Seeking Great Cool Runnin' SS Amp...

If 100 wpc will fill the bill, McCormack DNA0.5 Rev A+ would be at the bottom end of your range, used, or you could get a DLX for about $700, and upgrade for about $750 to $1200.00, depending on what you want.

You might consider the cool running Consonance amps from Opera Audio. These received rave reviews and much attention at the recent Consumer Electronics Show.The 80 watt version will work nicely but if you listen at loud levels the 100 watt amp is a safer bet with your 86 db sensitive Proacs. The Consonance amps are similar to your Proacs in that they provide good detail, clarity and excellent soundstaging.They are a great mix with tube preamps.I understand your energy concerns as I also live in Arizona. Using an excellent power cord such as the Sahuaro Audio will actually reduce your amp temperature 6 to 12 degrees. Another suggestion is to run an overhead ceiling fan on low to add cooling. This should not degrade your sound quality much if at all. All of these products are in the middle to lower end of your price range. Overall, you will find the Consonance amps to be much more natural and musically involving than many of the amps mentioned.You can contact me for more information.
AudioLon

i have the Odyssey monoblock amps. I leave them on all the time and they are very cool to the touch, even at loud volumes. great pair of amps. I prefer these to the mcintosh amps i have owned, and to the classe, plinius, sim audio, etc... that i auditioned.

Jeff Rowland model 10 runs cool .

The digital amps run the coolist, Spectron, PS Audio, Bel Canto, etc.