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Welcome to ANI In the Air, Under the Tent, and Around Baltimore, your daily podcast briefing
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of all the goings ons, ins and arounds, arts and ideas, Sudbury School.
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Also today is Monday, so we have Millions Monday.
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Today is also our Halloween celebration.
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We postponed it from Friday, which was the day before Halloween because of cold wet weather,
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to today where we have windy cold weather.
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Excellent.
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So I am broadcasting underneath the big tent.
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It is pretty windy and pretty cold, but you know, it's nice.
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There's a bunch of people who are sitting out in the parking lot in the nice sunny spot.
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Under the tent is a little shady.
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I really need to rethink this catch phrase of being under the tent, but you know, maybe
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I'll just become metaphorical.
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Yeah, I like that.
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So anyway, the tent had, you know, weathered this wind fairly well, but it definitely seems
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like if we're anticipating some windy weather we should probably take it down in the future.
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I mean, this wind was fine, but probably not too much more.
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Yeah, and truth be told, you know, during the cold weather it's nice to be in the sun,
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so maybe we'll just do that.
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And we still have plenty of shade from these trees, so I don't know, I guess we'll see.
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Anyway, what else?
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So Halloween, a bunch of people dressed up in pretty cool costumes, enjoyed seeing several
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of the costumes both on Friday and today, and some modifications of these costumes.
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So that's all cool.
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As promised, I didn't wear a costume today because I just can't in all this craziness,
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but that's okay.
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I appreciate those who did.
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We did see some online people and alumni people stopping by, so it was great to see them.
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You know, staying outside of course, so that's cool.
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We had mandatory announcements.
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It was not under the tent today, instead we tried to do it inside both on Discord and
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across the intercom to mix success.
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It really does make a difference to have everybody in the same area, I think.
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But basically the announcements, there was Josh's history class announcements, an article
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club, and what else, the JC clerk for November will be Cassidy, so that's great that they
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stepped up, and thank Declan for his service over the past two months.
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Guess we'll see about doing all that, because it's Halloween celebration day.
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There's no JC today, but we'll have it tomorrow.
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Well, we also had a really cool haunted house up in the art room, so thanks to those who
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did that, it was really pretty cool.
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Some of the students went through it five, six times, and screaming all the way.
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So that's nice.
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What else we got?
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I'm not really sure what else we got.
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Oh, fire, yes.
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So last week I rebuilt the fire pit that Caroline had made several years ago, and then on Friday
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we took it for a test spin, and that went nicely, and then I think hopefully today we'll
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be able to do another fire, just trying to wait until the wind is calm enough that it
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doesn't blow the fire away, although of course fires are pretty, I mean, wind loves to feed
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fire, so there's that nice feature, but of course we don't want to burn anything down.
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Fortunately, everything's wet, so there you go.
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All righty, so I thought today for Millions Monday, I'd take a stab at wind and its energy,
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particularly thinking about a wind turbine, so this is just me trying to fumble around
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with this idea, but let's see what we can do.
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So what's the idea of a wind turbine?
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So the idea is wind is blowing through these blades, turning them, and that's moving something,
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probably some magnetic thing or something, generating electricity that then flows out.
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Now one of the basic laws of physics is conservation of energy, so even if you don't know all the
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particular mechanics of this, you know, basically the turning of the blade is what will generate
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the eventual energy that the electricity is being generated with.
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So you can get a sense of how much that energy is by figuring out basically how much air
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is flowing past the blades and at what speed, and then we use the kinetic energy formula,
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which is you take the mass of the thing and you multiply it by the velocity squared, divide
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by two because why not, and then you get your energy, your kinetic energy.
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Now of course it won't be 100% energy transfer because you've got wind coming out on the
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other side, so I have no idea what their efficiencies are, so when you've got no idea, let's go
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with 30%, one third, or maybe 50% to divide by two again, but you know, I divide by two
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once, why not divide by three next, you know, it's just fair, right?
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Okay, great.
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Okay, so how are we doing this?
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So you need to know the volume of air that passes past the blades in one second.
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So the blades form a circular disk flowing around, right, pushing around.
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Let's say they're three meters long, so fairly substantial, that's about nine or ten feet.
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And so we're going to go with meters for all of this because we want to talk about joules,
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which is what watts are based on.
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Just so you know, power is joules per, power is, you know, how much energy is flowing per
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unit of time, so watts is the energy that measures, so like 100 watt light bulb means,
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you know, a certain amount of energy flowing into it for a particular unit of time.
