During the most recent total solar eclipse visible in the United States, on August 21, 2017, the sky darkened as the moon passed in front of the sun. It blocked out all sunlight—except for a visible golden ring around the moon's shape, called the corona. Not surprisingly, solar power generation across North America dropped for several hours from the first moment the moon began to cover the sun until the sun's disk became clear again.
On April 8, 2024, another total solar eclipse will be observed across the United States, causing an even greater loss of solar power generation. Although this is the second total solar eclipse visible in the United States in less than seven years, these events are a rare occurrence. Nevertheless, they present a unique challenge to power grid operators.
I am an aerospace scientist Interested in teaching physics and astronomy. Although I have seen many partial solar eclipses, I have yet to see a total solar eclipse. My October 2023 road trip to Bryce Canyon National Park in Utah to see the „Ring of Fire” annual solar eclipse was unforgettable, and I'll definitely find myself handing out eclipse glasses again on April 8th.
When the moon's shadow blocks the sun
During a solar eclipse, the Moon partially or completely blocks the view of the Sun. The Moon is almost 400 times smaller than the Sun and approx 400 times closerThe The shadow of the moonAs seen from Earth, the width decreases 70 to 100 miles (112 to 161 kilometers).
Within this area, called the path of totality, viewers see a total solar eclipse. Observers near but outside this path see a partial solar eclipse, where the Moon covers part of the Sun's disk.
On April 8, 2024, during a total solar eclipse, The The path of perfection The continental United States extends from Texas in the south to Maine in the northeast. Elsewhere in the U.S., Miami will see a partial eclipse in which a maximum of 46% of the Sun's disk is obscured. In Seattle, far from the path of totality, the Moon will only be at maximum 20% of the Sun. In South Texas, where the path of totality first crosses the United States, the eclipse will last less than three hours, totaling just 4 minutes and 27 seconds.
Increasing reliance on solar energy
The global trend towards renewable energy has seen a significant increase in solar or photovoltaic power generation over the past decade. Solar power generation capacity is set The whole world is twin Between 2022 and 2028, the US now has the capacity to generate Three times more solar energy than the timing of the 2017 total solar eclipse.
Cloud cover is the most obvious barrier to solar power generation. On a cloudy day, the energy produced by the solar panels decreases 10% to 25% Its release on a sunny day.
The North American transmission grid is divided Six main areas And Over 150 Local and regional subcommittees. Power system operators in each local grid continuously balance the amount of electricity generation with the „load” or electricity demand of consumers.
System operators can tap power from this Various power generation mechanisms Solar, wind, hydropower, natural gas and coal etc. Local grids can import and export electricity to their grid as needed.
System operators have accurate models of the amount of solar power across the United States on a daily basis, and these models account for areas of the continental United States with cloudy skies. By combining solar power generation with battery storage, electricity from solar power can be accessed even when the sun is not shining – on cloudy days or at night.
To plan for an eclipse, power system operators need to figure out how much energy production will drop and how much power people will draw from reserves. On the day of the 2017 total solar eclipse, for example, solar power generation in the United States 25% decrease Below average.
Grid operators may be required at reserve rates as solar power production declines rapidly during the peak of the eclipse. Power transmission lines. To keep things running smoothly, grid operators rely on local reserves to reduce power transmission between phases During the event. This should reduce the load on transmission lines in local grids and prevent temporary blackouts.
AP Photo/Matt Rourke
Renewable energy during the eclipse
Renewable energy isn't the only type of production that goes down during a solar eclipse. Due to the lack of sunlight, the temperature drops along the path of the eclipse 10 degrees Fahrenheit (5.5 degrees Celsius). Lead to lower temperatures Slow wind speed and less wind power generation.
During the August 2017 eclipse, the loss of renewable power generation increased by approx. 6 GW. This equates to energy use 600 million LED lights Or 4.5 million houses.
Grid operators compensated by planning ahead and increasing power generation Natural gas and coal fired plantsIt is not dependent on sunlight.
During the eclipse, this increase in non-renewable energy use was approx 10 million pounds Additional carbon dioxide emissions. That's about as much carbon dioxide as 1,000 cars emit per year.
On April 8th, eyes across the United States will turn upward to view the eclipsed sun.
Thanks to the vigilance of electric grid operators, the lights should stay on, and visitors won't have to worry about anything but the stunning view in the sky.