What-If 0130: "Snow Removal"

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MattTheTubaGuy
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What-If 0130: "Snow Removal"

Postby MattTheTubaGuy » Fri Feb 20, 2015 7:37 am UTC

Snow Removal

Well that is certainly quite a lot of snow!
At least they aren't getting earthquakes as well.
During 2011, Christchurch, New Zealand had three earthquakes above magnitude 6, and two unusually heavy snows (for Christchurch)!
Here is a 1m cube of snow I made after the first snow, with our dog jumping off it:
Image
It took most of the snow in our front yard to build this.
Some places in New England are covered in more than twice as much as this EVERYWHERE, which is just insane!

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Re: What-If 0130: "Snow Removal"

Postby Neil_Boekend » Fri Feb 20, 2015 8:20 am UTC

Apparently someone already tried to patent a device to do this.
(trigger warning for spelling and grammar enthusiasts: it seems OCR-ed, printed and OCR-ed again. Maybe there even were a few machine translations involved)
patent
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Re: What-If 0130: "Snow Removal"

Postby The Moomin » Fri Feb 20, 2015 8:59 am UTC

I always thought a good way for snow removal would be to redirect the warm car exhaust downwards around the car forming a warm blanket of air. I guess this would be useless given the amount of energy required to melt snow?

Also, those snow melters on the snow farm look to turn the snow into steam, which then rises into the air, where it could possibly form snow again and fall back down?
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Re: What-If 0130: "Snow Removal"

Postby bachaddict » Fri Feb 20, 2015 9:39 am UTC

Hi Matt! Haven't seen you on here in a while!
I'm glad I decided not to make the topic, so you could do it.

Could you collect and compact snow as you go so it's easier to deal with? Or compress it until the pressure melts it?
slinches wrote:Also, the OTC isn't a disease. In fact, it's the cure. As we all know, Time heals all wounds.

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Re: What-If 0130: "Snow Removal"

Postby Pfhorrest » Fri Feb 20, 2015 9:51 am UTC

I love footnote 2. I always want to say "rooves". "Roofs" just doesn't sound right. Unless you make it "oo" like "book" rather than "oo" like "boob", but then it sounds like you're talking about a plurality of dog-barks.
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Re: What-If 0130: "Snow Removal"

Postby speising » Fri Feb 20, 2015 10:59 am UTC

"Snow Melters"? what insanity is this? i cant imagine what they are good for, given that the melted snow will eventually re-freeze somewhere.

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Re: What-If 0130: "Snow Removal"

Postby Neil_Boekend » Fri Feb 20, 2015 12:18 pm UTC

speising wrote:"Snow Melters"? what insanity is this? i cant imagine what they are good for, given that the melted snow will eventually re-freeze somewhere.

Image
We should be using enough power to evaporate the water and have it mostly leave the area.
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Re: What-If 0130: "Snow Removal"

Postby PatTheGreat » Fri Feb 20, 2015 1:15 pm UTC

He's unfortunately got the power output of a carrier nuclear reactor wrong. The A4W plant on a carrier produces 550 megawatts of power, and each carrier has two. So to provide the energy for the snow-melter contraption, he would only need one carrier, and only slightly over one of those reactors (so total carrier output 1100 megawatts. Or maybe one A4W reactor and the smaller reactor on a submarine. That'd be cool. I work in naval nuclear propulsion on the by and by.

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Re: What-If 0130: "Snow Removal"

Postby CharlieP » Fri Feb 20, 2015 2:16 pm UTC

Pfhorrest wrote:I love footnote 2. I always want to say "rooves". "Roofs" just doesn't sound right. Unless you make it "oo" like "book" rather than "oo" like "boob", but then it sounds like you're talking about a plurality of dog-barks.


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Re: What-If 0130: "Snow Removal"

Postby Whizbang » Fri Feb 20, 2015 2:22 pm UTC

Neil_Boekend wrote:
speising wrote:"Snow Melters"? what insanity is this? i cant imagine what they are good for, given that the melted snow will eventually re-freeze somewhere.

Image
We should be using enough power to evaporate the water and have it mostly leave the area.



What about a giant fusion reactor in space that emits massive amounts of electromagnetic radiation that will warm not just our planet but the entire planetary system?

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Re: What-If 0130: "Snow Removal"

Postby Nicias » Fri Feb 20, 2015 2:55 pm UTC

Whizbang wrote:What about a giant fusion reactor in space that emits massive amounts of electromagnetic radiation that will warm not just our planet but the entire planetary system?

