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[Pwnzerfaust]

That's exactly my point. It's a closed system, therefore entropy in it will necessarily increase, on the whole. Not disagreeing with you at all there.

Ah, kay, sorry, I misunderstood.

[Muz]

Ah, Bay 12. Someone writes an interesting post on reality. Less than 5 posts later, people decide that reality is inefficient, proposes a semi-impossible method. Then everyone backs it up from stuff they learned from sci-fi and the Internet. Every scientific thread on B12 then seems to derail into semi-fictional astrophysics.

[Pathos]

Ah, Bay 12. Someone writes an interesting post on reality. Less than 5 posts later, people decide that reality is inefficient, proposes a semi-impossible method. Then everyone backs it up from stuff they learned from sci-fi and the Internet. Every scientific thread on B12 then seems to derail into semi-fictional astrophysics.

Actually, it's not really semi-fictional. The entropic death of the universe is the most likely cause of the end of the universe, judging by what we can tell by the expandation of the universe ( we thought we'd reach 0 speed and then start moving back towards the centre, in the past, now not so much ). It's gonna be a LONG time, and I personally refuse to believe that it'll be the final death.

Of course, that's merely due to my "cuckoo" idea that systems of order always tend towards entropy, and entropy always tends towards systems of order. Eventually, of course.

[Virex]

Of course, that's merely due to my "cuckoo" idea that systems of order always tend towards entropy, and entropy always tends towards systems of order. Eventually, of course.

That last one's probably contradicting thermodynamics (though you might not care), since a system will always tend to minimise it's Gibbs free energy. Said energy is defined as H - TS, with H being the enthalpy (energy ascociated with thermodynamical events such as melting, reactions etc), T is the temperature and S is the entropy. If you've got a system with a lot of chaos, he only way you're going to get order is through an event that has a large negative enthalpy. the reverse is true as well. If the enthalpy of an entropy (chaos) reducing event is too low, the system will tend towards chaos. So systems only tend towards order if there's a force capable of counteracting it's normal tendency towards chaos.

[Lord Dakoth]

So systems only tend towards order if there's a force capable of counteracting it's normal tendency towards chaos.

Not a problem if one accepts the Big Bang as a plausible event.

[sneakey pete]

A little bit of trivia here that i'm mainly bringing to you due to having just done some stuff about it for uni.

The average Rankine cycle has a thermal efficiency of around 40%, with some places getting 45% from memory. (a rankine cycle is your standard powerplant: pump some water up to high pressure, heat it so it turns into steam, send it throuhg a turbine to generate work, and cool the stuff that comes out of the turbine to send back to the pump). An efficiency of 40% means that, if you put 100MW of heat into the water heating it, you'll get 40MW* of that out as electrical power from the turbine and 60MW will be released into the enviroment via the cooling tower.

*this of course assumes a perfect transfer of heat, which is never the case. However it means that 60% of the coal we burn is really just going into heating the air around powerplants. Now, if we built a similar powerplant with the sun reflected from mirrors to heat up water, we could be using 40% of so of the suns energy (again, assuming everything works  perfectly, which it won't quite). Using sodium as the working fluid instead and storing it like in the OP won't actually increase the efficiency, but will just add to the ability to store energy, which is nice.

However, its limited to the mid 40's% A little bit of improvement may be able to be made over time, however, your always going to be stuck with efficiencies around that area. Photovoltic cells, on the other hand, are increasing in efficiency all the time, wiht the best being in the mid 30's% from memory. When a 50% efficient solar cell (and a decent battery system) becomes available for a fair price, it'll make plants like the one in the Op completely useless and inefficient.

[Shades]

However, its limited to the mid 40's% A little bit of improvement may be able to be made over time, however, your always going to be stuck with efficiencies around that area. Photovoltic cells, on the other hand, are increasing in efficiency all the time, wiht the best being in the mid 30's% from memory. When a 50% efficient solar cell (and a decent battery system) becomes available for a fair price, it'll make plants like the one in the Op completely useless and inefficient.

With respects to solar power in general, conversion efficiency isn't really that relevant. It's cost per unit watt that is important. A more efficient cell doesn't collateral to better cost per unit if it's manufacturing costs and lifetime maintenance costs also increase.

Being that there is something in the order of 90 petawatts of solar energy hitting the earth and we only use around 15-20 terawats we can already get all the power we need from the sun. Its just a matter of cost.

[darkrider2]

Scientific American did this article on Methane Carbonate or something can't remember the name. It was basically a kind of Ice that could be melted and used for fuel, but they had problems utilizing it because they had to find a way to pump it to the surface and melt it and store it. Can't remember all the details.

Then there was this bacterium that lived in a water tank and when you fed it sugarcane, it would eventually crap out petroleum.

Yeah there's a lot of interesting stuff in there...

[bjlong]

So systems only tend towards order if there's a force capable of counteracting it's normal tendency towards chaos.

Not a problem if one accepts the Big Bang as a plausible event.

No. Bad. The Big Bang didn't reduce entropy, or such--it was the origin of all space, time, matter and energy. Without the Big Bang, space and time wouldn't have existed, so physics (as we know them) wouldn't have existed. Therefore, discussing entropy and such is a fallacy.

A little bit of trivia here that i'm mainly bringing to you due to having just done some stuff about it for uni.

The average Rankine cycle has a thermal efficiency of around 40%, with some places getting 45% from memory. (a rankine cycle is your standard powerplant: pump some water up to high pressure, heat it so it turns into steam, send it throuhg a turbine to generate work, and cool the stuff that comes out of the turbine to send back to the pump). An efficiency of 40% means that, if you put 100MW of heat into the water heating it, you'll get 40MW* of that out as electrical power from the turbine and 60MW will be released into the enviroment via the cooling tower.

