Those seem slanted more towards the industrial side than residential, the smallest apparently being about double the size I will need. (Further investigation suggests I should be looking at a system around 18-24K BTU.)

As far as staying off the electric bill... all I need to do is add solar panels (PVs) to reduce my billable kWh to below a 12-month average of 250 kWh per month, and my electricity costs will drop from a current projected $133 per month (12-month average) to $7 (not a misprint: seven dollars!) per month. Adding A/C changes the picture to somewhat less dramatic figures of $159 and $12, but still quite acceptable. [This assumes 1850 watts 8 hours per day for 2 months of the year for the A/C] The reason for the extreme reductions is twofold: the solar panels are kicking in 222 kWh per month (62% of my total consumption) and more importantly they are getting me out of the punitive DAC (Domestica Alta Consumo) rate structure. I will pay 6 cents per kWh for any electricity usage beyond the 222 kWh from the PVs, whereas without the PV's I would pay more than 36 cents for every single kWh used.

The downside to all this is that I face an up-front cost of $9000+ USD for the solar installation. My electric bill savings will amortize that in 5.2 years, and after that it's all gravy.

The PVs are to augment the existing electric service, not replace it. There are no batteries for storage, anything like that. If the power fails, I am in the dark like my neighbors. [Hmmm... if the power failed in the daytime, could I throw a switch to separate myself from the grid and use the 1400 watts from the PVs to keep important things like computers and refrigerators running?] The most important purpose is to get me away from the DAC rate.

tanstaafl.