What about slowly releasing more and more CO2 into the atmosphere to increase its ability to block thermal radiation, thereby unbalancing the heat budget and raising average planetary temperature?

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Re: What-If 0130: "Snow Removal"

Postby Whizbang » Fri Feb 20, 2015 2:58 pm UTC

Nicias wrote:
Whizbang wrote:What about a giant fusion reactor in space that emits massive amounts of electromagnetic radiation that will warm not just our planet but the entire planetary system?

What about slowly releasing more and more CO2 into the atmosphere to increase its ability to block thermal radiation, thereby unbalancing the heat budget and raising average planetary temperature?



That would never happen. Don't be silly.

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Re: What-If 0130: "Snow Removal"

Postby Neil_Boekend » Fri Feb 20, 2015 3:00 pm UTC

Mikeski wrote:A "What If" update is never late. Nor is it early. It is posted precisely when it should be.

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Re: What-If 0130: "Snow Removal"

Postby keithl » Fri Feb 20, 2015 3:12 pm UTC

Whizbang wrote:What about a giant fusion reactor in space that emits massive amounts of electromagnetic radiation that will warm not just our planet but the entire planetary system?
Here you go:
Image
A Space Solar Power Satellite, shown here boiling the water around icebergs in the Amazon. Not shown, harmonics and Strehl effect scatter wiping out radar, satellite communication, and wifi throughout the western hemisphere. A few hundred of these babies, and Boston will be free of snow in days ... and free of non-baked humans faster.

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Re: What-If 0130: "Snow Removal"

Postby Bounty » Fri Feb 20, 2015 5:30 pm UTC

Melting seems Energy Expensive.

What about MOVING? California is in what Bostonians might call "A Wicked Drought". Would it be more energy efficient to send the Snow or Ice to California?

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Re: What-If 0130: "Snow Removal"

Postby sevenperforce » Fri Feb 20, 2015 6:01 pm UTC

Bounty wrote:Melting seems Energy Expensive.

What about MOVING? California is in what Bostonians might call "A Wicked Drought". Would it be more energy efficient to send the Snow or Ice to California?

As a bonus, the snow would surely melt on the way there!

It's the whole "most efficient way of transporting shit from coast to coast" issue which is...problematic.

If we (unwisely) ignore the cost of getting snow off the streets and into the rail cars, we are left with shipping costs alone. Using these figures, I found that the lowest rail coal shipping cost was 1.14 cents per ton-mile. It's around 2700 miles from Boston to San Francisco, so that gives you an estimated cost-per-ton of $30.77 to get water there, or $0.034 per liter, or 0.896 cents per gallon.

That's about twice as expensive as municipal water in California right now, at around 0.4 cents per gallon.

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Re: What-If 0130: "Snow Removal"

Postby keithl » Fri Feb 20, 2015 6:32 pm UTC

sevenperforce wrote:
Bounty wrote:Melting seems Energy Expensive.

What about MOVING? California is in what Bostonians might call "A Wicked Drought". Would it be more energy efficient to send the Snow or Ice to California?

As a bonus, the snow would surely melt on the way there!

It's the whole "most efficient way of transporting shit from coast to coast" issue which is...problematic.

If we (unwisely) ignore the cost of getting snow off the streets and into the rail cars, we are left with shipping costs alone. Using these figures, I found that the lowest rail coal shipping cost was 1.14 cents per ton-mile. It's around 2700 miles from Boston to San Francisco, so that gives you an estimated cost-per-ton of $30.77 to get water there, or $0.034 per liter, or 0.896 cents per gallon.

That's about twice as expensive as municipal water in California right now, at around 0.4 cents per gallon.

Love the numbers. Sadly, Massachusetts and California do not share a navigable ocean; it would be somewhat easier to shovel the snow into a gigantic barge-like kevlar sack and pull that from coast to coast. It almost makes sense to haul ice/water from the Ross Ice Shelf to Saudi Arabia that way.

But since this is the xkcd universe, we should be discussing a Transcontinental Aqueduct, at a high enough altitude to be driven by Coriolis acceleration. All we need is 100% efficient pumps for the Boston ascent and hydrogenerators at San Francisco, and 100% efficient power lines to return lift/descent energy eastward. Perhaps large rolling balls of ice would be lower friction than flowing water. The Californians could pay for the water with mission-style burritos. Let's build this and have it ready before the next big snowstorm, a century or two from now.

