Its a good thing that there are an abundance of other renewable and clean, energy generating technologies that can supply all of our energy needs, that include, but are not exclusively, wind and solar energy.
So while wind and solar energy may not be able to supply 100% of energy needs, (as opposed to wants), combined with other renewable sources, and a change in the way people live and think, 100% is an achievable goal. It will take a vast change in political will, and in the way we view our consumption and pollution, but I am optimistic.
Regardless of whether people change or not, nature will force the change eventually, and it is the people who made the choice to adapt, that will survive. This is already happening.