tower hive system

[Dange]

I was pondering different hive ideas when i came across the tower hive system.  It is two colonies side by side with queen excluders on top. Then there is supers placed on top of the hive bodies so that the two different colonies share the supers. I cant post pics yet but here is a link.http://ento.psu.edu/pollinators/publications/twoQueesn  Has anyone done this and does it work well? 

[wildbeekeeper]

it takes advantage of a two queen system - you have two queens producing brood and a combined workforces that can potentially lead to more honey bring brought in to that hive.  Its not commonly used as far as I am aware.

[merince]

It is not commonly used because while it increases honey production, the gains are not enough to offset the management complexities.

Pros:
You double the honey yield (but it is approximately the same as what each colony would get on its own)

Cons:
If you lose one of the queens, you will have a hard time getting her replaced as the workers will not start cells due to the other queen's pheromones. They will also kill a queen in a cage as they already have an active one.
If the queens are not "equal", the bees will drift towards the more "attractive one"

[Vance G]

There was a real detailed description of how a gentleman was doing this in the early seventies.  It doesn't seem to catch on.  That is instructive I think.

[D Coates]

I meant to try this Spring but life got in the way.  I personally know of no one who's tried it but it intrigued me enough to want to try it for my own knowledge.  I've heard claims that it produces more than what the 2 strong hives would produce on their own, don't know how except the enormous workforce supposedly works more effectively.  All things being equal, a full strength hive will produce substantially more honey than a 3/4 strength hive.  Following that thinking a double strength workforce would be more than double efficient.  This is all conjecture though.