There's very little heat in UV, compared to infrared.
I wouldn't pay extra for something with UV blockers, but I wouldn't go out of my way to avoid them either.
Solar cord wood kiln operation
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I wouldn't pay extra for something with UV blockers, but I wouldn't go out of my way to avoid them either.
Turd Ferguson
New Member
You've been running this for a couple years now- is there anything you've learned since this thread went dormant that you'd be willing to pass along? I am in a situation that presents the need for a solar kiln, and I'm trying to minimize my mistakes and get the best bang-for-the-buck given the circumstances. Any design/operational changes? Advice?
Thanks!
Thanks!
Woodsplitter67
Minister of Fire
It would be super helpful if you could tell me about the area your going to be set up in as well as how much wood you plan to try to dry as well as your timeframe of when your splitting
Turd Ferguson
New Member
Considering the expense involved, I'd like to try by designing this system for 1 cord of wood. Based on an 18" log length and stacking two rows (1 on each side of a 4x8' sheet of PT plywood), I get a height of roughly 64" tall.
My wood is currently in the 25-30% MC range. I'm finding it very difficult to burn in my Fire Chief FC1000 and I believe that the MC is having the largest effect on its ability to run unattended.
My long-term goal is, if this should prove effective, to build another, identical unit to be able to season a couple of cords every few months.
Woodsplitter67
Minister of Fire
The expence is minimal. You could set up a cheep one like i did to start with for like 75 bucks or less depending on what you already have on hand. You could easly do 1 or 2 cords this summer and have it plenty dry by the fall of 18. Also well below the 20% MC , not split smaller neather. You can get the larger splits down that far.
You can do 2 rows. I would start with 1 cord at a time, start at mid may and go to mid July put in a fresh cord and do mid july to October and your off and burning
I did my first kiln with 2 home depot wood racks and 6mil plastic. Took me and my son a couple of hours to put it together..
Turd Ferguson
New Member
I have a more immediate issue in the sense that I have wood right now that's 25-35% MC and need to get it down to 20% ASAP so my furnace will burn it. I was hoping this may be an interim solution with the wood I have on hand seasoning as fast as possible. Thoughts?
Woodsplitter67
Minister of Fire
Looks like you in mass.. thats north of me. I dont think that your really going to dry anything in the dead of winter with the current sun angel and the temps were having right now. A solar kiln is exactly that. A kiln that is run by the sun. Sun angle as well as duration is what drives the kiln.the kiln needs to heat.. ther needs to be enough time to get the temp up in the kiln to dry the wood.
Just noticed, sorry. When i build more i will probably duplicate my module number 6, i used the same plan for #7 and #8.
Its the last one i took an end shot of and posted dimensions.
I think in the future ill maybe make the last little stubs the ridge pole sits on a tiny bit longer and flip the ridge pole over so the pvc elbows are under the ridge pole rather than above.
I am thinking about replacing the plastic sheeting with corrugated clear, at least on the sunny side.
Future builds ill likely use 2x6 for the floor framing. 2x4 is barely adequate, but it is adequate.
Its the last one i took an end shot of and posted dimensions.
I think in the future ill maybe make the last little stubs the ridge pole sits on a tiny bit longer and flip the ridge pole over so the pvc elbows are under the ridge pole rather than above.
I am thinking about replacing the plastic sheeting with corrugated clear, at least on the sunny side.
Future builds ill likely use 2x6 for the floor framing. 2x4 is barely adequate, but it is adequate.
I do agree with @Woodsplitter67 , getting enough solar gain to measurably dry out damp wood in the winter months is asking a lot.
Turd Ferguson
New Member
Thank you for your replies. I'm noticing that once I have my wood indoors it is drying out a little better. I am much closer to 20% now than I was several weeks ago.
What is your opinion of using the PVC stake poles versus wrapping the stack with sheeting and shrink wrap? Is it worth it? I'm sure if condensation accumulates on the sheeting and can't be vented, it'll make its way onto the wood without the poles providing a barrier. However, in either of yours' experiences, have you had this issue before?
What is your opinion of using the PVC stake poles versus wrapping the stack with sheeting and shrink wrap? Is it worth it? I'm sure if condensation accumulates on the sheeting and can't be vented, it'll make its way onto the wood without the poles providing a barrier. However, in either of yours' experiences, have you had this issue before?
Woodsplitter spent a lot less money than me for his setup, got results just as good, so bang for buck advantage @Woodsplitter67 .
