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To battle climate change, we’ll need to rapidly move to carbon-free sources of energy. But this technology isn’t a free lunch. They require metals, generate waste and deplete the environment. What’s the best way to balance this shift?
Show Notes
Renewable Energy (DOE)
Fossil Fuels (DOE)
Hydroelectric Power: How it Works (USGS)
China’s Three Gorges Dam: An Environmental Catastrophe? (Scientific American)
Hydropower and Dams – State of Salmon – Problems and Benefits for Salmon (Washington State)
What is a fish ladder? (NOAA)
More than a viral sensation, the Salmon Cannon could bring the species back to the Upper Columbia after 90 years (The Seattle Times)
Where and When to View Salmon – Vancouver Island News, Events, Travel, Accommodation, Adventure, Vacations (Vancouver Island)
LIVE CAM: Brown Bear Cam – Brooks Falls in Katmai National Park (Explore.org)
How An Infamous Hydroelectric Dam Changed Earth’s Rotation (Futurism)
Wind Energy Basics (NREL)
Wind Turbine Blades Can’t Be Recycled, So They’re Piling Up in Landfills (Bloomberg)
Apple expands the use of recycled materials across its products (Apple)
Wind farm weather influence (University of Delaware)
Wind Power and Birds (Audubon Society)
Can Painting Wind Turbine Blades Black Really Save Birds? (Audubon Society)
How Does Solar Work? (DOE)
New Concentrating Solar Tower Is Worth Its Salt with 24/7 Power (Scientific American)
Homeowner’s Guide to Going Solar (DOE)
Transparent solar panels could replace windows in the future. Here’s how (Interesting Engineering)
Solar Roof Shingles Buying Guide For 2022 (Forbes)
Albedo is a simple concept that plays complicated roles in climate and astronomy (PNAS)
Solar panels can heat the local urban environment, systematic review reveals (Physics World)
South Korean 20-Mile Solar Bike Highway Generates Electricity (Interesting Engineering)
That Amazing ‘Solar Roadways’ Project Has a Working Prototype (Bloomberg)
Perovskite Solar Cells (DOE)
Geothermal Basics (DOE)
Iceland drills hottest hole to tap into energy of molten magma (New Scientist)
What Keeps the Earth Cooking? (Berkeley Lab)
Transcript
Transcriptions provided by GMR Transcription Services
Fraser Cain: Astronomy Cast episode 654, “The Side Effects of Clean Energy.” Welcome to Astronomy Cast, our weekly facts-based journey through the cosmos, where we help you understand not only what we know but how we know what we know. I’m Fraser Cain. I’m the publisher of Universe Today. I’ve been a space and astronomy journalist for over 20 years. And with me is Dr. Pamela Gay, a senior scientist for the Planetary Science Institute and the director of Cosmo Quest. Hey, Pamela, how you doing?
Dr. Pamela Gay: I am doing well. My doctors have finally figured out how to treat my pinched nerve. Life is good. Ask me anything. I will probably answer it overly honestly, but the show will go on.
Fraser Cain: This is the drug talking.
Dr. Pamela Gay: Yes. The show will go on.
Fraser Cain: And so the question was asked by someone on your team, was where are you hiding aliens?
Dr. Pamela Gay: You know, I personally am not hiding aliens. I don’t know anyone else who is hiding aliens. But I, too, would like to know, if the aliens have got here –
Fraser Cain: Where are they hiding?
Dr. Pamela Gay: Where are they being hidden?
Fraser Cain: Yes. All right.
Dr. Pamela Gay: I don’t think they’ve gotten here, though.
Fraser Cain: Well, that was our chance. Conspiracy debunked. To battle climate change, we’ll need to rapidly move to carbon-free sources of energy, but this technology isn’t a free lunch. They require metals, generate waste, and deplete the environment. What’s the best way to balance this shift?
All right, Pamela, we’re talking about – last week, we talked about the variables that go into climate change. I think, I hope, everyone was either convinced by your – not necessarily argument, that it’s complicated.
Dr. Pamela Gay: Yes.
Fraser Cain: And today we’re gonna talk about the solutions, which are complicated.
Dr. Pamela Gay: Yes. Yes, they are.
Fraser Cain: Yes. So, if we don’t shift to a carbon-free future, then temperatures will continue to rise and continue to rise as long as we want to keep changing the environment, until we’re incapable of changing the environment anymore because we’re all dead.
