which is the carrying capacity of the earth?

[Suicidesoldier#1]

Je Nique vos Merdiers

Suicidesoldier#1

When you have half the population density of fargo north dakota all over the earth, and calculate how much farmland is needed, how much available arable land is available, and whatnot, and how much you could produce with the amount of water and fertilizer in the world, and including ranchland and cows n stuff, you get about oh 60 billion or so.

Metabolic efficiency is lower at low population densities, sprawl is bad for ecosystem health, and so is monoculture farming. You are never going to support 60B people on a Western diet with geoponic monocultures, we are already destroying the ecosystem with less than 10% of that population acting in the way you've described.

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With recycling and the awesome size of the earth there's not much of a problem with natural resources like iron and silicon.

It depends how often you are recycling them. There is such a thing as "entropy" for materials, they cannot be recycled infinitely.

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Since energy can be alleviated with Thorium, and in the future hopefully graphene solar panels, we'll be fine.

Uh, I think you have that a little backwards. Solar energy is what we can do now. Thorium is not. We already have the facilities to produce high-efficiency CIGS cells, and some people I know at a Dutch hackerspace called Labitat are building a 3D printer-like device that can produce CIGS cells with powder metallurgy in a small workshop. It's feasible that it could even produce the latest development in solar tech, which is a micropatterned metal screen on the surface of the panel that reduces its reflectivity by 're-capturing' light.

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Energy is your biggest concern since resources are abundant and what we need is transformation, say into cars or ammonia, instead of say, nitrogen and oxygen.

Not true. Solar energy will eventually reach a point where there is a surplus of energy for most of the day, with capacity only being reached at a modal or bimodal time each day. That surplus energy is going to have to be stored or used, or else it's going to waste. And since it's already falling from the sky, there is no reason not to store or use it, because the other possibilities for it are producing heat or being metabolized by autotrophs. At that point, we have a few choices:
1. Use the stored energy to gradually reduce the amount of solar energy captured
2. Build increasing amounts of storage and have ever-larger amounts of reserve energy
3. Use the excess generated energy for an "idle process", to do things like recycling, refining, computation, or scientific research.

Energy seems like it's scarce because fossil fuels are scarce. Fossil fuels are based on the same energy source as photovoltaic technology, which is the sun. But fossil fuels have a much lower conversion efficiency than PV, a very low replenishment rate, and by using them we are gradually reducing the effectiveness of all other forms of energy including fossil energy itself. The faster you extract and use it, the lower its efficiency.
Thorium has similar problems, except that it is created by thermonuclear processes that only occur near the end of a star's life, so it has an even lower replenishment rate than fossil fuels. It is a high-quality energy now, but anyone who studies energy, economics, or anything of the like knows that under the existing social paradigm, higher extraction efficiency (in this case, extraction of energy from the ground) just leads to higher consumption. Thus, the most likely outcome, if we switch the thorium energy, is that the economy will continue to be based on money flows decoupled from most observable measurements, and energy use will increase until thorium becomes a low-quality energy. Then, the people of the future will be having the exact same discussion we are having now, which is that solar energy will never be as efficient as thorium.

In reality, it's materials that are scarce, at least while we're confined to this planet. Energy falls on our heads daily, and will continue to do so for billions of years. Materials take billions of years to create, and cannot be recycled infinitely. Building long-lasting physical products that can be divided into small/standardized modules so their design can evolve over time, as opposed to being replaced completely, should be a very high priority for civilization, after the switch to ecologically/economically sustainable energy/agricultural technologies.

Graphene is somewhere around 40,000 dollars per pound. Most of that is in energy costs. By reducing energy costs, we can produce graphene cheaply, which would allow us to say, coat the poles of the earth in graphene solar panels, and get enormous amounts of electricity.

But that's not possible until we have cheap graphene solar panels. As far as "3-D printers" go, it's really not that amazing of technology. You can say, make a 3-D plastic mold from a computer model; they've been doing this for quite some time.


But producing graphene still present a great deal of difficulty due to it's costs. The best, highest quality methods require craploads of electricity.

Thorium, also is available. There are already small reactors and liquid salt designs available. All you would have to do is scale it up. Since uranium already powers 20.9% of the U.S.'s electricity with 104 reactors, and thorium could be just as powerful, up to 200 times more powerful, and there's no chance of a melt down, it's relatively safe etc. there aren't many issues.


As far as the earth can never support 60 billion people?

