A while back I raised the problem of intermittency — the fact that solar and wind power depend on the sun shining and the wind blowing, neither of which happens continuously — and asked if anybody knew about ways of storing energy generated during peak sun/wind and releasing it into the grid during lulls.
Ask, and ye shall receive: There’s a piece in Spectrum called "Taking Wind Mainstream" that directly addresses the issue. It contains all sorts of stuff I didn’t know and has me feeling downright optimistic.
Yet one often hears questions related to wind power’s intermittent nature; unavoidably, electricity is generated only when the wind blows. Can the power grid handle massive amounts of variable production? Can wind energy be delivered where it’s needed when it’s needed? Can wind energy harnessed at times of low demand be stored for high-demand periods? Can new storage technologies be devised so that wind energy would become, in effect, dispatchable? The answer to all of these questions is yes, and in some cases the answers are already in practice.
Wind-energy and power-transmission technologies are already adapting to accommodate the impressive growth of wind power. Large semiconductor devices referred to collectively as power electronics are, for example, enabling wind farms to provide rapid response to fluctuations in grid frequency and voltage. This is one of many reasons why grid studies consistently estimate that the cost of integrating wind power will be low. However, integration costs will rise when one considers small power grids or high proportions of wind power in a grid. In such cases, power electronics devices can be combined with energy storage technologies that operate over a range of time scales to manage the shifts in wind power production. In fact, a growing number of innovative energy storage options are providing grid operators ways to dispatch wind power in the same way they do with thermal generating plants. Continental supergrids eventually will help, too, by distributing wind-generated power across whole regions, balancing regions where the wind happens to be blowing with those that may be becalmed, while simultaneously spreading the burden of providing backup power.
The article gets quite technical at points, but it’s a real education. Be sure to bookmark this one to send to the next person who repeats the intermittency argument as though it settles the question of whether relying on wind is "realistic."