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How Desalination Works · Stuff You Should Know

0:00
Speaker 1: Welcome to you Stuff you should know from House Stuff
0:03
Speaker 1: Works dot com. Hey, and welcome to the podcast. I'm
0:12
Speaker 1: Josh Clark. There's Charles W. Chuck Bryant and guest producer. No,
0:16
Speaker 1: so this is stuff you should know, Stuff you should know. Yeah,
0:22
Speaker 1: Neil has been waiting for that one for a month.
0:24
Speaker 1: That's right, Well you got it, know finally. How do
0:27
Speaker 1: you feel? It feels great? Just woke me up? Uh?
0:33
Speaker 1: Are you're doing okay? I'm doing fine, sir. I think
0:37
Speaker 1: we need more air circulation in this place, in our
0:39
Speaker 1: new little Uh. It makes you LOGI makes me logi?
0:43
Speaker 1: What's logi? Josh? Just mimic being tired? Okay, A right,
0:49
Speaker 1: I've never heard that. Is that a real word logi?
0:53
Speaker 1: Or is it some Internet short for something much older
0:57
Speaker 1: than that? Okay, keep hello? And what I don't know something? Uh,
1:04
Speaker 1: it's something g I. That's first of balls you're thinking of? Yeah,
1:08
Speaker 1: I don't know what any of the little internet shorthand is.
1:11
Speaker 1: I always have to look that stuff up when someone
1:13
Speaker 1: leaves a comment. Um, have you heard of first of balls?
1:17
Speaker 1: Instead of first of all? It's now first of bulls?
1:21
Speaker 1: What just by leading us in? It's like first of all,
1:23
Speaker 1: blah blah blah. First of balls, what Yeah, that's just stupid.
1:30
Speaker 1: Now I'm at more of the acronyms like fomo and
1:33
Speaker 1: oh yeah, I have to I never know what those are.
1:36
Speaker 1: We're getting aged. We think first of alls is stupid.
1:40
Speaker 1: We have to look at acronyms. I look up fomo
1:43
Speaker 1: if you're missing out by the way, Oh, is that
1:46
Speaker 1: what that is? Yeah? I had to look up that.
1:49
Speaker 1: When I was watching Broad City. One of them said that,
1:51
Speaker 1: and I was like, what's fomo? I gotta I gotta
1:54
Speaker 1: keep the old internet handy when I watch those young
1:56
Speaker 1: kids shows. That shows pretty funny. Yeah, it's one. It's
1:59
Speaker 1: my favorite comment the out right. Now. I think I'm
2:01
Speaker 1: really really enjoy it. I just posted today, in fact,
2:05
Speaker 1: on our Facebook page, a great to New Yorker article
2:08
Speaker 1: on Abbey and Allana. Nice because you know how that
2:10
Speaker 1: the New Yorker does it, They do it great in depth. Yeah,
2:15
Speaker 1: you know, you feel like I never have to read
2:17
Speaker 1: another article again about the ladies of Broad City. When
2:21
Speaker 1: the New Yorker does it, it stays done. That's I
2:23
Speaker 1: think their masked head, is it. Yeah, the New Yorker,
2:27
Speaker 1: when we do it, it stays done. I've read at
2:30
Speaker 1: New Yorker article from that was still awesome about this
2:35
Speaker 1: band called the Shags. It was a super Orleans article
2:39
Speaker 1: at the Orchid thiefure Um. But it was about this
2:43
Speaker 1: this family band, a girl band called the Shags from
2:48
Speaker 1: the sixties. I've heard of them who, like I, didn't
2:51
Speaker 1: really learn to play their instruments, even though they practice
2:53
Speaker 1: all the time. Yep, you're going to be a band.
2:58
Speaker 1: He tried to take him to the top as much
3:00
Speaker 1: as he could, even right. Yeah, yeah, I remember reading it.
3:04
Speaker 1: That might have been the same article, but are super interesting.
3:06
Speaker 1: Our friend Van nostri And sent us the record. Oh okay,
3:10
Speaker 1: maybe that's what got me looking into it. The only
3:13
Speaker 1: problem is that he burned it on CD and like, like,
3:16
Speaker 1: our computers don't have CD players mine? Does it home? Good? Yeah?
3:21
Speaker 1: Well I need you to put it on the cloud.
3:23
Speaker 1: You just come over listen to the Shags of the
3:25
Speaker 1: Shags party. Wait, we're talking about illegal activities. We need
3:29
Speaker 1: to buy the Shag album. I don't think it's still
3:31
Speaker 1: in print. Okay, Chuck, Yes, are you familiar with seawater? Yes? Uh,
3:38
Speaker 1: you know there's tons of it out there in the world.
3:41
Speaker 1: That's right. As a matter of fact, chuckers. Seven point
3:45
Speaker 1: five percent of all the water and earth, and that's
3:48
Speaker 1: seventy of the Earth's surface area is water, right, Yeah,
3:53
Speaker 1: seven point five percent of that is saltwater sea water,
3:58
Speaker 1: which is great. It's good for sailing on, its good
4:00
Speaker 1: for swimming in, it's good for catching um porpoises in
4:05
Speaker 1: doing all sorts of cool stuff, right porpoise fishing expedition. Right. Um.
4:10
Speaker 1: The problem is it is terrible, horrible, unbearable for drinking.
