Our usage is down 9.9%. That isn’t amazing, what is this is an Airbnb rental. We don’t control the usage of electricity at all. The cost reductions do not reflect the 12% higher occupancy in the highest energy consumption months.
So how did it happen? Sense, combined with some home automation, helped me identify what caused the consumption:
They included a mis-wired thermostat which only allowed for resistance heat vice heat pump heat.
I saw some significant temperature swings by some guests using the thermostat to suit their mood. Over 100 temp changes in a month is not that rare. Sleep at 65 and awake to 74 for example. Over three degrees calls for heat increase automatically turned on resistance heat, vice the heat pump. I was able to remotely disable that. I don’t change the temp remotely but there certainly have been times when I have tempted to. I have disabled the fan always on (vice automatic) I believe guests aren’t familiar with the thermostat or the effects of leaving the HVAC fan on all the time. In a Florida home with duct work in a 130 degree attic leaving the fan on with even a 5% air leak brings in constant hot air to a cooled home.
I determined that guests were leaving the slider open to a covered porch, enclosed with single pane glass to cool it off and then leave for the day. I wrote an automation IFTT procedure to shut off the AC if the slider was left open, similar to hotel chains or commercial buildings.
I found the large bank of florescent lights (240 watts) was turned on in the garage and left on after they opened the overhead door to the bright outdoors. That made no sense as the garage door has a light, like any garage door opener does. I installed an occupancy switch to shut the lights off when vacant 20 minutes.
I installed an efficient attic fan, replacing an inefficient big box store model.
And finally I installed smart outlet to shut off the cable boxes when the home is unoccupied, this has not paid for itself but it gives me satisfaction.