Hey mate. That heliostat surely looks interesting.
I'm not really qualified to help you much, but from my few years of experience here in Perth, where we don't even have the bugs you have over there, I found that hives perform better in full sun. I was going to say that you can always put shade over hives if you want to, but can't put sun on a shady hive.
Well I'm wrong, and I bet that will work quite well if you have no other options, and you can live with a large shiny disc in your back yard. But will it reflect much heat in winter, or just light?