4:18
Speaker 1: The reason why is because when you drink salt water,
4:21
Speaker 1: it messes with your body's homeostasis. Does this because salt
4:27
Speaker 1: is an electro light, just like they talk about in Um,
4:33
Speaker 1: what's that Mike Judge movie that I love that you
4:35
Speaker 1: don't like? Oh idiocricy idiocracy. Yeah, remember they water the
4:41
Speaker 1: crops with gatoring because it has electro lights. I do
4:45
Speaker 1: not like it. I love that movie. It's a medium
4:47
Speaker 1: for me. Okay. Um, When you have too many electrolytes
4:52
Speaker 1: or salts, for example, in your body, your body says, hey, cells,
4:58
Speaker 1: you've got a bunch of water, We've got too much
5:00
Speaker 1: salt outside of you. We need you to release some
5:03
Speaker 1: of your water to return the body to homeostasis. Well,
5:07
Speaker 1: if you have too much salt, yourselves purge themselves with
5:10
Speaker 1: too much water in order to excrete the salt out
5:14
Speaker 1: of your body through urine. Right. Um. And once you
5:18
Speaker 1: do that, you dehydrate your kiddie's malfunction, your brain starts
5:21
Speaker 1: to go downhill, you get brain damage, and you ultimately
5:24
Speaker 1: die a terrible, horrible death from electrolyton balance. Yeah, and
5:27
Speaker 1: that's why when, um, if you were ever lost at sea,
5:30
Speaker 1: let's hope that never happens to anyone. But um, they
5:33
Speaker 1: you do not drink the salt water. It would be
5:36
Speaker 1: very tempting because it's right there. Um, But they're not
5:40
Speaker 1: kidding when they say water water everywhere, and not a
5:42
Speaker 1: drop to drink. Yeah, I mean you will. You will
5:44
Speaker 1: die a quicker death if you start drinking that salt water.
5:47
Speaker 1: In fact, this has been like a problem for a
5:50
Speaker 1: very long time. Humans have lived in coastal areas for
5:54
Speaker 1: a long, long long time, even before civilization, long long
5:58
Speaker 1: long time. Yeah, so as far because I believe the
6:00
Speaker 1: Greeks in the second century BC wrote down ways of
6:05
Speaker 1: getting fresh water from saltwater because it's still water. Sure,
6:09
Speaker 1: you just have to figure out how to get the
6:11
Speaker 1: salt out of the water. And one of the best ways,
6:14
Speaker 1: one of the earliest ways, and one of the ways.
6:16
Speaker 1: It's still in use, although in much more high tech
6:19
Speaker 1: use is called solar still. Yeah, I guess a little
6:23
Speaker 1: bit more on the history Aristotle, Uh three BC, it
6:28
Speaker 1: was like, hey, we should desalinate water. So that's the
6:31
Speaker 1: zero two hundred, that'd be the fourth century BC. Okay,
6:37
Speaker 1: I was wrong. Uh. Plenty the elder, which we by
6:40
Speaker 1: the way, is there a younger? We just got some beer,
6:42
Speaker 1: some plenty the elder. Yeah, thank you Dan, It was Dan, Dan, dude,
6:49
Speaker 1: very much appreciated. I just can't get that stuff here. No,
6:52
Speaker 1: it's an extraordinarily rare beer. Uh dancing of some plenty
6:56
Speaker 1: the elder, So thanks for that. But plenty the elder
6:58
Speaker 1: in Rome Uh also described seawater distillation, and in seventy
7:04
Speaker 1: a d Alexander of Afrodysseus also did so. About a
7:09
Speaker 1: hundred and thirty years later, and then there was a
7:12
Speaker 1: French explorer named gen de Lrie. Who um did you
7:16
Speaker 1: like that? Who Um? In Fifi talked about desalination. James
7:22
Speaker 1: Cook as well, so it's not a new thing. For
7:25
Speaker 1: many years, humans have been able to look around and say,
7:29
Speaker 1: you want water, There's plenty of it. Let's just figure
7:32
Speaker 1: out a way to to make it not salty. Water
7:35
Speaker 1: water everywhere, and let's all have a drink. Yeah, which
7:39
Speaker 1: got me um thinking sort of later in the research,
7:42
Speaker 1: like why is the ocean salty to begin with? And
7:45
Speaker 1: I didn't really know until I looked it up. That
7:47
Speaker 1: was a good question. Yeah. It turns out that salt
7:51
Speaker 1: from the ocean comes from rocks here on Earth. It's
7:56
Speaker 1: not just out there in the ocean it Um. What
7:58
Speaker 1: happens is it rains and then uh, it falls on
8:02
Speaker 1: the land and it contains carbon dioxide from the air,
8:06
Speaker 1: and that makes the rain slightly acidic. So when it
8:08
Speaker 1: hits the rocks, it's gonna break down that rock. Some
8:11
Speaker 1: creating ions, which we've talked about chemical particles that are charged, Yeah,
8:17
Speaker 1: because they're missing an electron, that's right. Uh. And these
8:21
Speaker 1: ions are basically just carried into streams, which eventually into
8:25
Speaker 1: rivers and eventually into oceans, and along the way, a
8:28
Speaker 1: lot of them are used up by organisms. Um, but
8:32
Speaker 1: the ones that are not used up are left over.
