Welcome to Gaia! ::


I was just wondering...

Have someone ever calculated the maximum number of people that can live with all their fulfilled basic needs?

I am sure that someone have calculated that or simulated, but I do not know where to find it.

And what limits its carrying capacity? food , water, health, space?

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 ?
(reserved for conclusions)

Fanatical Zealot

It is 5 million.

So we have far exceeded, and all humans are doomed to die at some point!


To be honest it's a lot more than that, but it's somewhere around 60 billion or so, I keep getting.

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.


But the truth is with simple things like irrigation and fertilizer, or aquaponics, you can essentially create or reduce a need for farmland in the first place, and so limits on food and water are almost non existent when considered in that criteria.

Space is pretty much a non issue. Water is a non-issue. Food is relatively easy to solve. With recycling and the awesome size of the earth there's not much of a problem with natural resources like iron and silicon.


Since energy can be alleviated with Thorium, and in the future hopefully graphene solar panels, we'll be fine. 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. So since energy is your biggest concern and that can be alleviated by Thorium, we'll be okay. We will run out of energy but, with solar panels we could have enormous amounts of energy; something like 8000 times our annual energy usage hits the earth every day or something crazy like that. We only need to capture a portion of that to power the world so. Energy isn't a real problem; by the time we run out of cheap gasoline we'll likely have established these as main power sources and we'll have energy for billions of years.

SO YEAH!

Beloved Elder

Estimates differ widely depending on what you consider a basic need and how much land you reserve for wildlife.

Wikipedia says
Quote:
Most estimates for the carrying capacity of the Earth are between 4 billion and 16 billion. Depending on which estimate is used, human overpopulation may or may not have already occurred.
Suicidesoldier#1
It is 5 million.

So we have far exceeded, and all humans are doomed to die at some point!


To be honest it's a lot more than that, but it's somewhere around 60 billion or so, I keep getting.

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.


But the truth is with simple things like irrigation and fertilizer, or aquaponics, you can essentially create or reduce a need for farmland in the first place, and so limits on food and water are almost non existent when considered in that criteria.

Space is pretty much a non issue. Water is a non-issue. Food is relatively easy to solve. With recycling and the awesome size of the earth there's not much of a problem with natural resources like iron and silicon.

Since energy can be alleviated with Thorium, and in the future hopefully graphene solar panels, we'll be fine. 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. So since energy is your biggest concern and that can be alleviated by Thorium, we'll be okay. We will run out of energy but, with solar panels we could have enormous amounts of energy; something like 8000 times our annual energy usage hits the earth every day or something crazy like that. We only need to capture a portion of that to power the world so. Energy isn't a real problem; by the time we run out of cheap gasoline we'll likely have established these as main power sources and we'll have energy for billions of years.

SO YEAH!


Yes, topsoil, water and even space can be solved with large amounts of energy in a limited area. There is no doubt about it... and with infinity amounts of energy it is possible to apply even geoengineering and terraforming.

But what about transportation of people and things or transportation of energy. Is there enough rare earth minerals to make it possible?

Yes there is 4 times more Thorium than Uranium. But there will be a point that the extraction of Thorium will not compensate its EROEI (energy return on energy invested).

User Image - Blocked by "Display Image" Settings. Click to show.
SmallTownGuy
Estimates differ widely depending on what you consider a basic need and how much land you reserve for wildlife.

Wikipedia says
Quote:
Most estimates for the carrying capacity of the Earth are between 4 billion and 16 billion. Depending on which estimate is used, human overpopulation may or may not have already occurred.


I wonder how they do calculate it. Any guess?
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.

Beloved Elder

Llorin
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 are still a dream, but they have promise. The best traditional-design graphene cells so far are only about 8% efficient.

But they're still interesting for several reasons. If you apply a voltage to a bilayer of graphene, it changes from a semi-metal to a semiconductor with a variable band gap between 0 and 0.25 eV (so a cell could absorb a wide range of wavelengths). It's nearly transparent. It has a high thermal conductivity, so it could act as its own heat sink. It doesn't seem to degrade as quickly as silicon cells (which aren't bad either, but an improvement is still an improvement). It's strong, flexible, easily shaped, and easily produced (making it an engineer's dream material).

The hope is that you could eventually stack many bilayers of graphene - cheaply - to produce a cell that absorbs a wide range of wavelengths.
SmallTownGuy
Llorin
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 are still a dream, but they have promise. The best traditional-design graphene cells so far are only about 8% efficient.

But they're still interesting for several reasons. If you apply a voltage to a bilayer of graphene, it changes from a semi-metal to a semiconductor with a variable band gap between 0 and 0.25 eV (so a cell could absorb a wide range of wavelengths). It's nearly transparent. It has a high thermal conductivity, so it could act as its own heat sink. It doesn't seem to degrade as quickly as silicon cells (which aren't bad either, but an improvement is still an improvement). It's strong, flexible, easily shaped, and easily produced (making it an engineer's dream material).

The hope is that you could eventually stack many bilayers of graphene - cheaply - to produce a cell that absorbs a wide range of wavelengths.


But remember that if the energy involved in its construction surpass the energy that can provide in its lifetime, we just can forget about them.

8% at its very best is still too low.

Beloved Elder

Llorin
8% at its very best is still too low.
Everybody agrees. That's why it's still a dream until more radical layered designs become practical.
SmallTownGuy
Llorin
8% at its very best is still too low.
Everybody agrees. That's why it's still a dream until more radical layered designs become practical.


How do they know that it won't keep as a dream forever? Forgive but I have no faith in this technology at such a short time term.
I do not believe in organic photovoltaic cells.

Beloved Elder

How do you know anything about a new material until you work with it? Graphene has so many interesting properties that - even if it doesn't pan out as a photovoltaic - the more we try stuff with it the better. The effort won't be wasted.

And it still might prove useful as a photovoltaic.
It depends on lots of factors that we can't accurately quantify at the moment, like the health of the ecosystem, the metabolic rate of civilization, our level of technology, the parity between consumption of natural resources and their replenishment rate, etc.

Right now, it's probably less than 10B.
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.


Quote:
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.
Quote:
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.
Quote:
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.
Quote:
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.


Do you have the certainty that the energy produced by photovoltaic cells in its lifetime -less its maintenance- surpass the energy that is required to build them?

Quick Reply

Submit
Manage Your Items
Other Stuff
Get GCash
Offers
Get Items
More Items
Where Everyone Hangs Out
Other Community Areas
Virtual Spaces
Fun Stuff
Gaia's Games
Mini-Games
Play with GCash
Play with Platinum