Another article touting Elon Musk having a revolutionary idea...when it has already been in practice for years (decades) elsewhere. I have a friend who built a house in Czechia 10 (15?) years ago and contracted with the local power company to put excess power back into the grid.

I'm working with companies here in Austria (a branch of a German company) to build solar powered awnings and railings for our flat, and contract to feed excess power either to batteries or back to the grid. The company in Germany has been around for 20 years.

We're planning on buying only one battery now, as I expect the price for battery storage to drop by a factor of 5-10 in the next 10 years, as it has done the last 10 years.

All of this is not new.

https://www.wien.gv.at/wohnen/baupolizei/pdf/merkblatt-photovoltaikanlagen.pdf