It has long been my position on renewable energy that the only way it will become a truly dominate energy form and not just a niche player is to have large scale energy storage solutions in place. Personally, I stand behind Tesla, Gigafactories, and the Tesla Energy grid storage products (Powerpack and Powerwall). Those seem, though not off and running full speed yet, very real, and very important to the future of renewable energy. That said, it has long been the renewable advocate position that renewable energy intermittency is not a serious problem. When this comes up, and it came up again in a recent Bill Nye Saves The World episode, the renewable energy spokesperson is quick to talk about things like pumped storage, geothermal solutions, and solar thermal. And sometimes batteries don't even come up at all (they were not mentioned on the Bill Nye episode). Here's my problem. Those other solutions don't feel real. They seem like vaporware. The same vaporware the coal industry is peddling with clean coal and carbon sequestration. Which of these energy storage concepts are real? How can the average person tell? Is carbon sequestration real? Who is actually going to build any of it? And by real, I mean a) it actually works, and b) it can be built on a large scale, and c) for a reasonable cost. Right now, it looks to be like Tesla battery solutions are about the only energy storage solution that has crossed into the realm of reality. Everything else looks permanently stuck in concept, research, or demo phase, just like energy storing flywheels, fusion power, and fuel cell vehicles. Pumped storage seems viable, but how much space does it require, what is the impact on water resources, and why haven't I heard of even a single case of one being built? I think there are already a couple of solar thermal plants, but how long into the night do they provide power, how efficient is that process, and is it really scalable?