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Re: What-If 0130: "Snow Removal"

Postby mathmannix » Fri Feb 20, 2015 8:13 pm UTC

keithl wrote:A few hundred of these babies, and Boston will be free of snow in days ... and free of non-baked humans faster.

I read/thought "Boston baked [human] beans."
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Re: What-If 0130: "Snow Removal"

Postby SpitValve » Fri Feb 20, 2015 8:33 pm UTC

Randall's example here is pretty silly. His car is trying to melt 20 cubic metres of snow every second. Of course that's going to come out huge, he's made a frigging death ray. The problem is not really that snow takes a huge amount of energy to melt (although it does take a good bit), it's that he's trying to melt it ridiculously quickly.

Using his numbers, it takes about 2 kW of power per square metre to melt a foot of snow over a period of about an hour. That's like a small electric heater every metre - expensive, but not "three nuclear powered carriers" expensive. I imagine it takes less power if you melt the snow as it falls rather than trying to melt a full foot at once - assuming you get less than a foot per hour of snow.

After all, heated side-walks are actually pretty common in some countries, and it's not like Iceland needs a nuclear power plant on every block to keep them running.

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Re: What-If 0130: "Snow Removal"

Postby Pfhorrest » Fri Feb 20, 2015 8:57 pm UTC

keithl wrote:All we need is 100% efficient pumps for the Boston ascent

Misread this and did a double-take. "Wait, what? How do you pump an accent? ...Wouldn't it be moah efficient to transpoaht by cah? Or ah the distances involved too fah?"
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Re: What-If 0130: "Snow Removal"

Postby sevenperforce » Fri Feb 20, 2015 9:12 pm UTC

SpitValve wrote:Randall's example here is pretty silly. His car is trying to melt 20 cubic metres of snow every second. Of course that's going to come out huge, he's made a frigging death ray. The problem is not really that snow takes a huge amount of energy to melt (although it does take a good bit), it's that he's trying to melt it ridiculously quickly.

Well he did say he wanted to drive along at 55 mph.

keithl wrote:Sadly, Massachusetts and California do not share a navigable ocean

Well, thanks to climate change, they do now.

But there's an easier way. Of all the major cities hit by the current storm, Kansas City is probably the closest to California. If we ship snow by rail from KC, we only have to go 1,504 miles. Unfortunately that's still 0.499 cents per gallon, which isn't enough of an improvement to make it viable.

However, if we can get the snowmelt to the head of one of the basins leading into California, gravity will do the work for us. Of all the basins that feed into Cali, the Colorado River Basin is by far the easternmost. The easternmost point of the Colorado River Basin is just west of Boulder, Colorado. Boulder is only 622 miles from Kansas City, meaning our transportation costs drop to 0.21 cents per gallon, finally cheaper than the current costs of water in California. Success!

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Re: What-If 0130: "Snow Removal"

Postby speising » Fri Feb 20, 2015 9:22 pm UTC

SpitValve wrote:After all, heated side-walks are actually pretty common in some countries, and it's not like Iceland needs a nuclear power plant on every block to keep them running.

they sit on top of a thermal exhaust port of a power plant...

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Re: What-If 0130: "Snow Removal"

Postby sith1144 » Sat Feb 21, 2015 12:36 am UTC

Ok so Poland put jet engines on trains for deicing in the sixties and there are more modern images of jet-engines mounted on trucks but the forum flags as spam so I cant put in a link :( theres a thread on this subject at the mig-15 subforum of dcs world though, directing you there is all i can do ;)

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Re: What-If 0130: "Snow Removal"

Postby rmsgrey » Sat Feb 21, 2015 2:22 am UTC

sevenperforce wrote:However, if we can get the snowmelt to the head of one of the basins leading into California, gravity will do the work for us. Of all the basins that feed into Cali, the Colorado River Basin is by far the easternmost. The easternmost point of the Colorado River Basin is just west of Boulder, Colorado. Boulder is only 622 miles from Kansas City, meaning our transportation costs drop to 0.21 cents per gallon, finally cheaper than the current costs of water in California. Success!


Except that you're gonna have trouble convincing anyone to pay for the water that comes in that way...

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Re: What-If 0130: "Snow Removal"

Postby ManaUser » Sat Feb 21, 2015 4:49 am UTC

I don't live any place where I need to worry about this, but if I did, melting 17x9x1' snow will a gallon of gas actually sounds pretty tempting. That would be just right for clearing driveways. And gas is still pretty cheap right now...