Dr. Pamela Gay: Yes.
Fraser Cain: So, at some point we’ve got to make this shift, but if we make the shift sooner, we could cause even potentially more impact than if we do it more slowly, but more sustainably. It’s a weird paradox.
Dr. Pamela Gay: It’s complicated, is going to be the theme of these episodes.
Fraser Cain: It’s complicated.
Dr. Pamela Gay: And part of the problem is every mechanism we have for creating the energy that we use, for the lighting that’s making me not look terrible, for the cameras and the computers and everything else that allows our modern standard of living, that any mechanism for creating that energy is going to have some sort of an impact on the world, and we’re only able to predict what will happen based on the variables we know.
And one of the things that keeps happening is we realize there are unintended consequences for so many of the things that we do.
Fraser Cain: Well, a good example is I live a 100 percent renewable energy lifestyle. No part of my energy comes from fossil fuels. It is 100 percent renewable energy. Water? Dammed. And in order to create the dam that I use to get my power, they flooded a river valley and built a dam and deeply changed the local environment. You can swim in the lake behind the dam, and you see old tree trunks down at the bottom of the lake. It’s a very weird thing to swim around in that.
And we see that on a much larger scale, what happened with the Three Gorges Dam.
Dr. Pamela Gay: Yes.
Fraser Cain: There were entire villages that were flooded.
Dr. Pamela Gay: Archaeological sites.
Fraser Cain: Yes, yes, that are lost. And so even what is arguably the cleanest form of energy still has an impact on the environment.
Dr. Pamela Gay: Yes. It’s really difficult to sort out, and with dams, you have all sorts of weird – we have now completely changed the environment issues, and salmon is one of the big issues that we’ve had to figure out as human beings because in the area of the country you live in, all up and down the Northwest corridor, salmon spend a whole lot of time out in the ocean, but then they come back and swim upriver to their spawning areas. And if there’s a dam along the way, they’re like not gonna spawn here.
Fraser Cain: Yes. Yes.
Dr. Pamela Gay: So, we have to figure out how to get the salmon past the dams so they can go to their spawning areas, and this has meant building what are called salmon ladders, which are essentially staircases with water that –
Fraser Cain: I have them all around me. Yes.
Dr. Pamela Gay: And have you seen the salmon cannons?
Fraser Cain: Yes. Yes. We don’t have salmon cannons here, but we definitely had salmon ladders, and it’s actually pretty cool. Like you have this ladder that goes around the side of the dam, and you can go out and watch the salmon, and they jump high. Like they’ll jump three feet, four feet out of the water into the air and then land back down in the water, and you can actually just watch them jumping up.
I know this is a total diversion here, but we have a salmon hatchery that is really close to where I live, and you can go in there. It’s kind of like an aquarium, so they have these big glass windows you go in, and you can watch the salmon as they’re moving through the facility on their way up the river.
Dr. Pamela Gay: That’s cool.
Fraser Cain: And so some percentage of them, they harvest the eggs and artificially create more salmon, but partly they let a bunch of them through, and you can watch them just swimming past and continuing their way up the river. And we swim in the rivers here when it’s salmon spawning season, and it’s like you’re – well, I mean, you are. You’re swimming in a school of fish, these salmon waiting at the bottom of a series of rapids before they can regain their energy, and you’re surrounded by 1,000 salmon while you’re swimming in the water. You put on your snorkel and mask and swim around all these salmon. It’s kind of an amazing experience.
Dr. Pamela Gay: That’s amazing.
Fraser Cain: Yes, yes. And it’s weird, I never think about it, right? Like it’s just my life, is the autumn stink of dead salmon everywhere, is the ambient – that’s what October smells like, is dying salmon.
Dr. Pamela Gay: The other thing, the salmon are also – this is a trickle-down effect. We have to get the salmon where the salmon are going because the bears need the salmon, and there are amazing video cameras up in Alaska of bears just awkwardly eating salmon because bears are awkward athletes.
Fraser Cain: Yes.
Dr. Pamela Gay: And so there’s the entire – all the critters that eat the salmon, and so in order for us to get electricity, we have to figure out how not to starve the bears.
