Derek,
Your figures are incorrect, as it depend on your number of panels, I have 12 for a max of 3KW, but you rarely get to peak performance, due to variables like temp, cloud etc. The hotter it is, the less you generate, as Canabus mentions in his post. Canabus mentioned a total of 45,000kWh, but not over any particular period, if I got it right. To not have a power bill, you have to be on the early FIT schemes where the brilliant government was buying the power for either 60 cents or 44 cents and then selling it back at up to 32 cents. Clever people!
The best way to use the system is to use the power as it's generated, by running your machinery while the sun is shining.
Once it's exported they now give me 15 cents, but when I need to buy it back it costs me around 32 cents, and until late last year I was only getting 6 cents feed in.
I'll do another post late today after I get my days performance, as I'm not smart enough to know how to check past performance on the inverter.
And you are right about the misleading advertising, although it does pay itself off over time, and if you use it to best advantage.
Ian.