Perhaps ironically, you're already suggesting we can produce an infinite amount of energy from solar panels, right now?!?! So if that's true, we can feed enormous amounts of people. With aquaponics, we can grow fish and crops without fertilizer and without producing nitrate rich polluting water (the fish waste feeds the plant, the plants clean the fish water). Since fish food can be made from spirulina, which basically can grow in water and with sunlight, you can have an ultra efficient process that doesn't require fertilizer at all, that is traditional fertilizer. So with a bunch of properly designed greenhouses, and with enough energy, we can feed however many people we want.


As far as being a moron and using a less efficient method because you're afraid people will actually benefit from it?

There's always ways to increase the cost arbitrarily if people go over their limit or use too much, or just increase it arbitrarily with say, a tax. Using a less efficient design when power can be scarce is a very silly thing to do. Considering that 90% of electricity goes to industry and business, I'm not sure raising the price for your average person would really help much.

[Suicidesoldier#1]

Llorin

Suicidesoldier#1

Since energy can be alleviated with Thorium, and in the future hopefully graphene solar panels

SO YEAH!

What are graphene solar panels?

I just know Silicon Borium panels with a 19% of efficiency and Gallium Arsenic Indium panels with a 29% of efficiency.

Graphene solar cells!

It's not an in depth source but it is a basic one; essentially, it's just graphene designed to absorb light energy.

Graphene has a number of good qualities, being flexible, around 200 times stronger than steel, resistant to corrosion, erosion, and most other forms of destruction, and could potentially be around 60% efficient, for the high quality graphene.

Part of the problem is the energy utilized in creating them.


Since they're so durable, in the long term, say thousands of years, their output would be massive, so they would be a good source of power for the next billion years or so.

But as of now, they're too expensive to make and they're energy intensive.


Perhaps ironically, if we found a cheap power source, we could make a crapload of graphene solar cells.

The advantage would be that long term, fuel less million year power would be available, but that it would be an expensive downpayment.


Which is why it's best reserved for slow production over a long time and then. probably coating the poles.

Another useful aspect of graphene is it's potential to serve as a battery. Potentially storing way more than lithium ion, it would make both a lightweight and small battery, meaning you could literally just lay down flexible, nigh indestructible squares on your roof and have tons of power. Or you could have a giant blanket, so to speak, in Antartica, that wouldn't need batteries, would be operating in high sunlight conditions with low temperatures, all good for solar cells, which is an ideal place to have them.


Silicon solar panels would particularly benefit from this.

But without first having great leaps in efficiency, or reducing electricity costs in general, it's not that easy of an option. But over the next 1000 years it may be possible, and since even the best fuels will only last a few hundred thousand to million years, fuel less energy will essentially be the way to go, with energy being used to make said panels, rather than power things, directly. That would give us the greatest long term energy solution for millions of years, but we're not exactly ready to do that, now. xp

[Je Nique vos Merdiers]

Suicidesoldier#1

Graphene is somewhere around 40,000 dollars per pound. Most of that is in energy costs.

That's weird, I could make a pound of graphene electrodes for about $25k at per-gram (of graphite oxide) prices. What process are you referring to? What form factor? If I could perform MHM myself, I could probably reduce my GO price to <$80/g

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By reducing energy costs, we can produce graphene cheaply, which would allow us to say, coat the poles of the earth in graphene solar panels, and get enormous amounts of electricity.

Coating the poles of the Earth with graphene solar panels would be a bad idea, it would severely increase its albedo, probably melting the ice caps, and you'd only have a 50% duty cycle since the Earth is tilted. Solar energy is most appropriate near the equator, preferrably in desert areas (though there are concerns that it destroys the habitat of desert turtles). Graphene is totally not a necessity for solar energy to be workable, and graphene certainly has a magic allure to it that makes its properties overblown.

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As far as "3-D printers" go, it's really not that amazing of technology. You can say, make a 3-D plastic mold from a computer model; they've been doing this for quite some time.

I know how 3D printing works, I have a Prusa i2 in my living room. What I'm talking about is not plastic printing, it's powder-based electron beam melting (EBM), which is capable of producing full-strength, finished alloy parts with extremely high tolerances and no voids. As I already mentioned, it is capable of producing cadmium gallium selenide solar cells, and will probably also be able to produce micropatterned gold/silver screens to increase the absorption of the panel. Rapatan and his team already have a design for a power source, and are working on the vacuum chamber and electron gun. After that, they need to design a turbomolecular pump for roughing, and atm it seems they are going to use a titanium filament getter pump for high vacuum. Once the prototype is created, it should be able to replicate itself exponentially, as an EBM machine would be able to make ALL of its own parts, not just low-precision joints, gears and bushings.

