Hello all!!! I am hoping to install a hydro plant this fall. I have some major questions. First I'll explain my site, then the questions.
We have a creek running along our property on a pretty steady grade. We have 26.4ft of head and an 825ft run of penstock. I'm planning on running my penstock down the creek to avoid freezing. I have a 3kw turbine from china, supposedly rated for 236gpm - 394gpm. Because the penstock follows essentially the same route is the dream, the water in the pipe will be moving at essentially the same speed as the water in the river. Correct? So far so good.
The question I have is the penstock. The pipes. How big do they need to be???
The Chinese dealer is telling me that 110mm pipe is plenty, thats about 4.5inches. BUT, at our water speed, according to the friction chart for poly pipe (the kind of pipe I want to use) the output is only 5l per second when I need at least 15l per sec (236gpm).
So my question is, whose wrong, me or my Chinese dealer, and why?!!
C, I realize what you say is true, too many factors. It's like trying to get a grip on how many hours the motor one is using for a CHP system will last. Almost impossible. But I like to have at least a ballpark figure.
Call to ALL CHP enthusiasts. I am putting together a CHP (combined heat and power) unit based on a wood gasifier. Syngas will be created and piped into a Kohler Aegis 26hp LH690 which will turn a generator which will power a battery bank which will power our farm. I do not need so much power but this is the smallest commercially available gas powered water cooled engine that I could find. It produces 26hp at 3000RPM. Question. Is there some reason I could not set the governor to run the engine at 1200 RPM? Acording to the power charts for this engine that should give me about 7-8hp which, although still more than I need, would put me in the ball park of my energy goals. I am also thinking this should significantly reduce the engine wear and tear per hour and should therefore significantly increase the engine life. These engines should get about 10,000 hours as is, I am thinking (hoping) I could get 20,000 plus hours if I run it like this. What do you say? Am I crazy? On the right track?
Also, if you know of another low power liquid cooled engine which you think would work better in this set up, let me know!!
Su Ba, I can only agree with you. Sounds like you made the right choices and are reaping the benefits. A huge benefit to me, and no way can it be quantified monetarily, is the benefit of self reliance. Knowing how to make your own power, how to troubleshoot and fix problems, make you, somehow, more alive. And if the set up fee of getting grid power is more than or at least the same as the initial set up cost of an alternative energy system, then you are really in that small category of people who are even making an economically astute choice.
The thing of it is, is that I am looking at my current situation (hooked up to the grid) and desperately trying to make a case for the economical reasons to set up an alt energy system, and they are not there. But we are planning on moving within the year, to set up a new homestead and large farm (about 200 acres) and that land has no power, and getting power will cost between $25,000 and $100,000 (we are looking at several properties) and when we do make the move, oh I really want to set up my own electrical system.
I do understand the "lifestyle" aspect for me, but it at least has to make some marginal sense economically, for me, as well.
Im under no delusions that home made power will be as cheap as grid power. But I still like to count my costs.
So far, it seems that battery banks will run as a constant system cost between $0.31/kW to $0.13/kW. depending on upfront investment (pay more up front, cheaper over time; pay less up front, much more expensive over time).
Add that to a constant depreciation cost of panels at $0.14-$0.29 per kW and yeah, no delusions.
I've been waiting for this for a long time. It doesn't "look" like an engine, but it is an engine! A stirling heat engine. And the price, although high, is way more reasonable than anything else I have ever seen!!
Greetings Fellow Permies! A quick question to the informed, the experienced, and to the notably non newbie!
How long will a battery bank last? How long did your battery bank last? I'm reading such wild and crazy ranges as to be useless for computing costs. Lets say if I am looking at my alt energy system costs over 20 years, how much will I need to plan on spending on batteries?
Deep Cycle 12v - 24v batteries?
Industrial (forklift) 12v - 24v batteries? Crown vs. GB or other??
NiFe batteries? China vs. USA??
