Biofuels are not the answer.

[RobbieThe1st]

Fresh water really isn't that much of a problem.  If Israel can separate the salts and minerals in the dead sea from each other, then we sure as hell can separate minerals from water.

I don't think their methodology will work for us, since it involves putting the water/mineral solution in large shallow pools with a  high surface area to volume ratio, and letting the water evaporate.

For the algae power source... I was watching a special on power sources on Discovery a while ago, and there's a power plant in... Texas? that is experimenting on growing algae as a source of oil.  That's right, oil.  Apparently, the algae they are growing can be processed into a sort of crude oil, and are grown in vertical plastic cylinders that only require aeration and a fresh water feed(and probably enough other food to grow).

As I said:

Hm... Plant wise, how about Algae? As anyone with a fish tank or even a computer water-cooling system knows, Algae grows just about anywhere there is light and heat. Of course, for mass production, you would need some source of food for it.

Light wise isn't a problem; just use vats that are open to the top/have a transparent cover,.
Heat wise, well, how about nuclear reactor waste? Everyone says its such a problem to get rid of, and is radioactive for a *very* long time, how about having a couple underground tanks with reactor waste, you have some water cycling through it which goes through a heat exchanger to transfer the heat into the vats.
Food wise, if we are talking about using it only for fuel, what about human waste? Cities have *lots* to get rid of, and you wouldn't need much, plus, by the time the algae-oil got to your tank, it would be pretty much harmless, at least disease wise.

Once you implement this on a *large* scale, it would definitely produce lots of oil, and the cost would be virtually nothing. It would take care of some human waste, use the power of spent nuclear power plant fuels, and produce lots of oil!

You could also use something like this for human food(soylent green style!), but you would need a cleaner food source, but that wouldn't be all that hard.

-RobbieThe1st's cynical views

Of course, if we could just get some powerful heat to electricity conversion device that works at room temperature, all our energy problems would be solved.
At worst, you could take a whole lot of these devices(would be better if they were "active" energy generation, such that they could remove enough heat to lower the surrounding temperature, as then you could turn a few deserts into cold deserts which produce lots of electricity!

Solar and wind wise, things would be much more practical if each house had its own energy generation system: No transmission losses, no power grids to cause problems, and not much, if any wasted space(we have these large roofs, they should be producing energy!).

-RobbieThe1st

[superluser]

Fresh water really isn't that much of a problem.  If Israel can separate the salts and minerals in the dead sea from each other, then we sure as hell can separate minerals from water.

Yes.  Very expensively.  I'd much rather spend that money on anything else.

Also, there are other sources of food other than fish, if the fish go, hey, everyone will just have to eat something else.

I'm sure we can find something else to eat, but aren't you in the least bit fazed by the possibility that there will be no more fish in the world?

in the netherlands they've installed a massive wind farm on water, which saves precious land being taken up by the mammoth wind turbines.

Copenhagen, as well.

The US, too, if we can get Teddy Kennedy to shut up about how it depreciates his land value.

greenies go on about how solar energy is the answer, but really, in any practical sense, it isn't.

I'd like to say that this is changing, but I think it's actually getting worse.  I hear that California recently provided incentives for home solar panel use.

[Alondro]

New designs on nuclear power plants solve many of the meltdown and waste problems.  My father has done work decommissioning old plants and is always looking at new designs.  The new types would have standardized parts, instead of the stupidity in the US of having nearly every plant unique, and thus the parts have to be designed for only that one particular plant, making replacement parts absurdly expensive.  They are much smaller, and though they don't produce as much power, you can build several of them more cheaply than one of the big expensive ones.

They cannot melt down.  The nuclear fuel pellets are never close enough to achieve critical mass, and the failsafe system for any 'just in case' occurrences is gravity fed, versus injection, and thus cannot simply stop working.  Plus, the new design of the fuel pellets makes them much easier to remove and reprocess, retrieving almost all the remaining uranium for re-use.  This leads to much less waste material.

The only problem is that we'd have only 200 years of power if we switched all electricity production to nuclear.  Then we'd run out of known uranium deposits.  But still, that's 200 years to hopefully find something that will work indefinitely, and 200 years of lower CO2... not that I care about global warming.  My house and my grandmother's down the street would be on beach front property in a subtropical climate if the sea rose, as we're on the NJ central ridge (a peninsula).  Heh heh, my property values would skyrocket!   

[Tezkat]

Once more, the simplest answer is getting rid of humans.  And to make that environmentally sound, they should be fed to lions, tigers and polar bears.   