Fraser Cain: Right, right. Well, and even like – clearly, as a West Coast Canadian, I know way too much about this, but if they increase the flow for hydroelectricity out of the dam, it washes out the salmon spawning sites, and so they always have to have this balance where they are letting the water out, but they can’t let the water out too fast. And so when there’s a flood, they will not let the water out too fast, and instead we get flooding downstream because they don’t want to wreck the salmon habitats and let the water out.
So, it’s this management. It’s this constant management, is what you’re dealing with. So, anyway –
Dr. Pamela Gay: And the flooding is upstream.
Fraser Cain: Yes, yes, yes. So, they balance the flooding across the entire river to minimize the impact on the salmon stream, on the spawning beds. It’s a whole balance.
But yes, so this is one example, right? And this is, I would say, probably the cleanest form of energy that’s out there, and yet it has all kinds of consequences that you have to consider.
Dr. Pamela Gay: Down to changing the rotation rate of our planet.
Fraser Cain: But dams change the – I guess so.
Dr. Pamela Gay: So, the Three Gorges Dam actually changed the moment of inertia for our planet by causing a massive pile-up of water behind the dam, and by changing the planet’s moment of inertia, it changed its rotation rate. And there are a whole lot of students very glad I’m no longer teaching physics because that would be a homework problem.
Fraser Cain: Calculate the moment of inertia. That’s awesome. All right. So, let’s talk about some of – we’ve talked about hydroelectric dams, but let’s talk about some of the other clean energy possibilities and what their side effects are.
Dr. Pamela Gay: So, the one I think that I literally see the most is wind farms. One of the most amazing things I’ve seen is flying from London to Amsterdam. That part of the North Sea is filled with wind turbines out in the ocean. They also have them off the coast of Cape Cod. Driving east out of Denver, you hit just like vast swaths of nothing except the occasional rest stop and wind farms as far as the eye can see. And this is a growing way of producing electricity all across the globe. Wind is one of those constants that kind of all of us get a little bit of.
Fraser Cain: And I mean, what are the side effects of producing your energy with the wind?
Dr. Pamela Gay: So, here it’s not just the producing it with the wind that we run into. It’s the mechanism of producing it with the wind that we run into. So, it turns out that the materials that they make wind turbines out of aren’t entirely recyclable, and there’s a lot of trouble with, okay, so this wind turbine bit the dust. We need to replace the entire structure. The thing got damaged in a wind storm, got damaged by lightning, got damaged by whatever.
And we don’t have a good way of dealing with this waste product, and these things are huge.
Fraser Cain: Yes.
Dr. Pamela Gay: Now, this is at least a problem that hopefully will eventually be solvable. It’s something that requires creativity and a mechanism to figure out how to ship the turbines in a cost-effective manner. That really is proving to be one of the difficulties of you have this massive piece of trash, and inevitably you’re not going to need nearly as many recycling places in this country as there are places with wind turbines in this country, so a lot of them are just gonna end up in the nearest dump. And that is actually a problem that isn’t really getting talked about.
Fraser Cain: And you see, I mean, when you buy an iPhone today, the thing is almost entirely recyclable. The guys put a lot of energy into getting their phones to be recyclable to some extent. And so they’re just big electronic devices, but also with steel and carbon fiber and things like that, and you can imagine we’ll get to a point where these things are cradle-to-grave recycled, as they break. And they might be maybe less efficient in their energy production, but they’re more energy efficient over the long term by being able to reuse the components as they break down. It is definitely a challenge.
Dr. Pamela Gay: Right.
Fraser Cain: Now, what about the amount of wind? Like, as you put more and more wind farms out there, are you actually starting to change weather patterns?
Dr. Pamela Gay: Yes. There are some really interesting research papers on this, looking at if you reduce the wind, you reduce the planet’s ability to redistribute heat, and how does that overall affect the climate? And it’s looking like right now, with the best models they have, this has the potential to increase the planet’s temperature by 0.28 degrees. So, the question becomes is that increase from wind greater than the increase that would come from burning fossil fuels, from all the other mechanisms that we’re currently using?
It’s hard to balance out, and there needs to be discussion. And wind turbines themselves aren’t entirely innocent in how they treat the environment. There have been a lot of problems with – it’s hard to tell how fast something that big is turning. It looks slow, and it’s not. And birds are called bird-brained for a reason, and they will try and fly through these turning turbines, and it’s not good.
