While there are lot of variables that come into play for recouping, but let's keep an average for a year+. It will vary a lot. For instance I have LG inverter, my daily consumption is ~ 1.5 units. Rate is Ru 7/unit, so it comes to Ru 315/month. I am sure I will recover it in a year.
I mostly use it at night from 9pm to 5am or 9pm to 7am. ie. average 8-10 hours.
I use it at 28C since it runs all night, the temps fall to 26C by morning.