8:35
Speaker 1: And of all these ions are sodium and chloride. So boom,
8:40
Speaker 1: there you have it. Put those two together, you've got salt. Yep,
8:44
Speaker 1: and all that stuff flows in the ocean. And that's
8:45
Speaker 1: why you have got a couple of stats. The three
8:49
Speaker 1: point five percent of the weight of seawater comes from
8:51
Speaker 1: dissolved salts. And they say, some say that if you
8:55
Speaker 1: took all the salt from the ocean and spread it
8:59
Speaker 1: evenly over the Earth's land, just the land, it would
9:03
Speaker 1: be about a forty stories high five feet thick. Wow,
9:07
Speaker 1: there's a lot of salt to get rid of you
9:10
Speaker 1: and it's all from broken down rocks. Huh. Yeah. And
9:13
Speaker 1: why is desalination a big deal? Because? Uh, clean potable
9:19
Speaker 1: drinking water is a problem in a lot of parts
9:21
Speaker 1: of the world. Dude, it is getting to be a
9:23
Speaker 1: problem faster and faster. Yeah. Like some people say that
9:27
Speaker 1: the future wars will be fought over water, which is
9:30
Speaker 1: really scary to think about, you know. Um, and for
9:33
Speaker 1: drought to like, uh, it's not just you know, I'm
9:36
Speaker 1: in a developing country and we don't have access to
9:39
Speaker 1: clean drinking water, big problem, But places like California suffer
9:42
Speaker 1: a drought, Like maybe we should think about building desalination plants, right,
9:46
Speaker 1: and they have as a result. Yeah, which we'll get to.
9:49
Speaker 1: So so first of all, we should say happy World
9:51
Speaker 1: Water Day to everybody. It's March two is World Water Day.
9:56
Speaker 1: So just think about that while you're you know it's
10:00
Speaker 1: March um. And yes, so there's a there's a great
10:05
Speaker 1: need for water. That's the whole reason for World Water
10:08
Speaker 1: Day is to point that out. Supposedly right now, seven
10:12
Speaker 1: million people, um, black access to water. They don't have.
10:18
Speaker 1: There's a water scarcity clean drinking water, yes, um. And
10:23
Speaker 1: they think that that's gonna rise to one point eight
10:26
Speaker 1: billion by in ten years. It's gonna add another one
10:30
Speaker 1: point one billion people to those who face water shortages. Yeah.
10:35
Speaker 1: We talked about that a little bit in our Life
10:37
Speaker 1: Straw podcasts from quite a few years ago. But the
10:40
Speaker 1: life straw is a um it's about to say single use,
10:44
Speaker 1: not single use, but single serving, single well, not single serving.
10:49
Speaker 1: It's uh what do you call it? If like it's
10:51
Speaker 1: just for one person or a family, uh, single person? Personal? Yeah, heirloom.
10:58
Speaker 1: It's a personal uh device that you can use to
11:02
Speaker 1: literally drink water like out of a river through this straw.
11:06
Speaker 1: You just put it in the river. It's got filters
11:08
Speaker 1: in it, so it filters out I don't it doesn't
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Speaker 1: filter out salid and it has to be used for
11:12
Speaker 1: fresh water, but it filters out like bacteria, things that
11:16
Speaker 1: you know, disease causing stuff. Um. So, yeah, we did
11:20
Speaker 1: talk about water scarce today. I think we've talked about
11:22
Speaker 1: it in another one too, like why can't we manufacture
11:24
Speaker 1: water and things like that. It's part of our water
11:26
Speaker 1: sweet it is, and it's ongoing because the problem is
11:30
Speaker 1: not getting better, it's getting worse. One of one of
11:33
Speaker 1: the responses to water shortages around the world is what's
11:37
Speaker 1: called virtual water exporting, which is where you and I
11:42
Speaker 1: have a bunch of fresh water and we use it
11:45
Speaker 1: to grow grain, and then we send that grain to
11:48
Speaker 1: a place that doesn't have much water, so they get
11:51
Speaker 1: to use their water for drinking. They don't have to
11:53
Speaker 1: use it for grain. That makes so and there's a
11:56
Speaker 1: lot of different things that we use water for that
11:58
Speaker 1: can be exported. It's hard to explore water, but you
12:01
Speaker 1: can use it for stuff and save other people from
12:04
Speaker 1: having to use it. Right. Um, because we use a
12:07
Speaker 1: lot of water. We do use a lot of water,
12:09
Speaker 1: Americans especially, but you hear stats like, oh, this desalination
12:13
Speaker 1: plant can pump out like fifteen billion gallons of fresh water.
12:17
Speaker 1: You think, man, fifteen billion gallons is so much. It's
12:20
Speaker 1: not very much at all. No, it's not a scheme.
12:22
Speaker 1: I think fifteen billion goallons of water is two thirds
12:26
Speaker 1: of a percent, two thirds of one percent of the
12:30
Speaker 1: amount of water used by humans every day. Yeah, and um,
12:36
Speaker 1: I think all of the desalination plants online, there's seventeen
12:39
Speaker 1: thousand of them. Yeah, and that accounts. I think that's
12:44
Speaker 1: all of them, from the from the very small ones
12:47
Speaker 1: to the ones that are also used in like uh
12:51
Speaker 1: as part of the fracking process. So it's not necessarily
12:55
Speaker 1: all of those are to deliver water to humans. But yeah,
12:58
Speaker 1: there are that many. So the seventeen thousand desalination plants
13:03
Speaker 1: online in the world, and they think that could double
13:06
Speaker 1: by um, which is pretty good. That's those seventeen thousand
13:11
Speaker 1: of producing twenty one billion gallons a day. I remember,
13:14
Speaker 1: fifteen billion is two thirds of one percent of all
13:17
Speaker 1: of the fresh water used every day around the world.