Fraser Cain: Yes, and there’s been a lot of bird kills. Like, they’re killing millions of birds.
Dr. Pamela Gay: Yes. Yes.
Fraser Cain: Yes. And then like again, I mean, hopefully there’s some kind of solution in terms of sound or in some kind of site, or maybe magnetism that will shift them away, or smells, who knows what it is. But there’s got to be some solution to that.
Dr. Pamela Gay: What they’re saying to a certain degree is birds that have certain migratory paths are surviving better than ones that don’t, and so we just need to figure out how to grow the birds on the healthier migration paths.
Fraser Cain: Right, right. Let’s talk about solar.
Dr. Pamela Gay: All right. Solar is fun. So, with solar, there’s so many different forms of solar. I clearly am going to describe a lot of things based on how you see them from airplanes. If you’re flying into LA on just the right flight, you will go over a solar – I’m trying to figure out – they’re heating up sodium.
Fraser Cain: Right. It’s a solar concentration plant.
Dr. Pamela Gay: Yes. And so they have these rings of mirrors that are all shining their light up into this collector, and the heat from this is heating up sodium, and this is generating electricity. So, there’s that form of solar that we don’t talk about because it’s still experimental, but it’s super cool looking. It looks like a flower of mirrors from overheard. So, you get pretty energy this way.
But the most common way that we’re seeing solar electricity is your good old-fashioned generic solar panel. There are companies that are currently working on technology to make windows that can be seen through from one side but not the other, that at a low level are capable of collecting solar energy. There are companies working on creating tiles for roofs so instead of having a slate roof, you now have a solar-paneled roof. I love this idea. The technology is not quite there, but the next time we reroof our house, I suspect we’re gonna do it with solar tiles.
Fraser Cain: Now, the side effects, like you’re dealing with obviously the amount of – I mean, they’re electronics.
Dr. Pamela Gay: Yes.
Fraser Cain: They’re e-waste in the same way that you are throwing away your computer, you’re throwing away all of that e-waste. When you get rid of your phone, you’re getting – you know, and they’ve got heavy metals in them, they’ve got – they are essentially electronics.
Dr. Pamela Gay: Yes, and they also change the albedo of the planet.
Fraser Cain: Well, and that’s what I was gonna ask, is do they actually change –
Dr. Pamela Gay: Yes.
Fraser Cain: Because I guess having regions that are dark and absorbing sunlight will change the heat absorptivity? Absorption? Of the planet.
Dr. Pamela Gay: So, I’m just gonna go with albedo.
Fraser Cain: Yes, fine, use a science term.
Dr. Pamela Gay: But it’s not quite the right word. So, normally you look at a highway, you have this nice black asphalt. The nice black asphalt absorbs all of this heat, and then it re-radiates it as thermal energy, adding to the greenhouse effect. You put solar panels along the center of the highway and put bike trails under it, where they are nicely shaded and protected from the cars. Please do more of this. This is happening in Korea.
These black solar panels, however, are absorbing all of this heat and going, “Ha ha! I shall create energy instead of re-radiating it as infrared!” And I love the fact that you have this black thing that instead of re-radiating and adding to the energy crisis, is generating electricity.
So, a lot of folks are trying to figure out – and solar panels are still so fragile, and this is the problem with them. They’re trying to figure out how to create solar walkways, solar roads, and there’s been some really interesting trials in Scandinavia where they have actually created roads that light up different things to tell you the weather conditions.
Fraser Cain: I’m gonna call bogus on that. That tech is not –
Dr. Pamela Gay: It doesn’t work yet. Consistently.
Fraser Cain: Doesn’t work. It is not even ever.
Dr. Pamela Gay: It is an experiment.
Fraser Cain: I wouldn’t even go so far as to call it an experiment. It is pretty half-baked at this point. Like there’s nothing better than just a great big solar panel that is gathering the heat. Those will – I know what you’re talking about, and –
Dr. Pamela Gay: I want smart roads. I want smart roads.
Fraser Cain: Yes. Well, hey, we all do. Who wouldn’t love smart roads? The technology that I’m super into is perovskite. So, I don’t know if you’ve ever heard of the term. Perovskite is another –
Dr. Pamela Gay: I have.
