a smidgeon. Storing a reasonable volume of methane 
at this pressure takes some ingenuity but it can be done. To drive your 
car on CNG requires a pair of old double acting hydraulic cylinders off a 
bulldozer or some such. You can't use one cylinder with a floating piston, 
because as already mentioned lubricating oil will take up methane under 
pressure and hydraulic pumps don't work too well with oil foaming out the 
tank. A single 3 ft stroke will take you up to 3000psi + in one stroke, 
and normal DIY hydraulic equipment from Northern Tool or other DIY stores 
operate at just the right pressures to make a rather neat setup. However,
let me say it again spending the money to go this far is crazy if you do 
not clean up your gas first and convert it into the Natural Gas which is a 
world wide commodity with so many appliances and equipment matched to its 
Ken C.
Scrubbing and compressing biogas makes sense only if you want to use it as
fuel in an internal combustion engine. If you want fuel just for heating,
burn the biomass as it is, and make use of its full calorific value. When
you convert biomass into biogas, you lose at least 75% of the energy in the
process of conversion.
Michael etal,   coming back for a second bite at the cherry.  There used to 
be on the market ,out of Europe,  a micro cng compressor by which an urban 
person, could take natural gas from their household supply, and pump it up 
to the required pressure straight into the tank of their car overnight.  It 
was quite small and operated at about 1/3 to 1/2 hp.  It would sit in the 
corner of ones garage and got around all the OSH regulations by not storing 
permantly anything dangerous under pressure in ones house.
    I once talked to someone else who had hooked a  hand operated grease gun 
to a 1/4 hp motor. A lever grease gun will take you up to 7000psi. 
However, he had his pressures and compression ratios all wrong  and it was 
even more painfully slow than one might imagine.   Happy compressing.
O.K. here it is!

If you scrub your biogas to the quality of natural gas, 
then you can  fill a CNG converted  car in your garage over night, 
with no problems of HP storage because the car provides the HP storage.  
I would go more and say that an enterprising person could  also use the 
CNG gas tank
of their car as storage to run ones household in the evening too. 
Bolt on CNG conversion kits are readily available from Europe.
Especially from Italy.   You might have problems in  getting it approved 
without a operators certificate as well, 
but thats a bureacratic problem not a technical one.   ATB Ken C.   

Dear biogas workers,
I wish all of you a happy new year. I take this opportunity 
to report some of my findings and poremises based on actual 
field experiences and observations.
Use of human food for generating biogas: Because the methanogens are
found universally in fecal matter, the faeces are considered by everybody to
be their food. The intestines of animals house a large variety of bacteria. 
It is my premise, that because these bacteria, including the methanogens, live in the
guts of animals, they eat what the animals eat. They are found in the faeces
because they are thrown out of the body along with faeces. The fecal matter 
represents the residual matter that can be digested neither by the digestive system of the concerned animal nor by any of the bacteria residing in its gut. The fecal matter can be digested only by a cascade reaction starting from hydrolysis to acetogenesis to methanogenesis, with a different bacterial species acting at each step. This process is analogous to biphasic systems, in which aerobic bacteria are employed for achieving partial digestion of the biomass, which is later acted upon by the methanogens under anaerobic conditions. The rapid generation of biogas from sugar or starch is most probably due to the fact that these substances are directly digested by the methanogens, without taking help of any other bacterial species. Especially in the case of sugars, biogas starts emanating from the biogas plant within two hours of introducing the feedstock into the biogas
plant, and it is digested and converted completely into biogas within 24
hours. Starch takes just a little longer. I do not advocate the use of  good
quality grain or crystalline sugar as feedstock for biogas generation. 
One should  use urban food waste for this purpose. In fact, its disposal is looked
upon as a problem by the municipal authorities. Our technology offers a
solution to this problem.
Failure of biogas technology in India: India has about 145 million rural
families. Even after 60 years of efforts on the part of the Government of
India, we have in this country only about 3 million working biogas plants. 
The low penetration of the biogas technology in India is primarily due to the 
high cost of the dung based biogas plant and also due to the fact that the
government promoted  biogas only as cooking fuel. Had it been made known to 
the villagers that biogas could be used as fuel in an internal combustion engine
for generating electricity or for pumping water, the villagers would have accepted 
the biogas technology wholeheartedly. 
Biogas as fuel in an internal combustion engine: volunteers of a U.K based NGO 
called Engineers Without Borders standardised this system in collaboration 
with our scientists. In this system, unpurified biogas is used as fuel 
in an internal combustion engine..A large number of people, including us, 
are making use of this technology. We use one internal combustion engine for
generating electricity at our campus, and another internal combustion engine 
for driving our char briquette extruder. 
In the area where our R & D centre is located, we get electricity only for a
period of 12 hours in a day. Several farmers and restaurant owners in our
neighbourhood now generate their own electricity by using this technology.
They use biogas generated by them in their own biogas plants. 
Farmers use cattle dung as feedstock, whereas the restaurant owners use food waste.