That is not an environmentally sound solution to the overpopulation problem. There are hardly enough lions, tigers, or bears left in the world to consume that many humans, and essentially domesticating them with free food would impair their natural survival habits and disrupt their native ecosystems.

Fresh water really isn't that much of a problem.  If Israel can separate the salts and minerals in the dead sea from each other, then we sure as hell can separate minerals from water.

Desalination, even with the newer and more efficient reverse osmosis technologies, consumes eight times as much energy as reclamation, and that doesn't even count the costs of transportation or waste disposal. Are you suggesting that people build pipes from the coast to water crops in the middle of the country when the water tables there drop below usable levels? City planners around the world are worried about their fresh water supplies because they know how much they're using, they know how much they have available, and they know that the former is going up while the latter is going down. Bringing water in from elsewhere is expensive and merely offloads the problem to the next guy down the line. Your "solution" involves playing a giant game of whack-a-mole with the country's water and energy supplies.

Also, there are other sources of food other than fish, if the fish go, hey, everyone will just have to eat something else.

It's not just that there won't be anymore fish. There won't be any more of the things that eat the fish, or the things that eat them. And potentially bad things that the fish used to eat will flourish unchecked.

Besides, without fish, there would be no sushi. And then Tezkat would be a sad kitty.

Of course, if we could just get some powerful heat to electricity conversion device that works at room temperature, all our energy problems would be solved.
At worst, you could take a whole lot of these devices(would be better if they were "active" energy generation, such that they could remove enough heat to lower the surrounding temperature, as then you could turn a few deserts into cold deserts which produce lots of electricity!

There's a little thing called the Second Law of Thermodynamics getting in the way of that idea. Entropy doesn't move in that direction--heat is a waste product of energy production and consumption. Cooling something below the level of its surroundings consumes energy. Just take a look at your electricity bill after running an air conditioner all summer.

Solar and wind wise, things would be much more practical if each house had its own energy generation system: No transmission losses, no power grids to cause problems, and not much, if any wasted space(we have these large roofs, they should be producing energy!).

-RobbieThe1st

In the entirety of their useful lifespan (and we're talking about more than a decade here), current solar panel technologies barely recoup the energy put into manufacturing them. Like hydrogen, solar power is not really a way to save or generate energy; it's merely a relatively "green" way of storing energy and transporting it to areas where it can be used without dependence on an electrical grid.

Solar and wind power also have issues with the variability (not to mention intermitency) of their energy production (in both time and space), which may not (indeed, frequently doesn't) follow the pattern of consumption. While those aren't insurmountable deployment issues, they do present a strong case against the practicality of gridless homes and businesses.

[llearch n'n'daCorna]

Tidal power systems -might- fill some of the gap. But again, they depend on numerous variables being just right...

[Valynth]

I'm not saying we -should- desalinize water, I'm saying we'd do that before killing each other for sake of "saving the race."

[Arcalane]

Tidal power systems -might- fill some of the gap. But again, they depend on numerous variables being just right...

Much like solar and wind power. No wind? No power. Too cloudy? No power.

I have to agree with the comments about no more fish. See, the planet is a delicate thing. Ecosystems aren't just something you can take apart like a child's toy. You remove the fish, and things that rely on those fish die. Then things that rely on the things that relied on the fish die. Then the things that relied on the fish to keep under control flourish out of control and become a serious problem for everything else. Look at the predator/prey cycles. Remove the predator entirely. What happens? The prey has nothing to curb it's populations.

Ironically, I think that's pretty much what has happened with us. We have hardly any natural predators any more. The only things reducing our numbers are human stupidity (perhaps the only major "predator") and poor living conditions or the inevitable point at which our internal organs pass their expiration date. Thus we spread and thrive.

[Valynth]

Oh?  So this situation has only occurred within human times?  I seem to recall that such extinctions occurred long before Humans came to be.

The world will change, yes, but we will also change to survive as we have done since the very begining.  After all, the earth is a far from stable place.

[Arcalane]

That doesn't mean it should be encouraged. Our presence is causing adverse effects, or acceleration of the process, which is not ideal.

[Tezkat]

Oh?  So this situation has only occurred within human times?  I seem to recall that such extinctions occurred long before Humans came to be.

The world will change, yes, but we will also change to survive as we have done since the very begining.  After all, the earth is a far from stable place.

That they have. And it didn't go so well for creatures around at the time, either.

Remember that our species, and those upon which we feed (and so on down the line), have spent many thousands of years adapting to and optimizing for our environments. When human intervention drastically changes the parameters of said environment, Bad Things can happen to all of the organisms dependent on said ecosystems. Although life will go on, as it is wont to do, significant recoveries will not be evident in the scale of human lifetimes. Our quality of life would drop... due largely to factors which we seem able but unwilling to prevent.

