Solar Power and Solar Hot Water

Since getting my 1KWh Solar PV system installed late last year I have been watching how well it performs. We have reasonably ideal conditions for the system. North - NNW facing roof, high enough pitch to match the latitude and a light colour, thus hopefully providing cooler conditions on the very hot days.
So far the system has averaged 5KWh per day until very recently.
Lately the generation has started to fall off somewhat. On good days we were getting over 6KWh/day whereas now its struggling to reach the 4.5-5 area. As the equinox has just past and the hot weather is still continuing, conditions which reduce the solar gain, so we will have to see how the system goes in the later part of the year, when the spring equinox arrives in September.
It has also been quite cloudy so on these days we struggle to reach 2-3 KWh.

I am still awaiting my federal government rebate and also still awaiting my electricity bill. So far we seem to have put a reasonable amount of electricity back into the grid, enough to halve the electricity bill. But having a very warm summer also has meant more than usual use of air conditioning (easy since we didn't have it last  year!) so at least some of the watts and $$ generated have been used to keep us cool.
I am hoping my new meter is also set up to keep the off-peak tariff that we used to have before the installation of the solar power. Time will tell as to how efficient my electricity provider is in the billing side, and whether I can  figure the bill out!