Basically anti-wind and solar advocates, deride it's 30% capacity factor.  While nukes burn 90% of the time, 90% capacity factor?  It's confusing and misleading. 

http://gristmill.grist.org/story/2008/2/5/163728/0138#39

A different way to look at the capacity factor of combined sources that meet load through a smart grid is necessary.  Wind, wave, solar, peak at different times, biogas can be stored and hydro power too.  

Large demand like heating/cooling can be stored in buildings and turned on and off to adjust demand to supply.  Some kind of an inverse capacity factor is needed for that part of the interactive system.  Storage factor related to total capacity factor.

Plugin hybrids can be charged to adjust supply and demand too.  

Total kwh demand over different time periods versus total supply over that same time period, measured at different intervals, compared to the amount of available  storage through smart grid demand managment.

I would think that a distributed network of internet devices, that switch power on and off, governed by simple fractals guiding the power management from each home, solar panel, plugin car, and wind farm would provide astable power.  

The vital things we need would stay on no matter what.  Less vital home and business power uses would be adjusted to supply and done ahead of time, the energy stored as heat or cold or water pressure in your home water system.

The old central power plant that is overbuilt to meet the biggest possible peak load is obsolete, and so is the mind set of it's proponents.