April 8 Solar Eclipse Will Have Hordes of Americans Heading stretching towards the sky in your eclipse glasses. But it means more than an opportunity to worry about possible damage to your vision.

With an energy ecosystem increasingly fueled by the power of sunlight, dark skies at midday are a big problem. “The impacts on solar generation are quite significant,” Barry Mather, chief engineer at the National Renewable Energy Laboratory, told CNET.

Fortunately, because solar eclipses are extraordinarily predictable, grid operators have had plenty of time to prepare for the impacts. Because of this, most Americans are unlikely to notice any changes to the electrical system.

Here's what four-minute eclipse means for our electrical grid.

Does solar eclipse affect solar panels?

A solar eclipse, which causes a temporary loss of sunlight as the Moon blocks its rays, is very important to the growing supply of solar energy deployed in the US.

“The grid is going to have to figure out, if that energy source goes away even for a few minutes, how to match supply and demand during that window,” said Benjamin Lee, a professor of electrical and systems engineering at the University of Pennsylvania.

It may seem like just a blip — the total loss of sunlight will last just 4 minutes anywhere — but that ignores the eclipse's broader impacts.

Considering solar panels?

Our email course will guide you on how to go solar

Areas within the “zone of totality” will experience total darkness, but areas near and far from that zone will still experience a partial loss of sunlight. Additionally, although totality lasts only 4 minutes, the transition into and out of the eclipse can last several hours in some places. This means a much longer period of reduced solar generation.

“This will really impact the entire United States to varying degrees,” Mather said.

The effects could be especially acute in Texas, which has increased its reliance on solar energy in recent years and is directly in the path of totality, according to Jin Tan, NREL's principal engineer.

Will the solar eclipse affect the power grid?

The nationwide loss of sunlight during the eclipse will reduce solar generation. But this isn't just a problem for individual homeowners using rooftop solar — it's also a big blow to the power grid.

This is because utilities have invested in many large-scale solar projects, which they now rely on to keep the grid running. Each utility company is preparing for the eclipse in a unique way, Tan said, but generally they will need to ramp up other energy sources (such as oil, gas and hydroelectric plants) to cover the temporary loss of solar power.

This can be challenging due to the speed of the eclipse, Tan said. The daily transition to nighttime, which obviously reduces solar generation, is quite slow. But the transition rate during the eclipse can be nearly twice as fast, meaning utilities need to ramp up other power sources very quickly.

The good news is that this is all predictable and dealerships have been here before, most recently in 2017. NREL report notes that “the 2017 total solar eclipse came and went without causing any problems to the operation of the North American electrical power system.” There is considerably more utility-scale solar now than there was in 2017, but if everything goes according to plan, electric consumers shouldn't notice any problems.

And here's another silver lining: “This is like practice for events that… will be less predictable and happen in the future,” Mather said, like storms or smoke from wildfires that knock out solar generation without warning.

How to watch the solar eclipse

If you want to go out and contemplate this celestial spectacle, here are some tips:



Source