I posted a long time back about how batteries seem to be the oft overlooked Achilles heel of alternative, off grid, energy. I'm still of that opinion. However there is no way around batteries. You can opportunity load, you can get very energy efficient, you can cook on gas (methane!!), but in the end, if you want a "modern" feel to your lifestyle, you are going to need some batteries. So it seems that the cost of batteries OVER TIME is the biggest question, cost wise, of a system. And just wild claims of 4 years to 20 years life spans have left my head spinning. Love to see all your thoughts!
Sarah, The expense of Solar is the prime reason I started seriously investigating gasification tech. Again, the tech has to be appropriate for the application, and in your case it may not be. In my case, 7 months out of the year we have very limited sunlight and not very strong light at that. Our farm needs 12 kw per day to operate. Because of where we live, Siberia, I'd have to install 3 times the amount of solar panels to get us through the winter than I would have to install to get us through the summer. I'd need to install about 12 generic 200 watt panels to produce our energy needs 5-6 months out of the year. This is already a big expense. But to get the remaining 6-7 months covered, I'd need an additional 28 panels!!! And that's just crazy! I could save some panels by adding a larger (much larger) battery bank but that only helps marginally. PLus, with ANY solar system you need to have at least 3-4 days worth of battery backup power in case of stormy weather or serious overcast, and that battery bank isn't cheap either. The way most people save money on the battery bank is to get a generator for backup.
So any solar system will consist of PV panels, battery charger, battery bank, inverter and usually a backup generator. So I said to myself, why waste the money on 3-5 days battery bank plus a generator? why spend 3-4 times the money on PV panels to run through the winter?
Why not put up enough solar panels to get me through 4-5 months in the summer, say about 10 panels (instead of 40!!), put in 1 days worth of batteries instead of 3, and get that back up generator I would need anyway, and only add one extra item to the system, the gasifier to supply free fuel to the generator. I buy the plans, pay someone to build it for me, gasifier cost about $2,200 all said and done. What I saved on batteries and panels is way more than this little addition. Maybe in the future I'll add a simple chinese made turbine for wind (you can get pretty good ones not too expensive on Alibaba). And thats how I came to embrace gasifiers.
IT may not work for everyone. It may not work for you. You may have a situation where 10, 200w PV panels will be enough for you 12 months out of the year. But for me, I had to use solar energy in the hard form, that is wood.
Any way, I hope that maybe cleared up my thinking process for you.
Back to biogas.
Using human waste in a biogas reactor, with all due respect to journey to forever, is probably a bad idea. First off, the human body is very very efficient compared to cows or horses or even pigs, and there is not that much potential gas in our poo. Very little potential gas, but a lot of potential pathogens. Biogas reactors use anaerobic digestion, that means without air, which means they don't produce heat, which means the pathogens don't get fried, like they would in a compost pile. So better to compost human waste in a good, very hot compost pile.
Producing electricity out of biogas, on a regular basis, will demand a lot of biogas. There are about 24,370 btus in a cubic meter of bio gas. For comparison, my family uses about 17,500 btus worth of heat energy from gas per day to do all of our cooking right now. Lets saw=y you have a 2kw generator. That generator will use 35,400 btus of energy per hour, or almost 1.5 cubic meters of gas, per hour. If I wanted to run my farm on biogas, i'd need to produce at least 12 kw of energy from my generator (put it in a battery bank and use it when the generator is not running). I'd need 9 cubic meters of gas per day, or about 10 of those 1000 liter tubs to keep the generator running 6 hours a day. Actually more because there are losses involved with converting to the battery bank and converting back to AC but I think you see the point. As a back up fuel, to use occasionally, maybe. But as a full time power solution, I don't think you want that big of a system.
Ofcourse I have no idea what your power needs are. Maybe your power needs are far less than mine. I know I could gt down to about 9kw per day If i tried. But I like having the extra power. Just my thoughts on the Issue!
Gasifiers are something I do know a lot about, and am rather passionate about as well. But like all applicable technology, it needs to be fitted appropriately to the situation. The basic prerequisites of gasifier tech are 1). an abundant supply of cheap carbon based fuel. 2). a need for heat. The second is not 100% necessary but if you are going to feel all the benefits of gasification, using the waste heat created by the process (when connected to a generator) is the way to go.