13:20
Speaker 1: So it's still sorry for the pun, but a drop
13:23
Speaker 1: in the bucket. Yeah, but things are changing fast. They
13:28
Speaker 1: are this new one in California, which we're going to
13:31
Speaker 1: talk about later. UM is the largest in the Western Hemisphere.
13:35
Speaker 1: Will produce fifty million gallons per day on its own.
13:38
Speaker 1: It's pretty substantial, pretty substantial. UM. So we'll talk about
13:41
Speaker 1: the technology used in this. It's actually kind of old.
13:45
Speaker 1: It needs a little updating, right for this, So, Chuck,
14:11
Speaker 1: there's basically two ways that humans desalinate sea water. Yeah
14:18
Speaker 1: and UM. They've both been around for many, many decades.
14:22
Speaker 1: They're in theory. They're pretty good at removing sea salt
14:28
Speaker 1: from seawater to create fresh water. But there's over the
14:32
Speaker 1: course of these decades we've found this could be improved,
14:36
Speaker 1: This could be improved. That can be improved, and we'll
14:38
Speaker 1: talk about that later. But this technology, it's been around
14:41
Speaker 1: for a little while, is what I'm trying to say.
14:44
Speaker 1: UM and the two different The main competitors are UM,
14:48
Speaker 1: multi stage flash UH desalination. Yeah. Sometimes I've talked like
14:56
Speaker 1: Barack Obama, Well that's a good thing. I'm not getting political,
15:01
Speaker 1: Dge mean, he's known as a great orator, was Chuck
15:04
Speaker 1: was uh? And and the other one is reverse osmosis.
15:09
Speaker 1: Do you remember like that poster in in elementary school
15:13
Speaker 1: it was like Garfield laying down on a pile of
15:15
Speaker 1: books taking a nap, and it said, I'm learning through osmosis.
15:18
Speaker 1: I think I do remember that. I was the Garfield
15:21
Speaker 1: fan think that every time I see the word osmosis. Yeah,
15:24
Speaker 1: I didn't get the joke when I was a kid,
15:26
Speaker 1: and now that I do get, it's not that funny,
15:28
Speaker 1: but I'm reminded of it every time. Yeah, he didn't
15:32
Speaker 1: understand why it Lasagna right. Yeah, it's kind of weird
15:37
Speaker 1: to think about now. And the so the reverse osmosis
15:40
Speaker 1: one is the state of the art. That's the one
15:43
Speaker 1: that's used most widely. Yes, and uh, I think that
15:47
Speaker 1: term was coined in the nineteen fifties by the U. S. Military.
15:52
Speaker 1: I think we're the first ones to start using that process. Yeah,
15:55
Speaker 1: World War two makes sense. It was an Eisenhoward creation probably. Yeah, Like,
15:59
Speaker 1: we're out on this eye in the Pacific. Our soldiers
16:01
Speaker 1: need some stuff, so let's start a process to um
16:04
Speaker 1: buy stuff, I mean water. We'll start a process where
16:07
Speaker 1: we can take the salt out of the water all
16:08
Speaker 1: around us. And so they did reverse osmosis. Yeah, and
16:12
Speaker 1: and again, I mean we talked about solar stills right, Yeah,
16:16
Speaker 1: I don't think we described like. You can do this
16:18
Speaker 1: experiment yourself and your at your house. Well. And also,
16:21
Speaker 1: if you're ever caught without without water, you're stranded at sea. Yea,
16:27
Speaker 1: all you need is a bowl and a glass rap
16:32
Speaker 1: and you're fine. Yeah, I mean you can use other things,
16:35
Speaker 1: like if you were Tom Hanks and castaway, you could
16:39
Speaker 1: just try and use the things around you to create
16:41
Speaker 1: the same effect. But yes, go ahead and describe it. Well,
16:44
Speaker 1: you take you take some seawater, you put it in
16:47
Speaker 1: a bowl. You put an empty glass in the middle
16:49
Speaker 1: of that water. Um, I guess you want to make
16:53
Speaker 1: sure it doesn't float. Other than that, you're fine. Put
16:55
Speaker 1: some stine wrap over it. Poke a hole in the
16:58
Speaker 1: middle of the surrand wrap so that it's over the
17:00
Speaker 1: center of the empty glass, and just set it out
17:03
Speaker 1: in the sun. Yeah, because the sun will cause the
17:07
Speaker 1: water to evaporate, which means it will go up to
17:09
Speaker 1: the underside of the suran wrap, cling to it and
17:14
Speaker 1: condensate into the glass. Oh yeah, into the glass, right,
17:20
Speaker 1: And what goes into the glass will be freshwater. The
17:23
Speaker 1: salt will be left behind because the evaporation will have
17:26
Speaker 1: separated the two. Yeah, and we're basically described describing you know, rain, right,
17:31
Speaker 1: the rain cycle, but in a glass of suran wrap exactly.
17:34
Speaker 1: And by seran wrap we mean like cellophane wrap. Um.