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Now a watt is joules per second, so that means 100 watt light bulb uses 100 joules per second.
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Okay, and a joule is something like the amount of energy it takes to raise some amount of
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water, probably a liter, one degree Celsius over some amount of time, well maybe it doesn't
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matter what the time is, it doesn't really matter.
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Anyway, joules is whatever joules is, right, great.
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So what do we got?
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So we need to know the mass, that's going past these blades, and then the speed.
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Now the speed is easy because that's just kind of told to you for the windy days.
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Today we had gusts of 50 miles an hour, so let's go with that.
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Now that's miles per hour, meters per second can be found by more or less dividing by two.
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So it's a little bit more than that, so it's maybe like 20 meters per second for 50 miles
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per hour.
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Let's go with that, 20 meters per second, great.
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That's fast.
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Okay, so 20 meters per second, that's the velocity, so velocity squared is 400, good,
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keep that number in your mind.
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Now what's the mass?
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Well to get the mass, you need to know the volume, and then you multiply by the density
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of air.
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Let's say the density of air is one kilogram per cubic meter.
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I looked it up, it seems to be roughly what it is, it's a little more than that, but whatever.
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We're just being very sloppy here.
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So one kilogram per cubic meter, so now we need to know what the volume is.
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Now the blades being three meters long means basically the circular area being swept out
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is, well it's pi r squared is the area, and r here is three, so nine times pi, and pi
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is roughly three, so that's 27, so let's round up to 30.
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So 30 square meters is the area that's being swept by these blades, and now the length,
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well I'm guessing that you get the length by how much air flows in a second, so this
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is how much stuff is flowing in a second, right?
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And so 20 meters per second means there's 20, so 20 times 30 is 600 cubic meters of
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air flowing through these blades, and now, as I said, one kilogram per cubic meter, so
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that's 600 kilograms, and then you multiply it by the velocity squared, and that was 400,
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so 400 times 600, that's four zeros, and a 24, so 240,000 joules, all right, or 240 kilojoules,
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for instance, this was kind of like energy per second, or whatever, that's 240 kilowatts,
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cool, that's a pretty good substantial sum, now I didn't divide by two for the kinetic
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energy, so that's 120 kilowatt hours, so that's sad, and then the efficiency I said maybe
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was a third, so divide by another three, which we guess would be 40 kilowatt hours, now I'm
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kind of sad, because that's not that much, but I think a house, I forget how much a house
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uses, but it's somewhere over kilowatt hours in a day or something, I don't know, maybe
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one kilowatt hour per day, I don't know, let's see, a kilowatt would be like 10, 100 watt
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light bulbs, I mean, you got some pretty big energy consumptions, maybe, maybe, I don't
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really know, five kilowatt hours, maybe a kilowatt an hour, that seems isn't much, typical
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electricity use, what do we got, well, obviously it really depends, but, ooh, a HVAC might
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use around 30 kilowatt hours in a day, ooh, water heating, ooh, could be 14 kilowatt hours,
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refrigerator, I don't know, maybe five kilowatt hours a day, man, I don't know, alright, so
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it adds up to quite a bit, so, I don't know, maybe I did a, not a great estimate here or
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something, 'cause that doesn't sound like that wind energy is doing a lot for us, eh,
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maybe I'll just buy a factor of a thousand, and then that'll make me happy, 'cause it
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really kind of feels like, well, I don't know, well, I mean, you don't have one wind turbine
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per house, alright, maybe a lot of wind turbines, maybe one wind turbine per neighborhood, that
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would be good, I don't know, anyway, well, that was my attempt, uh, pick it apart as
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you like, uh, 'cause I probably went wrong somewhere, okay, uh, anyway, well, I guess
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I could just take a look at it, uh, energy for a wind turbine, oh, wind turbine works,
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future wind turbines, how much energy does a wind turbine produce?
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Large wind turbines, eh, the world's largest wind turbine does 12 megawatts offshore energy,
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67 gigawatt-hours of wind power each day, I mean, each year, oh man, residential wind
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turbines, so stuff on top of a roof, ooh, that's about, uh, one kilowatt to ten kilowatts,
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uh, yeah, so, yeah, I feel like I might have been off by 100 to 1,000 in my computations,
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oh well, um, anyway, if you're curious, you can read all about it on those internets out
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there, alrighty, well, uh, the wind is blowing me away, so, uh, signing off, I hope this
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was somehow useful to somebody somewhere, and, uh, yeah, have a good one, bye bye.