WEBVTT - How Solar Towers Work

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<v Speaker 1>Can technology with box Stuff from hastuftfom. Hey there, and

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<v Speaker 1>welcome to tech Stuff. I am your host, Jonathan Strickland,

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<v Speaker 1>and today I thought I would look back on a

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<v Speaker 1>topic that we've covered a few times on Tech Stuff

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<v Speaker 1>in multiple ways, and that's solar power. So we've talked

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<v Speaker 1>about solar power and lots of different episodes. We covered

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<v Speaker 1>the unlikely solar freaking roadways, which we felt were uh,

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<v Speaker 1>unrealistic is probably the best way I can describe that

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<v Speaker 1>in our opinion, and then we also talked about the

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<v Speaker 1>solar Impulse airplane. We've talked about solar panels and their efficiency.

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<v Speaker 1>Today I want to talk a little bit about solar towers,

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<v Speaker 1>which is a different way of harnessing the Sun's energy,

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<v Speaker 1>and I think it's a really clever way as well,

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<v Speaker 1>because it doesn't rely on sunlight hitting a panel. Obviously,

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<v Speaker 1>the big big drawback to that approach is when the

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<v Speaker 1>sun isn't hitting a panel, you're not generating any electricity. Right,

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<v Speaker 1>So if it's super cloudy or if it's nighttime, if

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<v Speaker 1>the sun is not able to hit the panel, the

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<v Speaker 1>sunlight is not getting there, you have nothing to convert

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<v Speaker 1>into electricity, and your solar panels go on to be

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<v Speaker 1>unused for that duration, so that can be really rough

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<v Speaker 1>if you have a long stretch of overcast days, or

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<v Speaker 1>you live in a place where you don't get solar

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<v Speaker 1>exposure at your house because of maybe they're taller buildings

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<v Speaker 1>around you, or trees or whatever it may be. Maybe

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<v Speaker 1>you have a north facing house rather than a south

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<v Speaker 1>facing house here in the Northern Hemisphere. If you have

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<v Speaker 1>a south facing house in the Northern Hemisphere, you're going

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<v Speaker 1>to get more solar exposure than a north facing house,

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<v Speaker 1>So solar panels have that drawback there. Also, there's efficiency

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<v Speaker 1>issues with solar panels. When we talk about efficiency, what

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<v Speaker 1>we mean is how much of the sun's energy can

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<v Speaker 1>we actually convert into electricity and how much of it

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<v Speaker 1>do we lose? How much of that energy bounces off

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<v Speaker 1>the panel and we do not capture it. Most commercial

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<v Speaker 1>solar panels, the kind that you would put on your house,

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<v Speaker 1>the efficiencies around eleven, meaning that you're losing a lot

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<v Speaker 1>of that energy not is not converting into electricity. What

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<v Speaker 1>that means is that you have to buy more solar

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<v Speaker 1>panels to cover more space, to collect more solar energy,

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<v Speaker 1>to generate enough electricity to meet your needs. Obviously, if

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<v Speaker 1>solar panels were efficient, which is impossible, by the way,

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<v Speaker 1>physically impossible. People have proved it with math. Then if

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<v Speaker 1>you if it were a hundred percent efficient, you wouldn't

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<v Speaker 1>need as many solar panels in order to do what

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<v Speaker 1>you need to do. That's just not the case in reality,

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<v Speaker 1>so instead we often have to buy more than what

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<v Speaker 1>we would cover a larger area. And even then again

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<v Speaker 1>you're limited to collecting electricity or generating electricity i should say,

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<v Speaker 1>during the daylight hours. And electricity also is a use

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<v Speaker 1>it or lose it kind of thing, meaning that if

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<v Speaker 1>you don't have an immediate use for that electricity and

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<v Speaker 1>you don't have a way to store it, you lose

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<v Speaker 1>that electricity. You have to use it when it's generated,

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<v Speaker 1>So you need to have some sort of battery system

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<v Speaker 1>as well, so that in the times when you're not

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<v Speaker 1>using the electricity you're generating, you can still save it

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<v Speaker 1>for later use. And until recently, batteries have been really

