Green Energy

According to the video, concentrated solar's costs have come down since those plants near Las Vegas were built, but it's still about 2x more than photovoltaic.

According to that wikipedia article, the Las Vegas plants require substantial amounts of natural gas heat to keep the salt temps up so it'll function into the next day, which the video didn't mention, so now I'm wondering if that requirement has been eliminated from other designs?

I think ultimately you're right in that batteries will serve the need better, especially once cheap sodium batteries become mass-produced for those purposes.