@Howard_Z
My bad, a bit more info for you. Think I've gone through this here before here but roughly as follows.
In Oz 5 KW of panels on roof and connected to the grid via a smart meter, that meter measures incoming and outgoing demand, simply replaces the old meter and is a free service. Our bills used to be about AU 2,600 per year and after installation dropped the annual bill to AU 5/600. The supply and install on that system was AU 3,400 and back then the thinking government wanted more people to install solar and gave carbon credits and tax incentives that made it viable for the average punter like me, at that time 12/14 years ago decent batteries were cost prohibitive unlike now.
Around 31% of Aussie homes have solar in greater and lesser degrees.
Here different kettle of fish, no incentives and they tax the sh1t out of every component so here an 11.4 solar array, 4 x 10Kw LI02 batteries and 2 x 5Kw invertors with linking kit/load sharing supply and install was just under AU 38K.
We sized the system to produce 40 to 50Kw per day and enough storage to only drop the batteries to 50/60% capacity with overnight usage.
Prior to installation we were using around 23Kw per day with a monthly bill of P 10 to 11K per month with Luelco. We were careful with usage with general running and the master B/R A/C for 12/14 hours a day.
Now running 1 unit 24/7 and the office for 12 to 14 hours and the system is charged by 12 to 1pm and throttles back, yesterday we ran those 2 x 1HP units and a 2.5HP unit in the living area (fantastic) from 9am till 5pm and the batteries were fully charged by 2 pm and throttled back to 3KW for usage. Yesterday was 40KW input.
The max so far we see for input is 9.5 Kw per hour, rainy days 3 to 5 Kw. Rainy days less need for A/C.
The power company here wanted huge fees to grid tie, required running new cables and conduits 45/50 meters and a 4 to 6 month wait for them to install an extra meter, the buy back is 4 to 1 whereas Oz was 3 to 1. Costs to accomplish? Another P 150K,,,, 10Kw of battery is 185K. As mentioned before I asked the engineer that came here for the site inspection (Luelco) why an extra meter? We need that to measure what you put back sir,,,,,, you don't have smart meters? He looked at me stupid, explained that for 20 odd years Australia simply uses 1 meter and no need for extra cables and costs,,,,,, no sir I've never seen that.
So that's why we will be a 6/7 year ROI.
Cheers, Steve.