I very very rarely have liquid condensate running down the inside surface of my kilns. I have seen it exactly one time. With that one exception, the water comes out of my wood as a vapor and gets pumped out without condensing -though I did design and build for condensate on the inside of the sheeting to drip off the edge of the plastic sheet out on the lawn.
There is a user who just used shrink wrap on palletted stacks of splits with good results. Forgot user ID sorry, I think he has posted in this thread.
I very very rarely have liquid condensate running down the inside surface of my kilns. I have seen it exactly one time. With that one exception, the water comes out of my wood as a vapor and gets pumped out without condensing -though I did design and build for condensate on the inside of the sheeting to drip off the edge of the plastic sheet out on the lawn.
There is a user who just used shrink wrap on palletted stacks of splits with good results. Forgot user ID sorry, I think he has posted in this thread.
Turd Ferguson
New Member
It wasn't my suspicion that the poles helped a great deal, maybe except for very high humidity days. But we don't get those very often here and the additional savings on this proof of concept would be a great help.
@Woodsplitter67 What does/did the top of your kiln look like? Just a 2x4 running the length of the pile to keep the sheeting raised? I think that's the only photo you didn't post that would be super helpful. Also, were you using some sort of vapor barrier on the bottom of your piles to prevent ground moisture from coming up?
I may split some rounds I've had for a few months now and stack them into a prototype kiln to see what happens. Worst case it's c/s/s for next year. A cord will fit nicely onto two pallets at a reasonable height.
Iirc woodsplitters kiln had open slats at the floor. I am on an ancient flood plain about 20 vertical feet above the current river surface, lots of groundwater at my address.
Turd Ferguson
New Member
Maybe I'll do a little experiment. Do one with, one without, and see what happens. I think the first priority is getting the temperature up in the kiln, then controlling ventilation. Without temperature elevation, there's no point to ventilation because the air won't be drawing any water out of the wood.
I experimented when i was using pallets and tarps before the kilns. I put a layer of plastic on some of the pallets before the green splits went on, then tarped above like the rest.
It made a difference at my house, but if you are on a thick gravel deposit it might not make any difference.
It made a difference at my house, but if you are on a thick gravel deposit it might not make any difference.
Woodsplitter67
Minister of Fire
I used some 1x3 for the roof. I had 1 2x4 on each end horizontal and attached the 1x3 to make the top portion of the roof.. draped the pladtic over it and wraped the bottom with contractors stretch wrap to hold the plastic in place. The wood was put in regular wood racks stacked Kris Kross and the wood racks were elevated up off the ground with pavers. The 2 sides had 5 inch round holes cut in for vents and 1 small vent in the middle of the roof
Chas0218
Minister of Fire
Why clear plastic instead of black wouldn't the black get it hotter for longer? If you are just taking measurements anyway I don't see how the clear would benefit? I understand the effects of the sunlight on the wood but I would think that the heat is more desirable than direct sunlight when kiln drying wood. I think you would see your temps level throughout the entire shelter and have less hot spots at one end than another.
I plan on building a wood shed with bays holding a around 1.75 cord using all black tin for the roof and sides I think it should heat the wood in the summer nicely with a clear sheet of plastic across the front and open top.
I plan on building a wood shed with bays holding a around 1.75 cord using all black tin for the roof and sides I think it should heat the wood in the summer nicely with a clear sheet of plastic across the front and open top.
Ashful
Minister of Fire
I think the best answer is "it depends." Mostly on where you are and what your local conditions are like.
When I was seasoning on Pallets with just sheet over the top, open sides, it seemed like maybe advantage black plastic. It wasn't much different, but if there was a difference the black was a little quicker, at my place.
At my address, 64 degrees north latitude, I have 18+ hours of direct sunlight on my stacks for a couple months, very few addresses in the lower 48 have that.
If someone wants to dry black plastic on kiln, I say go for it. Who knows?
I also suggest trying both and dialing your system in for your conditions. There might be another guy a mile down the road from you get different results because of a different tree line or different subsoil.
I got to here by starting with pallets on the ground, then pallets on cinderblocks, then some pallets with a floor layer of scrap plastic, I spent a lot of time figuring out what works on my land with my conditions.
Chas0218
Minister of Fire
I understand was just curious, as of right now I don't have a lot of time to season my green wood before I have to burn it. I would like to get a few years ahead but that would mean cutting 18 cord worth of wood this year splitting and stacking then another 6 cord next year and so on. I managed to get around 9 cord CSS this year so hoping to get another 9 CSS this winter/following season.