Regardless, the special effort we're now making to drive all these tasty critters to extinction does not represent a viable long-term business model--it's merely a race to use up scarce resources before the next guy does.

[Valynth]

Show me a resource that isn't scarce by economic definitions (it commands a price by having a limited supply at one time) and I shall declare you god.

There is an answer to this situation of the fish, but no body wants to acctually work on it so they just sit around and whine about the problem all the while buying the fish coming from the very industry they're whining about.

The answer is simpler than one would think (geee, I wonder where we grow and raise animals for human consumption.... oh wait).

[RobbieThe1st]

Of course, if we could just get some powerful heat to electricity conversion device that works at room temperature, all our energy problems would be solved.
At worst, you could take a whole lot of these devices(would be better if they were "active" energy generation, such that they could remove enough heat to lower the surrounding temperature, as then you could turn a few deserts into cold deserts which produce lots of electricity!

There's a little thing called the Second Law of Thermodynamics getting in the way of that idea. Entropy doesn't move in that direction--heat is a waste product of energy production and consumption. Cooling something below the level of its surroundings consumes energy. Just take a look at your electricity bill after running an air conditioner all summer.

Well, I have to disagree with you; Just look at thermocouples. The problem is, they work fine at high temperatures, but you don't get very much at all at room temperatures.
They are working on better ones, but they aren't to that point yet.

Solar and wind wise, things would be much more practical if each house had its own energy generation system: No transmission losses, no power grids to cause problems, and not much, if any wasted space(we have these large roofs, they should be producing energy!).

-RobbieThe1st

In the entirety of their useful lifespan (and we're talking about more than a decade here), current solar panel technologies barely recoup the energy put into manufacturing them. Like hydrogen, solar power is not really a way to save or generate energy; it's merely a relatively "green" way of storing energy and transporting it to areas where it can be used without dependence on an electrical grid.

Solar and wind power also have issues with the variability (not to mention intermitency) of their energy production (in both time and space), which may not (indeed, frequently doesn't) follow the pattern of consumption. While those aren't insurmountable deployment issues, they do present a strong case against the practicality of gridless homes and businesses.

Well, my point was that a central large solar power plant is less efficient than a bunch of house-hold systems, if only because with a house system you can use your roof for it.

I have a bit of experience in off-grid systems; For the first 10 or so years of my life we had no PUD power. We really didn't have much that needed power constantly though. As it was quite a ways to work, we simply used a more powerful alternator, and charged a couple extra batteries during the day which provided plenty of power for lights at night. That, plus on weekends or whenever we needed to run something like power tools, we had a generator. Heat was provided by propane, and a wood-stove.

We could, during all of that time, had power hooked up; there was a pole about 500 feet from the house, but it would have cost several thousand dollars, and for that you can buy quite a lot of off-grid stuff.

We weren't really that bad off, it was just that we were able to use very little power compared to most.

Back to my story, a couple years before we moved we got two solar panels, of the amorphous-crystal type. They don't provide quite as much power during clear days, but even when it was cloudy, we were getting full output out of them(Remember, I live in the pacific northwest, where its cloudy like 70% of the time). They produced quite a bit of power and reduced needing to charge up batteries off the truck alternator by quite a bit, although by this point we had a nice propane trailer-furnace which consumed quite a bit of power(those blower motors do take quite bit).

Honestly, if you know how, you don't need all that much power, and heck, even now after a move, we are running on a 30-amp service and perfectly comfortable.

Once you start thinking in terms of needing a lot less power, a lot of these options become way more feasible.

Think about that.

Now, I am not saying that solar panels are going to save the world, but give them credit where credit is due, as they *do* work.


-RobbieThe1st

[Reese Tora]

Of course, if we could just get some powerful heat to electricity conversion device that works at room temperature, all our energy problems would be solved.
At worst, you could take a whole lot of these devices(would be better if they were "active" energy generation, such that they could remove enough heat to lower the surrounding temperature, as then you could turn a few deserts into cold deserts which produce lots of electricity!

There's a little thing called the Second Law of Thermodynamics getting in the way of that idea. Entropy doesn't move in that direction--heat is a waste product of energy production and consumption. Cooling something below the level of its surroundings consumes energy. Just take a look at your electricity bill after running an air conditioner all summer.

Well, I have to disagree with you; Just look at thermocouples. The problem is, they work fine at high temperatures, but you don't get very much at all at room temperatures.
They are working on better ones, but they aren't to that point yet.