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Re: What-If 0130: "Snow Removal"

Postby sevenperforce » Sat Feb 21, 2015 7:44 am UTC

rmsgrey wrote:
sevenperforce wrote:However, if we can get the snowmelt to the head of one of the basins leading into California, gravity will do the work for us. Of all the basins that feed into Cali, the Colorado River Basin is by far the easternmost. The easternmost point of the Colorado River Basin is just west of Boulder, Colorado. Boulder is only 622 miles from Kansas City, meaning our transportation costs drop to 0.21 cents per gallon, finally cheaper than the current costs of water in California. Success!


Except that you're gonna have trouble convincing anyone to pay for the water that comes in that way...

I'm sure the municipal corporation that pulls water out of the Colorado River to give to residents will be thrilled to have their flow dramatically increased.

Or less dramatically.

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Re: What-If 0130: "Snow Removal"

Postby bachaddict » Sat Feb 21, 2015 9:48 am UTC

How much anti-water would I have to sprinkle on snow to create enough heat to melt all of it?
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Re: What-If 0130: "Snow Removal"

Postby SuperSteve » Sat Feb 21, 2015 5:13 pm UTC

bachaddict wrote:Hi Matt! Haven't seen you on here in a while!
I'm glad I decided not to make the topic, so you could do it.

Could you collect and compact snow as you go so it's easier to deal with? Or compress it until the pressure melts it?


No. It weighs too much to collect it. The car would not be able to move.

Compressing it would take too much energy.

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Re: What-If 0130: "Snow Removal"

Postby SuperSteve » Sat Feb 21, 2015 5:17 pm UTC

PatTheGreat wrote:He's unfortunately got the power output of a carrier nuclear reactor wrong. The A4W plant on a carrier produces 550 megawatts of power, and each carrier has two. So to provide the energy for the snow-melter contraption, he would only need one carrier, and only slightly over one of those reactors (so total carrier output 1100 megawatts. Or maybe one A4W reactor and the smaller reactor on a submarine. That'd be cool. I work in naval nuclear propulsion on the by and by.


But he was calculating for a 9 foot wide path. An aircraft carrier is wider than 18 feet [citation needed], so the energy required to clear a path for it would be more than the two reactors produce.

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Re: What-If 0130: "Snow Removal"

Postby SuperSteve » Sat Feb 21, 2015 5:23 pm UTC

What if all the cars were equipped the same?

You don't need to give each car the ability to melt very much snow.

Instead, each car just needs to melt the snow that landed during the few seconds after the previous car drove over the same section of road.

The energy requirement that was calculated for driving 55 mph after a snowfall assumes that one car has to remove all the snow. But if the snow falls over the course of a few hours, and cars go by every few seconds, then each car needs to melt only 1/3600th of the snow.

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Re: What-If 0130: "Snow Removal"

Postby SuperSteve » Sat Feb 21, 2015 9:50 pm UTC

sevenperforce wrote:
Bounty wrote:Melting seems Energy Expensive.

What about MOVING? California is in what Bostonians might call "A Wicked Drought". Would it be more energy efficient to send the Snow or Ice to California?

As a bonus, the snow would surely melt on the way there!

It's the whole "most efficient way of transporting shit from coast to coast" issue which is...problematic.

If we (unwisely) ignore the cost of getting snow off the streets and into the rail cars, we are left with shipping costs alone. Using these figures, I found that the lowest rail coal shipping cost was 1.14 cents per ton-mile. It's around 2700 miles from Boston to San Francisco, so that gives you an estimated cost-per-ton of $30.77 to get water there, or $0.034 per liter, or 0.896 cents per gallon.

That's about twice as expensive as municipal water in California right now, at around 0.4 cents per gallon.


What if we send it through pipes? That's much cheaper than rail. (Building the pipelines would be expensive, but once the infrastructure is in place, all you need to purchase is energy for the pumps.)

On the other hand, it's not clean enough to use for drinking water. They aren't even allowed to dump it in the ocean, because it's not clean enough. But it might be useful for watering lawns.

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Re: What-If 0130: "Snow Removal"

Postby SuperSteve » Sat Feb 21, 2015 9:58 pm UTC

keithl wrote:
sevenperforce wrote:
Bounty wrote:Melting seems Energy Expensive.

What about MOVING? California is in what Bostonians might call "A Wicked Drought". Would it be more energy efficient to send the Snow or Ice to California?

As a bonus, the snow would surely melt on the way there!

It's the whole "most efficient way of transporting shit from coast to coast" issue which is...problematic.

