What happens to solar power when it isn't sunny? A simple question with an amazing answer.

"How does solar energy work when there's no sun?" has been a question for pretty much about as long as solar energy has been a thing.

Of course people wouldn't want solar panels on their houses if installing them meant that, come sunset, the movie they were watching suddenly shut off, forcing them to read by candlelight like colonial settlers. Making solar power a viable option, even when the sun sets or disappears behind some clouds, was one of the first things scientists and engineers had to figure out.

Photo by Andreas Rentz/Getty Images.


When the first devices that could capture the sun's energy were invented, they weren't very efficient.

Much like touch screens or video chatting or Dorito-flavored taco shells, solar power is one of those perfect ideas that took a while to get just right. Believe it or not, the earliest solar devices were introduced in the 1800s.

In 1878, Augustin Mouchot invented a device that could freeze water using the concentrated power of the sun. It was a cool experiment but not exactly reasonable or viable options for large-scale energy production.

No one wants this on the roof of their house. Photo via Wikimedia Commons.

Mouchot won a gold medal at the Universal Exhibition in Paris for his invention, but his device was gigantic, and coal was quickly becoming the go-to for efficient energy, so it didn't catch on.

The other downside to his invention? The solar-powered water-freezer only worked on (you guessed it) sunny days. But, that was 1878. Things have changed a lot since then.

Over the last century, the efficiency and feasibility of solar power has dramatically increased, and it's getting better every day.

Just look at this fun, easy-to-read chart!

OH GOD, MY EYES! Photo via National Renewable Energy Laboratory.

I know, I know, it's a lot to take in. Just know that it's showing you that since 1975, we've gotten better and better at efficiently converting the sun's rays into energy that can power our homes, businesses, and even a few cars and planes.

So how does solar energy keep providing power when the sun goes down?

The answer is pretty simple: storage.

Photo by Uriel Sinai/Getty Images.

Today's solar panels are designed to soak up more energy from the sun than we actually need and store it for later.

The way they do it is pretty amazing. Photons (aka light particles) hit the solar panel really hard — so hard that electrons (aka what electricity is made of) get knocked loose. Then the solar panel guides those loose electrons into a battery or superconductor that can store them. If an area has a reliable electricity grid, homeowners can just hook their solar panels right up to it. For them, nothing changes from their normal source of power except (usually) a smaller electricity bill.

A lot of people don't realize that going solar doesn't have to mean going "off grid," says Dan Whitson, solar manager for Green Audit USA in Long Island, N.Y.

"The grid is pretty reliable here, so battery options aren’t necessarily cost-effective on Long Island," Whitson explained over the phone. "But that’s something we have to explain to homeowners that, you know, you’re still going to be connected to the grid even though you’ve gone solar."

If there are solar panels on your roof, it's not like your PlayStation is plugged directly into them. The solar panels run into your regular power lines and help offset some of the energy cost, or they run into a box that will store the electricity, quite literally, for a rainy day.

Solar farms are power-plant-scale versions of this concept.

A solar power plant in China. Photo by STR/AFP/Getty Images.

They can be built in the middle of a desert where the sun is incredibly powerful and cloudy days are rare. The panels can even pivot automatically to follow the sun's path across the sky.

After the panels soak up as much energy as they can, the energy is transported to nearby cities. There's a solar farm in Austin, Texas, that produces enough power for 5,000 homes and offsets over 1 billion pounds of carbon dioxide emissions.

Oh and, yes, solar panels can still collect energy on cloudy days. They're just not as efficient about it.

That's because clouds don't block all the sunlight, just some of it. If you walk outside on a cloudy day and can still see, that's because there's still sunlight, even if it's a bit more muted than usual.

The sun is unstoppable. Photo via iStock.

That's where storage and the grid come in. Energy companies rely on the grid to offset any dips in production they might experience on a cloudy day.

"All of the reputable solar production calculators out there take in 20 to 30 years of weather data based on region," Whitson said. "So they can predict how much sun you’re going to get throughout the course of a year. Most projections are taking into consideration that it’s not going to be sunny every day."

Also, as previously mentioned, efficiency is one of the key things scientists are constantly trying to improve about solar panels.

"How does solar energy work when there's no sun?" is a simple question that cuts right to the core of a pretty huge idea.

It's the type of question that scientists, engineers, researchers, and experts around the world have to ask every single day in order to get better at what they're doing.

Photo by Ian Waldie/Getty Images.

It's the type of question that brought solar energy from an obscure experiment to a feasible source of electricity that powers millions of homes around the world.

