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[Mr. Palau]

concerning super conductivity I would point you to this article that some-what recently appeared int eh economist's sceince section http://www.economist.com/node/21540385 
Super conductors have decreased in price by 90% from the 90s, really thanks to radical increases in the effeciency of HTS (High Temperture Superconducter). The most important of these advancmnets is that they have discovered a material, made form cermaics, that will superconduct at tempertures that can be acheived just by cooled nitrogen, and not liquid helium. Since most of the atmosphere is Nitrogen, the atmosphere can be used as the coolant of the superconductors.

You could have a superconducting space elevator that cools itself with atmospheric air and transmits excess heat into space, the superconductive wiring would only cost 10x as much as traditional power lines now. I say only 10x as much becasue before 80x of most superconductive materials were silver so it was way more expensive than normal copper wiring.

Of course second law of thermodyanamics would also apply ot the cooling system, making it much less effective than if that were not the case, but so long as the effeceincy is enough that the cost to get rid of the waste energy is less than the price of the energy aquired you would be able to aquire as much energy as needed. Although eventually the cost of desposing of the thermal waste would increase so you would have to increase the effeciency of the system eventaully or cap energy consumption.

I just looked at the first page of the thread and it looks like by the second post it was all about politics. If this thread is about the politics of carp infestations, and we are talking aobut energy dyanmics and politics, how offtopic are we?

[Jacob/Lee]

It's obvious what must happen: someone needs to mod carp to instantly melt upon contact with water.

[wierd]

Well.. I did ask if it was possible to derail a political topic with politics.....


I guess now we know!

Personally, I wonder how the asian carp were introduced. Is it like the snakeheads in florida, where the local asian ethnic population didn't want to pay import duties on "tasty fish", so they decided it would be ok to dump them in a pond or other waterway without contemplating that eggs are carried on the legs of waterfowl, and that (in the case with snakeheads) that they might just crawl out and migrate on their own?

I really am curious what the reason for release of a known invasive species was.

Here, we have invasive zebra mussels that infest the bilges and livewells of freshwater pleasure and fishing craft, that people just can't be bothered to inspect and properly clean, so like a dirty heroin needle spreading hepatitis, we have boats spreading lake destroying xenotics like crazy.

Carp are a "teeny" bit bigger than fishscale sized zebra mussels though.

[saltmummy626]

did you just compare carp and mussels to hepatitis?
if so, thats... pretty apt considering what is going on over there. anyway, carp are garbage fish. they eat everything, and honestly I dont think they taste very good. mostly thats probably because I dont know how to prep them properly OR they are genuinely nasty fish.

[WillowLuman]

Carp are very bony and hard to process, therefore much less valuable than native fish.

[Oliolli]

I just looked at the first page of the thread and it looks like by the second post it was all about politics. If this thread is about the politics of carp infestations, and we are talking aobut energy dyanmics and politics, how offtopic are we?

Somewhere between Bay12 average and SSE.

[Vehudur]

Just to establish this, the whole "generate power in space and beam it to earth to distribute" idea is terrible and wouldn't work.

Generating power in space and then beaming it down (or through wires in some sort of tether) would require much more power then generating it on the planet would and is extremely impractical.  A laser would be scattered very badly by the atmosphere and suffer massive losses, wires would get their asses handed to them by resistance (simple ohms law) and induction.  Not to mention the fact that we just can't concentrate a powerful laser that much over such long distances yet either.  On top of that, that large laser is going to generate a LOT of heat, likely several times the power it is emitting as a laser.  How are you going to cool it?  Your black body emitter is going to have to be city sized or it's just going to melt.  A laser just simply wouldn't be able to do the job, so that leaves us with wires in some sort of tether, but that causes other problems...

As it is, line losses are a problem over just a few thousand feet although mitigated by using much higher voltages for transmission lines.  So if you have your massive space-solar-panel-thingy beaming down 50 gigawatts to a receiving station half the day and another one on the other side of the world the other half of the day, your line losses are going to be so huge or your wires so enormous and voltages so insanely high that you're better off just building normal power plants. 

There are various tricks to mitigating this even further, but at long distances (thousands of miles) you're loosing a decently large fraction of the power you're putting into the wire, even at 350,000 or 500,000 volts.  At the vast distances from space to the surface, you're going to be putting several times more energy into the system then you are getting at the surface - and remember, that waste is creating heat somewhere, and you need to handle it.  Raising the voltage even further is more difficult then it sounds, because at that point you start running out of insulators** for it that will work.

**Yes, you still need to insulate it in space.  In fact, you need to insulate it MORE then you would in open air. This is because excess electrons can literally fly off a conductor in a vacuum or near vacuum to something that has less potential.  In fact, this is how early transistors worked.  If you can't see why this is a problem or think you have some creative work-around, you shouldn't be discussing this subject.

I just looked at the first page of the thread and it looks like by the second post it was all about politics. If this thread is about the politics of carp infestations, and we are talking aobut energy dyanmics and politics, how offtopic are we?

Somewhere between Bay12 average and SSE.

This too.  This thread is so off-topic I don't even remember what it was about and I have to go read the OP again.

[wierd]

I agree. It would be wasteful and impractical on all fronts. Sadly, that hasn't stopped politicians with "ideas!" From making equally stupid laws requiring similarly boneheaded things to be done.

