Energy Storage in Flywheels

Here’s a clean energy investment opportunity that I don’t particularly recommend, for two main reasons:

Flywheels have been around for hundreds of years, and, actually represented a viable potential solution to our energy storage needs, until the cost of batteries came down and their energy/power density improved over the past decades.

I tend to be unimpressed with presentations that are largely about the problem to be solved, in this case, global warming, and only tangentially about the solution.