Energize Weekly, January 3, 2018
Utility-scale renewable energy generation surpassed nuclear generation for the first time in three decades in March and April of 2017, according to the federal Energy Information Administration (EIA).
While the phenomenon appears to be temporary, in 2017, it is marked by a series of trends that may realign generation sources over time.
Nuclear generation has remained flat over the last three decades even as there has been a surge in utility-scale wind and solar generation—accounting for more than 60 percent of all utility-scale electricity generating capacity that came online in 2016.
About 27 gigawatts (GW) of generating capacity came online in 2016, the largest increase since 2011, including 8.7 GW of wind and 7.7 GW of solar.
From March 2016 to March 2017, wind generation increased by 16 percent, and solar generation increased by 65 percent. In April, solar generation continued to rise, while wind generation fell slightly. EIA projects year-over-year increases of 8 percent in wind and 40 percent in solar in 2017.
Five nuclear plants with about 5 GW of capacity were retired between 2013 and 2016, although in 2016, the first new nuclear plant since 1996, the Tennessee Valley Administration’s Watts Bar Unit 2, went into service with about 1 GW of capacity.
“Retirements of a number of nuclear plants have resulted in a slightly lower level of overall nuclear generation capacity, and in turn, a lower level of generation,” EIA said.
The surge in wind and solar and the stalled growth in nuclear are, however, only part of the story.
“This outcome reflects both seasonal and trend growth in renewable generation, as well as maintenance and refueling schedules for nuclear plants, which tend to undergo maintenance during spring and fall months, when overall electricity demand is lower than in summer or winter,” the EIA said.
Conventional hydroelectric generation is the largest source of renewable power in most months, and pushes to record levels by heavy precipitation in the West. EIA is projecting a 14 percent increase in hydro generation for the year.
While hydro was getting a surge from the spring melting snowpack in California, and wind and solar were on their way to posting record years, nuclear generation was at its lowest monthly levels since 2014.
While wind and solar generation follow seasonal patterns that lead them to fluctuate, monthly fluctuations in nuclear generation largely reflect maintenance schedules. In March, 14 GW of nuclear capacity, about 14 percent of total nuclear capacity, was offline for servicing, according to the U.S. Nuclear Regulatory Commission and EIA data. In April, 21 GW were offline, equal to 21 percent of all capacity.
The EIA Short-Term Energy Outlook projects that monthly nuclear generation will have overtaken renewable generation in the summer of 2017 and that nuclear will still generate more electricity overall than renewables in 2017.
For 2017, the EIA Outlook estimates coal-fired generation at 3.35 billion kilowatt-hours (kWh) a day; natural gas at 3.48 billion kWh a day; nuclear at 2.2 billion kWh daily; conventional hydro at 0.819 billion kWh a day; all other renewables at 1 billion kWh a day.