And if you think 3D printing is not amazing, you are missing the point. It's not just 3D printing that's awesome, it's that open-source hardware has enabled anyone with more or less a high-school education to source and build one for less than $1000. In fact, they're getting to be <$500 at this point, which is a 20-fold cost reduction over the cheapest proprietary models. Not only that, but you can download open designs to plug in to your printer and manufacture. I can make a knob for my roommate's van, at roughly the same price as an OEM knob, without having to leave my house or wait for delivery.

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Thorium, also is available. There are already small reactors and liquid salt designs available. All you would have to do is scale it up.

"All you would have to do is scale it up" is a rather silly thing to say if you know anything about technology. Scaling is not just making things bigger, you run into problems like heat, surface area:volume ratios, etc.

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Since uranium already powers 20.9% of the U.S.'s electricity with 104 reactors, and thorium could be just as powerful, up to 200 times more powerful, and there's no chance of a melt down, it's relatively safe etc. there aren't many issues.

Except that thorium is still a fuel that we have to dig out of the Earth, which means its quality will decrease over time, and we do not have an unlimited supply. As far as humans go, solar energy is basically unlimited.

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Perhaps ironically, you're already suggesting we can produce an infinite amount of energy from solar panels, right now?!?!

Did you even read what I wrote? I'm suggesting that the amount of energy we can produce from solar panels is such that we will have an energy surplus for almost the entire day.

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As far as being a moron and using a less efficient method because you're afraid people will actually benefit from it?

There's always ways to increase the cost arbitrarily if people go over their limit or use too much, or just increase it arbitrarily with say, a tax. Using a less efficient design when power can be scarce is a very silly thing to do. Considering that 90% of electricity goes to industry and business, I'm not sure raising the price for your average person would really help much.

What are you talking about? I never called you a moron, and the rest of that section sounds like nothing I have ever said/implied.

[Je Nique vos Merdiers]

Suicidesoldier#1

Graphene solar cells!

It's not an in depth source but it is a basic one; essentially, it's just graphene designed to absorb light energy.

Since they're talking about transparent graphene films being integrated into organic PV cells, I'm pretty sure that that's actually talking about using graphene as an electrode, not a P-N junction.

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Another useful aspect of graphene is it's potential to serve as a battery. Potentially storing way more than lithium ion, it would make both a lightweight and small battery, meaning you could literally just lay down flexible, nigh indestructible squares on your roof and have tons of power. Or you could have a giant blanket, so to speak, in Antartica, that wouldn't need batteries, would be operating in high sunlight conditions with low temperatures, all good for solar cells, which is an ideal place to have them.

Graphene isn't magic. Again, you are making the mistake of assuming that graphene in batteries = graphene batteries. Current technology, as far as I know, is capable of producing Lithium ion batteries with graphene electrodes. Even more promising is using those electrodes for electrolytic double-layer capacitors (EDLCs, also known as "supercapacitors" wink . They have a high energy density, faster charge/discharge rate, and keep their capacity for many more charge/discharge cycles than batteries, while being safer. As far as actual batteries go, the best technology thus far seems to be molten salt batteries, which are being made to operate at increasingly lower temperatures, and have energy densities that rival LiFePo.

[Suicidesoldier#1]

Je Nique vos Merdiers

Suicidesoldier#1

Graphene solar cells!

It's not an in depth source but it is a basic one; essentially, it's just graphene designed to absorb light energy.

Since they're talking about transparent graphene films being integrated into organic PV cells, I'm pretty sure that that's actually talking about using graphene as an electrode, not a P-N junction.

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Another useful aspect of graphene is it's potential to serve as a battery. Potentially storing way more than lithium ion, it would make both a lightweight and small battery, meaning you could literally just lay down flexible, nigh indestructible squares on your roof and have tons of power. Or you could have a giant blanket, so to speak, in Antartica, that wouldn't need batteries, would be operating in high sunlight conditions with low temperatures, all good for solar cells, which is an ideal place to have them.

