SQLGeek: I have been quoted $17,000 for a 15 panel 4kW system using micro-inverters. Micro-inverters were a good choice as the house has 3-phase power and allows the PVs to be split over each phase. The 3-phase inverters are way too expensive, as was getting 3 x single-phase inverters.
This is a new build in Chch, with the panels going on a flat Butynol roof so the installer has allowed extra for the fittings.
A great thread, thanks to everyone for sharing.
Wow 4kW is a generous amount of generation. You have 3 phase power installed so the micro inverters make sense. Have you measured each usage phase and made a decision about which phase will get what solar generation yet? I'm interested in the grid tied aspect, you get a single meter that measures the import and export on all three phases presumably.
What is your daytime base load that you want/need a 4kW array? I understand that in CHCH you have access to very cheap night rate power which I do not have here in AKL. Make sure you have calculated what 4kW exported to the grid is worth to you compared with using cheap night rate power to heat water etc. Here in AKL I can export 5kWh per day and get paid $0.25/kWh then draw the same 5kWh back after dark and get charged $0.22/kWh so net gain, the grid acts like a battery. After 5kWh per day though Meridian pay me just $0.10/kWh. If you export the same 5kWh and get the same $0.25/kWh that's good but any surplus after that is just $0.10/kWh which is about the same as what you can buy Night rate power for to heat a large water cylinder. You need to make sure you size your PV to provide your daytime base load plus export the sweet spot 5kWh per day. (averaged over winter and summer) Investing any more in PV may reduce your ROI.