If we (unwisely) ignore the cost of getting snow off the streets and into the rail cars, we are left with shipping costs alone. Using these figures, I found that the lowest rail coal shipping cost was 1.14 cents per ton-mile. It's around 2700 miles from Boston to San Francisco, so that gives you an estimated cost-per-ton of $30.77 to get water there, or $0.034 per liter, or 0.896 cents per gallon.

That's about twice as expensive as municipal water in California right now, at around 0.4 cents per gallon.

Love the numbers. Sadly, Massachusetts and California do not share a navigable ocean; it would be somewhat easier to shovel the snow into a gigantic barge-like kevlar sack and pull that from coast to coast. It almost makes sense to haul ice/water from the Ross Ice Shelf to Saudi Arabia that way.

But since this is the xkcd universe, we should be discussing a Transcontinental Aqueduct, at a high enough altitude to be driven by Coriolis acceleration. All we need is 100% efficient pumps for the Boston ascent and hydrogenerators at San Francisco, and 100% efficient power lines to return lift/descent energy eastward. Perhaps large rolling balls of ice would be lower friction than flowing water. The Californians could pay for the water with mission-style burritos. Let's build this and have it ready before the next big snowstorm, a century or two from now.


The lack of a shared ocean is not a problem. Ships can get from Boston to California, and so can giant sacks or whatever you are proposing. At this time of year, the best route is through the Panama Canal. (There is another route that goes between Canada and the polar ice cap, but it's only useful in the summer, because it's blocked by ice in winter. There is also a much longer route which requires going through the Straits of Magellan or around Cape Horn.)

An aqueduct is viable. We have pipelines that carry fossil fuel, so there is no reason that they can't carry water.

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Re: What-If 0130: "Snow Removal"

Postby hamjudo » Sun Feb 22, 2015 9:52 pm UTC

I calculate that it would take at least 4.7 gigawatts of heat energy to remove a foot of snow 9 feet wide at 55 MPH. The 335 J/gram only applies when the vehicle is going slow enough that it can melt all of the ice without vaporizing any of it. In the real world, snow is a very good insulator. A little bit of heat will melt the exposed surface slowly, a lot of heat will vaporize the exposed surface quickly. The steam from the vaporized snow will penetrate some, so the flamethrower doesn't have to vaporize it all, just most of it. I will generously assume that this process only needs to vaporize 90% of the snow.

I will just pretend that our process for vaporizing the snow is essentially magic, and once the snow is vaporized, it stops absorbing any more energy, despite being between a multigigawatt heater, and the heater's target. This would be an excellent experiment for someone else to perform. So once again, my number is going to be too low.

I will assume that in order to melt the last 10% of the snow in a timely way, I will assume that 90% of the snow will end up being vaporized. Some percentage of the melted snow will end up well above the freezing point, but I will ignore that.

To vaporize snow slowly, it takes 335 Joules to melt it, 418 joules to get it to the boiling point and 2257 joules to vaporize it, for a grand total of 3010 joules per gram vaporized. Doing it quickly still takes 3010 joules per gram, but it does it all in one step.

Since we are only vaporizing 90% of the snow, it takes 2709 joules to vaporize 0.9 grams. It will take 33 joules to melt 0.1 grams, for a total of 2742 joules per gram.

Or 4.7 gigawatts.

Corrections are welcome, my cats were "helping" me, so I probably got a few numbers wrong. (In the unlikely event that I got all of the math correct, please let me know that too. It's rare, but it makes me happy.)

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Re: What-If 0130: "Snow Removal"

Postby Neil_Boekend » Mon Feb 23, 2015 6:57 am UTC

Last Saturday night my brother and I were wondering what the energy requirements would be to bore a tunnel through the snow by compressing the snow sideways (naively assuming an infinitely thick layer of fluffy snow).
One design would be something like a cone like head and a cylinder body with rubber continuous tracks on it to compress the snow as it moves through it.
The other design we came up with is a car with a large speaker array on it. The speaker array would create sound waves to compress the snow.

Thoughts?
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Re: What-If 0130: "Snow Removal"

Postby MattTheTubaGuy » Mon Feb 23, 2015 9:07 am UTC

bachaddict wrote:How much anti-water would I have to sprinkle on snow to create enough heat to melt all of it?

Assuming you just want to melt the snow, the enthalpy of fusion for water is 333,550 J/kg

dividing this by c2, and dividing by two (equal amounts of matter and anti matter are annihilated) you would need 1.86 x 10-12kg of anti snow to melt 1 kg of snow.

