This is for indoor use to heat anywhere from 400 to 1000 square feet
Double This smoke detector has a 15ma current draw when Alarming, yet only draws 70uA micro amps when in standby. 1000uA 1mA In other words this smoke detector draws 1/215th the power in standby as it does when alarming. EDIT: No mention of specific current draws in datasheet. However the unit has a green LED to indicate power is on. LED's will draw 10-15ma. The red led flashes, this is most likely when the unit wakes itself up to test the air.I believe that this unit would draw 20ma in normal operation and mainly to light the LED. The full 80mA would be when it was sounding an alarm. During battery backup operation the current draw would be far less as the Green LED would be off. I would expect to see micro amp current flow to conserve the battery. Based on this information your expected operating costs would be 1/5th of what you calculated assuming a 15ma current draw.
1. Probably something along the lines of 'sh*t sh*t sh*t sh*t sh*t sh*t sh*t sh*t sh*t sh*t sh*t sh*t sh*t sh*t' 2. Unlikely. They would feel as if they were floating in a very strong wind so they might not have been able to breathe easily, but the fall would be too short for them to pass out through lack of oxygen. It is possible a few of them fainted through sheer terror but we'll never know. 3. Instantaneously fatal, massive traumatic damage. They would have been falling at 100mph+ by the time they hit the ground, use your imagination.
