This month i got bill of 5500rs which include 1.5 ton orient 12 hours daily usage and two 13 watts led one ceiling fan and one fridge.
So if you used it for five hour daily you would get 2000 to 2500rs/ month depends on the room size and its temperature. My room usual temp in summer is 31 and i am using my ac at 28c.
I would advice you to go for kenwood as many people says its better then orient. But i am satisfied with its performance.
Sent from my GT-I9500