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<v Speaker 1>expensive for the home, but Tesla's power wall has kind

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<v Speaker 1>of led a revolution in that space, and we're starting

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<v Speaker 1>to see more affordable versions of batteries hit the home market. Okay,

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<v Speaker 1>all of that's out of the way to just say

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<v Speaker 1>that the traditional solar panel approach has its drawbacks. Now,

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<v Speaker 1>let's talk about solar towers, because they take a totally

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<v Speaker 1>different approach to harnessing electricity from the sun, and it's

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<v Speaker 1>really pretty clever, and they can harness electricity or they

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<v Speaker 1>can generate electricity day or night. So you might wonder,

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<v Speaker 1>how is that possible when when the Earth rotates so

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<v Speaker 1>that the sun is no longer shining on a solar tower,

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<v Speaker 1>where is that electricity coming from? So here's the way

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<v Speaker 1>it works. Now. I'm largely going to refer to a

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<v Speaker 1>company called Solar Reserve, which is here in the United States.

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<v Speaker 1>Solar Reserve is just one company that is building structures

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<v Speaker 1>like these around the world, So I don't mean to

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<v Speaker 1>suggest they're the only one. I'm using them as the

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<v Speaker 1>example because that so much of their information is available

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<v Speaker 1>to actually read about and understand. So it's a really

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<v Speaker 1>helpful approach. Solar towers. Well, first of all, the name

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<v Speaker 1>kind of gives away the main feature. There's a tower

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<v Speaker 1>at the center of this, uh structure or really multiple structures.

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<v Speaker 1>So how tall are these towers? Will? According to solar reserve.

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<v Speaker 1>The height of the tower and it's thermal risk fiver

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<v Speaker 1>more on that in just a second. Tends to be

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<v Speaker 1>sixty feet combined or about one So you've got this

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<v Speaker 1>tower in a a large area. You want to have

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<v Speaker 1>an area that gets a lot of solar exposure, otherwise

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<v Speaker 1>this is not a practical way of generating electricity. So

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<v Speaker 1>imagine like a desert, nice flat desert, lots of sunlight

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<v Speaker 1>hitting that desert every typical day, and you have a

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<v Speaker 1>tall tower with a receiver on the top of it.

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<v Speaker 1>Now that receiver is actually a series of dark panels.

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<v Speaker 1>And these aren't solar panels, not in the way that

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<v Speaker 1>you would put on top of your house. They are

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<v Speaker 1>not converting sunlight into electricity directly. Rather, they are panels

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<v Speaker 1>that transfer thermal energy. In other words, they're all about

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<v Speaker 1>transmitting heat. So these panels have sixty six thin wall

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<v Speaker 1>straight tubes in them. Those tubes are designed to conduct

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<v Speaker 1>heat from the outside to the inside of that tower.

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<v Speaker 1>And the tubes are made out of a steel alloy

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<v Speaker 1>that's covered in a high absorptivity black coating to maximize

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<v Speaker 1>the amount of energy the panel can absorb. So you've

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<v Speaker 1>got sunlight shining on this tower. Well, how is that

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<v Speaker 1>enough to generate electricity on its own. It's not. In fact,

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<v Speaker 1>what you end up doing is surrounding the tower with mirrors. Now,

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<v Speaker 1>Solar Reserve uses mirrors that they call heliostats. These heliostats

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<v Speaker 1>are mounted on h arms essentially that allow them to

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<v Speaker 1>track the motion of the sun. That way, the mirrors

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<v Speaker 1>maintain the ideal angle to uh to reflect the Sun's

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<v Speaker 1>light directly towards the top of that tower at that

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<v Speaker 1>receiving point of the tower on those panels. And we're

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<v Speaker 1>talking about a lot of mirrors. Solar Reserve has one

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<v Speaker 1>area it's called the Crescent Dunes that's there there um

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<v Speaker 1>tower or that they have in the US, and the

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<v Speaker 1>Crescent Dunes towers surrounded by more than ten thousand mirrors

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<v Speaker 1>covering a fifteen hundred acre field. So this is a

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<v Speaker 1>big operation. You've got to have a lot of open

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<v Speaker 1>land for this to work. That's obviously one of the

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<v Speaker 1>potential drawbacks, right that you need a place that's going

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<v Speaker 1>to have a lot of solar exposure and you need

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<v Speaker 1>to have enough space to make it makes sense. But

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<v Speaker 1>assuming you have both of those things, you can do

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<v Speaker 1>something pretty incredible. So what these mirrors do is direct

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<v Speaker 1>that sunlight up at those dark panels I was talking about.

