Solar powered cooling experiment

As it is winter here in Australia and the shortest day I can do an update of my solar powered fan hot air extractor built into a migratory lid.
I have removed the lid for the winter, time to repaint the lid but from memory I fitted the solar roof on in the heat last January and that hive a noticeable reduction in fanning and bearding of that hive during the extreme heat wave of Summer when maximum temperature were being recorded all over Australia, as well as here. Ok, it wasn’t a scientific test as it was one hive among twenty at my apiary but it didn’t have as much fanning during the heat of the days. The fan is controlled by temperature under the roof.
I noted all the warning from those warning me that the bees would be angry because of fan vibration, electrical fields, the sound of the fan motor to name a few but in use I saw nothing to validate those theories.
So was it a benefit to the colony, well it certainly did no harm to the colony but nor did I take more honey from that hive than the rest, if that is a indicator, but no two hives produced the same amount of honey either. It wasn’t the biggest honey producer but it was in the upper producing hives.
Will I make more solar lids? On nights I am bored and happy to tinker I might so I can get more data. But I doubt it will become a priority on my “To Do List”…
Just a few pics.

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That’s interesting as I was wondering about ventilation of the hives this year. I pulled out the core flute board thinking perhaps the bees would cap the honey faster with more ventilation. I didn’t think it aided in honey capping. But it did aid in the bees going under the hive. So I put the bottom core flutes back.

Does it work like a bathroom fan sucking hot air out?

It is a ‘pusher fan’ in that it sucks the air in the roof and blows it out of the roof thru a 35mm hole with a piece of metal flyscreen on each side of the fan.
Cheers

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The solar power roof has been on the hive for 18 months now so I thought it time to update on the project.
In my sub-tropical climate in my Winter there isn’t an issue there is no need for insulating the hive and the hive visually is not effected by the blowing out of the hotter air in the roof area above the super.
In the really warm weather there is no bearding or fanning seen even on an evening, but of course the fan only operates when there is enough sunshine to power the solar powered fan, but it works to within 30 minutes of sunset.
I was warned that the bees would block up the mesh covering the fan but after 18 months it is totally clear of any propolis or wax, so I guess the bees are not upset by the extra ventilation it makes to the hive. The colony is as calm as any of the other hives.
Have I made more of them? No, it is not cost effective but because of the positive results I have began working my way thru my hive fitting the same plastic that used to be fitted to kitchen cupboards when I was young, they are still available from any hardware store like Bunning’s and Mitre10 in Australia. The vent fits a 38mm hole and I fit them at each end of the roof. So doing that is worth thinking about in a warm climate. It frees up more bees from fanning at the hive entrance for foraging for a possibly better honey yield.
Cheers
Cheers

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Thanks Peter for an update on this. This applies to my climate so I bookmarked it.

In the bee’s native Europe, I often saw beehives completely exposed in trees or outdoor structures like the one @Semaphore found recently with maximum ventilation.

They are very adaptable.

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thanks for the update Peter. I read once that bees can cope with cold far better than they can cope with damp. That makes a lot of sense to me. High humidity in the hive, dripping condensation, etc- would create an environment where fungus and mold can take a hold. However if everything is dry- it seems far more healthy to me. The bees may have to eat more honey to stay warm though- so there is a chance it would be less productive- unless the health benefits outweigh the heating requirements: More happier healthier bees could produce more honey than in a damp hive.

I know people like jeff see little need for added ventilation, screened bottoms, etc- but I do know that here in SA- in winter especially dampness can be an issue. Hives can come out of winter with mold on the tops of the frames- and water dripping from the roof down onto the brood (unless you have hive-mats like I do- but still it can pool n the mat.

I would be interested to see over time if your solar powered fan hive starts to show any marked improvement over the other passively ventilated hives.

I agree with you about humidity being an issue often not considered Jack. The solar cooling got me experimenting with fitting cupboard vents and found lees fanning and bearding in my hot weather than roofs with no vents. I have now fitted 3 vents at each end of the roof on a few hives to see if that is either better or worse for the bees. I fit hive mats on seeing them at @JeffH 's hives and that is a definite benefit.
Maybe I am over simplifying my thinking but I figure if if the colony is too hot then bees that can be out foraging are staying in the hive to cool it.
Have you done anything with the honey warming chest Jack?
Cheers

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cabinet hasn’t progressed- but as it is rainy today I might get onto that later…

Hivemats are 100% definite MUST have. Not only do they prevent condensation dripping down onto the brood- I think they also would help the bees maintain brood temps to their liking- as a hive mat means the combs are arranged as they would be in a natural hive, where bees cannot walk up and over the top of each comb. But the number one reason for hive mats is that they stop the bees ever attaching the combs to the roof. If the bees ever fill the lid with honey- it will all be nicely capped and ready to remove. Without a hive mat when you take the lid off the frames in the brood can lift up with it- the comb breaks- honey goes everywhere and removing it while bees are trying to lick it all up is a pain.

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