But, what is gasification? Basicaly it is a way of "cold burning" carbon based materials (wood, nut shells, sawdust, etc) to break the carbon bonds and release the hydrogen, nitrogen and methane contained in the materials. "Hot" burning is what you do in a normal fire, combining oxygen and enough heat with materials to create light lots of heat and smoke. "Cold" burning, otherwise known as pyralosis, as I mentioned above, breaks the carbon bonds but does not burn the gasses emitted by limiting the amount of heat and oxygen in the reaction. This process is called, as I mentioned, pyralosis, or gasification! The device used to accommodate this process is called a gasifier. Imagine the gasifier a a kind of stove, that you put carbon based material into, but instead of getting heat and light from it, you get a flow of gasses out of it. This gas is called producer gas or syngas. The gasifier unit also has a filtration system, to filter the ash and tars out of the gas, and a cooling system, so the gas is at an appropriate temperature for use on the exit.
Once you have gas coming out of the outlet valve of your gasifier, there are a number of things you can do with it. One of those things is to use it as your fuel source for an internal combustion engine. During WWII over a million vehicles were powered all over Europe using gasifier units that were built onto the vehicle. A person could load up the gasifier with wood chips, light the hearth, get the gas producing and take off down the road, no petrol needed. This is old tech, but modern advances has made it far more accessible. Personally I do not see the Automotive function as that useful, maybe in extreme crisis or to run farm tractors or trucks, but not for "normal" driving. However there are plenty of people who would argue with me on that one!
The area where gasifiers, in my opinion, have a real place, are in back up generators for off grid applications. The gasifier converts wood, or any other carbon based fuel source, into a vapor gas that can be burned directly in an engine, driving a generator, which in turn charges a battery bank. The "waste" heat from the engine could then be used to heat something, for instance a biogas digester.
So to get electricity from firewood, or other organic material, we use a gasifier to convert the wood to syngas, an engine hooked to a generator to convert the syngas into motion and heat and electricity. The electricity is stored and used by the homestead in lights or pumps or whatever, and the heat is used to heat something.
So that is that! If you want to learn more about gasifiers, here are some links…
Rebecca, The Biogas Handbook by David House keeps coming up as the authoritative work at the moment. I was hoping to maybe see if someone would come out with something else before I put the money down. But so far his looks like the best bang for the buck!! Thanks for the suggestion. Hope you get your system up and running soon!!
Sarah, glad my comments could be useful. If you use a batch design, you will want to build a digester out of two 1m3 plastic tanks which you mentioned. Connect this to an inner tube reservoir system which you can use to create pressure in your system. Two tanks because when you add material, the digestion process slows down for a few days, then picks up again. I like the batch design because it allows for more fully decomposition of material, but it has an ebb and flow in gas production. My system will use four of these 1m3 plastic containers one of which I will refill every 15 days or so. This will give each container about 60 days to fully decompose the feed stock.
Your question about converting LPG or natural gas appliances to biogas is understandable. One of the reasons why so little information is available on the web is because, frankly, there is very little to convert. Basically your conversion comes down to pressure, flow rate, air mixture and cleanliness of gas. Of these, the quality of the gas is the most important, that's why you find more discussion about it. Well cleaned biogas means you will have fewer problems in using it in your appliances.
When you talk about appliances, there are two kinds. Smart and dumb appliances. In the Dumb category is cooking ranges, lights and engines. They are basically on or off, they are pressure sensitive but only marginally. Smart appliances are anything that either electronically or physically regulate the flow and or pressure of gas automatically. These will be much harder to convert to biogas than the dumb appliances. Fridges, water heaters etc. The main thing is to have a gas reservoir (like an inner tube reservoir) which you can pressurize at a constant level to get constant pressure. Once the problem of gas purity is solved, and the issue of pressure is addressed the next issue is air mixture rate configuration. Most gas stoves or LPG appliances have an air mix adjuster near the area in the appliance where the burning happens. Once you find the air mix valve (sometimes nothing more than a bolt or screw that is tightened or loosened) you simply adjust that till the flame is blue, not yellow. The last issue, flow rate, is the hardest to address. Biogas has less btu's than either LPG or natural gas. So even with the same pressure and the correct air mix and the good clean gas, you still may have trouble with burn rates. In dumb appliances, you just turn up the heat. No problem. In smart appliances, which have complicated adjustments of their own in their small mechanical or electronic brains, this can be much trickier.
