Uses 0.5kW of power with a cooling capacity of 2.5kW.
Can be controlled remotely over the internet.
Approximately $800 + installation.
I'd spend the extra $1k for solar plus what ever it takes to insulate the observatory
then just set it to keep the scope below 17C
Problem solved.
http://www.samsung.com/au/air-condit...9FSSSBWK1.html