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Eclipseocalypse - Electrics Brace for Solar Darkness

When the sun goes dark, California will lose the equivalent of five nuclear power plants of power.

California is bracing for a significant loss of electric power as its fast-growing fleet of solar electric panels plunge into darkness during a major solar eclipse on August 21.

While the eclipse will be partial in the state, energy planners are getting ready to tap 6,000 megawatts of electricity from other sources between 9 a.m. and noon PDT during the eclipse, according to the California ISO which oversees the electricity markets in America’s most populous state.

The new vulnerability of the massive electric grid to a celestial marvel like an eclipse reflects a massive transformation of how energy is being created and used in America – something most consumers do not ordinarily think about.

In less than two decades, America’s solar power generation has soared heavenward, from a mere 5 megawatts in 2000 to 42,619 megawatts last year.

The 6,000 megawatts California has to cover during the sun’s blackout is a massive amount of energy, the equivalent of the output of a handful of large nuclear power plants.  

Fortunately, California this summer is blessed with 5,000 – 6,000 megawatts of hydroelectric resources as a result of ample snow and rains this past winter and spring, according to Deane Lyon, California ISO shift manager, real-time operations.

“We are planning to use a variety of approaches to this,” Lyon told the Energy Times.

California ISO

At the height of the August eclipse, large utility scale solar farms will lose as much as 76 percent of power in the north while in the south the loss will get to 58 percent.

Above all, the electric market through its price signals will bring enough electric power to the market to serve all, he said. He does not anticipate any repetition of the massive price spikes that occurred in 2000-2001, when Enron manipulated energy shortages and the market to drive electric prices up 20-fold.

“We won’t see anything like the energy withholding crisis,” Lyon said.

California ISO

Deane Lyon

California state officials have aggressively promoted solar power installations at residences as well as at large utility-scale solar farms as the state aims to get half of its electricity from renewables by 2030. Solar power is playing a huge role in that effort. On one recent day, March 11, California ISO reported 40 percent of net grid power from 11 a.m. to 2 p.m. came from utility-scale solar.

Electric grid officials, utilities and energy companies nationally will be watching the eclipse closely to learn its impact on solar generation – which has lately been ramping up.

“As the number of variable energy resources on the power system increases, there is a greater reliability risk created by solar eclipses,” the North American Electric Reliability Corp. stated in a recent report. “As a result, there is an emerging concern of how to maintain a reliable and operable system during off - normal astronomical events (i.e. solar eclipses and geomagnetic storms).”

The California ISO is readying for a “ho-hum” eclipse morning, Lyon said, as markets work their magic and hydroelectric and gas-fired generation come online as demand surges at an impressive 90 – 100 megawatts a minute pace during the first 80 minutes of the eclipse.

If human intervention is needed – it will be provided. “We will have people in the control room who may manually dispatch generation we haven’t planned on,” Lyon said.



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