17:40
Speaker 1: But that's a solar still, that's pretty basic. You can
17:43
Speaker 1: do it on a rowboat again, if you have a
17:44
Speaker 1: glass of bowling suran wrap. Um. Reverse osmosis is something different,
17:49
Speaker 1: that's right. It's actually the opposite of natural. Quite literally, yes,
17:54
Speaker 1: because osmoses is natural. Reverse osmoses ain't natural. It ain't natural.
17:58
Speaker 1: That is when you put salt water on one side
18:02
Speaker 1: of the membrane, semiprobreable membrane and he use pressure to
18:06
Speaker 1: the tune of I think this one in California is
18:08
Speaker 1: like they said, six times as powerful as a fire hose.
18:13
Speaker 1: Whoa so serious pressure to um to move the water
18:17
Speaker 1: molecules through that membrane basically, and it's it's like a
18:20
Speaker 1: big filter filters out the salt. Yeah, it's it's calling
18:24
Speaker 1: it anything else, but a filter is kind of fancy. Yeah,
18:27
Speaker 1: because I think they said the pores on these membranes
18:29
Speaker 1: are like smaller than a human hair. So it's not
18:33
Speaker 1: like your average filtering, you know what I mean. No,
18:35
Speaker 1: it's not The point is what you're doing is you're
18:38
Speaker 1: you're pushing water through membrane that the water can make
18:41
Speaker 1: it through, but the salute, the salt inside of it can't,
18:45
Speaker 1: so the salt is left behind, right and um in
18:48
Speaker 1: a reverse osmosis system, and they call it reverse osmosis
18:51
Speaker 1: because under normal osmosis, what you have is something with
18:56
Speaker 1: a low concentration of a slute, So fresh water water
19:00
Speaker 1: on one side of a membrane and saltwater on the
19:03
Speaker 1: other side of the membrane. That water is going to
19:08
Speaker 1: the freshwater is going to move from the area of
19:12
Speaker 1: low concentration, so the freshwater is going to move to
19:15
Speaker 1: an area of higher concentration the saltwater in order to
19:18
Speaker 1: achieve one of our favorite things, homeostasis, it wants to
19:23
Speaker 1: achieve a balance so that the stuff on either side
19:26
Speaker 1: of the membrane will be equally salty. Right that that
19:30
Speaker 1: makes sense, Okay? Reverse ASBOs is the opposite. So if
19:34
Speaker 1: water naturally wants to go from low concentration too high,
19:38
Speaker 1: with reverse osmosis, you're going from high concentration to low.
19:43
Speaker 1: And that's just again another way of putting it, of
19:46
Speaker 1: saying you're filtering the salt from the water by pushing
19:49
Speaker 1: the water through a membrane with a lot of pressure
19:52
Speaker 1: via a lot of pumps. Yeah, and you're running it
19:54
Speaker 1: through a lot more than just one membrane. Oh sure, yeah, yeah, great.
20:00
Speaker 1: So that's reverse osmosis number one. Uh and not number
20:05
Speaker 1: one in ranking, just it's number one in my book.
20:08
Speaker 1: It see, I'm a multi stage flash guy, are you sure?
20:11
Speaker 1: Why not? Uh? That uses heat. If you've heard of flashing,
20:15
Speaker 1: like flash buying or something, basically means to do something
20:18
Speaker 1: cooking wise very quickly. Um. So flashing in this case
20:22
Speaker 1: is bringing water to a boil really quickly, and multi
20:26
Speaker 1: stage means you're gonna do it in different stages multiple times.
20:29
Speaker 1: So the name makes sense. Yeah. So basically what you're
20:31
Speaker 1: doing is you're gonna boil this water super fast many times.
20:36
Speaker 1: And each time this happens, water vapor is going to form,
20:40
Speaker 1: and uh, you're gonna have fresh water there and then
20:43
Speaker 1: the salty brine is left over to be disposed of.
20:47
Speaker 1: It's like making a solar still, like a flash boiled
20:50
Speaker 1: solar still over and over again. That's right. So yeah,
20:53
Speaker 1: multi flash, multi stage flash is like um, a super
20:58
Speaker 1: hot solar still over and over again, and each time
21:01
Speaker 1: you collect that evaporated fresh water behind. There's some real
21:07
Speaker 1: issues with both of these right, as simple as they are.
21:11
Speaker 1: Um And one of the chief ones is that if
21:13
Speaker 1: you take a bunch of saltwater, right and you either
21:17
Speaker 1: filter the freshwater out of it or you boil the
21:22
Speaker 1: fresh water out of it, there's still something left, and
21:25
Speaker 1: that is salt, and you're probably not gonna get all
21:28
Speaker 1: the water. So what you have is called brine. And
21:31
Speaker 1: if you compare brine to seawater, brian is even saltier
21:35
Speaker 1: than seawater. The reason why is there's not more salt
21:38
Speaker 1: than there's in seawater. There's just less water. So it's
21:42
Speaker 1: like an ultra concentrated form of seawater. Well, you're not
21:46
Speaker 1: gonna do anything with this except try to put it
21:48
Speaker 1: back in the ocean. Once you do that, you have
21:51
Speaker 1: a big, big problem because you kill a lot of
21:54
Speaker 1: the sea life. Yeah. It basically it's heavier, so it
21:57
Speaker 1: settles down on the bottom. And um So the things
22:01
Speaker 1: that they're trying now to combat that is uh one, uh,
22:06
Speaker 1: diluting it with a bunch of other water. Yeah, I
22:10
Speaker 1: think of five to one ratio is what they are
22:12
Speaker 1: suggesting at this point. And they're not saying like, well,
22:15
Speaker 1: we'll just use some of the fresh water we just
22:17
Speaker 1: distilled out. That wouldn't make any sense. They're using things
22:19
Speaker 1: like UM industrial or agricultural waste water that they were
22:24
Speaker 1: just gonna pump into the ocean anyway, exactly, So mix
22:28
Speaker 1: it with that brine diluted out and it's not going
22:30
Speaker 1: to be as bad for the environment. Uh. They're also
22:33
Speaker 1: doing it gradually now, much much slower, which also helps. Uh.
