Your units are wrong, kw not kwh. And your decimal place is wrong, the going rate is around $3 per watt.

And I'm not sure how you were trying to relate that to battery storage.

Solar panels have indeed become much cheaper, although it is important to distinguish between energy "provided" and energy "stored." Which why the combination is so important. It is often great to look at solar in terms of a "solar day" which is defined as the hours during which the panels deliver peak capacity. On my house, there is about 6kW of solar panels, and under optimum productions they produce for 5 hours in a day, so a total of 30kWh. What gets to the house or the grid is reduced by efficiency losses and the difference between performance under "standard test conditions"[1] and what is actually their environment. My house reliably produces just over 5kW at its peak or about 25kWh in a solar day.

In California, if you are tied to the grid as my system is, you are still at the mercy for how much the power company will credit you for power you generate vs charge you for power you consume. That has been a source of argument hear for the last 20 years. With sufficient local storage, you can completely disconnect from the grid and that removes this pricing power of the power company over your energy production. Something I hope to do within the next 5 years.

[1] This is sort of the MPG equivalent rating for solar panels, good for comparing panels to other panels but bad for guessing how much power they will produce for you.

Two months ago I got 6.8kW installed on my house for $13,000CAD. Some of that was DIY, but I just bought the whole system retail.

So just under $2 CAD/kW installed and running - inverter, licensed electrician and permits, everything. (That's under $1.50 USD/kW)

The panels are now cheaper than when I bought them too :)