Solar prices are coming down quite fast, I don't think a factor of two is going to be a killer here if the storage is cheap and long-lasting enough. Some people are already considering over-provisioning solar panels relative to available transformers/grid connections so that they can maintain output on cloudier days. "What do we do with all the extra power when the belly of the Duck Curve [1] hits the ground" is a problem lots of people are thinking about.

[1]https://en.wikipedia.org/wiki/Duck_curve

The cost-prohibitive portion of this, which is greatly glossed over in the article and which I showed in my other reply - is that the steam generator required to recover this heat as electricity, is a massive part of the capex - more than half of the entire system end-to-end, including the solar and dirt storage. That makes the economy of it far less viable even with nearly free solar, which we're still quite far from.

Yeah, but then people should start to actual incorporate the full cost of these kind of things in the total cost of solar power when comparing it to other sources.

I think generating hydrogen for fuel cells seems prima facie a reasonable approach?