Help me build a solar fan set up to kiln dry wood

We recently got a wood fired pizza oven. Kiln dried wood is best to use and I’m finding wood out of our log store (used for woodburner usually) isn’t quite dry enough.

I’m thinking if i could rig up a small/cheap solar panel attached to a small fan I could create a very small solar powered kiln to dry small quantities of wood for the oven either inside or just next to our greenhouse. Would be great is the fan came on whenever there was enough sun to power it.

Anyone know what i need to run a fan direct off a small solar panel? I’d like to avoid scope creep (batteries, charge controllers, inverters etc).

There are a few solar fan kits on Amazon but thinking i might get something better diy’d with a small 2nd hand panel and cheap fan…

Any tips/advice on where to start?

Bit confused about the kiln/fan confusion.
Are you planning to heat the ( naturally moist UK) air before blowing it over the wood?

If not, what are you expecting to happen?

Mentioning your greenhouse …. I’d forget about fans and solar panels – if there’s enough sun to turn the fan theres plenty of solar energy and heat to dry wood more directly

Have a look at various designs of ‘solar oven’ – reflectors inside a greenhouse or some sort of closh to collect and concentrate heat. I’ve done projects with kids where we’ve pasteurised water in 20 minutes or October sun using tinfoil and a cardboard box

Bit confused about the kiln/fan confusion.
Are you planning to heat the ( naturally moist UK) air before blowing it over the wood?

from the reading i’ve done greenhouses are generally full of moist air (especially iin summer with watering etc). my plan was to power a small fan located next to the small stack of wood to push the air through it and speed up the drying. youtube has examples of woodworkers drying wood in diy greenhouses with large fans running to push the moist air out. i was thinking something similar on a smaller scale.

Could you not just dry small quantities in your oven?

Edit: your kitchen oven obviously, assuming you have one and no-one else objects?

Could you not just dry small quantities in your oven?

Well i popped some in the oven last night after we’d finished cooking pizza and the temp had dropped a bit. It seems to have dried the logs nicely (waiting for my moisture meter to arrive).

I’m 1/2 scottish so i’m trying to find a free way to build up a bit of a stash of kiln dried wood and i’m not sure the wife would be keen on my bringing wheel barrows of logs into the kitchen :-)

TBH I think a ‘tiny black shed’ with ventilation coming up from ground level and exiting under the roof will do just fine. Convection on the warm days will keep the air moving as the warm (moist) air exits the top and draws cool dry air in at the bottom. You’d only need a fan if you wanted to assure a consistent dry for timber you intend to work. Stuff for burning just needs to get down to a certain moisture level. The best thing you can do once dry is move some indoors to keep it that way. You can dry it until the cows come home but as soon as you move it out of the kiln it will absorb the moisture from the air again.

What moisture content percentage are you looking for.

i think airdried is about 12% on average, up to 20%. If its for a pizza oven I also think thats ok @20%, so just airdrying should be fine.
Remember to keep timber protected from rain.

Just keep the rain off. After a while it gets dry with no effort on your part. I burn last years wood. Its that simple.

i’m aiming for ~10-12%. Typically i reckon my wood int he woodstore is nearer ~20%…hence i’m looking to further dry small quantities for the oven.

Anything i do ‘kiln dry’ will be stored in the garage to avoid it getting ‘wet’ again!

As a start do you think if i got a large clear plastic storage crate/box and put two holes in it (one near the bottom on one end and one near the top at the other) and put that in my greenhouse do you think it would work?

We dry wood overnight in the pizza oven, as you’ve done – it makes a huge difference.
I’ve dried freshly cut fig branches (2 to 3″ thick) this way, and they’ve burnt well the next evening.
If the wood was reasonably seasoned before you dry it in the oven, you can virtually light it with a match.
Easier than building a separate kiln.

What’s the end goal. Kiln dried wood or wood that is useful.

If your greenhouse air is moist….what’s blowing it over the logs hoping to achieve ?

Kiln dried is marketing for quickly processed wood -saves them having to store it in well ventilated dry areas for long periods and ensures that their product is uniform in large quantities.

Space costs but really unless your felling your own trees and want to burn them next week as oppose to just letting time do it’s thing it’s overthinking the situation.

Why not just keep a stash inside. A week indoors will dry it out that extra bit.

I’ve dried the next burn’s wood in the oven after a pizza session before. Need to remember not to close the door to the oven till the temperature has dropped a lot or the wood won’t be there when.you come.back 😆 (rooky mistake).

I’ve dried the next burn’s wood in the oven after a pizza session before. Need to remember not to close the door to the oven till the temperature has dropped a lot or the wood won’t be there when.you come.back 😆 (rooky mistake).

Haha…i did think about that possibility when i put some inside last night. Tahnksfully is was still there this morning!

Why not just keep a stash inside. A week indoors will dry it out that extra bit.

A while back I found a load of Longhorn Beetles in the living room that had emerged form the wood in the log basket. That kind of put me off keeping lots of wood in the house if it can be avoided.

If your greenhouse air is moist….what’s blowing it over the logs hoping to achieve ?

I was thinking i could put the fan near the louvre vent to help pull in dryer cooler air form outside to blow through the wood.

Kiln dried is marketing for quickly processed wood -saves them having to store it in well ventilated dry areas for long periods

Agreed. The guy i bought the kiln dried oak off supplies a few local pizza restaurants. It is oak offcuts from his saw mill. He dries them (quickly) in a poly tunnel which is open both ends. He reckons he can get them down to ~10% in a matter of a few weeks. I”m essentially trying to replicate what he does on a tiny scale.

poly tunnel which is open both ends. He reckons

Is he also trying to recreate a humid growing environment at the same time ? A polytunel open at both ends is a brilliant way to dry wood. Huge volume of airpassing through being constantly changed out.

It ain’t kiln dried though

Polytunnel FTW, possibly overkill for a pizza oven though.
They’re is a natural version of this fan you’re after… It’s called “the wind”, free to use and doesn’t stop when the sun goes down.

Just cover some logs (ideally with something to allow the sun though) and let the wind blow through them.