LPG has about 2500 btu's worth of potential heat per cubic foot
Natural Gas has about 1000 btu's worth of potential heat per cubic foot.
BioGas has about 660 btus worth of potential heat per cubic foot.
So, for instance, converting a natural gas stove to run on LPG is easy. You get a 2.5 limiter to limit the flow to the device and your good to go. Getting an LPG stove to run on natural gas, however, is harder. You have to INCREASE the flow by 2,5 times. When you start talking about biogas, you start seeing even greater differences in flow rate demands. In dumb appliances this is easy, just turn up the heat, open the gas valve all the way. In smart appliances this usually means either increasing pressure to the system (could be dangerous) or more often drilling the holes in the burners to be larger. Either of these options can be dangerous and takes some trial and error.
I have personally decided to run my range off of BioGas and keep a conversion kit on hand for an engine, but to not bother with any smart appliances. It seems to me that using solar, wind and back up generator connected to a gasifier (or biogas!) can easily produce enough electrical energy for lights, electronics, water pumps, refrigerators and other electric motors. Using solar thermal, rocket mass heater, the waste heat from the backup generator and if need a "dumb" on/off biogas water heater to supply all the domestic hot water and heating needs seems to me you can get around using electricity to heat anything.
Have you read "A Chinese BioGas Manual"? It has all this info and more. Their designs are usually about 10 times bigger than needed due to their cold weather applications, so just keep that in mind. But a lot of good info. Including conversion kits or how to make your own appliances from scratch, like bamboo and clay!! I'm attaching it to this post for you.
If you are willing to pay $25 here is a book that everyone seems to think is the best on the market. I recently started a thread to see if anyone could give me better book recommendations but so far no one is biting. Here is the link to the book sales page.
Hope this helps answer your questions. Energy is just another part of the ecosystem we need to live and to thrive in comfort. Nature almost never solves any problem in a single way, but uses interconnected systems to obtain synergy and solve problems with synergy, not just raw energy. Rocket mass heater, Solar thermal, Biogas, solar electric, wind, battery bank and generator with a gasifier (and or biogas) fuel source, and suddenly you have an abundance of energy, locally available and inexpensive to maintain! The beauty of synergy!
Greetings to All! I am a book worm. Like to have a book on my shelf as a resource for any project I have done or am doing. I've asked for Book recommendations before in the past and all of you folks on Pemies.com have been very helpful. So here is another book suggestion I'd like to have, a good book on biogas! Any one used one, built by one? Love to hear your suggestions!!
Greetings! I have little real life experience with biogas but I have read, watched, listened and observed a ton. Basically 3 cows will give you (very roughy, and I know the veterans and the purists are screaming at their screens now but nonetheless) roughly the equivalent of a 50 lit propane bottle a month in biogas. So with all your animals (again, very rough but good enough for ball parking), excluding the sheep because they have very low volatile solids and their manure is less conducive to turning into gas than the other animals you mentioned, you are looking at having roughly the equivalent of 3-3.5, 50 lit bottles worth of propane in biogas per month.
Now this is not to suggest that you pressurize the gas into bottles (you shouldn't) or that you'll always get the same amount (you won't) or to say that methane has as much energy as propane (it doesn't) but its a nice way I've found of visualizing use. What could you do with 3 to 3.5 50 lit bottles of propane? That is roughly what you'll be able to do with the methane you produce from the animals you listed.