-- snip --

-RobbieThe1st

Ah, thermocouples.  They don't work like that; they produce current via a thermal gradient.  IE: one und has to be cooler than the other.

Theoretically, you could use this to reclaim energy from a point heat source (such as an engine or a furnace) by means of a thermopile, but you wouldn't be able to catch energy from uniformly hot environment with them.(in fact, they have been used in this fasion on space craft too far from the sun for solar panels to be effective, according to the wikipedia entry on thermocouples)

[Alondro]

I'm not saying we -should- desalinize water, I'm saying we'd do that before killing each other for sake of "saving the race."

*Charles instructs Jason the telepath what to tell Professor X* Kill the humans... kill all of the humans...   

[Zorro]

I don't think their methodology will work for us, since it involves putting the water/mineral solution in large shallow pools with a  high surface area to volume ratio, and letting the water evaporate.

Like maybe...Eastern California, Arizona, New Mexico, Nevada and Utah?   

[superluser]

Well, I have to disagree with you; Just look at thermocouples. The problem is, they work fine at high temperatures, but you don't get very much at all at room temperatures.
They are working on better ones, but they aren't to that point yet.

Thermocouples won't get you around entropy.

You can turn heat into energy, but it comes at a great cost, and you'll wind up with a net loss of usable energy.

Well, my point was that a central large solar power plant is less efficient than a bunch of house-hold systems, if only because with a house system you can use your roof for it.

I respectfully disagree.  With large central plants, you can use solar thermal energy, which is a heck of a lot more efficient than solar PV (20-55% efficiency vs 12-20% efficiency).

[RobbieThe1st]

Well, I have to disagree with you; Just look at thermocouples. The problem is, they work fine at high temperatures, but you don't get very much at all at room temperatures.
They are working on better ones, but they aren't to that point yet.

Thermocouples won't get you around entropy.

You can turn heat into energy, but it comes at a great cost, and you'll wind up with a net loss of usable energy.

True, if you are using heat which costs you money, like from burning fuel. However, if you  could use ambient heat like the difference in temperature between a slab of sun-warmed metal and the ground, which would work in a lot of cases, or even the great temperature difference between the rocks in an old mine-shaft a long ways down and a few feet under the surface(only problem I see is bringing the differences in temperature close enough to use efficiently).

Well, my point was that a central large solar power plant is less efficient than a bunch of house-hold systems, if only because with a house system you can use your roof for it.

I respectfully disagree.  With large central plants, you can use solar thermal energy, which is a heck of a lot more efficient than solar PV (20-55% efficiency vs 12-20% efficiency).

Hm, how exactly would you turn solar thermal energy into electricity. I can, and do, see it being used for heating water for warming a house/bathwater/whatever, but unless you concentrated it a huge amount, I am not sure how you would get much electricity out, especially using Thermocouples, which, as you said, produces a net loss of energy.

Also, I would think that, depending, you might be able to do the same thing on a smaller scale with house-systems, and then you have much less loss from transmission of the energy.

The main problem with PV systems is that you only are converting a couple of frequencies into electricity. I would think you could get greater efficiency with either multiple layers that convert each one or more frequency, or simply several layers all attuned to one frequency, and then a coating/layer that changes the frequency of incoming light to the frequency needed(not just a colored piece of plastic that simply absorbs any other colors).

An example of this is phosphors, like are used in fluorescent lights, although those phosphors need ultraviolet and while these phosphors could be one component of the stuff, we would need more than just that.


Edit:
Also, according to http://en.wikipedia.org/wiki/Photovoltaic#Power_costs , PV panels, standard ones now have a 25-year warranty and will still be fully functional after 30-40 years. Of course, wind and hydro are even better sources of electricity, with hydro being very efficient and a great way to produce electricity, but that being said, having a roof full of PVs is still a good source of energy, and it looks better than 3-tab roofing which is what most roofs are, around here anyways.

The main problem with solar and wind is you need a large battery bank for times when the wind isn't blowing or the sun isn't shining. The need for a battery bank is lessened with hydro, as you can simply use the water before it goes into your generator as an energy storage device.

With PV, while it may not be the most efficient use of solar-derived energy, its better than simply wasting all of it, like with a roof.

One other thing, is that while you don't get a huge amount of electricity from a roof of PV's, if you don't use electricity for heating, cooking, or running wasteful devices, the cost  per how much you need to run your house is greatly lessened.

For us, even though we, where we are right now have a grid hookup, its only a 30-amp connection, and we don't use much of that.
Our biggest use of electricity is our computers(yes, we do have LCD screens), followed by either the washer/dryer motor(though, those aren't on very long time-wise, and the dryer is a propane dryer), or lighting(98% of all our lighting is fluorescent).

