I guess Mike, the idea is to have about double the solar cell capacity, to what the TX draws - so during daylight, you are not only powering the TX for free, but are also selling power to the Grid.
During darkness, you of course, have to pay for the power you buy back .

I think the huge cost of batteries, would never be recouped, & in my experience - batteries usually have a limited life span anyway.

In a very few years, there will be a lot of second-hand cheap electric cars on sale, with very limited range due to failed batteries - mark my words!