Your best bet with energy, like with everything in nature, is to have diversity. It gets the economic law of 80/20 working for you as opposed to against you. Taking methane, turning methane into electricity via an internal combustion engine, and then trying to store that energy for reuse later, is going to be a very low efficiency use of a gas that is very useful elsewhere and not that easy to get. So yeah, run what you can off your propane directly, this usually means a range or and other heating appliances like a water heater. Maybe a fridge.
Setting up a small solar array for lights and electronics, maybe with a small wind turbine to supplement it. Setting up a gasifier connected to a generator to gig you extra power to run your pumps once a day and to top off your battery bank on cloudy days, will cost not that much and will give you far more energy security than trying to do it all, all one way.
Thanks Emil for the reply. We ended up keeping up pasturing, thanks for that tip. We started giving them an oat and fennel slop twice a day and milked 3 times a day for three days and then back to the normal 2 times a day. Got all of the cows back up to about 80% where they were before they got lost, except the youngest cow who is up to about 50%. The two oldest cows are almost 100%! Fennel and oats.
Hey fellow permits. I operate a small dairy in Siberia, Russia. We are not allowed to actually homestead land, so all our cows are free range. A few days ago they did not come home, we went out to look for them and could not find them. Long story short they were gone for 2.5 days and missed 5 millings (two mornings, two evenings, and a morning). We have six milkers. Two seemed to be ok, milked them out and they have kept giving, less but not tragic, but four of our good milkers are down to a little over a cup each. It's an unprecedented tragedy for us, might be the end of our operation, in as much as milk is our main cash crop.
So the question is this, what can be done, if anything, to restore milk production. I am milking them 3 times per day now, keeping them in the barnyard, bringing fresh grass and hay for them, mixing oats and fennel into a slop for them. Anything else I should, could be doing???
Hello Everyone! I know I've been posting about problems lately, but when it rains it pours, I guess.
We have been having a problem with our goat milk souring way to quickly. Like 1-2 days and the jar is sour. Not only sour but kind of slimy as well. Earlier this year our milk would keep for 7-8 days in the refrigerator nor problem, but for the last three months or so there has been no consistency. It will keep fine for a while and then we'll have a week where every other batch just sours so quickly.
The trouble seems to have started when they went from being fed hay to grazing, but I could be wrong.
What is not the problem: I have controlled all the goats (8 milkers at the moment) separating their milk out systematically, and it does not seem to be one particular goat. We clean all our jars and utensils very throughly. We clean the goats udders very thoroughly at EVERY milking, we use a separate room for milking other than the stalls.
My eight does gave birth to 13 kids (some of the kids did not make it but our total healthy kid count after the first couple weeks was 13). Two died from angling themselves in the gate. Fixed that problem. My wife and I went to buy a car and were gone for a week. When we got back five of our 11 goat kids were diarrhetic. We called the vet and the vet said they were malnourished. I was baffled because they always have plenty of food and water. So we followed the vets instructions on how to bring back appetite, cleanse the stomach from potential parasites and get them more nutrition. Goats still dying. Wife got online to look up symptoms and they seem to match listeriosis. One of the kids that was doing very poorly this morning I just put down because she would not drink or eat anything and had the pre death look.
I've got two left. Vet won't answer my calls. Should I put them down to keep the other seemingly healthy kids healthy? I've got eight kids left that look alright, one seems a little week but she been small and week from day one and that may be me just seeing into things. We got blood work done in April and everything was clear.
My wife also had a miscarriage in April at five months and now she is afraid that maybe she picked something up from the goats that killed our baby and is now killing the baby goats.
Any thoughts would be helpful.
PLease keep in mind that we are in a rural location in Siberia, Russian Federation. No vet supply store, limited drug store, herbal remedies and home brews and human meds is what we mostly have access to.
I've been planning on putting a gasifier on our farm truck for some time and also building one for powering a standby generator for the house. I was wondering if anyone has had any real life with the kits, plans and or products out there and if any one would like to compare and contrast. Below is a let I compiled. I don't think this has been discussed here yet. So here goes!
Totally new players. Looks simple enough and the price is good when compared with the others. Need input!
