Hi:  You can find it advertised inside the cover of almost any recent
copy of ABJ.
 
At the price, it will take a long time to pay off, even with better honey
prices.
 
I haven't seen any hard data about whether this thing actually increases
honey yields.
 
Seems to me that conditions inside the hive will vary a lot from
according to time of year and geographic region.
 
For example, Maryland is sure different from Montana.  I have seen water
sheet down the inside of hive walls in Missoula, MT and Seattle, WA during the
spring rainy season, but nothing like the conditions inside confined
hives in Maryland when the temperature and relative humidity exceed 90%.
 
Cooling down a hive in hot climates can be simply accomplished by tipping
up a corner of the lid, although this probably works better with flat
lids than with telescoping lids.
 
John Harbo has published some data that suggests that warm hive interiors
may help suppress mites.  We have some data that seems to indicate that
colonies subjected to fungal-based pesticides are somewhat protected by
the high core temperature (brood nest) of a healthy colony.  In fact,
colonies exposed to fungal pathogens may actually increase their
temperature a degree or two (evidence still a bit shakey).
 
Granted, one can heat prostrate a colony.  But does it take more energy
to cool down or to heat up a colony by a degree or two?
 
Thus, I for one would like to see the data to back up the claims for this
solar ventilation unit.  Perhaps the manufacturer could post it for all
of us.
 
Jerry J. Bromenshenk
The University of Montana-Missoula
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