Re: “During the day the panels charge batteries that are used during the night time.”
Electrical storage devices are very expensive, for individual homes and for large commercial projects.
Can you give me a link for any solar installation where a solar + battery system is operating at a practical and unsubsidized cost?
It's still very expensive and low efficiency.
Deep-cycle batteries are expensive as well - but the way to make it work is to reduce consumption.
"Practical" is relative. I see Solar as merely a way to reduce dependence on the grid AND be ready for grid down situations - 24/7 power for the fridge, freezer, and few electrical outlets.