These guys are new as well but they look really slick and they are priced decently. Again, looking for some real experience and input!!
Victory Gas Works - But unless someone can say something REALLY awesome bout these guys that would justify gasifying $38k, I don't much consider them an option. By the way, I asked a similar q on the DOW forums and didn't get much response except how good the Victory gasifier is so, maybe it really IS so good but the price, the price!!
Arvid Olsons International Supply Co's units Beaver Energy plan books
Herb's Welding and Machine Shop (Herb Hartman the woogassing Caddy driver)
TEI in SW Missouri offere WK formed shell kits
Sean Frenches Gasification Services for custom builds for vehicle and generators
DOW Chris Seymours Superior Gasificartion "Elit"
And last BUT NOT LEAST the DOW official "Keith" gasifier.
Any real life experience would be really appreciated. I have two basic applications, as I said, a farm truck and a generator for backup. I want to build two gasifiers for my farm in siberia and my parents want to buy two gasifiers for similar purposes in Idaho, USA, so any input would be great.
I've Got 11 village goats, a mutt breed. I am in the middle of kidding right now! So far 6 have had there kids. 13 total. Of which 3 were born still and one was born feet first and died within 24 hours. IS this mortality rate normal or acceptable or am i really missing things up??
Thye have grain and hay and fresh water twice a day, a warm barn with plenty of light and fresh air. What do you all say?
I'm at 57.61 N 96.7 E. No permafrost yet. But cold as anything in the winter. I'm really trying to eventually get my growing season from March 1 - Dec 1, instead of May 20 - Sept 10! So 3 season as well!
I think we can do it too. I'm just beginning to wonder if a RMH might not be better than a Jean Paine pile. We'll see.
1). Have to buy bags here. Bags cost $0.30 new and $0.24 used. No free bags that I've found. In fact when I buy feed or flour I have to bring an empty bag to exchange for the full bag!
2). Chicken wire and barbed wire, not cheap.
3). I'm basing my assumptions on a cement based plaster. The blocks don't need chicken wire and they need a very nominal coating. Now if I could use a more natural plaster (stucco or cob or adobe) then I might be able to do earth bags cheaper. I'd have to recalculate. I've never done anything with adobe or stucco or cob and would like to learn. Gypsum? Maybe. Cheap as dirt hear.
4). My floor is a HUGE cost factor. Could I do a floor in cob, adobe or stucco? How clean is that? How cleanable? Waterproof? If I spill a pitcher of water do I get a mud puddle in the middle of the kitchen?
5). Heating system. I said I planned on putting in. A rocket stove but I calculated the cost ov that as the same as putting in a hydronic (in floor) heating with a cast iron wood fired boiler. I've done a number of these systems and know that I can put one in for about $5-7 per sqr ft. That's a huge chunk of change. How much will a RMH cost to install? Ballpark?
I am doing all the labor myself and a couple of volunteers so labor makes up 0% of my costs.
I'd love to scrounge but here scrounging is just not like in the US. You go and ask someone to take down an old building for them and they'll start negotiating with you on how much you'll pay them for the privilidge!
Down in the big cities maybe, but not in the rurals!
Any one know some good books on Adobe, stucco, cob? Sites for newbs?
I'd like to get my estimated costs down to about $10 per sqr ft. That would be...life changing.
Why did you decide to go with a batch reactor other than a continuous flow reactor?
Your greenhouse stays that warm all winter? what are your outdoor temps like? If you have clear weather a simple solar collector should give you enough added BTUS to keep the reactor nice and toasty even in the winter and that would affect the greenhouse temps positively as well.
Brett, Sounds good. I have the Better Farms 2nd Biogas plant. Is it the Same as the UN plant?
I am planning, if I do settle on a batch design, to use this plan but to use the square 260 gal containers instead of 50 gal drums. I'm having a hard time projecting my digester.
Currently I use about 17,138 buts worth of propane per day.
