Here is interesting Israelian research .
http://www.beekeeping.com/articles/us/solar_heating.htmIt tells, that in USA climate insulated hives have big advantage. Heating is really comlex, but it tells that makes good for winter brooding.
I you use insulated boxes, your nucs will develope much more guickly and you can get honey first year.
This forum does not let me in any more

, but greetings to you.
DONT INVENT PROBLEMS FROM NOTHING!
Finman.