Energy Consumption Poll (my shop)

Yeap, my big swamp cooler does the whole house 20+ deg cooler than outside. Ave humidity is 30 - 40 % here, so it works properly.

Add thermo control exhaust fan under eve peak, both ends of shop.

My vote, when you and the dog are gone, leave a/c off. Maybe install some sort of controllable lever operated vent in the ceiling and add some cross flow like an exhaust fan(s) or vents in the eves.
This way you can bring in regular hot outside air and exhaust the 115 - 135 deg heat from the attic or top area which will save you energy big time.

Then shut off the exhaust fan (unless you have a drop ceiling or separation level, then you should just leave it thermo controlled at 85 deg shut off) and put the a/c on 80 when the dog is there (with a circulation fan(s) as mentioned) and put it on 78 when you are there.

You will probably shi* when you see your bill from keeping it 70 deg in there.
I would, and have.
.