It seems like I need to load the batch with 92% water and 8% solids (by weight). So i'll put in 176 lbs of feedstock (sawdust, straw, hay, manure) and that should give me a total of about 320,000 btus (1,818 btus per lb). Does this all lok right so far??
The problem I'm having is figuring out how much time will be needed. I'm looking at batch times differing from 30 days to 100 days!! At 30 days one cube (batch container) would give me about 10.667 btus per day. So with two cubes I could get over 20,000 btus worth of methane. BUT if my batch time needs to be 100 days then I would only be getting about 3,200 btus worth of methane per day. I could scale up to four cubes but even that would only give me 12,800 btus worth of methane per day. Sooooooo...What gives??
I really want to do methane. BUT the bad numbers look really bad and the good numbers look well, good! If it is a situation where I could get 80% of the methane in 40 days and then reload the batch and forget about the other 20%, that would be fine too. but, i'd like to know. Cause with my 80% model (if it is even realistic) I'd get about 256,000 btus in 40 days from one batch that gives me about 6,400 btus per day, so I could run 3-4 batches and that would give me my needed btu amount per day. I would start a new batch every 10 days. That is not that much work and would work well with my cleaning schedule.
Any thoughts?? I'd love to see photos once you've got them up.
I will use a parallel connected string of inter tubes as my collector and then run an underground pipe to my house. IF I can find the answers to my qs and IF those answers make me happy then I will do this and will also place photos.
How are you keeping the your batches warm? How many batches will be in your system?
I will be running a heat exchanger from a giant (70 cubic yard) compost pile to each cube batch and using my wood fired hot water heater I'll be putting in water that is hot so the heat exchanger only ever has to keep the batches warm. The batches will be situated under the hallway of my barn, between the stalls, and will be very well insulated and then reburied. So, should be good.
Hi All, I've been starting a lot of topics lately. I'm sorry if that is not too cool. Anyway, I just have q's and am searching for answers. So, here goes.
I want to build a methane digester in my barn to use bedding and manure from my goats and chickens. I use straw and sawdust as bedding and since goat poo is pretty dry (and small) I plan on feeding the digester with this bedding mix (sawdust, straw, droppings).
There is so much info on the web about bio digesters and some of it seems outright contradictory. So, I'm looking for some experienced advice.
I do not see how anything containing sawdust, stray or hay could be digested in a continuous flow digester because is will block the flow and or settle on the bottom (hay and straw block, sawdust settle). Some claim digesting woody material is IMPOSSIBLE, some clai it works WONDERFULLY. Some claim that undigested vegetable matter (hay) will take far too long, others say it takes a bit longer but produces considerably more gas.
I can get several large 1m3 (about 260 gal) square tanks (you know the kind on pallets in metal cages) for next to nothing. I was thinking of buying four of them in my barn (insulating them very well before burying them) and plumbing in a heat exchanger from a jean pain pile. I would fill one, seal it, hook it to my gas collectors. I would then wait 3 weeks and fill the next one and son so that in twelve weeks I'd have all of them flu and producing. Then I'd empty the first one and start over. Is there some reason this will not work?
Also, does vegetable mater (sawdust and straw) break down enough in 12 weeks to be pumped out with a sludge pump or will I need to shovel it out?
And what is a good, authoritative source of info on this topic. A book?
Yah, unfortunately harvesting trees would mean actually having a piece of property in the woods which seems like that is something the russian government just doesn't like. "Citizen, you must live on a half acre lot (MAX) inside town!"
I just ran the numbers, harvesting my own timber would bring the expense down by about $3 per sqr ft.
This has value for you guys since, with rare exceptions, building materials here are as expensive if not more expensive than state side. Plus you can scrounge!
I have nothing against scrounging, by the way. Just that the Russian society at large is not to the level of opulence that the US society is that people are often throwing out tons of good stuff. I've done some scrounging in the US (when I've been home on furlough) and it seems to me that in that land of fattened calves and suckling pigs, where the junk yards flow milk and honey, one could build for...maybe not nothing but VERY little!
Just an outsiders observation.
The problem in the US is permits, codes, zones, regs, etc!