Woodsplitter67
Minister of Fire
Ashful
Minister of Fire
He ain’t far from me, and this is my local forecast (and summary of this entire summer):
Easy Livin’ 3000
Minister of Fire
Well, except for the handful of days that were oppressively humid and hot. My least favorite spring and summer in my recollection. If winter is cold with this kind of precipitation, we are in for a workout.
Alright now, look here. On my lot I can, and have, run a line of pallets 64 feet long, stacked 8 cords on there in two parallel stacks, top covered with plastic and gotten to 16% in one season (softwood).
There are some disadvantages to that.
1. dealing with snow on top of the tarps when going outdoors for wood.
2. getting my boot stuck in a pallet space when getting wood from the stack on the far side of the pallet
3. Blown snow getting all up in my splits that aren't side covered
4. Having to go out there every time it rains to get the rain out of the center gutter created in the plastic by the weight of the rainfall on the stacks.
5. It looks kinda of trailerpark / ghetto
6. I had to restack at least part of the pile every year. One year three times, that year I watched four cords fall in about 15 seconds, I was out there looking when it let go. Sounded like an enormous bowling alley.
I did try a few top covering strategies. I used some plywood scraps to bridge the two stacks under the plastic, worked good but was a Pain in the place the sun doesn't shine once it had snow cover on it. I tried covering the two parallel stacks individually, but the ends to the inside that got plenty of rain and minimal sun, I bought a lot of bio-logs that year because the inside ends were pretty wet.
So with this system, I laugh at rain, it falls off. For blowing snow, I laugh, I am side covered. No stuck boots, plywood floors. Looks kinda NASA, still not suburban, but not ghetto. No restacking yet, my longest horizontal run is 7 feet 5 inches. I laugh at snow accumulation, falls off.
The unproven thing still, how many crops or seatings or loads per year. I feel pretty good that I could season 8 cords of spruce in one summer, four cords at a time. I don't have a woodshed that will hold four seasoned cords, and I don't have a good place to put one. I was hoping to see how fast I could get the spring load dry this summer, but life got in the way.
When I load these things, I just drop the splits in . I am at too high a volume to spend time "stacking".
There are some disadvantages to that.
1. dealing with snow on top of the tarps when going outdoors for wood.
2. getting my boot stuck in a pallet space when getting wood from the stack on the far side of the pallet
3. Blown snow getting all up in my splits that aren't side covered
4. Having to go out there every time it rains to get the rain out of the center gutter created in the plastic by the weight of the rainfall on the stacks.
5. It looks kinda of trailerpark / ghetto
6. I had to restack at least part of the pile every year. One year three times, that year I watched four cords fall in about 15 seconds, I was out there looking when it let go. Sounded like an enormous bowling alley.
I did try a few top covering strategies. I used some plywood scraps to bridge the two stacks under the plastic, worked good but was a Pain in the place the sun doesn't shine once it had snow cover on it. I tried covering the two parallel stacks individually, but the ends to the inside that got plenty of rain and minimal sun, I bought a lot of bio-logs that year because the inside ends were pretty wet.
So with this system, I laugh at rain, it falls off. For blowing snow, I laugh, I am side covered. No stuck boots, plywood floors. Looks kinda NASA, still not suburban, but not ghetto. No restacking yet, my longest horizontal run is 7 feet 5 inches. I laugh at snow accumulation, falls off.
The unproven thing still, how many crops or seatings or loads per year. I feel pretty good that I could season 8 cords of spruce in one summer, four cords at a time. I don't have a woodshed that will hold four seasoned cords, and I don't have a good place to put one. I was hoping to see how fast I could get the spring load dry this summer, but life got in the way.
When I load these things, I just drop the splits in . I am at too high a volume to spend time "stacking".
Chas0218
Minister of Fire
I agree, my stacks look trailer park esk. They have a pallet on the bottom one on top attached using 2x4's on corners and middles. The tops get plastic pallet sheet covers until I throw some junk tin or the like over top. I scavenged some fiberglass panels someone threw away at the dump to cover the stacks next. On average I get about .50 cords per each "house" my plan is to use the same concept but be able to move a "house" to and from my deck using the tractor and forks and being able to rotate stacks within the wood shed for better drying. Not sure if you can visualize what I talking about but basically small 4'x4'x'4 cubes of firewood that I can move around on pallets.