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<v Speaker 1>Remember I mentioned there were fourteen. These fourteen panels are

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<v Speaker 1>divided up into two groups of seven. Each group of

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<v Speaker 1>seven represents kind of a circuit, and that circuit is

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<v Speaker 1>not for electricity. It's rather for a circuit of pipes

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<v Speaker 1>that are circulating liquid salts. So liquid salts are pretty cool, uh,

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<v Speaker 1>which is a weird way of putting it when you're

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<v Speaker 1>talking about thermal energy. But liquid salts can hold on

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<v Speaker 1>to more heat than water can and can remain in

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<v Speaker 1>liquid form, so in other words, they don't vaporize into steam.

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<v Speaker 1>And what solar reserve does is it pumps around five thousand,

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<v Speaker 1>eight hundred gallons of liquid salts per minute through the

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<v Speaker 1>receiver circuits that run back and forth across the inside

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<v Speaker 1>of these black panels. So imagine you've got this really

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<v Speaker 1>tall tower. At the top of the tower, you have

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<v Speaker 1>these fourteen dark panels, and then let's just take seven

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<v Speaker 1>on one side. You've got seven of those dark pounds

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<v Speaker 1>on one side. On the inside of those panels, you

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<v Speaker 1>would see this criss crossing of a pipe that is

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<v Speaker 1>circulating liquid salts through the pipe. Heat from the outside

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<v Speaker 1>comes into the tower and it begins to heat those

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<v Speaker 1>liquid salts running through that circuit. It's a simple heat transfer.

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<v Speaker 1>And if you've listened to our podcasts about things like refrigera,

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<v Speaker 1>raiders and air conditioners, you know about you know how

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<v Speaker 1>this what the principles are, how how this is based

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<v Speaker 1>same basic thing. You want to give as much surface

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<v Speaker 1>area you know you want to you want to dedicate

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<v Speaker 1>as much surface area as you can to heat and

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<v Speaker 1>have the liquid salts cross over as much of that

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<v Speaker 1>surface area as as possible to heat up the liquid salts.

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<v Speaker 1>As the liquid salts move through the circuit, they become molten,

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<v Speaker 1>so incredibly high temperatures. So the low side of the

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<v Speaker 1>temperatures for these liquid salts is five fifty degrees fahrenheit

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<v Speaker 1>or two degrees celsius. That's the low end. That's that's

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<v Speaker 1>the chili side. If you want to talk about how

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<v Speaker 1>hot they get, they can get up to a thousand

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<v Speaker 1>fifty degrees fahrenheit or five hundred sixty six degrees celsius.

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<v Speaker 1>That's really impressive. And so you've got this massive amount

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<v Speaker 1>of stored thermal energy. It's all inside the molten salts.

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<v Speaker 1>So you've got a lot of heat stored up. What

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<v Speaker 1>good is heat, Well, you can use heat to do

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<v Speaker 1>the same thing that is done in power plants all

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<v Speaker 1>over the world. You use heat to turn water into

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<v Speaker 1>steam and use the steam to turn a turbine, which

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<v Speaker 1>generates electricity. It's an incredibly simple idea. It's the basis

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<v Speaker 1>of almost every other type of power plant, with the

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<v Speaker 1>exception of things like solar panels that are used in

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<v Speaker 1>solar farms. Like that, that's generating electricity straight from sunlight,

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<v Speaker 1>as opposed to using that electricity to somehow turn water

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<v Speaker 1>into steam. That would be ridiculous. You would lose way

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<v Speaker 1>too much energy in that approach. But things like coal

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<v Speaker 1>fired plants, even nuclear power plants, you're talking about generating