I do admit I am getting a bit off topic here, but the point I am trying to make is that if you  cut down on the amount of electricity you need to use, things that weren't practical before suddenly become much more practical.


PVs as well as wind generators become less costly as things are done cheaply in china(although, the quality of work suffers, and im not saying its a good idea), and once large super-capacitors become cheap enough, it will be easy for people to be completely off-grid, which means less power needs to be generated via conventional means, like oil plants, and who knows how many more years the uranium supply would last.

Also, if the regulations were less, and more dams like the Grand Coulee dam were built, a lot of this would be moot, as that one dam generates a massive amount of energy, which does not need to be made using other means.

I seem to be rambling and not making a huge amount of sense, but try to understand the various, sometimes contradictory, points I am making.


-RobbieThe1st

[superluser]

Hm, how exactly would you turn solar thermal energy into electricity. I can, and do, see it being used for heating water for warming a house/bathwater/whatever, but unless you concentrated it a huge amount, I am not sure how you would get much electricity out, especially using Thermocouples, which, as you said, produces a net loss of energy.

I'm talking about SEGS.

[Reese Tora]

I don't think their methodology will work for us, since it involves putting the water/mineral solution in large shallow pools with a  high surface area to volume ratio, and letting the water evaporate.

Like maybe...Eastern California, Arizona, New Mexico, Nevada and Utah?   

Well, my point was that you lose the water to the atmosphere with thier methodology.  You could go around and build a large building over the ponds to condense the water and capture it.

Now, desalination can provide a good deal of water in general...

Report regarding water use and conservation in a city local to me:

http://www.ci.huntington-beach.ca.us/files/users/planning/EIR%2000-02%20attachment3.pdf

[RobbieThe1st]

Hm, how exactly would you turn solar thermal energy into electricity. I can, and do, see it being used for heating water for warming a house/bathwater/whatever, but unless you concentrated it a huge amount, I am not sure how you would get much electricity out, especially using Thermocouples, which, as you said, produces a net loss of energy.

I'm talking about SEGS.

This could be scaled down.

Speaking of something like this, a few years ago, at a RE fair, I saw an interesting device. This device had a parabolic dish, and at the focal-point of the dish a carbon(I believe) rod. The rod would get extremely hot, and it seems it would cause air to expand, driving this tiny little engine. Basically, this device was a solar-heat powered engine. The only problem was it needed concentrated heat and if a cloud went over, it wouldnt work too well at all. Also, it didn't provide much torque, though compared to the size of the engine, I am not sure how much torque it provided. The engine was a bit larger than my hand, and I could stop the little output flywheel with my hand easily. It was also a bit noisy, which is why I never mentioned it before.

[superluser]

I'm talking about SEGS.

This could be scaled down.

I suspect that you'd lose quite a bit of efficiency.

Speaking of something like this, a few years ago, at a RE fair, I saw an interesting device.

[...description snipped...]

That sounds like a Stirling Engine, which is indeed going to be the future of solar thermal energy.  I just don't know if that's going to be the energy source of the future.

[Tezkat]

Show me a resource that isn't scarce by economic definitions (it commands a price by having a limited supply at one time) and I shall declare you god.

Stupidity? There's a seemingly endless, renewable supply that can be tapped to cause capital to flow in the direction of smart people.

Seriously, though... until we mange to pollute it beyond unfiltered usability, air still respresents a very important non-scarce resource. Sunlight is potentially non-scarce as well, though making use of it may currently be limited by other factors (e.g. costs of land and manufacturing).

And all resources being scarce is hardly an excuse to deplete the ones that would ordinarily have been renewable.

True, if you are using heat which costs you money, like from burning fuel. However, if you  could use ambient heat like the difference in temperature between a slab of sun-warmed metal and the ground, which would work in a lot of cases, or even the great temperature difference between the rocks in an old mine-shaft a long ways down and a few feet under the surface(only problem I see is bringing the differences in temperature close enough to use efficiently).

Reese and superluser already addressed it, but since you seem to have misunderstood somewhat: Basically, you can't harness "ambient" heat for positive energy production. Any system will have a net loss of usable heat. It's a fundamental law of physics. It's not the thermocouples that create net losses. They'd merely serve a recyclers of heat waste rather than a primary source of energy. The relatively "free" sources of heat (solar, geothermal) can be tapped more easily through other means (typically using mechanical energy as an intermediary for power generation).

