You're listening to Shortwave from NPR.
Happy spring, Shortwavers.
I'm producer Hannah Chin, and my NatureQuest buddy Emily Kwong is also here.
Hi, Hannah.
With a story about an age-old question for homeowners.
Namely, should I cut down that big tree in my front yard?
Yeah, to chainsaw.
Or not to chainsaw?
That is the question.
Darcy Hughes lives a few miles north of Seattle Washington and has got this big, towering cedar tree that grows right next to her house.
And right now we've got a few birds up there and a few crows.
Of course, generally pretty peaceful here.
Cedars are evergreens, so all year long this tree casts a long, dappled shadow over her front yard.
Really no direct sunlight comes through these branches at all.
And Darcy wants to know should she keep the tree or cut it down to install solar panels on her roof?
Okay, so really the question should be to solar or not to solar.
Yes.
Now, there are nearly 6 million solar energy installations in the U.S. alone.
And when it comes to home solar, a lot of people make the switch because most public utilities rely on fossil fuels.
Like coal, like natural gas.
Yeah, but Darcy is in this really unique situation because Snohomish County most of its energy comes from hydropower dams.
So 90% of her energy is already carbon free.
Got it.
Wait, so then what's the point of installing solar?
She wants to be self-reliant and it wouldn't hurt to lower her electric bills by making her own energy.
But at what cost?
And is it worth the life of a tree?
So today on the show...
When to make way for solar.
We get into the nitty gritty of how solar works and how to choose a solar system that's right for you.
I'm Hannah Shin.
And I'm Emily Kwong.
And you're listening to Shortwave, the science podcast from NPR.
Okay, Emily, so today we are focusing on a solar crisis.
This is Nature Quest, our series answering environmental questions from listeners like you.
And I guess we got to start with solar panels themselves.
I got to be honest, because I'm a renter, I'm like not totally sure how these work.
I do know I think they're kind of ugly.
Like when I pass them, they look like giant flat screen TVs that are like stuck to the roof.
Fair, but Hannah, I'm going to change your mind because solar panels are actually glorious.
They are the end result of humankind's enduring ambition to harness the power of the sun.
Turning sunlight into electricity.
Scientists of the Bell Laboratories at Murray Hill, New Jersey, demonstrate a solar battery which converts light into power.
These scientists at Bell Labs back in the 1950s used the photovoltaic effect.
Photo as in light, photo and then voltaic.
This is Jenny Heinzen, Master Electrician and the Curriculum Director at the Midwest Renewable Energy Association.
And she went full teacher mode in explaining to me how this photovoltaic effect turns the energy of the sun into an electric current.
So first, you need a material.
And it was Bell Laboratories in New Jersey that figured out.
You could use strips of silicon the same stuff found in sand.
Principal ingredients of ordinary beach sand.
Enough light from a lamp to power this toy Ferris wheel.
Lights on, she works.
Lights off, the motor stops.
Silicon ended up being such an efficient and scalable material that it is what modern solar panels are made out of.
They're very much like computer chips.
They are silicon-based semiconductors.
So basically the solar panel... has a positive side and a negative side.
It's designed that way.
And the positive side is what absorbs the sunlight.
The sun's energy travels as photons.
Those photons, when they hit the solar panel, they knock electrons free.
So then there's all these free electrons, which then travel through the solar panel to the negative side.
And the flow of electrons, as we know, is electricity.
And this process is happening across hundreds of cells on any given solar installation.
And now those electrons are being used to light your house and do your laundry, and make toast and do everything else.
Of course, you need a device to accept these electrons.
A lot of people use solar inverters.
These are magic boxes that convert that direct current into an alternate current.
So if you need more electricity, it pulls from the utility.
If you make extra electricity, that will actually flow back onto the grid to power your neighbors' homes and businesses.
But if the power goes out, lights out.
Wait, so solar doesn't work during a power outage?
No, because the inverter recognizes something is wrong with the grid and shuts down.
So Jenny has seen a lot of people add batteries to their systems as a backup power source.
So that would allow you to truly live off the grid.
Oh, OK.
So now I understand how solar panels work.
Maybe I appreciate them a little bit more than I did before.
But Emily, I still want to know the answer to Darcy's question.
Like, should she cut down the tree to make way for solar panels?
OK, so for this, I wanted to cast a wide net.
I talked to five people in different parts of the country who are all connected to the solar industry.
The five include a journalist, a policy person, a trade person, a master electrician and someone at Darcy's local public utility.
What'd they say?
Ask them all the question, and I expected them to say, you know, break out the chainsaws.
Solar forever.
But instead, I got this.
I would not make that as the first move for sure.
If a tree is shading their home, it's doing a really good thing for them.
I wouldn't cut down a tree that I loved in my yard to do solar.
Maybe this isn't the right answer as a solar advocate.
Wait, okay, this does surprise me that all of them are so...
Yeah, many of them talked about how trees sequester carbon from the atmosphere, which Darcy well knows.
But this point about sequestration is interesting to me because, pound for pound, solar panels are significantly more efficient than trees at offsetting carbon.
And yet everybody begged.
Darcy, unless this tree is sick and rotting and a hazard to your home someday, do not cut it down.
