AC machine, electricity consumption?

The power consumption will relate to the difference between ambient (outdoor) temperature and AC set temperature, rather than the absolute set temperature.

The bigger the difference, the more heat will leak in from outside and the more work the AC has to do, to keep at the set temperature. More work means more power use.

Better thermal insulation to reduce heat leaking in to the air conditioned space and so will reduce running costs.

[An air conditioner is a "heat pump" system - it's not that far a stretch to compare it to a water pump keeping a hole/cellar drained, that has water seeping in. The more heat or water that "seeps in", the more time the pump runs to get rid of it and the more it costs. Reduce leaks saves money and equipment wear in either case].

The lower you set the temperature, the longer it will have to run which consumes more electricity.