*this of course assumes a perfect transfer of heat, which is never the case. However it means that 60% of the coal we burn is really just going into heating the air around powerplants. Now, if we built a similar powerplant with the sun reflected from mirrors to heat up water, we could be using 40% of so of the suns energy (again, assuming everything works  perfectly, which it won't quite). Using sodium as the working fluid instead and storing it like in the OP won't actually increase the efficiency, but will just add to the ability to store energy, which is nice.

However, its limited to the mid 40's% A little bit of improvement may be able to be made over time, however, your always going to be stuck with efficiencies around that area. Photovoltic cells, on the other hand, are increasing in efficiency all the time, wiht the best being in the mid 30's% from memory. When a 50% efficient solar cell (and a decent battery system) becomes available for a fair price, it'll make plants like the one in the Op completely useless and inefficient.

Interesting idea, but this really isn't the problem. Put simply, we need a cost-effective way to store energy so that we can still turn on light bulbs when the sun goes out. Even if we neglect manufacturing costs, this is pretty much the reason why solar power isn't universally used.

(Also, assuming that we can come up with batteries and better cells isn't that great of a practice--we might find out that we can only get 15% efficiency. Still, that's far more than necessary, as Shades pointed out.)

Scientific American did this article on Methane Carbonate or something can't remember the name. It was basically a kind of Ice that could be melted and used for fuel, but they had problems utilizing it because they had to find a way to pump it to the surface and melt it and store it. Can't remember all the details.

Then there was this bacterium that lived in a water tank and when you fed it sugarcane, it would eventually crap out petroleum.

Yeah there's a lot of interesting stuff in there...

Very interesting! Do you happen to know the name of the article?

[sneakey pete]

A little bit of trivia here that i'm mainly bringing to you due to having just done some stuff about it for uni.

The average Rankine cycle has a thermal efficiency of around 40%, with some places getting 45% from memory. (a rankine cycle is your standard powerplant: pump some water up to high pressure, heat it so it turns into steam, send it throuhg a turbine to generate work, and cool the stuff that comes out of the turbine to send back to the pump). An efficiency of 40% means that, if you put 100MW of heat into the water heating it, you'll get 40MW* of that out as electrical power from the turbine and 60MW will be released into the enviroment via the cooling tower.

*this of course assumes a perfect transfer of heat, which is never the case. However it means that 60% of the coal we burn is really just going into heating the air around powerplants. Now, if we built a similar powerplant with the sun reflected from mirrors to heat up water, we could be using 40% of so of the suns energy (again, assuming everything works  perfectly, which it won't quite). Using sodium as the working fluid instead and storing it like in the OP won't actually increase the efficiency, but will just add to the ability to store energy, which is nice.

However, its limited to the mid 40's% A little bit of improvement may be able to be made over time, however, your always going to be stuck with efficiencies around that area. Photovoltic cells, on the other hand, are increasing in efficiency all the time, wiht the best being in the mid 30's% from memory. When a 50% efficient solar cell (and a decent battery system) becomes available for a fair price, it'll make plants like the one in the Op completely useless and inefficient.

Interesting idea, but this really isn't the problem. Put simply, we need a cost-effective way to store energy so that we can still turn on light bulbs when the sun comes out. Even if we neglect manufacturing costs, this is pretty much the reason why solar power isn't universally used.

(Also, assuming that we can come up with batteries and better cells isn't that great of a practice--we might find out that we can only get 15% efficiency. Still, that's far more than necessary, as Shades pointed out.)

Yeah, i know there's a need for batteries, and i certainly agree that its a cost per watt that's much more important since, like has been said, there's plenty of sunlight to go around. right now there's some unis in australia working on printable solar cells with efficiencies in the range of 10-12%, but i'm really not sure on what sort of cost that they've acheived at this stage.

[Pwnzerfaust]

So systems only tend towards order if there's a force capable of counteracting it's normal tendency towards chaos.

Not a problem if one accepts the Big Bang as a plausible event.

At the big bang, time zero if you will, the entropy of the universe was zero, since everything had nearly infinite potential energy. From the moment the big bang occurred, the total potential energy in the universe has been decreasing. Nothing in the big bang theory contradicts the constant increase of entropy.

[G-Flex]

Very interesting! Do you happen to know the name of the article?

I don't know about that article specifically, but it's methane clathrate ("methane carbonate" wouldn't make much sense ), which is basically bits of methane trapped inside an ice lattice.

[Ampersand]

You know, we might not even need to bother with this conversation much at all if we just started using candles.

[kuro_suna]

Then there was this bacterium that lived in a water tank and when you fed it sugarcane, it would eventually crap out petroleum.

Yeah there's a lot of interesting stuff in there...

That's old news, the current big advancement is that cellulose is just a bunch of sugar molecules bound together. If you used bioengineering to combine DNA from bacterial that produce ethanol and bacteria that can digest cellulose you could make gasoline from things like lawn clipping, scrap wood, leaves and straw.

[Zombie]

Then there was this bacterium that lived in a water tank and when you fed it sugarcane, it would eventually crap out petroleum.

Yeah there's a lot of interesting stuff in there...

That's old news, the current big advancement is that cellulose is just a bunch of sugar molecules bound together. If you used bioengineering to combine DNA from bacterial that produce ethanol and bacteria that can digest cellulose you could make gasoline from things like lawn clipping, scrap wood, leaves and straw.

Or the fat in the legs of this lady I keep seeing on the bus. Yuck.

Oh wait, celluLOSE... Sorry, she's just got celluLITE.