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<v Speaker 1>electricity by heating up water into steam and using that

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<v Speaker 1>steam to turn a turbine to do work, and that

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<v Speaker 1>turbine ends up being an electric generator and you get

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<v Speaker 1>electricity from that. So the the purpose of the solar

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<v Speaker 1>tower is really just to collect heat. That's it. It's

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<v Speaker 1>not doing anything magical. It's just generating tons and tons

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<v Speaker 1>of heat. I know that tons is not really a

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<v Speaker 1>unit when it comes to heat or temperature. But you

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<v Speaker 1>understand what I mean. It creates an enormous amount of heat,

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<v Speaker 1>and the molten salts then go into a big storage tank.

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<v Speaker 1>And it's pretty cool because that storage tank u ends

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<v Speaker 1>up being a a way of holding onto the heat

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<v Speaker 1>for a long time. According to Solar Reserve, the company

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<v Speaker 1>says that the molten salt only loses one degree of

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<v Speaker 1>fahrenheit or about point five five five, etcetera, etcetera degrees

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<v Speaker 1>celsius in heat per day. So, in other words, if

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<v Speaker 1>you have a long stretch of overcast days, you still

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<v Speaker 1>have this massive that really tank. It's not a vat,

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<v Speaker 1>it's a tank because it's completely enclosed of molten salts

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<v Speaker 1>and they hold onto that heat, which means you can

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<v Speaker 1>continuously pump that through your water tank in order to

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<v Speaker 1>heat water up to and when I say pump, you

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<v Speaker 1>pump it through. It's a very similar circuit that you

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<v Speaker 1>would find at the top of the receiver. The molten

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<v Speaker 1>salts don't mix with the water. Instead, you have a

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<v Speaker 1>pipe that runs through the water tank. The molten salts

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<v Speaker 1>run through the pipe and transfer some of their heat

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<v Speaker 1>to the water through the material of the pipe. Itself,

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<v Speaker 1>so you're not laying the molten salts in the water

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<v Speaker 1>mixed together. That would be ridiculous. Instead, you're having the

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<v Speaker 1>molten salts move through a pathway and as they move

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<v Speaker 1>through that pathway, they heat up the water. The water turns,

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<v Speaker 1>the steam turns the turbine. Then the steam goes through

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<v Speaker 1>a condenser to condense the steam back into water and

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<v Speaker 1>it goes back into the water tank. So once you

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<v Speaker 1>use the molten salts to transfer some of this heat,

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<v Speaker 1>they they've lost that thermal energy. They're now moving into

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<v Speaker 1>a different tank. It's a tank to pump the liquid

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<v Speaker 1>salts back up into the top of the tower. So

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<v Speaker 1>the neat thing with this system is that you can

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<v Speaker 1>use it to deliver electricity day or night. You've got

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<v Speaker 1>so much stored heat. After you get the system up

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<v Speaker 1>and running and it's generated enough molten salt, like it's

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<v Speaker 1>created enough molten salt through this process to allow this

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<v Speaker 1>to happen, you can deliver electricity on demand twenty four

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<v Speaker 1>hours a day. And that's how all power plants work.

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<v Speaker 1>They deliver electricity on demand. They're not uh set to

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<v Speaker 1>a certain level, and then if you don't meet that level,

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<v Speaker 1>they you know, just that electricity goes to waste. They

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<v Speaker 1>base it upon what the current demand. And I don't

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<v Speaker 1>mean that as a pun, but it came out of

0:13:36.600 --> 0:13:39.559
<v Speaker 1>that way. Chris would be so proud. They don't. They

0:13:39.559 --> 0:13:43.280
<v Speaker 1>respond to whatever the the demand is at that time

0:13:43.559 --> 0:13:48.480
<v Speaker 1>to produce the amount of electricity needed. So super interesting

0:13:48.480 --> 0:13:51.760
<v Speaker 1>way of doing this by using the sun as an

0:13:51.840 --> 0:13:55.679
<v Speaker 1>energy source to create the heat needed to turn water

0:13:55.760 --> 0:13:58.400
<v Speaker 1>into steam and turn a turbine, as opposed to a

