please evaluate my electrical situation

Ok so my average monthly usage has been between 25-29 KWH over the last year. It hit 29 last month. I have been using more electricity on purpose in preperation. I will have in my possession 2 x 400w HPS lights, 1 x 400w MH light, and 1 x 250w HPS light.

The grow room is running on a 15 or 20 amp fuse. Lets say 15 to be safe...

I wouldnt need to use the room for anything but growing so I wont need to have other personal electronics running from any of the outlets.

So I think I have given enough data for some expert out there to make a good recomendation.

If I needed to I would be willing to just turn off my water heater. I have a manual switch to turn it off. I was also worried about the pattern of 12/12. Would it be smart to compensate when the growlights are off by turning something else on... Like maybe have an A/C unit go on... Then power usage would stay somewhat the same... maybe?

Other specs incase u need to know:

growroom is aprox 10'x10'
I will have good ventilation and possibly an AC (that would depend if I can spare the electricity for one)
Outside temps range from 65F-85F