Fraser Cain: Yes. It’s another kind of solar film technology. It is a fraction of the price, way cheaper. You can paint it. You can just take any surface you want and just paint perovskite onto that surface, and it will turn into a big solar panel.
The downside of it is that it is highly reactive with the oxygen in the atmosphere, and it ruins it.
Dr. Pamela Gay: Yes, I was gonna say, it works great in space.
Fraser Cain: It works great in space. Well, they’re still testing this out. They think it’s gonna work great in space, that you could paint the Moon and have a giant solar panel, or you could paint your space station, or whatever. But in the atmosphere, you’ve got to protect it from the atmosphere or it’s ruined almost instantaneously. But people are figuring out ways to do that.
But then you can imagine, it’s gonna have chemicals. It’s gonna produce chemicals into the atmosphere. Maybe it’s gonna make microplastics, who knows. But I’m really excited by having a kind of technology that you can just easily paint onto anything. Your car, your road. It may be less efficient than the really fancy glass panels, but you will just cover more stuff with this perovskite solar panels. And so I feel like we’re just this side of a revolution as well.
All right, let’s talk about the two other renewable technologies that I want to talk about. The first is geothermal.
Dr. Pamela Gay: Yes. Geothermal is super cool, and there’s been some really weird experiments in Iceland where they have done very careful basically tunneling down to essentially magma, to create systems where they can heat water this way and they cycle water. And some of the experiments have generated a whole lot of earthquakes, but Iceland is kinda used to that, so they move on, it’s all good.
Most of the experiments with geothermal are more along the lines of anyone who’s ever gone down into a mine has experienced it. It gets colder, colder, oh my God it’s getting hotter, hotter, hotter. And this is that transition from – and getting colder because the Sun hasn’t heated up the soil. This is why basements in houses are often cool. To getting deep enough that you’re starting to experience the added heat of our planet that comes from not just the heat of the core, but also from all of the radioactive decays that are taking place within our planet. And so it gets kind of warm, and it’s really – I’m gonna understate it.
Fraser Cain: Yes, yes, kind of.
Dr. Pamela Gay: There are some really cool things done where like I once visited a high school that was focused on training people for technical jobs that don’t require a university, and this high school had a full geothermal setup powering the entire high school, where they were essentially just cycling water down to great depths and then bringing it back up.
Fraser Cain: Right.
Dr. Pamela Gay: And that heat was able to drive power. It was really cool.
Fraser Cain: Now, the other idea – I mean, you’re talking about like the geothermal power that’s in Iceland, where the water is relatively close to the surface.
Dr. Pamela Gay: Yes.
Fraser Cain: But this idea of deep rock geothermal, that you can run your geothermal down to 10 kilometers down, you could run a geothermal plant anywhere, taking advantage of that heat that you mentioned. But you only get to use that mine for a little while until you’ve extracted all of the heat from that area. So, are we gonna cool down planet Earth by using geothermal energy?
Dr. Pamela Gay: I think it’s a reversible kind of situation because the world that we’re on is going to continue generating new geothermal. So, if we cool off a volume, the volume around it on all sides is still doing the whole generating heat, generating heat, generating heat thing at a constant rate, ish. And so if we cool off a specific volume because we’re able to extract heat from it faster than it is producing heat or gaining heat from the volumes around it, once we stop extracting heat, it will over time warm back up.
Understanding the thermodynamics of how quickly that’s able to happen, how quickly we’re able to return to an equilibrium once we stop extracting heat – this isn’t a permanent solution. It’s the kind of thing where in Iceland, perhaps you’re going to remove energy that would otherwise go into an erupting volcano, and that’s a good thing.
Fraser Cain: Right. Yes.
Dr. Pamela Gay: But outside of like Italy and Japan and Iceland and these hyper-volcanic places –
Fraser Cain: Pacific Northwest.
Dr. Pamela Gay: Yes. You’re going to run into this what is your equilibrium time. How fast can the area return back to where it was before you started extracting the energy.
Fraser Cain: All right, let’s talk about one last type of clean energy, and that is nuclear.
Dr. Pamela Gay: Oh. The giant elephant in the room.
Fraser Cain: Yes. What are the side effects of nuclear energy?
Dr. Pamela Gay: Well, if your plant loses power because the area is getting bombed by Russia, you run the risk of exploding and taking out a large section, through your meltdown, of Europe.
Fraser Cain: Yes.
