data available on the internet specifically for Canberra gives...

data available on the internet specifically for Canberra gives an average daily output for a 1Kw panel of 3.76KwHrs/day on a year round basis.
Other data also suggests that the time to recover the manufacture through to installation footprint would be about 10 years average. 15 months would be the bare panel at the factory door. As with many things, transport, handling, installation etc. are hugely variable and can make the original cost of the item insignificant, especially items that have to be imported.