0:13:58.440 --> 0:14:02.120
<v Speaker 1>fossil fuel like coal or oil, or a nuclear fuel

0:14:02.200 --> 0:14:04.520
<v Speaker 1>in the case of nuclear fusion. Now, if we ever

0:14:04.800 --> 0:14:08.120
<v Speaker 1>are fission, I should say nuclear fission. I know all

0:14:08.160 --> 0:14:09.920
<v Speaker 1>of you were ready to write in, and you should

0:14:09.960 --> 0:14:13.240
<v Speaker 1>be because that was a silly mistake I made nuclear fusion.

0:14:13.280 --> 0:14:16.679
<v Speaker 1>If we ever cracked that nut, solar towers may seem

0:14:16.760 --> 0:14:21.040
<v Speaker 1>quaint in comparison, but that's a very difficult problem in

0:14:21.080 --> 0:14:23.880
<v Speaker 1>physics to to solve. So we're still waiting on that.

0:14:24.520 --> 0:14:27.680
<v Speaker 1>So the neat thing about this, obviously is that if

0:14:27.720 --> 0:14:30.040
<v Speaker 1>you do have that amount of space, you can really

0:14:30.080 --> 0:14:33.880
<v Speaker 1>offset a lot of a community's electricity needs with a

0:14:33.920 --> 0:14:38.400
<v Speaker 1>solar tower. And uh, the company thinks that the lifespan

0:14:38.440 --> 0:14:41.720
<v Speaker 1>of these solar towers is somewhere in the area of

0:14:41.760 --> 0:14:45.640
<v Speaker 1>about thirty years, meaning that after thirty years you would

0:14:45.640 --> 0:14:48.440
<v Speaker 1>have to start to replace parts because just of wear

0:14:48.440 --> 0:14:52.560
<v Speaker 1>and tear, or they would not be as uh efficient

0:14:52.840 --> 0:14:55.920
<v Speaker 1>as they had previously been. So, for example, those panels,

0:14:56.480 --> 0:14:59.960
<v Speaker 1>if the panels become less efficient at transferring heat over time,

0:15:00.600 --> 0:15:03.200
<v Speaker 1>you would definitely want to replace them because you would

0:15:03.360 --> 0:15:06.840
<v Speaker 1>be transferring less heat to generate your your molten salts

0:15:06.840 --> 0:15:08.720
<v Speaker 1>will be at a lower temperature. It would require more

0:15:08.760 --> 0:15:13.160
<v Speaker 1>of them to turn water into steam. It become less

0:15:13.160 --> 0:15:17.360
<v Speaker 1>efficient overall, So you have to make sure that uh

0:15:17.440 --> 0:15:20.320
<v Speaker 1>you're all the parts are working very they're very few

0:15:20.360 --> 0:15:22.800
<v Speaker 1>moving parts, which is awesome, but you have to make

0:15:22.800 --> 0:15:26.360
<v Speaker 1>sure they're working throughout the lifetime of the facility and

0:15:26.400 --> 0:15:29.840
<v Speaker 1>then obviously replace parts as needed. So the question then

0:15:29.880 --> 0:15:34.760
<v Speaker 1>becomes doesn't make financial sense to switch over to using

0:15:34.800 --> 0:15:38.880
<v Speaker 1>solar towers at least to offset electricity generation in a

0:15:38.880 --> 0:15:42.080
<v Speaker 1>particular area. To answer that question, you have to look

0:15:42.120 --> 0:15:44.920
<v Speaker 1>at a lot of different factors and it is way

0:15:44.960 --> 0:15:48.040
<v Speaker 1>more complicated than just a simple yes or no. For

0:15:48.120 --> 0:15:53.320
<v Speaker 1>one thing, how much solar exposure is the area getting. Obviously,

0:15:53.360 --> 0:15:55.160
<v Speaker 1>if you're not getting a lot, then that's not going

0:15:55.240 --> 0:15:58.240
<v Speaker 1>to be a good choice for solar towers or a

0:15:58.240 --> 0:16:00.720
<v Speaker 1>good place to put a solar tower. I should say