Dr. Pamela Gay: Not that that might not be something that could possibly happen right now in Ukraine. So, nuclear is one of those things where it is entirely safe if you do it right, and human beings are fallible. And so technology today makes it so that we can create really, really safe power plants. Really safe nuclear power plants, as long as they’re using state-of-the-art technology to control the safety systems.
Fraser Cain: Yes.
Dr. Pamela Gay: There is nuclear waste. Depending on what it is, you can take waste from one kind of reactor and turn it into power in another kind of reactor. Breeder reactors are really good at doing this. You ultimately are always going to end up with some sort of a by-product, and I keep hoping that we’re gonna find more interesting ways to use these by-products because these by-products are generating heat. They’re just also generating like radioactive particles.
Fraser Cain: Radioactive particles, yes.
Dr. Pamela Gay: That could kill us.
Fraser Cain: Yes, yes.
Dr. Pamela Gay: So, that’s a problem I just want us to solve, and we haven’t yet, and I’ve been waiting for us to solve it since –
Fraser Cain: Can’t we – like the point here, I think, is like we know we have to get off the carbon technologies.
Dr. Pamela Gay: Yes.
Fraser Cain: We have to shift to some combination of the technologies that we mentioned. Each one is gonna work in terms of are they base load, are they not base load, do they work in your situation. Obviously here, hydroelectric, we can just run all the hydroelectric we want, and we wouldn’t need a nuclear plant here on Vancouver Island, while you in the middle of the US might need a nuclear plant, or some combination of solar or whatever. We have to face the downsides of these technologies and adopt them anyway because the consequences of not adopting them are worse.
Dr. Pamela Gay: Yes. And it ultimately comes down to a balancing act.
Fraser Cain: Yes.
Dr. Pamela Gay: Nuclear power adds heat to the planet. Hydroelectric changes ecosystems in massive ways. Solar removes heat from the environment. I’m a fan. We have to figure out how to balance it all out, and the “it’s complicated” comes in because we’re still learning all of the variables involved. This is going to be a constant dance of trying to figure out things for the next generation, and that’s how long we have, is a generation.
Fraser Cain: I mean, I find this stuff exciting.
Dr. Pamela Gay: Yes.
Fraser Cain: I personally really enjoy solving problems. I love technology, I love using technology to solve my problems, and I find the tracking this stuff and watching as it changes – you know, I love, I’ve mentioned this before. Like I love my electric car, and even if my electric car polluted the environment more than a gas car, I would choose the electric car for its features. I’ve just got like an old used Nissan Leaf, but it’s the greatest.
And I think that for a lot of people, they’re afraid of these new technologies. And yet once you start to implement them and use them in your life, you’re like, “This is the best. I never want to go back to a gas-powered lawnmower,” right? Like, a battery-powered lawnmower is the greatest.
So, we’re running out of time, so I think we should wrap here. But on that note, compromise, adapt, be aware of the downsides, minimize our impact on the environment, and move forward. Thank you, Pamela.
Dr. Pamela Gay: Yes. Thank you, Fraser, and thank you to all of our patrons on Patreon.com/astronomycast. You allow the show to go on. I now have names to read for a whole group of you. So, this week I’m going to read the names of Simon Parton, Kellianne and David Parker, Jeremy Kerwin, Stuart Mills, Rob Cuffe. Thank you for putting pronunciation guide in. Harald Bardenhagen, Justin Proctor, Alex Cohen, Matthew Horstman, Rando, Phillip Walker, marco iarossi, Daniel Loosli, David Gates, Scott Kohn, Scott Bieber, Claudia Mastroianni, Jim Schooler, Nial Bruce, Kseniya Panfilenko – I like you, please put in the pronunciation guide.
Matthias Heyden, The Lonely Sand Person, Gregory Singleton, Jeff Willson, Disasterina, Tim McMackin, William E Kraus, Cooper, Steven Shewalter, Alex Raine, Omar Del Rivero, Benjamin Müller, Allan Mohn, Paul D Disney, Eran Segev, Kenneth Ryan, Micheal Regan. And if you want to know how to pronunciation guide it, change your last name to have your last name (pronounced as), and I will love you even more.
Thank you all. You make this happen.
Fraser Cain: Thanks, everyone. We’ll see you next week.
Dr. Pamela Gay: Bye bye.