But as Matt Roberts, executive director of the Energy Storage Association, which represents the energy storage industry, puts it, ”The idea that intermittency is a challenge for the grid fundamentally misunderstands how the grid operates. We have a whole toolbox of ways to deal with intermittency.”
The truth is that every source of energy is variable in its own way. For example, the cold wave that struck the U.S. Northeast in early 2014 disabled three-quarters of New England’s gas-powered generation capacity because contractual limitations and exceptional demand impeded supplies.
“Hardly a month goes by,” the DOE’s Energy Information Administration reported in 2006, that delivery from Wyoming’s Powder River Basin, the nation’s largest coal reserve, “somewhere in the supply chain is not interrupted by a derailment, freezing, flooding, or other natural occurrence.” Amory Lovins, cofounder of the energy research-focused Rocky Mountain Institute, reported in a May article in Forbes that coal plants experience outages 6 to 10 percent of the time, and are unavailable for one reason or another for about 15 percent of their maximum theoretical output. That compares unfavorably with solar and wind equipment, which contains few moving parts and rarely breaks down.
The grid was built around the idiosyncrasies of fossil fuels, so long ago that they’re taken for granted. In optimum circumstances, fossil fuel and nuclear plants deliver a constant supply, which meets the system’s minimum daily electricity demand. As demand rises to a late-afternoon crescendo, when commercial and residential devices are both in use, the increase is met with idle plant capacity and smaller “peaker” plants that function only during peak hours. This arrangement works, but it wastes unused plant capacity.
By current standards, coal and nuclear plants are also clunky: They lose efficiency when they don’t run at full capacity, and they take hours to start and stop. Refueling takes them out of service — in the case of nuclear plants for weeks at a time. They are slow to adjust to the never-ending fluctuations of electricity demand, which occur not just day to day and season to season, but minute to minute.
By contrast, the implements of the modern grid — renewables, electricity storage, and smart grid technology — respond quickly to shifts in electricity demand, and show promise of greatly reducing electricity costs. For example, with the aid of Internet links, “smart” refrigerators and water heaters track changes in electricity prices and maximize electricity use when supply is high and prices are low. When Perry declared in his memo that baseload power “is necessary to a well-functioning grid,” he was dating himself, like a horse enthusiast in the era of cars.