Earlier quoted context omitted.
Thanks for your summary. The kickstarter project was targeting 15kWh which should be more than enough for a low draw residential setting. For a one-off prototype, they asked for US$50,000 funding. Let's guestimate that with mass-manufacturing the same product could be built for US$30k, and that's going to provide a probable rated lifespan of around 20 years with zero maintenance. Contrast batteries, which might cost…
> This derives from the ability of the flywheel to perform the functions of dc-to-ac inversion and optimal impedance matching between the PV arrays and the load in addition to providing energy storage. We don't need this anymore. This stuff is easy with modern power electronics, so if this is what makes it competitive, then it's not. I also suspect the reliability is not there yet for 20 year operation. And it's not…
My understanding is that AC/DC conversion is lossy and rule of thumb figures online quote 10-15%.
> I also suspect the reliability is not there yet for 20 year operation.
A lot of products already on the market have 20 years lifespans quoted, eg. Socomec FLYWHEEL, Vycon.
> I've read about a large number of companies that have tried, and yet they all seem to vanish.
Sources? I am genuinely curious.