0:16:01.400 --> 0:16:05.520
<v Speaker 1>also not just where, and and you know what time

0:16:05.560 --> 0:16:08.040
<v Speaker 1>of year do you get solar exposure? Those would be

0:16:08.040 --> 0:16:12.000
<v Speaker 1>two big things. But how much does electricity cost in

0:16:12.040 --> 0:16:14.440
<v Speaker 1>that region already? And the reason why you have to

0:16:14.440 --> 0:16:17.600
<v Speaker 1>ask that question is if you were to provide electricity

0:16:17.640 --> 0:16:22.600
<v Speaker 1>through the solar reserve system, would it make financial sense

0:16:22.680 --> 0:16:25.600
<v Speaker 1>to make that switch? If coal is incredibly cheap in

0:16:25.640 --> 0:16:29.560
<v Speaker 1>the area, then financially it might make more sense to

0:16:29.560 --> 0:16:32.320
<v Speaker 1>stick with coal, even though we all know there are

0:16:32.400 --> 0:16:35.560
<v Speaker 1>big environmental drawbacks to using coal. You create a lot

0:16:35.600 --> 0:16:39.080
<v Speaker 1>of fossil fuels, you have a big carbon footprint that way,

0:16:39.080 --> 0:16:45.560
<v Speaker 1>But it's hard to argue with the dollar cost of energy.

0:16:45.720 --> 0:16:50.560
<v Speaker 1>If that dollar cost is higher with solar reserve, that's

0:16:50.560 --> 0:16:53.360
<v Speaker 1>a tough sell because not everyone is willing to spend

0:16:53.480 --> 0:16:58.600
<v Speaker 1>more money to keep their homes, uh, you know, supplied

0:16:58.600 --> 0:17:02.240
<v Speaker 1>with electricity just so that they have a lower carbon

0:17:02.280 --> 0:17:06.760
<v Speaker 1>footprint with the electricity generation. It's just the truth of

0:17:06.760 --> 0:17:08.800
<v Speaker 1>the matter, and some people don't have the money to

0:17:08.920 --> 0:17:13.240
<v Speaker 1>afford the luxury. Obviously, now, if solar reserve is able

0:17:13.320 --> 0:17:16.960
<v Speaker 1>to be significantly less expensive than whatever the alternatives are,

0:17:17.480 --> 0:17:21.600
<v Speaker 1>that's a huge win for solar towers. So it's a

0:17:21.600 --> 0:17:25.280
<v Speaker 1>lot of different questions along those lines. Obviously, there are

0:17:25.320 --> 0:17:28.080
<v Speaker 1>other questions to ask, like what is the carbon footprint

0:17:28.080 --> 0:17:31.560
<v Speaker 1>of actually building the solar tower? But I would argue

0:17:31.600 --> 0:17:35.760
<v Speaker 1>that whatever it is, it probably has significantly less than

0:17:35.800 --> 0:17:39.960
<v Speaker 1>the carbon footprint produced over the lifetime of a coal

0:17:40.040 --> 0:17:45.000
<v Speaker 1>plant or at gas plant or oil plant. Um. I

0:17:45.040 --> 0:17:48.400
<v Speaker 1>think that's pretty a pretty fair assumption, but it still

0:17:48.440 --> 0:17:52.920
<v Speaker 1>could be a very large upfront uh carbon footprint creation there.

0:17:53.520 --> 0:17:55.960
<v Speaker 1>So that's kind of the approach that I wanted to

0:17:56.000 --> 0:17:58.520
<v Speaker 1>talk about, this idea of being able to generate electricity

0:17:58.560 --> 0:18:02.040
<v Speaker 1>twenty four hours a day using on power without it

0:18:02.119 --> 0:18:04.879
<v Speaker 1>being a solar panel, and I thought it was a

0:18:04.920 --> 0:18:09.680
<v Speaker 1>really cool approach to that, something that could really get

0:18:09.720 --> 0:18:14.800
<v Speaker 1>around a tricky problem with solar power because I know

0:18:14.880 --> 0:18:17.520
<v Speaker 1>a lot of critics point out, hey, if the sun

0:18:17.600 --> 0:18:21.560
<v Speaker 1>is not shining, then you're not making electricity. Well that's

0:18:21.560 --> 0:18:24.880
<v Speaker 1>true with your traditional solar panels, but not with solar towers.

