> My understanding is that AC/DC conversion is lossy
We don't need to do this all that often, and the flywheel is lossy too. And you can get 96% efficient power supplies http://en.wikipedia.org/wiki/80_PLUS
> A lot of products already on the market have 20 years lifespans quoted, eg. Socomec FLYWHEEL, Vycon.
This could be new - I haven't been following this recently.
> Sources?
When people first started focusing on automobile energy efficiency flywheels were the thing. They eventually gave up and switched to hybrids, and/or batteries.
The stores would have a pattern: Some young new company proudly showing off its new technology to the fawning journalist - and then that would be the last you would ever hear of them. (Someone once told me to put their names in a google news alert then forget about it - most of the alerts would never trigger a second time.)
> We don't need to do [AC/DC conversion] all that often, and the flywheel is lossy too. And you can get 96% efficient...
Sure, even looking at that page 10-15% does seem a regular rule of thumb though. Many devices in the home (computers, displays, etc.) require DC. Photovoltaics produce DC, but not necessarily at a level suitable for variable, direct load by devices. So in a sustainable source powered situation, you have to pay for this loss somewhere: either in storage or inversion or both. It would seem that the 1979 author was refering to the flywheel's potential toremove the 'double tax' for storage and inversion. The listed 'motor generator' benefits (load and spike isolation, etc.) would also seem to apply.
> this one is high profile and recent
Beacon are often referenced. It seems they were revived and the major facility they built is still in operation. They cited a combination of DOE policy and 'the current political environment' as their cause of temporary bankruptcy.
We don't need to do this all that often, and the flywheel is lossy too. And you can get 96% efficient power supplies http://en.wikipedia.org/wiki/80_PLUS
Plus you can use http://en.wikipedia.org/wiki/Rotary_converter and http://en.wikipedia.org/wiki/Motor-generator which are basically the same thing, minus the energy storage part.
> A lot of products already on the market have 20 years lifespans quoted, eg. Socomec FLYWHEEL, Vycon.
This could be new - I haven't been following this recently.
> Sources?
When people first started focusing on automobile energy efficiency flywheels were the thing. They eventually gave up and switched to hybrids, and/or batteries.
Note the date: http://www.nytimes.com/1994/06/22/business/flywheels-to-powe...
I don't really have any links from stories from years ago, but this one is high profile and recent:
http://www.washingtontimes.com/news/2012/apr/9/feds-call-ban...
The stores would have a pattern: Some young new company proudly showing off its new technology to the fawning journalist - and then that would be the last you would ever hear of them. (Someone once told me to put their names in a google news alert then forget about it - most of the alerts would never trigger a second time.)