Hm, how exactly would you turn solar thermal energy into electricity. I can, and do, see it being used for heating water for warming a house/bathwater/whatever, but unless you concentrated it a huge amount, I am not sure how you would get much electricity out, especially using Thermocouples, which, as you said, produces a net loss of energy.

Also, I would think that, depending, you might be able to do the same thing on a smaller scale with house-systems, and then you have much less loss from transmission of the energy.

You're grossly overestimating the transmission losses from an electrical grid, which are usually on the order of only a few percent of the original output unless the destination is quite far from the generation plant (which, admittedly, it sometimes is, but average transmission losses typcally fall between 1% and 10%). In terms of efficiency metrics, central power generation usually wins out. For instance, using the solar thermal plants that superluser mentioned (rather than PV) requires bulky thermal power generators you probably wouldn't want in your backyard (and would also be much less efficient than those in a larger facility), but the cost savings of using a larger, more efficient power plant more than offset the small losses in transmission.

Given the density of our major population centers, energy distribution is not a serious problem at the moment. In fact, increased population density increases the overall efficiency of energy use, but it also greatly reduces the power density per individual for something like plastering one's home with solar panels, making gridless living much less attractive.

I'm not knocking solar power, per se. Ultimately, most forms of energy on earth constitute solar power with varying degrees of processing along the way. Solar thermal power currently costs about as much to generate as wind power, although it suffers from similar issues regarding geography and variability. Both of those emission-free power sources cost about twice as much per kWh as the modern nuclear plants Alondro mentioned, which in turn costs about twice as much as burning fossil fuels. (Hydroelectric usually falls somewhere between the last two, but it's obviously very geography dependent.) Solar panels, by contrast, cost more than any of those, and their manufacturing is often not all that eco-friendly. Sure, developing self-assembling carbon-based solar collectors to spread over rooftops and road networks could conceivably make all of our energy problems go away, but we're still a ways off from making that feasible.

(And before the smartasses chime in... Yes, there are already "self-assembling carbon-based solar collectors" spread all over our agricultural land. Y'all know that's not what I'm talking about, right? )

I don't think their methodology will work for us, since it involves putting the water/mineral solution in large shallow pools with a  high surface area to volume ratio, and letting the water evaporate.

Like maybe...Eastern California, Arizona, New Mexico, Nevada and Utah?   

Well, my point was that you lose the water to the atmosphere with thier methodology.  You could go around and build a large building over the ponds to condense the water and capture it.

Now, desalination can provide a good deal of water in general...

Huh?

Modern desalination plants use a method more along the lines of high pressure filtration than evaporation. Even those that still rely on (more expensive) thermal methods employ systems slightly more complicated than evaporating giant pools of water...

[Reese Tora]

Well, my point was that you lose the water to the atmosphere with thier methodology.  You could go around and build a large building over the ponds to condense the water and capture it.

Now, desalination can provide a good deal of water in general...

Huh?

Modern desalination plants use a method more along the lines of high pressure filtration than evaporation. Even those that still rely on (more expensive) thermal methods employ systems slightly more complicated than evaporating giant pools of water...

Addressing the techniques by which the Israel extract minerals and salts from the dead sea, which was brought up earlier in the thread by Valynth as something which could be converted for desalination purposes. (Atleast, that was my impression of why he brought it up.)

[RobbieThe1st]

Show me a resource that isn't scarce by economic definitions (it commands a price by having a limited supply at one time) and I shall declare you god.

Stupidity? There's a seemingly endless, renewable supply that can be tapped to cause capital to flow in the direction of smart people.

Seriously, though... until we mange to pollute it beyond unfiltered usability, air still respresents a very important non-scarce resource. Sunlight is potentially non-scarce as well, though making use of it may currently be limited by other factors (e.g. costs of land and manufacturing).

And all resources being scarce is hardly an excuse to deplete the ones that would ordinarily have been renewable.

True, if you are using heat which costs you money, like from burning fuel. However, if you  could use ambient heat like the difference in temperature between a slab of sun-warmed metal and the ground, which would work in a lot of cases, or even the great temperature difference between the rocks in an old mine-shaft a long ways down and a few feet under the surface(only problem I see is bringing the differences in temperature close enough to use efficiently).

Reese and superluser already addressed it, but since you seem to have misunderstood somewhat: Basically, you can't harness "ambient" heat for positive energy production. Any system will have a net loss of usable heat. It's a fundamental law of physics. It's not the thermocouples that create net losses. They'd merely serve a recyclers of heat waste rather than a primary source of energy. The relatively "free" sources of heat (solar, geothermal) can be tapped more easily through other means (typically using mechanical energy as an intermediary for power generation).