0:18:24.920 --> 0:18:29.880
<v Speaker 1>Assuming that you don't enter into some cataclysmic event where

0:18:29.880 --> 0:18:33.480
<v Speaker 1>you've got crazy overcast skies for a really long time,

0:18:33.600 --> 0:18:35.400
<v Speaker 1>in which case, if we do have that, we're gonna

0:18:35.400 --> 0:18:38.960
<v Speaker 1>have other problems besides where we get our electricity. Um oh,

0:18:39.080 --> 0:18:40.879
<v Speaker 1>and you might want to know how much electricity can

0:18:40.920 --> 0:18:43.399
<v Speaker 1>one of these facilities generate. It would be good for

0:18:43.440 --> 0:18:46.160
<v Speaker 1>me to tell you that. So Solar Reserves says that

0:18:46.280 --> 0:18:49.439
<v Speaker 1>depending on the plant design, it can generate between fifty

0:18:49.480 --> 0:18:53.119
<v Speaker 1>and two hundred megawatts of electricity, and one megawatt is

0:18:53.240 --> 0:18:57.160
<v Speaker 1>enough power to supply around a thousand homes. So you're

0:18:57.160 --> 0:19:00.720
<v Speaker 1>talking about with one solar tower facility, but between fifty

0:19:00.760 --> 0:19:04.280
<v Speaker 1>thousand and two hundred thousand homes. Obviously, there are a

0:19:04.280 --> 0:19:06.280
<v Speaker 1>lot of cities that are bigger than that, and in

0:19:06.359 --> 0:19:09.359
<v Speaker 1>order to supply the electricity for those cities, you would

0:19:09.400 --> 0:19:14.120
<v Speaker 1>need multiple solar tower facilities to to do that. Uh.

0:19:14.160 --> 0:19:17.439
<v Speaker 1>And again that's another question is where would this be

0:19:17.520 --> 0:19:20.399
<v Speaker 1>most appropriate. Obviously a lot of desert towns that have

0:19:21.240 --> 0:19:25.840
<v Speaker 1>medium to small populations. This would be an amazing approach

0:19:25.880 --> 0:19:29.040
<v Speaker 1>to generating electricity, but it might not work for some

0:19:29.119 --> 0:19:33.960
<v Speaker 1>place like New York City for multiple reasons, the population size,

0:19:34.440 --> 0:19:38.120
<v Speaker 1>the lack of land to dedicate to solar power, Obviously,

0:19:38.119 --> 0:19:40.159
<v Speaker 1>that's another issue is that if you are going to

0:19:40.200 --> 0:19:44.360
<v Speaker 1>dedicate land to a solar tower facility, you're not able

0:19:44.400 --> 0:19:47.800
<v Speaker 1>to use that land for other stuff, at least not easily,

0:19:48.240 --> 0:19:51.719
<v Speaker 1>So that's another consideration. Obviously, you don't want to end

0:19:51.800 --> 0:19:54.240
<v Speaker 1>up going to a place where you're dedicating land that

0:19:54.280 --> 0:19:59.440
<v Speaker 1>could be otherwise used for a more productive purpose, possibly

0:19:59.480 --> 0:20:02.080
<v Speaker 1>not in g related. It might be food related, or

0:20:02.119 --> 0:20:04.960
<v Speaker 1>water or something along those lines. So a lot of

0:20:04.960 --> 0:20:07.159
<v Speaker 1>things to take into consideration. But I think it's a

0:20:07.280 --> 0:20:10.919
<v Speaker 1>very elegant approach to generating electricity in a using a

0:20:10.960 --> 0:20:16.239
<v Speaker 1>renewable resource the Sun's energy, and very low impact to

0:20:16.280 --> 0:20:20.479
<v Speaker 1>the environment. The moulten salts are inert, they're not dangerous. Uh.

