Well I would say that I am one of the early pioneers that bought their solar system 2 years ago. Back then the cost of my system was 18k and it has been well worth it due to the REBS and FIT in WA. That being said, I have not paid a single bill since april 2011. I have received credit every single billing cycle. I do have a 5KW SMA inverter with 32 Suntech 190w panels. It was worth it at the time, because of the government rebate. during the day we try not to use much power. We do all our power usage at night For those looking at getting solar now, since there is no REBS or the Fit, you will need to check and see how much power your consume during daylight hours. If you use more power at night, then it is not worth getting a big system. If you are able to move most of your power usage to daylight hours, for example set the dish washer, the washing machine, the pool pump and things of the sort to run during the day, then you would need to look at a system to cover that usage. If you go with a big system now, you ROI would be more than 7 to 10 years and it is not worth it. If you want to see what sort of figures you might get, this website(www.pvoutput.org) can be helpful to search of similar systems in your area and how much they are producing. Just do a search by your post code. This is my system http://www.pvoutput.org/list.jsp?id=1660&sid=1268 Systems similar to mine, will cost about 8-10k depending on where you shop. There is no warm fuzzy feeling about saving the environment if you go solar. There is a warm fuzzy feeling when you have no bills to pay and you get credit to pay off your loan.