Graphene isn't magic. Again, you are making the mistake of assuming that graphene in batteries = graphene batteries. Current technology, as far as I know, is capable of producing Lithium ion batteries with graphene electrodes. Even more promising is using those electrodes for electrolytic double-layer capacitors (EDLCs, also known as "supercapacitors" wink . They have a high energy density, faster charge/discharge rate, and keep their capacity for many more charge/discharge cycles than batteries, while being safer. As far as actual batteries go, the best technology thus far seems to be molten salt batteries, which are being made to operate at increasingly lower temperatures, and have energy densities that rival LiFePo.

Multiple layers of graphene, some conductive, some not conductive, would serve as super awesome capacitors, like in the capacitors you're talking about; except that graphene sheets could be stacked and only be an atom wide.

With an insulating layer, which graphene can be super insulating, and with a super conductive layer, you could have a super capacitor with thousands of times the current capacitance as current super capacitors, and since it can hold on to it's charge better, at around 5-10% of it's maximum, for months on end, it could serve as a battery by storing power over long periods of time, which most capacitors lose their energy relatively quickly.


In comparison, at 1% of it's total capacitance a graphene super capacitor could store at least 10 times more than a current lithium ion battery, but since it could last for millions of cycles, instead of thousands, wouldn't be as sensitive to heat and the environment, and since it's a capacitor, so it could dump out all it's power in an incredibly short time frame without burning itself out, it would make an excellent replacement for lithium ion batteries.

Graphene isn't magic, but it's extremely powerful. At 200 times the strength of steel, and being 1/10th the weight, it is 2000 times the strength of steel in terms of weight, instead of say kevlar, at 5 times the strength of steel on a weight to weight basis. Due to it's incredibly high durability, it could last WAY longer than current batteries and store potentially hundreds of times the electricity. They've already created square meters of it, but it's something like 30-100 dollars per square centimeter. It's expensive, but most of it's cost rests in electricity; reduce that, you reduce the problems with graphene, which is mostly cost.


High quality graphene has a lot of potential applications; it depends on the type, shape, and quality.

If produced correctly it can do a lot of things, which is what makes nanotechnology, in general, so promising.


As far as thorium is concerned, the molten salt reactors really are fairly easy to scale. Reduced surface area to volume ratio means that the pressure is less. This means it would be easier to work with and generally safer; you also could, theoretically, just have more piping. More piping = more molten salt = same size with no change.

Since it has like 200 times the heat capacity of water, in relation to expansion, and therefore pressure, it would be a lot safer. Since the basic process really only calls for more thorium and fuel, or say, making more reactors, no, it's not that hard to scale it up to full scale country wide production. So it's kind of silly when you say it isn't easily scalable. That's like saying you could make more coal plants. Or a bigger one. O_o


Wait, melting the ice caps with solar panels on them?

lol okay. You realize the ice caps would absorb less energy, since the solar panels would be absorbing them, so if anything, it would slow down the melting of the ice caps? O_o


But how about I just go out on a limb here.

Where do you plan on getting the energy for making all these solar panels in the first place; at some level, you need start up energy before you can make solar panels, since it requires energy to produce them. xp

[Je Nique vos Merdiers]

Suicidesoldier#1

Multiple layers of graphene, some conductive, some not conductive, would serve as super awesome capacitors, like in the capacitors you're talking about; except that graphene sheets could be stacked and only be an atom wide.

I'm talking about electrolytic capacitors, and since the only substance known to pass through graphene in the normal dimension is H2O, stacked layers of graphene would produce deionized water. Using graphene as an insulator requires a bilayer of graphene, and if I'm reading the study correctly, the insulating property is destroyed by electric fields in the normal direction, or in other words, where your current is supposed to go in the cap. It's also susceptible to magnetic fields, which means it's probably not going to be a terribly robust insulator.

ELDCs also require a dialectric, not an insulator. The design is electrode|electrolyte|dialectric|electrolyte|electrode.

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In comparison, at 1% of it's total capacitance a graphene super capacitor could store at least 10 times more than a current lithium ion battery,

What are you talking about? ELDCs have differing levels of capacitance depending on their design. So far there are no designs for ELDCs with an energy/mass density that rivals Lithium batteries, and by the way, as I already mentioned, the fancy graphene designs you're talking about can just as easily be applied to the electrodes of a Lithium battery.

