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Saturday, October 20, 2012

Biodigester San Roque

       Several months ago one of my neighboring volunteers was in the middle of writing a grant to make a biodigester with a local farmer close to his community. My first reaction to this was, "what the hell is a biodigester?" I had heard about biodigesters vaguely over my time both here and in college, but had no real idea of what they were or how they worked. My friend Jimmy, who has since left Paraguay for a graduate school opportunity in Germany, explained that basically it is a device that can harness methane gas through an anaerobic process which combines a set ratio of manure and water. The gas it creates can be used as cooking fuel, which minus the cost of building the thing is totally sustainable. Typical Paraguayan families who live in the countryside, have cows, pigs, and chickens. Chicken excrement is the most concentrated of the three animals and, therefore, produces higher quantities of the gas, if the appropriate amount is available. You do need a lot of chickens to create the amount of manure necessary to sustain the biodigester, but families normally don’t have the amount of waste necessary from chickens. However, they do often have plenty of pigs or cows whose manure is more commonly utilized in small scale bidigesters. It takes 3-4 pigs or cows to produce the daily amount of manure necessary to create the gas. Jimmy had all but finished the application to receive money from the Environmental Climate-Change Partnership of the Americas, EPCA, when he was accepted to a very well respected graduate program in Germany. I was at his house one day when he asked if I would be interested in taking over this project when he left. This was prior to receiving the funds for the garbage project, and before we had finished planting all of our trees, so naturally I said sure thinking to myself how hard could it be?
       The short answer is I still don’t know. Next Wednesday, the 24th, along with a local farmer, Daniel Rios, and I will be putting on a biodigester workshop to present to members of his committee and the surrounding area. A big part of the application to receive funding from ECPA is to make sure the project isn’t exclusively focused on improving the livelihood of one individual. The idea is to use the money to facilitate an exchange of information using the biodigester as a mechanism to do just that. The most challenging part of the process to this point has been the coordination of everything to get us in position to conduct the workshop. 
       For starters, Jimmy was a Crop Extension Volunteer who arrived the year before I did. His training was different, and so were the projects he was encouraged to do, while similar in many respects, his projects do diverge slightly from my work as an Environmental Conservation Volunteer. My speciality group, unlike Jimmy's, did not recieve any information on biodigesters during our training. That also means that Jimmy's bosses are different then mine which meant if Jimmy submitted a grant to this project, which he did, I could not simply inherit the project from him first because I am a different person, but second because my bosses don’t know about the projects the agriculture sector is doing and vice versa. All to say, when Jimmy left, I had to start over with everything except the actual writing of the application. I needed to introduce the idea to my bosses, get their go ahead, change a few things on the application, resubmit the whole application, and wait. It wasn’t that big of a deal that I had to do all that, but it did mean that instead of doing this project in early September, like it was originally planned, I am now doing it at the end of October. Another big challenge is that the community where I am doing the project, San Roque, while very close to O’Leary, is not technically my community. This makes coordination a bit difficult at times. Part of the reason I agreed to do this was because I figured it could act as a trial project for me to do a similar project in my community next year. I’ll have to wait and see what the turn out is for the workshop is before I will make a decision if this is something worth doing next year.
       I ended up receiving the money for the project the first week of October, which put everything into high gear. With a fat stack of Guaranís in my hand, the amount for the project far exceeds my monthly salary; I set off to buy the needed supplies. Just say most of the materials I need except for two types needed for the biodigester body, tubular polyethylene and laminated polyvinal.  They can only be purchased in major cities one at an interior design store the other at a place that packages cookies. I figured these two items would come off as fairly strange requests, and that I would get asked a series of questions as to why I needed said materials in the amounts requested. Much to my surprise, and with maybe a slight feeling of disappointment, I was not asked any such question. I now had in my possession 2 huge roles of plastic, all the necessary teaching materials to put on the workshop, and my exceedingly large backpack to take back to O’Leary. As luck would have it, I didn't have to deal with the hassle of a bus ride.  One of the agricultural sector employees gave me a free ride back to my site. 
       As for the rest of the materials, they comprise a wide range of things including, plastic hose, 0.5 meters of pvc, two  large plastic barrels and an empty two liter bottle of any kind just to name a few. It took me most of the day and trips to five different hardware stores to find all the necessary materials. Lucky for me that hardware stores are one of the five types of businesses that operate in ubiquity in Paraguay. The other 4 include pharmacies, small grocery stores, furniture/appliance stores, and hair salons, so I was, thankfully, not without options. 
       A biodigester utilizes a pretty basic concept. As I mentioned earlier, the biodigester is a way to harness the gas produced by manure to burn as cooking fuel. The amount of gas that can be produced depends on the size of the bidigester. For example a biodigester that is seven meters would need roughly 5-6 cows to produce the manure necessary to make between 4-5 hours of cooking gas daily. 4-5 hours of cooking gas is a lot of gas, so what you don’t use in a day you release out into the air so as not to overflow the capacity. Biodigesters are not a new concept in the slightest. In fact, people have been experimenting with them for decades all over the world in places as far reaching as Bangladesh. It has only been within the last decade or so that the design model I am using has been implemented thanks in large part to the experimentations of Sr. Fernando Gonzales who is currently the Program Specialist for the Agriculture sector of Peace Corps Paraguay. The relative affordability of the plastics now makes building the  biodigesters far more inexpensive than previous designs which called for large amounts of cement and labor to build. According to my former collogue, Jimmy Henderson, on his website, “14 KG of cooking gas costs approximately 100,000 Guaranís (Roughly $20) which is a significant portion of a rural landowner’s monthly income.” He goes onto mention that the cost of the biodigester, a mere 500,000 Guaraní’s, (roughly $120) can save about 2,500,000 Guaranís over an 8-10 year period (

       If this project is successful, it will be interesting to see whether or not it can be sustained or built upon as a viable alternative to propane powered cooking stoves or wood burning ovens. My hope is that this workshop will help me do another one next year in my community. My only concern is it is always difficult for people to make capital investments on things of this nature. If I didn’t receive a grant to do this project it is likely that it would have never happened. The cost is a lot and finding all the materials requires several trips outside of the area where we are building it. The other disadvantage is that the biodigester itself is primarily advantageous to the family I am building it with. They alone will reap the benefits of the gas and the nutrient rich by product, which can later be used on their fields or garden. I am not sure what the future will hold for this technology in my area. HeckI don’t even know if I am going to be able to get it to work in the first place, but in most ways this is like every other project I have done to this point in my service in that you don’t know until you try.

1 comment:

  1. You know, I've never really understood how the gas is stored. I always just imagine that big ridiculous thing plugged right into a stove, which adds to my skepticism for the whole idea. Does it go into a canister or something?
    And so, if someone had a lot of animals, could they sell the gas to their neighbors? I feel like that would really make the project more attractive to folks.