I don't understand how hours run equates to your calculation unless it was always pulling 2,7 kW. Is this some 30 year old setup that doesn't have an inverter-d

I don't understand how hours run equates to your calculation unless it was always pulling 2,7 kW. Is this some 30 year old setup that doesn't have an inverter-driven compressor? Also, wow your electricity is really cheap.