Study: Power Storage Not as Crucial as Once Thought

A new German study indicates that power storage for intermittent renewables won't be needed nearly as much as commonly thought, at least until that nation is getting nearly half its power from renewable sources. The study, done by the German VDE Association for Electrical, Electronic & Information Technologies, indicates that power storage will only become crucial -- and costly -- as Germany approaches the point where it's getting 80 percent of its power from renewable sources.

 
Storage is generally considered necessary to even out power flows when the wind dies down and the sun doesn't shine as brightly. But the VDE study, available here in German, cites Denmark as an example of a nation that's ramping up its renewable capacity just fine without storage. Denmark now obtains 40 percent of its electrical power from renewable sources with has essentially no power storage infrastructure.

Another finding of the study: Though some pundits have maintained that intermittent renewables make a steady source of baseload power all the more important, that's not borne out by Germany's experience so far. At 25 percent renewables in 2012 with little storage to speak of, Germany is finding itself with less need for baseload power such as nuclear and coal.

The more renewables, concludes the study, the less need for baseload power.

That's important because of Germany's national policy in the wake of Fukushima and other nuclear plant incidents is to phase out nukes over the next few years. Critics have charged that subtracting nukes from the country's increasingly renewables-heavy power portfolio means the central European nation will be forced to rely on coal as a source of baseload power. On the contrary, however; the report projects Germany phasing out coal entirely as its percentage of renewables climbs to the 80 percent level.

What does this mean for California? It means we're a long way off from needing to worry about storage, if it's fair to extrapolate from the German study. On a typical day in California renewables -- solar, wind, geothermal, biomass and biogas, and small hydro -- contribute about 10 percent of California's power demand. Much of that power is potential baseload power. Check out the CaISO's graph for renewables feeding into the grid Sunday, March 24:

Just under 2,000 megawatts of the renewable contribution to California's grid is rock-steady, 24/7 potential baseload power. If that grows at anywhere near the rate solar and wind will be growing in California, we may be able to skip storage for the time being, get off coal, and phase out the state's two remaining nukes -- one of which seems down for the count anyway.