- The solar eclipse on April 8th will affect solar power generation.
- In the United States, the path to totalization stretches from Texas to Maine, but other states will also be affected.
- Due to increased solar power generation, the impact will be about three times that of the 2017 solar eclipse.
On April 8, millions of people will wear eclipse glasses to watch the moon pass in front of the sun. This event will impact solar power, but everyone's lights should still be on when you return indoors.
In the United States, a total path where the moon will completely block the sun will stretch from Texas to Maine. But utilities in other states that use large amounts of solar energy also need to have power reserves, Barry Mather, an engineer at the National Renewable Energy Laboratory, told Business Insider.
“This eclipse will actually affect solar power production across the entire North American continent,” he said. When the moon blocks the sun, it reduces the amount of sunlight your solar panels receive.
However, being able to predict exactly when and where a solar eclipse will occur allows power companies to plan to avoid power outages.
“I fully expect all of us to be ready for this,” Mather said.
More solar power is being generated in the U.S. than in 2017
There are quite a few reasons why this year's solar eclipse will be different from past solar eclipses.
Total solar eclipse in America in 2017 We took a completely different and complete route this year, moving from Oregon to South Carolina in the United States. Mather said the country has started generating about three times as much solar power in the past seven years.
“The market is growing so fast that the impact will be about three times what it was in 2017,” he said.
But Mather said the battery had little energy storage during the last solar eclipse. “We don't have a ton yet, but we do have some,” he said.
To compensate for the decline in solar power, utilities will need to rely on other sources of power.
There should be no power outages
On any given day, Mather said, utilities already plan how much electricity they'll generate and where it'll come from 10 days in advance. Solar eclipse days are no exception.
“One of the things we're doing here at NREL is really working with a lot of the organizations that are most affected by the eclipse,” Mather said.
As the day approaches, the weather forecast changes and plans may change slightly. For example, if it is cloudy, solar power generation will not be affected as much.
One way utilities are preparing is by planning for more reserves, or additional generation that can come online and provide additional power when needed, Mather said.
“We actually observed this during the 2017 solar eclipse, specifically in California,” he said. The state has an abundance of solar power.
“So even if solar power starts to decline and power starts to drop, it will have very little impact on the grid in terms of frequency, voltage, all kinds of metrics that we track as power systems engineers.” he said.
Reserves typically use less environmentally friendly energy sources, such as coal or natural gas.
Solar eclipse will affect California, Alaska, and other locations outside total orbit
All eyes will be on the skies over Texas, where densely populated cities like San Antonio, Austin, and Dallas are on the path to completion. It's also a state rich in solar power and its own power grid.
“In Texas, we estimate that about 14 gigawatts of power will go down,” Mather said. According to the Energy Efficiency and Renewable Energy Agency, just 1 gigawatt is enough to power 100 million LED light bulbs.
To humans, solar eclipses appear fairly quickly, taking only a few minutes for the moon to pass by the sun. It's different with solar panels, Mather said. Low intensity sunlight is irradiated onto the panel for more than 3-5 minutes.
“The sun begins to be blocked more than an hour before a total solar eclipse occurs,” he said.
And the weakening of sunlight will affect California and other states with solar panels.
While we're far from perfection, “the San Diego generation, for example, will still be down by 50% or thereabouts,” Mather said.
“There is so much focus on the path to wholeness, and there is no doubt that it is a very wonderful thing to experience as a human being,” he said. “But from a power system perspective, it's really going to have a national impact.”
