Right, these alternative energy storage systems are untested technology. Contrary to your prior claims, they're not being built at grid scale currently.
You mean, they are not being operated at grid scale, currently.
Things still being built need to finish being built before they go into service.
Just yesterday, you said some unspecified "breakthroughs" would be needed. Now you point to construction not finished. You are clutching at straws. The more honest course would be to admit you were just wrong.
The construction hasn't even begun on these projects, and it's unclear whether they will actually be built. The Utah project is still trying to secure funding, We do need a scientific breakthrough to make storage possible. Grid scale hydrogen electrolysis could be that breakthrough, but we don't know if it will live up to expectations.
Energy storage is far from a solved problem. You insist that it's been solved, but none of your proposed solutions have actually been implemented.
Well-understood energy storage methods need to be built out. Building out takes time. We already knew that. We also know we don't need any breakthroughs before we can build out. We have methods that work now.
That is not to say there won't be breakthroughs, too, that make storage even cheaper to build out. But any storage already built will continue working as well as ever. Any hoped-for breakthroughs that don't pan out will not stall build-out. The worst that can happen is costs plummeting not quite as precipitously as had been expected.
We already see utility-scale hydro storage in use, and utility-scale iron-air battery factories under construction, and utility-scale liquified-air and ammonia-synthesis plants under construction, and utility-scale investment in hydrogen synthesis and storage. Each additional storage technology that begins to come online only improves the picture.
Repeating, again and again, that things that still need to be built out have not been built out yet sheds no light.