Progammable thermostat
 

Okay, I don't usually give glowing reviews about products, but I bought
a progammable thermostat that is designed to plug into a standard
outlet, and power a 1500 watt space heater or window air conditioning
unit. Actually I bought two of them, one for each heater. It has sure
made my life simpler so far this winter.

http://midwestorchids.com/orchid-growing-c1-0.html