It is an eye opening experience to have a house on solar. I bought a bush property several years back, wonderfully happy with myself and the fact that it was operating as a family home on a 12 volt battery's worth of solar electricity - that is about the same as your car battery!
Well, that would have to have been the biggest learning expense I have had yet to date. To start with, a 12 volt battery barely keeps a 60 watt light bulb going overnight. So all the lights were so low I had difficulty seeing anything at night. None of ones normal appliances, like a toaster, could run off it as they require too much energy to start up, same for a vacuum cleaner or anything with a motor...
Which meant one had to turn on... the back up generator! Which, in this case, was a huge old submarine engine from the 30's that guzzled diesel fuel like it was going our of style. Looked cool though, lots of ooohs and ah's from visiting guys!
In the end I found I was spending $450 worth of Diesel fuel a MONTH that had to be ordered ahead of time and delivered in great big drums. It made my 'huge' electricity bill of $350 a quarter in the city for the whole family look really cheap!
Especially in winter, if you do not have gas heating and have to use radiant electricity. Anyway, I am now very efficient, all my equipment has been altered and turning lights off has a whole new meaning.
I did eventually get a government grant to up grade my 12 volt to 48 volts and improve the solar panels but even with a $16,000 rebate there was an out of pocket of about $26,000 as the grant only paid for solar panels not the batteries - which are really expensive and like normal batteries run out no matter how well you care for them. And then, it did not cover what is called 'distribution' which means the wires and light fittings etc that had to all be changed to accommodate the larger quantity of power now surging through them. I had to do it as, guess what, my 12 volt battery eventually gave up on me and then... no power, no matter how many solar panels you have on the roof!
My point to all this seeming whinging, is actually to share the hidden costs of this new and wonderful technology that will be great in the future. So dont be lulled into a sense of fuzzy ease by solar, it is, like wind energy, full of costs the average electricity user has no idea about but which, I am pleased to say I am now very aware of and thrilled to have a totally sustainable power supply - even if I am aware I will have to pay more upgrading for it down the road again.
I am also pleased to say I rarely have to turn on the generator, which also had to be upgraded to reduce the fuel consumption and I can almost get through the winter months totally on solar now.
I am now very appreciate of my subsidized city energy and I continue to rail at my family to turn off the lights... but I am still working on that one.