Aircon is a power guzzling luxury (or maybe not so much of a luxury).
I would suggest that, at current prices, solar technology would give you a payback time which would be well worth the capital outlay.
Mind you, it would be more economical to run your AC at a sensible temperature in the region of 27ºC in the bedroom and 30ºC in the lounge and also change to inverter technology if you don't already have it.