I think you misunderstand. By ambiant heat, I mean the heat that is in the air, indirectly added by the sun. The atmosphere(and ground/water) is a gigantic energy storage device of solar and some earth-core-heat, which we can tap(although quite a bit is getting radiated off into space). Yes, if you are attempting to draw heat out of a closed source, just like a battery, it will eventually run out of energy, however in this case, the energy is being replenished every day(literally!), and, as in most places the air doesn't freeze during most of the year, you can still draw energy out.

And, in this case, the energy is "free" as in it doesn't cost us anything to replenish(thanks to the sun), which means that even at low efficiency, its still a good tap-able resource.

Hm, how exactly would you turn solar thermal energy into electricity. I can, and do, see it being used for heating water for warming a house/bathwater/whatever, but unless you concentrated it a huge amount, I am not sure how you would get much electricity out, especially using Thermocouples, which, as you said, produces a net loss of energy.

Also, I would think that, depending, you might be able to do the same thing on a smaller scale with house-systems, and then you have much less loss from transmission of the energy.

You're grossly overestimating the transmission losses from an electrical grid, which are usually on the order of only a few percent of the original output unless the destination is quite far from the generation plant (which, admittedly, it sometimes is, but average transmission losses typcally fall between 1% and 10%). In terms of efficiency metrics, central power generation usually wins out. For instance, using the solar thermal plants that superluser mentioned (rather than PV) requires bulky thermal power generators you probably wouldn't want in your backyard (and would also be much less efficient than those in a larger facility), but the cost savings of using a larger, more efficient power plant more than offset the small losses in transmission.

Given the density of our major population centers, energy distribution is not a serious problem at the moment. In fact, increased population density increases the overall efficiency of energy use, but it also greatly reduces the power density per individual for something like plastering one's home with solar panels, making gridless living much less attractive.

I'm not knocking solar power, per se. Ultimately, most forms of energy on earth constitute solar power with varying degrees of processing along the way. Solar thermal power currently costs about as much to generate as wind power, although it suffers from similar issues regarding geography and variability. Both of those emission-free power sources cost about twice as much per kWh as the modern nuclear plants Alondro mentioned, which in turn costs about twice as much as burning fossil fuels. (Hydroelectric usually falls somewhere between the last two, but it's obviously very geography dependent.) Solar panels, by contrast, cost more than any of those, and their manufacturing is often not all that eco-friendly. Sure, developing self-assembling carbon-based solar collectors to spread over rooftops and road networks could conceivably make all of our energy problems go away, but we're still a ways off from making that feasible.

(And before the smartasses chime in... Yes, there are already "self-assembling carbon-based solar collectors" spread all over our agricultural land. Y'all know that's not what I'm talking about, right? )

True, although its not nearly as good in the suburbs/country, so I would think that you would have a couple big plants for the citys, and for the country, most people being gridless.

Also, although creating PV's isnt harmless to the environment, being that they will last for 30+ years, and, according to wikipedia they are working on ways of recycling them after they fail, which may shift the calculation a bit.


-RobbieThe1st

[Tezkat]

Addressing the techniques by which the Israel extract minerals and salts from the dead sea, which was brought up earlier in the thread by Valynth as something which could be converted for desalination purposes. (Atleast, that was my impression of why he brought it up.)

Oh, heh... That's more a way of collecting the salt than the water.

I think you misunderstand. By ambiant heat, I mean the heat that is in the air, indirectly added by the sun. The atmosphere(and ground/water) is a gigantic energy storage device of solar and some earth-core-heat, which we can tap(although quite a bit is getting radiated off into space). Yes, if you are attempting to draw heat out of a closed source, just like a battery, it will eventually run out of energy, however in this case, the energy is being replenished every day(literally!), and, as in most places the air doesn't freeze during most of the year, you can still draw energy out.

And, in this case, the energy is "free" as in it doesn't cost us anything to replenish(thanks to the sun), which means that even at low efficiency, its still a good tap-able resource.

Thermocouples are still grossly less efficient (both in terms of manufacturing costs and power density relative to surface area) than other solar collection technologies. I'm not aware of any serious efforts to deploy them as a large scale power generation systems...

True, although its not nearly as good in the suburbs/country, so I would think that you would have a couple big plants for the citys, and for the country, most people being gridless.

Well... rural populations do tend more towards self-sufficiency due to lower population densities. While gridless homes out in the middle of nowhere would certainly be expected, I'm not convinced that we're headed towards a gridless countryside. Agriculture, for instance, consumes a tremendous amount of energy (for irrigation, machinery, etc.). In the absence of fossil fuel sources, economies of scale might still point towards local power plants serving the surrounding area. Not to mention that land for solar power generation would compete directly with agricultural use unless said farmers' properties included a lot of otherwise unused, non-arable land.

