Rare Solar Eclipse Serves As Renewable Infrastructure Stress Test

Unless you were alive in 1918, the total solar eclipse that passed over North America this past August was a first-of-its-kind event. And while millions of Americans turned their gaze skyward in excitement for the eclipse, the energy industry was busy watching to see how our nation’s solar infrastructure would be impacted.

According to Environment America, the nation generates 43 times as much solar energy now as it did a decade ago. Among the many reasons for the increased rate of adoption is the security that comes through diversifying energy supplies derived from one of the most stable sources possible—the light of the sun.

But what happens on the rare occasion when the lights go out?

California Sees Dip in Generation, Suffers No Outages

As one of the most pioneering states for adoption of renewable energy, California was in the spotlight in advance of this year’s solar eclipse. Officials estimated ahead of time that they expected the state to lose roughly 4,300 megawatts (MWs) of generation by the time the eclipse passed through the state—enough electricity to power between 3.2 and 4.3 million homes. Once the eclipse passed through, the state estimated actual losses at just 3,400 MWs.

Despite the dip in production, energy officials throughout the state were quick to supplement solar output with more support from both hydro-electric and thermal sources to make up the difference. The state also leveraged the Energy Imbalance Market. This allowed authorities to purchase power from other western states within the hour it was needed.

PJM reports slight dips in generation in the Midwest

PJM also reported slight dips in generation throughout the course of the eclipse in the Chicago area. It recorded a drop of 520 MWs of wholesale solar generation Roughly 1,700 MW from behind-the-meter solar generation attributed primarily to rooftop solar installations that offset loads.

While it is still studying the final impact of the event, PJM also reported a decrease in demand for electricity of about 5,000 MW throughout the eclipse. This could contribute to the minimal stress the eclipse placed on the grid in the Midwest region.

Mid-Atlantic Sees Major Decline, But Meets Demand

As the eclipse made its last stop in the Mid-Atlantic states, energy suppliers were bracing for a challenging day. At the height of the eclipse, 1,700 out of 2,500 MWs available in peak conditions were blacked out. Despite the higher impact on their relatively smaller grid infrastructure, none of the Mid-Atlantic states reported any outages.

Overall, energy industry professionals took the necessary precautions to ensure that customer demand was met without interruption. While the results were positive, it must be noted that this eclipse came along with lower temperatures. This offset demand at the same time generation dipped, giving the grid a little added reprieve.

While this was in many ways the first true test of our nation’s solar grid infrastructure, there will be another litmus test in seven years, when the next solar eclipse makes a path across the North American continent.

In the meantime, discuss the importance of diverse energy supplies and increased storage capacity. Learn more about how to develop a comprehensive energy strategy to make sure your demand is always met.