Yeah, I gotta say, this feels like more of an emotional argument rather than a logical argument.
It just doesn't really totally make sense.
Did they explain why?
Yeah, it is a logical argument.
Got it.
Yeah, I'll let John Farrell... at the Institute for Local Self-Reliance, speak his piece.
Having a tree is amazing, and especially if it shades your house and especially if you have high energy bills in summer months.
Trees provide natural cooling, and a sustainable house isn't just about whether you have all the gizmos and the solar panels and the electric car and the heat pump, whatever.
It's also about like your home's natural environment and how much energy it uses.
And a home with more shade is going to use a lot less AC and have to, you know, tap the local utility less.
I mean, I'm from Oregon and my parents and the folks I grew up with have been experiencing really unprecedented heat waves for the past couple of summers.
Plus, a lot of homes in the area, including mine, are older and so they don't have AC.
So the shade that the trees provide is really invaluable.
Yeah, the Pacific Northwest is historically very cool, but it is getting hotter.
And I was reminded of this while talking to Susie Oversvee, who runs solar programs at Darcy's local public utility, Snohomish County, PUD.
We're getting more extreme and more frequent heat events.
And so we are at the utility seeing more and more customers installing air conditioning.
Okay, so because of the shade, don't cut down the tree, end of episode?
Don't cut down the tree, but not end of episode.
There are other pathways for Darcy to explore solar.
I've come up with a three-step plan.
Do you want to hear it?
Yes, I love a three-step plan.
What's step one?
Call up a solar installer and have them come to your house.
Maybe the shade isn't as significant as Darcy assumes.
Solar panels can work in cloudy weather.
Also, there are places besides her roof where she can put panels.
There are ground-mounted systems, pole-mounted systems, even plug-in solar panels.
So you can put them on a balcony.
You can put them in your backyard.
You can hang them from a porch or something like that.
This is Kevin Lucas.
He works for the Solar Energy Industries Association, like the big trade group that represents the solar industry.
The installers can come to their house and look at the trees and determine exactly how much sunlight they get through the year.
And then, with that information, along with the quotes of a couple of different reputable installers, she can make a decision as to whether this makes sense.
I didn't even realize this was something that you could do, basically like phone a trustworthy expert.
Yes, trustworthy is important because NPR's Jeff Brady, who has been covering the solar industry for years now, says there's some high-pressure sales tactics out there.
Okay.
So Jeff suggests finding a local solar installer who's been doing this for a long time.
He likes this website called the Amicus Solar Cooperative for finding that trustworthy local person.
Got it.
So step one, get an expert, call a reputable solar installer.
What's step two?
Okay, if your property is a good candidate for solar...
Break out your calculator because solar installation ain't cheap.
If you're spending 20000 up front to put solar panels on your house, you got to sit down and do some figuring.
Is this going to save me money over the long run?
Jeff says read those contracts carefully before committing to that solar installer.
It's like a long-term relationship.
It's going to last for 20 or 30 years, hopefully.
I heard one person say that most solar panel relationships last longer than most marriages.
So you really want to choose closely who that person is.
And also check if your area has incentives.
So state or local policies that allow you to lower the installation costs or even to offset your energy bill.
Like if you produce energy for the grid, you might get a discount on your electric bill.
Once you build it.
It's there.
It's sitting there.
You've spent the $20,000 and now the fuel is free and you're generating electricity for free.
Right.
Free is a great price.
True.
But Emily, I remember hearing that the Trump administration and the big beautiful bill recently gutted the biggest financial incentives for renewables.
That was the 30% federal tax credit on new solar installations.
Yeah, that cut was made at the federal level and the growth of the solar industry did slow down last year.
And yet, solar still produced 7% of U.S. energy last year.
That was unthinkable to Jeff 20 years ago.
So he told me, even with these cuts, he thinks solar is here to stay.
So basically, we'll see what happens with the solar industry in the future.
Indeed.
But Emily, you said this was a three-step program.
What's your third step for Darcy?
Darcy, third step.
And this is especially if your installer is like, actually, there's no place for you to put solar.
Check out Community Solar.
Basically any shared solar projects.
These are where a group of people finance the installation of solar panels in another place.
It's good for people who rent or people with trees.
Jenny, the electrician, put it this way.
So there's a plot of land and you go in together and you all garden together.
You can do that with solar, solar gardens.
So even if the sun isn't shining directly on your house, it is always shining somewhere.
I love a community solution.
Emily Kwong.
Yeah.
Thank you so much for bringing us this story.
Hannah Chin, you're very welcome.
Short Wavers.
If you like this episode, check out Jeff Brady's recent reporting on plug-in solar panels.
Link it in our show notes.
And be like Darcy.
Send us whatever question you have about your local environment.
Just record a voice memo with your question, and we'll go on a quest.
Email it to shortwave at npr.org.
This episode was produced by me, Hannah Chinn.
And edited by our showrunner, Rebecca Ramirez.
Tyler Jones checked the facts.
Sam Paulson wrote the NatureQuest theme music.
The audio engineer was Robert Rodriguez.
I'm Hannah Chin.
I'm Emily Kwong.
Thanks for listening to Shortwave from NPR.