22:37
Speaker 1: They're strategically placing it in the ocean in places where
22:42
Speaker 1: it is more UM apt to disperse very quickly. It's
22:47
Speaker 1: a very strategic placement. I think in Australia they try
22:51
Speaker 1: to do uh, they try to re release it to
22:54
Speaker 1: the tune of UM a hundred and sixty two fifty
22:57
Speaker 1: ft away, you won't tell any difference in the are
23:00
Speaker 1: uh salt concentrations. And then the last thing that they're
23:04
Speaker 1: trying to enforce whenever we build these new plants is
23:07
Speaker 1: UM to bury these pipes and actually do it under
23:11
Speaker 1: the sea floor. Uh. Out of yeah, well, I mean
23:15
Speaker 1: out of side. In other words, is not being released
23:17
Speaker 1: directly into the water. It's being released into the sand
23:20
Speaker 1: under the water, and then I think the sand actually
23:23
Speaker 1: acts as it filter as it disperses. But that's a
23:26
Speaker 1: lot more expense as well to bury these pipes, um,
23:30
Speaker 1: so chuck. Dealing with Brian is just one challenge that
23:33
Speaker 1: desalination engineers have to deal with the plenty of other
23:37
Speaker 1: ones that popped up over time and come up with
23:40
Speaker 1: some pretty cool solutions or ideas for solving some of
23:43
Speaker 1: these problems. We're gonna get into that right after this,
24:08
Speaker 1: so chuck. Um. When you put seawater through reverse osmosis
24:13
Speaker 1: or multi stage flash, you end up with Brian and
24:16
Speaker 1: you have to figure out what to do with that Brian.
24:18
Speaker 1: There's some other problems too with desalination. For one, it's expensive. Um.
24:25
Speaker 1: Apparently they measure water on the scale of things like
24:29
Speaker 1: desalination plants and something called um what foot acre, and
24:35
Speaker 1: a foot acre is like three thousand gallons, and a
24:38
Speaker 1: foot acre is about the amount of water at a
24:43
Speaker 1: two American households of five people using a year UM
24:49
Speaker 1: too to deliver desalinated water. At least for the major
24:53
Speaker 1: plant that they're building at Carlsbad, California, UM, it's gonna
24:56
Speaker 1: be about two thousand dollars per foot acre. Yeah, and
25:00
Speaker 1: we've seen ranges and other articles from other plants um
25:03
Speaker 1: averaging eight hundred to fourteen hundred. This one's a little
25:06
Speaker 1: bit on the high side. But what they're doing is
25:08
Speaker 1: selling it back to the UH city at a rate
25:12
Speaker 1: of two thousand, fourteen to two thousand, two hundred and
25:15
Speaker 1: fifty seven dollars per foot acre, depending on how much
25:20
Speaker 1: they're buying at a time. So basically that's how they
25:23
Speaker 1: paid for this thing in California. Because they're super expensive
25:26
Speaker 1: to build these plants. They got a thirty year contract
25:29
Speaker 1: agreeing to buy at least forty eight thousand acres acre
25:32
Speaker 1: feet per year, so bonds on that and now they
25:36
Speaker 1: can open their plant. But the problem is, and the
25:39
Speaker 1: reason a lot of people are upset about this is
25:41
Speaker 1: they're like, it's gonna start costing more and more, and like,
25:44
Speaker 1: what happens then, I don't know, I guess people pay
25:48
Speaker 1: more for water. Well, people are definitely gonna be paying
25:50
Speaker 1: more for water. That's been a really criticism for a
25:53
Speaker 1: very long time of water in America is that it's
25:56
Speaker 1: um artificially cheap. It's should be way more expensive than
26:02
Speaker 1: it is because there you know, there's plenty of places
26:05
Speaker 1: that have lots of water, but there's also plenty of
26:08
Speaker 1: places that are facing drought. UM and the fact that
26:13
Speaker 1: it's so cheap, people tend to abuse it, don't conserve
26:18
Speaker 1: it as much in places where it's very cheap and inexpensive.
26:22
Speaker 1: So just by increasing the price, there's the school of
26:25
Speaker 1: thought that UM conservation will kick in just because economics
26:31
Speaker 1: kicks in a little more. Yeah, there's some price comparisons here. UM.
26:35
Speaker 1: With this new one in California, the two thousand a
26:38
Speaker 1: foot acre or an acre foot I think we had
26:41
Speaker 1: that backwards is double that of we had acre. UM.