Just judging from past experience, in our area when you need heat the most (Nov-Feb) the heat coming through those windows is very little compared to the heat going out. -40 outside tends to make a huge pull on the heat inside! That's as far as the windows go.
Aerated concrete blocks aren't all that good insulators (better than wood, worse than fiberglass) And I'd use a six inch block (standard exterior wall aerated concrete foam blocks are 12"). The main purpose for this is sound insulation. In my economic context, stud, fiberglass, sheet rook, mud, tape, plaster, paint walls are not cheap and they give more thermal insulation and less sound insulation! Brick is more expensive by a long shot. My design is a urt style house converted to wofati. The floor plan is like this...
I'll have a rocket mass heater in the living room (central octagon) area to keep the chill off and the outer ring should be sufficiently connected to the earth for adequate transfer of heat.
A normal house would cost a minimum of about $30-$40 to construct per sqr ft. So. But then I don't have to deal with all the permitting stuff (code, septic, building permits, etc)...yet.
When temperatures were consistently low I had a pretty solid 20 to 25 C degree lead on the outside temperature. However, it Never Got colder than -18 C (-0.4 F) in the greenhouse. Barn temperatures were always around zero C (freezing) or slightly above freezing.
I also have a root cellar underneath the greenhouse that is consistently a few degrees above freezing until late January when things got real cold (-40 C and F) after which it has been pretty consistently -2 C (28 F).
So some sample temperatures
2C 35.6F -17 C 1.4 F
-12C 10.4 F -35 C -31 F
-13C 8.6F -40 C - 40 F
Towards the end of the winter it seems the available heat in berm and earth around the greenhouse had been depleted because the temperature difference dropped.
-19C 2.2F -40 C -40 F
-12C 10.4F -32 C -25.6 F
These temperatures are for the inside of the greenhouse in the morning before dawn. This has allowed me to demonstrate that in order to heat the greenhouse I will need about half of the heat energy as I had previously thought necessary. So hopefully I'll be able to keep workable temperatures in the greenhouse using only 1 Jean Paine style pile.
Right now the greenhouse is not heating up as quickly as I had hoped. I think this is partially due to the ice build up on the inside (frozen condensation coming in from the barn. AND I think this is due to the thermal flywheel effect which worked so well in the fall is working against me here.
Some ideas that I'll probably implement in the next greenhouse/barn building. The hayloft does not do so well in keeping in the heat. Make the barn a true wofati structure by not having a hay loft above and simply burying the whole barn portion of the structure. Because the back of the greenhouse extends above the floor of the hay loft (or the ceiling of the barn), there is a whole section of greenhouse wall that is exposed to very cold temperatures with very little to no insulation. Bad design. By berming earth and using some insulation on this portion I think a LOT of heat loss could be avoided.
Also I need a steeper angle of glazing. Does any one have a definitive idea on what angle the glazing SHOULD be at?
I also need to work harder to berm thick to the corners. I also want to make some canvas "curtains" to put on the outside of the glazing from evening till morning to help keep heat in and remove them during the day to let the light in. I also should have built a cob wall between the greenhouse and the barn instead of just a board wall. This would provide a little better insulation for the barn as well as give the greenhouse some thermal mass that can be directly heated from the sun. All in all this project has functioned better than I hoped but the experience has shown me that it can function a LOT better IF designed somewhat differently. I hope to get a Jean Paine pile going this summer to use the Greenhouse this fall.
Those pictures were from the construction and then from this February, early.
These photos are from early March ( a few days ago).
I cleaned some snow off of the polycarbonate and It REALLY makes a difference. I also took some photos showing where the earth berm was not deep enough and where walls would have really benefited from just a few more feet of dirt or a PAHS umbrella. I also show here the problem with condensation that I did not count on at all. Having to scrape off layers of ice from the INSIDE of the greenhouse to let the sun in!!
Alright, Sorry everyone who asked for photos. I had some internet issues and then it took me a bit to figure how I was going to upload a decent amount of pics to the forum, but I think I go it figured out!!