Heroes
via bfmamatalk / facebook

Where did we go wrong as a society to make women feel uncomfortable about breastfeeding in public?

No one should feel they have the right to tell a woman when, where, and how she can breastfeed. The stigma should be placed on those who have the nerve to tell a woman feeding her child to "Cover up" or to ask "Where's your modesty?"

Breasts were made to feed babies. Yes, they also have a sexual function but anyone who has the maturity of a sixth grader knows the difference between a sexual act and feeding a child.

Keep Reading Show less
popular
Instagram / JLo

The Me Too movement has shed light on just how many actresses have been placed in positions that make them feel uncomfortable. Abuse of power has been all too commonplace. Some actresses have been coerced into doing something that made them uncomfortable because they felt they couldn't say no to the director. And it's not always as flagrant as Louis C.K. masturbating in front of an up-and-coming comedian, or Harvey Weinstein forcing himself on actresses in hotel rooms.

But it's important to remember that you can always firmly put your foot down and say no. While speaking at The Hollywood Reporter's annual Actress Roundtable, Jennifer Lopez opened up about her experiences with a director who behaved inappropriately. Laura Dern, Awkwafina, Scarlett Johansson, Lupita Nyong'o, and Renee Zellweger were also at the roundtable.

Keep Reading Show less
popular

Life for a shelter dog, even if it's a comfortable shelter administered by the ASPCA with as many amenities as can be afforded, is still not the same as having the comfort and safety of a forever home. Professional violinist Martin Agee knows that and that's why he volunteers himself and his instrument to help.

Keep Reading Show less
popular
Courtesy of Macy's

In many ways, 18-year-old Idaho native, Hank Cazier, is like any other teenager you've met. He loves chocolate, pop music, and playing games with his family. He has lofty dreams of modeling for a major clothing company one day. But one thing that sets him apart may also jeopardize his future is his recent battle against a brain tumor.

Cazier was diagnosed in 2015. When he had surgery to remove the tumor, he received trauma to his brain and lost some of his motor functionality. He's been in physical, occupational, and speech therapy ever since. The experience impacted Cazier's confidence and self-esteem, so he's been looking for a way to build himself back up again.

"I wanted to do something that helped me look forward to the future," he says.

Enter Make-A-Wish, a nonprofit organization that grants wishes for children battling critical illnesses, providing them a chance to make the impossible possible. The organization partnered with Macy's to raise awareness and help make those wishes a reality. The hope is that the "wish effect" will improve their quality of life and empower them with the strength they need to overcome these illnesses and look towards the future. That was a particularly big deal for Cazier, who had been feeling like so many of his wishes weren't going to be possible because of his critical illness.

"In the beginning, it was hard to accept that it would be improbable for me to accomplish my previous goals because my illness took away so many of my physical abilities," says Cazier. His wish of becoming a model also seemed out of reach.

But Macy's and Make-A-Wish didn't see it like that. Once they learned about Cazier's wish, they knew he had to make it come true by inviting him to be part of the magical Macy's holiday shoot in New York.

Courtesy of Macy's

Make-A-Wish can't fulfill children's wishes without the generosity of donors and partners like Macy's. In fact, since 2003, Macy's has given more than $122 million to Make-A-Wish and impacted the lives of more than 2.9 million people.

Cazier's wish experience was beyond what he could've imagined, and it filled him with so much joy and confidence. "It is like waking up and discovering that you have super powers. It feels amazing!" he exclaims.

One of the best parts about the day for him was the kindness everyone who helped make it happen showed him.

"The employees of Macy's and Make-A-Wish made me feel welcome, warm, and cared for," he says. "I am truly grateful that even though they were busy doing their jobs, they were able to show kindness and compassion towards me in all of the little details."

He also got to spend part of the shoot outdoors, which, as someone who loves climbing, hiking, and scuba-diving but has trouble doing those activities now, was very welcome.

Courtesy of Macy's

Overall, Cazier feels he grew a lot during his modeling wish and is now emboldened to work towards a better quality of life. "I want to acquire skills that help me continue to improve in these circumstances," he says.

You can change the lives of more kids like Cazier just by writing a letter to Santa and dropping it in the big red letterbox at Macy's (you can also write and submit one online). For every letter received before Dec. 24, 2019, Macy's will donate $1 to Make-A-Wish, up to $1 million. By writing a letter to Santa, you can help a child replace fear with confidence, sadness with joy, and anxiety with hope.

Believe
True
Macy's