I agree about line losses. That's why I said we needed an efficiency boom. Right now, we clearly and deperately need to overhaul and replace our energy distribution system, because it is:

1) wasteful
2) inconsistently implemented
3) vulnerable to serious problems
4) just not up to the task of being scaled up/able to meet future demand

Like all major infrastructure upgrades though, the powers that be see only the billshock from the construction fee and red tape, and don't see the monetary damages that doing nothing would impose.

When the powerlines glow with beautiful nitrogen incandescence from being driven at 3000% rated voltage, and bleed radio and cathode ray emissions all over, maybe they will get around to fixing them, but I wouldn't bet on it.

[Mr. Palau]

Just to establish this, the whole "generate power in space and beam it to earth to distribute" idea is terrible and wouldn't work.

Generating power in space and then beaming it down (or through wires in some sort of tether) would require much more power then generating it on the planet would and is extremely impractical.  A laser would be scattered very badly by the atmosphere and suffer massive losses, wires would get their asses handed to them by resistance (simple ohms law) and induction.  Not to mention the fact that we just can't concentrate a powerful laser that much over such long distances yet either.  On top of that, that large laser is going to generate a LOT of heat, likely several times the power it is emitting as a laser.  How are you going to cool it?  Your black body emitter is going to have to be city sized or it's just going to melt.  A laser just simply wouldn't be able to do the job, so that leaves us with wires in some sort of tether, but that causes other problems...
snip

Well you got me on the laser, after taking a second look at the options available that is the least efficient. The best choice would be microwaves, I should have gone with that at first but laser are eye-catching lol . If you guys want to go really in depth there is this article
http://www.sspi.gatech.edu/wptshinohara.pdf
from Georgia (US state not the country) tech, but I will just summarize their summery. So solar production has a theoretical efficiency limit of 70% and 30% is reflected into space (could not find % absorbed by atmosphere...). That means to be practical Space Based Solar Power (SBSP) needs to be able to wirelessly (for as veduher explained wires are impractical). Microwave transmission through an atmosphere has an efficiency of about 95% and transmission ranges of 148KMs have been achieved. If you do the math it comes out as incredibly inefficient in terms of power transmission to make it in space and microwave beam it down to you, mainly because of the small distances that you can transmit microwaves across, would require multiple transmissions in order to make it to earth. Now most of that loss obviously comes from the small distance you are able to accurately transmit microwaves over, the 95% rate is good by its self. Factor in the fact that 20-30% of energy is lost in the conversion from microwave to electricity and back, which is the real reason the retransmissions are bad because that is just from one microwave generator to an antenna, it would add up. The problem isn't really the atmosphere, microwaves in the wave lengths of 1 gigahertz to 30 gigahertz are almost unabsorbed by the atmosphere, which is why they are used for communications. The only thing holding it back from being more efficient than planet bound solar is the transmission range, if it could be transmitted over distances of 1000 KM, the length from the surface of earth from where the atmosphere really stops.

But on the subject of the laser as I said before that was a stupid mistake on my part, and I apologize. Now on the subject of the laser the one down side you didn't mention (you were quite thorough) is that you would have the same efficiency problem with photovoltaic on the ground, I.E. the increased loss of energy due to photovoltaic inability to convert light to power. Microwave to power is much more efficient.

The heat critique would still hold true for the micro wave emitter though. That would also require a large black body emitter, or be able to withstand high temperatures for short periods of time. Short periods of time because the thing doesn't operate constantly, it operates infrequently and thus would only be required to withstand high temperatures for small amounts of time.

Oh and on the subject of safety concerns, the emission within a reasonable distance (within a city block) from the receiver would only be mildly dangerous, and they would likely be built in areas as short as half a mile outside of where the energy will be consumed. Admittedly I made up the half mile mark as safe, but that’s a really conservative estimate because the microwaves are (relatively) very accurate.

Oh and all of this is without superconductors in the machines, which could likely be incorporated in them at the same time they become practical for power lines, which we have all agreed would be very, very helpful.

[WillowLuman]

So, what happens when we derail the thread to the feasibility of time travel?

[Vehudur]

A physicist dies inside.

[wierd]

FTL, causality

Pick one.

As I see it, short of becoming massless, there is no way to ftl, and as such, no way to timetravel (backwards anyway).

Relativity says that if you travel at exactly C, you will no longer experience time. Thus, you can never decellerate.

If you travel at say, 99% C, the way you experience time will be radically different than somebody outside your craft that is not. From your PoV, the universe speeds up, and you get where you are going "waaaaaaay sooner than expected." However, the rest of the universe looking in at you shows you moving at lethargic snailman speeds as you wander around in your ship.

Because of this, you could plan a "quick" jaunt around the galaxy at 99% C, take millions of years outside time to complete the journey, but only take a few years inside time.

This means traveling at any significant fraction of C makes you experience timetravel like effects.

Traveling backward in time requires using an irrational value for velocity, eg, FTL. If you do that, you violate causality. Yay!

[Vehudur]

Yep and every particle of dust you hit on the way is going to hit you like a large artillery shell, so your ship better be made of something literally unbreakable because anything larger is going to be like an atom bomb.

[wierd]

Quite right. Without a boss deflector field of some kind, single protons would tear your ship into shreds very quickly.

(Hooray for similating being hit by the high energy beam at the LHC at point blank!)

(In short, your ship needs to be able to easily deflect absurd energy particle streams if you want to ever arrive alive.)

I omitted that snafu for the sake of argument though.

[Baselope]

Is all this related somehow to the fact that these carp in real life jump and smack you in the face like a truck when you drive by them on a speed boat?  No kidding.