0:20:20.840 --> 0:20:23.080
<v Speaker 1>They're obviously dangerous in their temperature. You would not want

0:20:23.119 --> 0:20:26.440
<v Speaker 1>to touch them while they're at a thousand fifty degrees fahrenheit,

0:20:27.280 --> 0:20:32.000
<v Speaker 1>but they're not dangerous to the environment. Uh. And these, again,

0:20:32.119 --> 0:20:35.400
<v Speaker 1>the systems are separate. The water system and the salt

0:20:35.440 --> 0:20:38.480
<v Speaker 1>system are separate from each other. So I think it's

0:20:38.480 --> 0:20:41.360
<v Speaker 1>a really interesting approach. Now I'm curious to hear what

0:20:41.440 --> 0:20:46.159
<v Speaker 1>you guys think about the most promising energy sources for

0:20:46.160 --> 0:20:48.920
<v Speaker 1>the future. Do you really think that solar power is

0:20:48.960 --> 0:20:53.800
<v Speaker 1>going to become a major way to offset our electricity generation.

0:20:53.920 --> 0:20:57.600
<v Speaker 1>I'm pretty sure. I feel fairly confident it's never going

0:20:57.640 --> 0:21:01.960
<v Speaker 1>to be the primary way we generate electricity. I don't

0:21:01.960 --> 0:21:05.520
<v Speaker 1>think it's practical enough to be our primary, but I

0:21:05.600 --> 0:21:09.240
<v Speaker 1>certainly see it as a very strong contender for a

0:21:09.400 --> 0:21:14.560
<v Speaker 1>support system, something that can offset some of our electricity needs.

0:21:15.359 --> 0:21:16.600
<v Speaker 1>But what do you think? Do you think there are

0:21:16.600 --> 0:21:19.719
<v Speaker 1>other ones that are better? Do you think wind power

0:21:19.920 --> 0:21:23.240
<v Speaker 1>is better than solar or maybe, uh, maybe you think

0:21:23.760 --> 0:21:28.600
<v Speaker 1>hydro power is better, Maybe you think geothermal. Maybe you're

0:21:28.640 --> 0:21:32.320
<v Speaker 1>looking for that nuclear fusion approach. If that break If

0:21:32.359 --> 0:21:34.199
<v Speaker 1>there is a breakthrough nuclear fusion, that would be an

0:21:34.359 --> 0:21:38.280
<v Speaker 1>enormous benefit to all of humanity because we would suddenly

0:21:38.760 --> 0:21:42.919
<v Speaker 1>be capable of going into an era of energy surplus,

0:21:43.600 --> 0:21:47.439
<v Speaker 1>which would be phenomenal. And I hope it happens, But

0:21:47.520 --> 0:21:50.040
<v Speaker 1>there are a lot of challenges to get out of

0:21:50.080 --> 0:21:51.879
<v Speaker 1>the way first. And maybe I'll do a full episode

0:21:51.880 --> 0:21:54.400
<v Speaker 1>about nuclear fusion in the in the future and talk

0:21:54.440 --> 0:21:58.800
<v Speaker 1>about why it's such a tricky issue. But guys, I

0:21:58.800 --> 0:22:00.640
<v Speaker 1>want to hear what you think. Where do you think

0:22:00.680 --> 0:22:02.639
<v Speaker 1>the future of our energy comes from let me know,

0:22:02.920 --> 0:22:06.880
<v Speaker 1>send me an email, our addresses, text stuff at how

0:22:06.960 --> 0:22:09.640
<v Speaker 1>stuff works dot com, or drop me a line on

0:22:09.680 --> 0:22:12.080
<v Speaker 1>Facebook or Twitter. At both of those, you can find

0:22:12.080 --> 0:22:15.679
<v Speaker 1>me with the handle text stuff h s W and

0:22:15.720 --> 0:22:22.480
<v Speaker 1>I'll talk to you again really soon. For more on

0:22:22.560 --> 0:22:25.040
<v Speaker 1>this and Bathans of other topics, is a house stuff

0:22:25.080 --> 0:22:35.560
<v Speaker 1>works dot com