26:46
Speaker 1: It's double that of water obtained if you built a
26:48
Speaker 1: new reservoir to recycle waste water, and it is four
26:52
Speaker 1: times as much as obtaining what they call new water
26:55
Speaker 1: from conservation methods, so water efficient toilets rebates UM paying
27:00
Speaker 1: for farmers to install like drip irrigation. UH, and that's
27:04
Speaker 1: conservation four times UM four times is expensive. It's four
27:11
Speaker 1: four times more expensive than that than the conservation efforts
27:14
Speaker 1: they want to try and push through. One of the
27:15
Speaker 1: reasons it's so expensive is because, especially with reverse osmosis.
27:19
Speaker 1: You said that they were using pressure that that exceeded
27:22
Speaker 1: fire hose pressures right six times. Yeah, Okay, that takes
27:26
Speaker 1: a lot of energy because you start out with intake pipes,
27:30
Speaker 1: which again present their own problems because they suck in
27:33
Speaker 1: lots of sea life. So there's a there's an immedia
27:36
Speaker 1: in um deleterious effect on the sea life by sucking
27:41
Speaker 1: in seawater. Right. Um, So you're sucking in the seawater
27:45
Speaker 1: under high pressure. You're pumping it through sand and charcoal
27:49
Speaker 1: pre treatment. You're pumping it through these membranes, series of
27:53
Speaker 1: you know, usually more than a thousand membranes over a
27:56
Speaker 1: very long distance uh into this treatment plant where it's
28:01
Speaker 1: further treated. All this requires a tremendous amount of energy,
28:05
Speaker 1: right and when you are when you're desalinating seawater, in particular,
28:12
Speaker 1: films back tend to build up on these membranes, which
28:16
Speaker 1: means you're pumps have to work harder, which means more
28:18
Speaker 1: energy is required to pump that water through, which means
28:23
Speaker 1: the costs rise, the environmental impact prices because it's getting
28:27
Speaker 1: energy probably from a coal fire power plant. So you
28:30
Speaker 1: have this new huge desalination plant that's that wasn't there
28:34
Speaker 1: before that's increasing your carbon dioxide emissions. So there's a
28:39
Speaker 1: there's a cost to there's an economic cost. There's also
28:42
Speaker 1: an environmental cost with reverse osmosives plants as they exist
28:46
Speaker 1: right now. Yeah, I've got a stat on the energy
28:48
Speaker 1: required this one in Carl's Bad, California, which is just
28:51
Speaker 1: north of San Diego. It uses thirty eight megawatts of
28:54
Speaker 1: energy per day and that is enough to power homes
28:59
Speaker 1: a day a day that wasn't there before. Yeah, it
29:03
Speaker 1: hasn't gone online yet. When it doesn't two sixteen, it'll
29:06
Speaker 1: be like adding how many five hundred homes worth of
29:10
Speaker 1: energy per day? Yeah, and that's um. I mean, it's
29:16
Speaker 1: great to try and provide because California is doing it
29:18
Speaker 1: specifically for their drought issues. But as we said, even
29:22
Speaker 1: at fifty million gallons a day, it's just a fraction
29:25
Speaker 1: of the problem. And people are there's a lot of
29:28
Speaker 1: people critics saying we don't need to be putting our
29:31
Speaker 1: money in these things. They have examples of m ones
29:35
Speaker 1: that were built. There was one in Santa Barbara that
29:37
Speaker 1: was built in that cost thirty four million to build
29:42
Speaker 1: and after they started it started raining again. Basically they
29:47
Speaker 1: shut it down Australia had spent ten billion on six
29:53
Speaker 1: of these because of their drought in the nineties and
29:55
Speaker 1: two thousand's and four of those are shut down now
29:58
Speaker 1: because it started rain again. And basically they're like, it's
30:02
Speaker 1: not it's costing way too much money to make this
30:04
Speaker 1: water now, we don't need it. Right, Well, it's the
30:06
Speaker 1: same thing as like solar power wind power. When oil
30:09
Speaker 1: gets really expensive, then the investment in that seems smarter
30:14
Speaker 1: because the comparatively speaking, the output of solar power windpower
30:19
Speaker 1: isn't as expensive as that expensive oil, right And when
30:24
Speaker 1: the price of oil drops that that solar power output
30:28
Speaker 1: seems really really expensive comparison, and so investment goes away
30:32
Speaker 1: from it. But what you don't want to have happened,
30:34
Speaker 1: and what they're worried about in California is they're going
30:36
Speaker 1: to build several of these at the cost of like
30:38
Speaker 1: a billion apiece, and they get a lot of rain
30:41
Speaker 1: in five years and then all of a sudden these
30:43
Speaker 1: things are just sitting there. Yeah, So I get the impression.
30:45
Speaker 1: I think it actually says in this San Jose Mercury
30:48
Speaker 1: article you sent um that this Carl's Bad desalination plant
30:53
Speaker 1: outside of San Diego is going to basically be the
30:56
Speaker 1: litmus test for the rest of the state. Yeah, it's
30:58
Speaker 1: a really big deal. So, like either California will say, yes,
31:03
Speaker 1: desalination works and let's start investing in this, or they're
31:07
Speaker 1: gonna say, no, this doesn't work. It has too much
31:09
Speaker 1: of an environmental cost, the water is too expensive. It
31:12
Speaker 1: just isn't what we need to do. We have to
31:14
Speaker 1: figure out some other stuff. Uh, And it's all coming
31:17
Speaker 1: down to this one plant in two thousand and sixteen
31:21
Speaker 1: pretty much. But there's been other success stories throughout the world,
31:25
Speaker 1: like UM has a lot of them. Yeah, Saudi Arabia
31:29
Speaker 1: as a leader in desalination, so too is Israel. UM
31:32
Speaker 1: Australia knows what they're doing. Aruba had at the time
31:36
Speaker 1: it opened the largest um productive desalination plant in the world.
