I had put a 2.5kw photovoltaic system in about 10 years ago. That had lowered my yearly cost of electricity from $2200 a year to under $300 a year, along with replacing incandescent bulbs with CFL's. It was time to replace my roof, so I decided to upgrade my panels at the same time to a 6kw system. You can see from one of the photos the difference it made going from a 2.5kw system to a 6kw system.
Nice. Curius why you did not go with micro inverters?
I have no trees that will shade any of the panels, so I felt I didn't need to pay the extra expense of the micro inverters. My old system had a central inverter also and I never had any problems with it.
Am just starting to put together info on Solar & Wind Power. Looking into building my own, as well as purchasing, where to begin? Am I right that both of you purchased your systems?
You should start by looking at your electric bill and determining what size system you need to install. Your electric bill will show you how many kilowatts of power you are using. Use a years worth of bills to estimate your usage. In my case, I oversized the system a little bit so that I could use the air conditioning in the summer months. Shop around for you equipment to get the best price.