[RobbieThe1st]

Addressing the techniques by which the Israel extract minerals and salts from the dead sea, which was brought up earlier in the thread by Valynth as something which could be converted for desalination purposes. (Atleast, that was my impression of why he brought it up.)

Oh, heh... That's more a way of collecting the salt than the water.

I think you misunderstand. By ambiant heat, I mean the heat that is in the air, indirectly added by the sun. The atmosphere(and ground/water) is a gigantic energy storage device of solar and some earth-core-heat, which we can tap(although quite a bit is getting radiated off into space). Yes, if you are attempting to draw heat out of a closed source, just like a battery, it will eventually run out of energy, however in this case, the energy is being replenished every day(literally!), and, as in most places the air doesn't freeze during most of the year, you can still draw energy out.

And, in this case, the energy is "free" as in it doesn't cost us anything to replenish(thanks to the sun), which means that even at low efficiency, its still a good tap-able resource.

Thermocouples are still grossly less efficient (both in terms of manufacturing costs and power density relative to surface area) than other solar collection technologies. I'm not aware of any serious efforts to deploy them as a large scale power generation systems...

Yes, that I know, and one main reason is they don't work well with low temperatures. One of the universities is trying to rectify that problem though.

Well, if you got the temperatures down to being able to get a reasonable amount of electricity out of only a few degrees temperature difference, then you could use them in combination with other technologies, for example you stick a layer of Thermocouples on the back of a PV panel, to both generate more heat and to cool the PV.

True, although its not nearly as good in the suburbs/country, so I would think that you would have a couple big plants for the citys, and for the country, most people being gridless.

Well... rural populations do tend more towards self-sufficiency due to lower population densities. While gridless homes out in the middle of nowhere would certainly be expected, I'm not convinced that we're headed towards a gridless countryside. Agriculture, for instance, consumes a tremendous amount of energy (for irrigation, machinery, etc.). In the absence of fossil fuel sources, economies of scale might still point towards local power plants serving the surrounding area. Not to mention that land for solar power generation would compete directly with agricultural use unless said farmers' properties included a lot of otherwise unused, non-arable land.

Well, true, however I seriously doubt most farms could cope without some sort of liquid fuel for power, no matter how cheap electricity is, its the difference in energy density.
However, having a farm that has solar/wind/micro-hydro for lights, water pumping, and, if there is a farmhouse there, for any house-related electrical needs, and then running tractors and other equipment on some sort of fuel, be it algae based or who-knows-what based, is cirtainly feasible.


Hm, also, for large slow-moving equipment, you could also use steam, and run the boiler on dried grass, wood, coal, or whatever is convenient. It would also be reasonably easy, as you could simply waste the used steam like they did on trains, as it would be easy to fill up with water whenever needed.


-RobbieThe1st

[Alondro]

Storage of electricity might have a solution, depending on how credible this one company is that claims to have an ultracapacitor in development.  I dunno if I buy it.  There's very little known about that company, not even a website, and it may just be a fraud.

If it comes out on the market and works, then I'll believe it.

[gh0st]

hey what if we take those super capacitors and hook like 10 of them up to the lightning rod on the empire state building... it alone gets zapped more than 300 times a year so shouldn't it produce enough electricity to power it and a few buildings around it? and if it works then we could just put that in every sky scraper from here to Tokyo. and as an added bonus we could deck the sides with solar panels and put up retractable wind mills if you need more then we could always set up a few metal things that collect heat which turns water into steam which will move a turbine it's like the ultimate in green fuels.

that or search into plasma reactors it's really easy to make plasma you do it practically every time you put metal in a microwave.

[RobbieThe1st]

hey what if we take those super capacitors and hook like 10 of them up to the lightning rod on the empire state building... it alone gets zapped more than 300 times a year so shouldn't it produce enough electricity to power it and a few buildings around it? and if it works then we could just put that in every sky scraper from here to Tokyo. and as an added bonus we could deck the sides with solar panels and put up retractable wind mills if you need more then we could always set up a few metal things that collect heat which turns water into steam which will move a turbine it's like the ultimate in green fuels.

that or search into plasma reactors it's really easy to make plasma you do it practically every time you put metal in a microwave.

Also, you get glow plasma when you first start a fluorescent light.

-RobbieThe1st

[Kuari]

What we need to start off with is someone raid all the documents oil companies keep secret and release them to the public.  If no answers are found there...  YA MULE!!!  YA!!!  Back to good ol' horses once the oil runs out.