Failure of biogas plant at Approvecho: A team from Approvecho had visited 
our campus and seen with their own eyes the working of our biogas plants
made from two water tanks. I was with Approvecho only for a period of 4 days.
It was the beginning of February. The temperature at that time was below zero. I
had sent to them, in advance, our video CD and a list of the hardware needed
for fabricating a biogas plant. I was informed that everything was available 
in the local shops and that the hardware would be purchased after my arrival
at Approvecho. When we actually tried to buy the hardware, we found that
the tanks of specified sizes were not available in any of the shops.
They were listed in the catalogues of the manufacturing firms but not 
available off the shelf. Therefore we had to improvise, 
using discarded barrels obtained from grocery shops.
Therefore, instead of a moving drum model, 
I constructed a fixed dome biogas plant with the available material.
With the short time available to me, I could only assemble the hardware 
and leave without actually commissioning the plant. 
I heard later that the plants fabricated by me at Approvecho did not work,
but there was nothing I could do about it as I could not visit USA again 
just to repair the biogas plants.
Efficiency of a biogas plant: 
If, instead of fermentation taking 40 days, 
I got the same amount of biogas within 24 hours, 
I would consider the process to be 40 times efficient. 
If, instead of using daily feedstock weighing 40 kg, 
I got the same amount of biogas with just 2 kg feedstock (e.g. stale bread),
I would consider the process to be 20 times as efficient.
Multiplication of the two process efficiency figures gives you the 
total efficiency figure of  800.
Use of effluents as fertilizer: 
The effluent of a biogas plant contains most of the
minerals required by plants and it should therefore go back to the fields.
There is however a problem in an urban environment, 
because there are no fields in the vicinity. 
The slurry from our domestic biogas system is generally poured by the users 
into the toilet and flushed away.
Compact biogas system gives insight into agriculture: 
There is universal agreement among soil scientists that there exists a
positive correlation between the microbial population density in the soil 
and soil fertility. The reason for this correlation is that the
soil micro-organisms can make minerals in the soil available to the plants.
Agronomists recommend applying organic matter to the soil in the form of compost
in order to feed the soil micro-organisms. Our work on biogas showed that 
high calorie organic matter worked much better as feedstock in a biogas plant 
than a substance like dung, having a relatively low nutritional value. 
I tested the same concept in agriculture and got excellent results, 
when I applied sugar or green leaves to the soil. Just 10 kg (dry weight) 
per acre (25 kg per hectare), applied to a field, once every 3 months, 
gives as high yield as a field receiving the full recommended dose of 
inorganic fertilizers. Literally thousands of farmers in my state are now 
using this technology. Critics call this method soil mining,
but one should keep in mind the fact that just 1 meter layer of 
soil contains enough minerals to support agriculture continuously 
for 25000 years. The earth's crust is 100 km thick. 
A.D.Karve, Jan 01, 2009


Sunday, January 10, 2010

BBC News - International nuclear bank - helping world peace?

Thomas Henry Culhane 

I absolutely hate nuclear power as a terrestrial solution to the easy problem of providing electricity (we have so so very many absolutely safe, clean and easy methods to produce electricity -- biogas from garbage is one I'd like to see used everywhere and only when all the garbage is gone from the streets and landfill...s would we move on to more expensive options) . But if the politicos think we must have the "deadly terrorist-vulnerable radioactive rocks -to-heat water-to-turn-turbines" option, this Eisenhower solution, now backed by Obama and Russia, seems to be the way to go. Please support it and convince Egypt to support it as well, since they are a key country with immediate nuclear ambitions that could make this work or scuttle it.

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In 1953, eight years after the American nuclear bombing of Japan, President Dwight D Eisenhower laid out a vision that he called Atoms for Peace.

Friday, January 8, 2010

Movie Review - Garbage Dreams - The Struggles of Cairo’s ‘Garbage People,’ but No Whining - NYTimes.

Thomas Henry Culhane  

An excellent review of the marvelous film about our friends from Spirit of Youth! You can actually see the very first hand-made solar hot water system we built on the roof of the Zabaleen school in this photo, and behind the camera is one of our experimental urban-waste-to-biogas digesters that can help replace the fun...ction of the pigs that were slaughtered. See the movie and if you can, help us get Clean Development Mechanism (CDM) funds to the community to help Adham and Nabil and Osama reclaim the Zabaleen's world-record recycling rate of 80% through waste-to-energy systems (with proper funding we can even turn sewage waste into clean fuel for electricity production). (PS, Yes, this is the very place and people that Professor Randall Crane's UCLA Urban Planning students visited in 2006; thanks Guillermo and Jane for sharing!)
“Garbage Dreams,” directed by Mai Iskander, follows young people who collect trash in Cairo, a city of 18 million residents that has no official sanitation services.

EGYPT: Plenty of Sun, Nobody Catching any Rays - IPS

Thomas Henry Culhane  

This excellent article captures many of the points that were in the chapter on solar heating of water that I had to cut out of my dissertation. I recommend it to anyone who wants to know why Egypt uses so little solar hot water (400,000 m2 for 80 million, with half not working (!), compared to neighboring Israel's 6 million m2 for 6 million people) . However in this "new Obama era" (with the American juggernaut that controls Egyptian energy policy finally adopting European sensibility) "many Egyptians [are] thinking that if European
energy users see the commercial viability of generating solar energy in Egypt
and transporting it thousands of kilometres, surely Egyptians can do it in
their own backyard."
Egypt receives some of the highest annual solar radiation in the world, yet the desert country remains heavily dependent on fossil fuels.

January 8 at 12:41pm · ·· Share

Friday, January 1, 2010

Digestor 7 produces methane

Yay! Sugar-fed Psychrophilic telescoping digestor (#7) has started producing flammable methane! In other good news, I've finally cut the text of my thesis down from 400 pages to 154 pages and resubmitted. Fingers crossed that I didn't throw out the baby with the bathwater! Apologies to family and friends whom I've neglected during these long days of focused editing!!

See MoreJanuary 31 at 9:51am · ·
Stephen H. Kiss
Stephen H. Kiss
drove a GM fuel cell car today. very cool
January 31 at 6:13pm ·
Thomas Henry Culhane
Thomas Henry Culhane
That is very very cool Stephen! I once drove Councilman Eric Garcetti's EV1 (before "they killed the electric Car") and it rocked! But a fuel cell car... WOW!!! Hope you'll post more about the experience!!
February 1 at 8:56am