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Graphene isn't magic, but it's extremely powerful. At 200 times the strength of steel, and being 1/10th the weight, it is 2000 times the strength of steel in terms of weight, instead of say kevlar, at 5 times the strength of steel on a weight to weight basis. Due to it's incredibly high durability, it could last WAY longer than current batteries and store potentially hundreds of times the electricity.

It sounds like you haven't read much about how batteries actually work. The reason that batteries lose capacity is because the "holes" that store ions get clogged up over time, by sulfite ions, IIRC. The lifespan of a battery has nothing to do with any mechanical property of the materials that make it up. It does have to do with the surface area available to accept ions, which also affects its charge/discharge rate.

You should probably read journal articles about the technologies you're touting, rather than telling me things about them that are largely incorrect/nonsensical. I'm not trying to be a d**k, but I've read lots and lots about all this stuff and it doesn't sound like you've read much beyond crappily-written news articles.

[Je Nique vos Merdiers]

I've been reading a very good blog from Professor Tom Murphy at UCSD, who points out that assuming a continuing 2.5% annual growth rate, as people/economists like to delude themselves into believing will continue indefinitely, applying the second law of thermodynamics means that in 400 years, the generated energy would radiate enough heat to bring the Earth's surface to boiling temperatures. In 1700 years, we will require the Sun to be surrounded by a 100% efficient photovoltaic sphere.

[Llorin]

Je Nique vos Merdiers

I've been reading a very good blog from Professor Tom Murphy at UCSD, who points out that assuming a continuing 2.5% annual growth rate, as people/economists like to delude themselves into believing will continue indefinitely, applying the second law of thermodynamics means that in 400 years, the generated energy would radiate enough heat to bring the Earth's surface to boiling temperatures. In 1700 years, we will require the Sun to be surrounded by a 100% efficient photovoltaic sphere.

Therefore energy is not the final answer.

[Vanya Cellest]

you all seem to be talking about energy but have you considered the waste?

i've been told the carrying capacity of the world is roughly about 10 billion and part of that has to do with pollution. Even if you had infinite energy and food we would still begin to pollute ourselves to death...

So if you wanted a higher carrying capacity, you'd have to 1st address the issue of the amount of pollution/garbage/toxins.

Farming would have to become more efficient and NOT reliant on fossil fuels as it currently is. Things like how we eat would have to be changed as well. Uh, what i'm saying i guess is all that complex energy stuff you guys are talking about is only part of the issue.

Don't jump my bones or anything i was just trying to leave a useful comment. >.< It's an interesting topic.

[Llorin]

Let's limit the area because to make it little easier. Is it possible to know the carrying capacity of a country knowing its characteristics ?

[God Emperor Baldur]

I think Bill Nye said it's 40 billion assuming everyone has bare necessities with barely sufficient nutrition.

[Llorin]

Lord Akhenaton

I think Bill Nye said it's 40 billion assuming everyone has bare necessities with barely sufficient nutrition.

I just wonder... why?

Wikipedia and all kind of experts point out a number or a range between a lower limit and upper one ... how do they get this numbers?

There has not been any calculus to get these numbers.

[God Emperor Baldur]

Llorin

Lord Akhenaton

I think Bill Nye said it's 40 billion assuming everyone has bare necessities with barely sufficient nutrition.

I just wonder... why?

Wikipedia and all kind of experts point out a number or a range between a lower limit and upper one ... how do they get this numbers?

There has not been any calculus to get these numbers.

Talk to the science guy because I do not have the answers. But the the biggest correlation that population has is food. Yes healthcare helps with that, but healthcare simply allows more people. Food is people's limit. No food, no life.

[Llorin]

Lord Akhenaton

Llorin

Lord Akhenaton

I think Bill Nye said it's 40 billion assuming everyone has bare necessities with barely sufficient nutrition.

I just wonder... why?

Wikipedia and all kind of experts point out a number or a range between a lower limit and upper one ... how do they get this numbers?

There has not been any calculus to get these numbers.

Talk to the science guy because I do not have the answers. But the the biggest correlation that population has is food. Yes healthcare helps with that, but healthcare simply allows more people. Food is people's limit. No food, no life.

Thank you... I will ask it to him.
I personally believe it is extremely complex issue. I guess no one can know it without using complex models and computer simulation... and even then there can be a lot of error because the programmer or scientist can omit many variables.

There are some many interrelations and non-lineal differential equations... It is literally a simulation of the earth itself... yet if we simulate the earth in a super computer we could be wrong because there is no way to predict the human behavior towards earth in the future...

[Llorin]