31:41
Speaker 1: So there's a lot of desalination going on. So even
31:44
Speaker 1: if California decides to abandon it, there still needs to
31:47
Speaker 1: be an investment in making these things more energy efficient
31:50
Speaker 1: or environmentally friendly or coming up with new kinds of
31:54
Speaker 1: desalination technology altogether. But whether or not California goes forward
32:01
Speaker 1: with it, that's right at all. Hinges on the Poseidon
32:05
Speaker 1: I think it's what they're calling it, what the plant
32:09
Speaker 1: right for California. But I'm saying, even if that doesn't happen,
32:12
Speaker 1: other plants around the world demand that they're there. We
32:15
Speaker 1: need to make this better. Yeah, absolutely, Yeah, because people
32:18
Speaker 1: need water, so let's figure out a way to get
32:21
Speaker 1: it cheaply and with small environmental impact. Okay, that's right,
32:27
Speaker 1: wasn't there. I think a lot of efforts are being
32:29
Speaker 1: made to too, um invest in ones like it's sort
32:34
Speaker 1: of like the LifeStraw, but not like a gravity fed,
32:38
Speaker 1: family sized desalinator, umstead of these really expensive ones a
32:45
Speaker 1: huge desalination plant, or do you need like a bunch
32:48
Speaker 1: of smaller portable desalination units? Yeah, like a unit that
32:52
Speaker 1: will take care of a village, let's say, in a
32:54
Speaker 1: developing country. Why not. It's pretty interesting, it is for
32:59
Speaker 1: some and water has always struck me. It's very interesting.
33:02
Speaker 1: Every time we do an episode like this, I'm like, man,
33:05
Speaker 1: this stuff gets me. It's a commodity that is becoming
33:09
Speaker 1: more scarce, which is scary to think about because it's
33:11
Speaker 1: such a basic thing that every human needs. Yeah, it's
33:16
Speaker 1: not like well, I mean, things would go bad if
33:19
Speaker 1: we ran out of oil too, but it's not like water. Yeah,
33:22
Speaker 1: I mean like society would collapse and civilization with not
33:27
Speaker 1: everyone's gonna die directly. Yeah, from a lack of oil.
33:30
Speaker 1: Will die from murder right over the lack of oil. Uh.
33:35
Speaker 1: If you want to know more about water, just type
33:38
Speaker 1: that magic word into the search bar how stuff works,
33:41
Speaker 1: and it will bring up a just a plethora of
33:44
Speaker 1: really interesting articles. And I said search part in there.
33:47
Speaker 1: So it's time for a listener man. Yeah, I'm gonna
33:51
Speaker 1: call this brave, brave email from a young person about depression.
33:55
Speaker 1: It's really neat. Hey, guys, my name is Brooke and
33:58
Speaker 1: I'm from Beer Area, Kentucky. Absolutely love your show. I
34:02
Speaker 1: think you're both extremely and intelligent and inspiring. I don't
34:05
Speaker 1: know about that. I've learned a lot about various topics
34:09
Speaker 1: while listening to your show and can't get enough. I
34:11
Speaker 1: wanted to email you, guys, because I wanted to get
34:13
Speaker 1: a message out to as many people as I can.
34:16
Speaker 1: I am fifteen years old, have been hospitalized three times
34:18
Speaker 1: for depression. The last time was because I attempted suicide
34:21
Speaker 1: by overdosing on trisdone. I was aware but hyperventilating when
34:27
Speaker 1: my mother found me on the bathroom floor, called nine
34:29
Speaker 1: one one and an ambulance took me to the local hospital.
34:32
Speaker 1: UH and then I was sent to a facility after
34:34
Speaker 1: recuperation for depression for a little over a week and
34:37
Speaker 1: did not get just charged until Christmas Eve. The day
34:40
Speaker 1: I attempted suicide was the day I turned my life around.
34:43
Speaker 1: Though since then I've been doing amazing and have come
34:47
Speaker 1: to the realization that harming myself was not the way
34:50
Speaker 1: to go. UH. So I wanted to tell anyone and
34:53
Speaker 1: everyone that suffers from this kind of depression to know
34:57
Speaker 1: that there is hope, and I wanted to start publicly
34:59
Speaker 1: speaking about experiences so hopefully try and motivate others so
35:03
Speaker 1: you have the same epiphany I did. I would really
35:06
Speaker 1: appreciate it if you guys read this on the air
35:09
Speaker 1: during the podcast. Thank you from Brooke. So Brooke, that
35:13
Speaker 1: is a very brave thing to do. Yeah, thanks Brooke
35:15
Speaker 1: as a fifteen year old, and really for any age
35:18
Speaker 1: to be so forthcoming about your struggle and uh to
35:21
Speaker 1: try and help people out. So thanks for that. Yeah,
35:24
Speaker 1: thank you. Um if you want to send us a
35:28
Speaker 1: letter and email, you want to say hi, you want
35:31
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35:34
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35:38
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35:42
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35:44
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35:46
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35:49
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35:52
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35:59
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36:01
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