Well, one thing is for sure. If this solar kiln catches on, everyone that knows the members of FHC will surely be thinking..."They're the neatest bunch of guys when it comes to firewood stacks!"
The RH inside the kiln and ambient are identical this morning. We have a mass of really humid air in front of that tropical storm here. First time I have seen this happen. Although in absolute terms there is more water vapor in the air within because the temperature is 5 degrees higher. . Getting lots of graphs and data out of this thing otherwise. Nothing too surprising. Humidity within is almost the exact opposite of the temperature. And you can tell sunny days from overcast/cloudy days on the longer term graphs. Kiln temp/RH Sunny daytime temperature peaks are about 30 degrees over ambient, measured under a cookie on the top of the wood within the kiln. Ambient Temp I suppose I will eventually see a real downward trend on the RH monthly graph, but not yet. Its nightly high did drop a few points during the first week but has since settled and I did open it up and adjust the placement of the sensor which is marked on the graph last Saturday where the RH dropped radically. (I put in a PVC frame to hold the plastic and I put a cookie over the sensor instead of using the short side of the 2x that was previously acting as the ridge pole because I thought the sun was catching it.) Right now the RH stays pretty high unless the sun is on it and moisture continues to condense and drip out. When the sun is on it the dew point climbs, meaning there is an uptake in the absolute amount of water vapor trapped within. Makes me thing the kiln is working at its capacity, whatever that might be.
Great info! Always neat to see empirical data support various physical laws & principles that we have been taught. The relationship between temp & RH graphs is textbook. Looking forward to upcoming data on RH & temp trends. This info is so much better than my occasional "snapshot" temps that I get. Thank you!
So Paul, you'll need to explain how you've managed to condense beer from firewood. Inquiring minds need to know.
Great post Paul bunion ! Lots of data there, interested in seeing the end results and maybe a connected plot over the length of the experiment... Goodyear stuff, man
Not to be a fuddy duddy but people have been doing this for a long time, plenty of info on the net for results and the way they were built.
Now, by one point, the Kiln has a lower RH than outside. Today would be the first summer like day here as far as humidity goes. The past few weeks have been warm, but very dry with daytime RH in the low 20s.
I think you'll begin to see lots of variety in those two as summertime ambient r.h. fluctuates. Inside r.h. should stay relatively predictable. My hypothesis, anyway.
Some of my solar kilns seem to behave like terrariums. They are wrapped tight but do have open bottoms. After several weeks now there is still large amounts of condensation. I am concerned that the moisture cycles between evaporation & condensation. So I decided to vent 5 of my pallets with a pair of 2x5 inch vents.I will compare to 5 other non vented pallets sitting next to these. All pallets green Mulberry from same tree. Almost felt like steam coming out. Temps inside the vented pallets run about 5-8 degrees cooler than comparable no vented. Ambient temp today 81 degrees. Couple of internal readings... Am getting a 30 degree gain on some stacks, wonder if it will maintain that gain when it hits 100 here in Nebraska?
It does to a certain extent. My humidity probe shows it. Just as the sun hit it this morning it went from 88% to 92%. Kiln It was quite high all day yesterday but even in the high 80's it was less than ambient air, as it was cloudy and rained Ambient
I would think yer picking up more ground moisture than a bottom sheet with weep holes... My $.02. I say think about it this way, brenndatomu - a solar collecter for water heating typically has a clear surface, with the backing underneath the piping being black, there's more solar gain in this situation.... But, alas- maybe try a stack next to one of these types for comparison And since I've missed the chance to say welcome to the club... Hello! Yer at the best place for comraderie, learning, and a good ol' time! What took u so long?
Hmmm, interesting. Thanks! Well, I've been hanging out over on those other two "firewood nut" forums for quite a while, and lurking here a bit too, but between the one site crashing or getting "buggy" every 5 minutes, and very little traffic on the other forum here lately, I just decided to go ahead and jump in here.
I never did get a solar kiln rolling this year. Pretty much all the wood I have cut for 15/16 will either be dry just from being split from being quick drying species, or were already dead standing or were down before hand. I suppose I could still try one out, but for next year's wood, it seems pointless for me. The sugar maple I split that was long dead was like 12% mc. Maybe next year?
Hello All! After seeing Deacon's kilns of mulberry, which are exactly as mine are, and Paul Bunion's tech. temp. and humidity graphs I had to FINALLY join up. I've been a lurker for quite some time and couldn't stay out any longer. Thanks to you Paul for posting up the graphs! Very interesting stuff. Please keep us all posted. Deacon, I'm curious to keep track of your results also! Geographically, our weather is somewhat similar. Anxious to see how your stacks are doing in comparison with mine! I'll try to figure out how to get picks up in the next couple days.
Hey, Flatlander Pete nice to meet ya, glad you're finally on board! You can use the "Upload a File" button next to "Post Reply" or attach it/them from the tab located up there above where you're entering yer post- I use the upload button, thumbnail size, after emailing myself pics from my phone. I'm not smart enough to post a pic straight from my phone....