The mass of a snowflake is about 3 x 10-6 kg, so one anti-snowflake would produce enough energy to melt over 1600 tonnes of snow!
In reality, it would probably just create a huge explosion, of the order of 129 tons of TNT!
If the density of snow is about 100 kg/m3, and the snow is 30cm (1 foot) deep, this would be enough energy to melt 53890 square metres, or about 13.5 acres, or 5.4 hectares.
To melt 1 square kilometre of 30cm deep snow, you would only need 19 anti-snowflakes!
I'm pretty sure I have done the calculations correctly. I will check them again tomorrow when I am more awake.

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Re: What-If 0130: "Snow Removal"

Postby AEB » Tue Feb 24, 2015 4:54 pm UTC

keithl wrote:
sevenperforce wrote:
Bounty wrote:Sadly, Massachusetts and California do not share a navigable ocean; it would be somewhat easier to shovel the snow into a gigantic barge-like kevlar sack and pull that from coast to coast. It almost makes sense to haul ice/water from the Ross Ice Shelf to Saudi Arabia that way.


Frederic Tudor used to do something like that. He shipped ice from Boston to the Caribbean, helping to spawn US imports of bananas and US exports of tourists (on cruise ships), too. So maybe exporting the snow isn't so off the mark...

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Re: What-If 0130: "Snow Removal"

Postby gmalivuk » Tue Feb 24, 2015 7:57 pm UTC

speising wrote:"Snow Melters"? what insanity is this? i cant imagine what they are good for, given that the melted snow will eventually re-freeze somewhere.
Even if all of it promptly re-froze as ice, it would be an advantage due to the 90% volume reduction.

SpitValve wrote:Randall's example here is pretty silly. His car is trying to melt 20 cubic metres of snow every second. Of course that's going to come out huge, he's made a frigging death ray. The problem is not really that snow takes a huge amount of energy to melt (although it does take a good bit), it's that he's trying to melt it ridiculously quickly.

Using his numbers, it takes about 2 kW of power per square metre to melt a foot of snow over a period of about an hour. That's like a small electric heater every metre - expensive, but not "three nuclear powered carriers" expensive. I imagine it takes less power if you melt the snow as it falls rather than trying to melt a full foot at once - assuming you get less than a foot per hour of snow.
Sure, though it takes the same amount of total energy, which is quite substantial however you parcel it out.

After all, heated side-walks are actually pretty common in some countries, and it's not like Iceland needs a nuclear power plant on every block to keep them running.
Yeah, because they use geothermal energy.

Also, how much does it actually snow in Reykjavik? My guess would be less than Boston on average, and considerably less than Boston this year.
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FunkyTuba
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Re: What-If 0130: "Snow Removal"

Postby FunkyTuba » Wed Feb 25, 2015 12:04 am UTC

Would it be better to point the microwaves down at the pavement? Could you heat the concrete or asphalt and cause melting? Adding steel wool would probably help.

You'd probably have to worry about re-freezing. What else?

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sevenperforce
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Re: What-If 0130: "Snow Removal"

Postby sevenperforce » Wed Feb 25, 2015 3:44 pm UTC

FunkyTuba wrote:Would it be better to point the microwaves down at the pavement? Could you heat the concrete or asphalt and cause melting?

Total energy is still the same. You'd have better luck, though, if you were able to lower the melting point of the snow and ice. Perhaps if you spread some sort of ionic compound on your pavement which would serve to change the melting point...sodium chloride, perhaps?

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Re: What-If 0130: "Snow Removal"

Postby GreenTom » Wed Feb 25, 2015 4:43 pm UTC

PatTheGreat wrote:He's unfortunately got the power output of a carrier nuclear reactor wrong. The A4W plant on a carrier produces 550 megawatts of power, and each carrier has two. So to provide the energy for the snow-melter contraption, he would only need one carrier, and only slightly over one of those reactors (so total carrier output 1100 megawatts. Or maybe one A4W reactor and the smaller reactor on a submarine. That'd be cool. I work in naval nuclear propulsion on the by and by.


I think he confused MWt and MWe. Melting snow seems like a great application of waste heat...after all, there' s not much else you can do with a 40F exhaust stream. The waste heat from Mystic alone should be able to melt over 1000 ft^3/sec, or, in Randal's always brilliant units, about 225 lane-foot-miles per hour. Or, if the snow is falling at 1 inch/hour, it could keep over a square mile melted.


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