I'm trying to figure out what is the best approach to air-con home automation and temperature settings while keeping the electricity costs down. I have added foam weather stripping to all the windows and doors. There is reflective tint on the windows and I have blackout shades/curtains on the way. 2HP split inverter air-con in use. Spoiler: Home Automation Description My current automation setup looks like this: The thinking behind this: 0700: Air-con turns on @25°C (usually when outside temperature hits 27°, the sun starts to hit with some force and the inside temperature starts to rise) 1700: Temperature adjusts to 27°C, floor fan kicks on. (outside temperature usually drops to or below 27° at this time and the sun isn't beating down directly on the house, but without the air-con the temperature will creep up.) 2000: Air-con turns off and windows are open. (Outside temperature is usually 26° or below and a floor fan gets the job done) Leaving the house between 0700-2000: temperature set to 28°. Returning home sets temperature to 25°, 27° or does nothing depending on the time. It takes about 15 to 20 minutes to get the house to the desired temperature during the day. With my current setup I'm expecting an electrical bill between P3500 to P4500. My question is concerning what should be done when I leave the house: is it better (meaning cheaper) to have the temperature set to 27° or 28° to keep the humidity down and walls/floor cool or to just turn it off when go. Today I tried turning it off while I was away for a few hours. The inside temperature got up to 30°. It took about 40 minutes running at full blast to get the house back down to 25° (about twice as long as it takes when the temperature is set to 27-28° while I'm gone). I suspect that keeping it running, but at a higher temperature, may be the cheaper option but I'm not sure. If there is any other suggestions for keeping costs down they would certainly be welcome.