4 ms·

Surface area required to power the whole world by solar power

18 points by obsaysditto 16y ago

mseebach 16y ago
The area needed is not really a problem for solar power. It's storage. We need power when it's dark, probably even more then than when there's daylight.
- lhorie 16y ago
  You know solar panel systems often have batteries, right?
  - mseebach 16y ago
    Yep. I also know that they're pretty inefficient and expensive and toxic to manufacture and dispose of. Which makes them a problem for large-scale solar installations. Solar is great for when there's sun. Once the sun's out, not so much.
    - lhorie 16y ago
      I remember reading somewhere a while back that the investment in solar panels doesn't really pay off because of the somewhat low life expectancy (~10 years) and high costs. Is that because of the batteries also?
- ugh 16y ago
  Also, any human artifact which shows up as a box – not a dot – on a map of this scale is pretty darn huge. We currently probably couldn’t even manufacture all the solar panels or mirrors required, even if we wanted to. Long distance power transfer might alleviate some power storage worries, but that is a huge engineering challenge in itself. It would also increase the required area – probably considerably – and we would – again – end up with a centralized power system which absolutely depends on international cooperation, you know, kinda like oil (not to say that’s a bad thing, it just adds another point of failure). That’s not to say solar power is forever and always not feasible. I think it’s an interesting challenge and we might expect at least some success.
- zokier 16y ago
  Hydrogen could be a solution for storage, transportation. And there is a possibility to find a more direct way to produce hydrogen with solar power that photovoltaics and electrolysis.
  - aidenn0 16y ago
    Hydrogen via electrolysis is not a good solution for grid-scale storage. The cycle efficiency is just way too low.
    - mseebach 16y ago
      Correct me if I'm wrong, but it seems that the world has moved away from hydrogen in favor of batteries? There's the cycle efficiency, but it's probably also a factor that we have a very well developed infrastructure for shipping electrical power around, while pretty much none for hydrogen.
- bulanga 16y ago
  That's right, storage is all too often forgotten. Some ways energy can be stored: - kinetic energy storage e.g. spinning flywheel - potential energy storage e.g. pump water at an altitude - thermal energy e.g I read somewhere that molten salt can store heat for hours. i.e. steam can be produced to spin a turbine.
- nfnaaron 16y ago
  So implement storage. Build more capacity than you need for momentary power and use the excess to charge batteries or raise water columns. Build still more excess capacity, charge local storage at the solar plant or at intermediate locations, and use the rest of the excess at the point of consumption to charge storage there. That's a lot of solar generators. So the sooner we start, the sooner we'll get there. The interesting thing is, just as better computers help us design and build still better computers, increasingly available energy will drive the cost of existing energy down, reducing the cost of energy used to build and maintain new capacity. If we can only power the world half the day with solar, then that's a large fraction of our power that we don't have to burn oil or coal or biomass (food) for. If we can only power half the world half the day, it's still a win. If we can only make it through part of the night before lighting up an oil generator, it's still a win. It astounds me that we're living in a blowtorch and we do essentially nothing with it, fight wars over oil, spew oil and emissions all over the world, and watch the elderly and poor die from lack of heat or cooling.
  - InclinedPlane 16y ago
    If you need to build a complete parallel power generation infrastructure which must be capable of satisfying peak power demand on its own then it's almost irrelevant whether that infrastructure is battery powered or coal powered (from an economics standpoint). Not to mention that nobody's created anything even remotely capable of being used to generate peak (or even base) power loads using only stored energy. This tidy infographic makes it seem like we could start the switch to PV power tomorrow if only we really cared to do so. However, the truth is far different. Not only do we lack the manufacturing capacity, by orders of magnitude, to produce enough PV panels, we do not have the operational experience in creating the sort of power storage systems that would be necessary if PV sources dominated base electrical power generation. This is not a solved problem.
  - anamax 16y ago
    > So implement storage. Build more capacity than you need for momentary power and use the excess to charge batteries or raise water columns. Build still more excess capacity, charge local storage at the solar plant or at intermediate locations, and use the rest of the excess at the point of consumption to charge storage there. You're assuming that that's economically viable. If it is, why aren't you going all-in with your money? > That's a lot of solar generators. So the sooner we start, the sooner we'll get there. Nope. We'll end up with a lot of old-tech solar that isn't as good as what we'll get by waiting. > If we can only make it through part of the night before lighting up an oil generator, it's still a win. Only if you ignore costs. Spending $100 today on a solar system that is half as cost-effective as one that becomes available in 2 years is a good idea in some circumstances but not all. That's relevant because solar systems are not static. > increasingly available energy will drive the cost of existing energy down That's not necessarily true. It depends on costs. For example, we can get energy by burning diamonds. However, doing so will not drive the cost of existing energy down.
DanielStraight 16y ago
I can't get the original to load, but at least this page links to it: http://www.treehugger.com/files/2009/09/surface-area-required-to-power-the-whole-world-with-solar-power-wind.php http://www.treehugger.com/files/2009/09/surface-area-require...
- zokier 16y ago
  http://www.landartgenerator.org/blagi/?p=127 http://www.landartgenerator.org/blagi/?p=127 Seems to be the actual source. It's kinda annoying that you need to hunt it like you do.
aidenn0 16y ago
So anyone who thinks we can manufacture nearly 500 billion square meters of solar panels by 2030, raise your hand. It seems clear that if we were to do this it couldn't be all photovoltaics. Even with concentrating solar cells that's a lot of silicon and/or more rare elements (indium etc.). With solar-thermal added into the mix it becomes potentially feasible, but who is going to fund a huge solar farm in the middle of a politically unstable region like north africa?
- conover 16y ago
  Another technical problem is that you have to transmit all that power somehow. I'm no expert but I would imagine that you would need orders of magnitude higher voltage transmission lines (or more of them) than currently exist. Also, the geography of most of those location is pretty intense.
chaosmachine 16y ago
The infographic claims it will take about 500000 square kilometers of solar panels. 1 square kilometer is one million square meters (1000x1000). At a cost of $100 per square meter, that's $100,000,000 (one hundred million dollars) to complete 1/500000th of the project. Did I make any mistakes?
- zokier 16y ago
  Google says: (500 000 (km^2)) * 100 (U.S. dollars / (m^2)) = 50 trillion U.S. dollars http://www.google.com/search?hl=en&q=500000+km^2+*+100+USD+%2F+m^2 http://www.google.com/search?hl=en&q=500000+km^2+*+100+U...
  - asmithmd1 16y ago
    While that is a huge number it is not out of the realm of possibility. According to Wikipedia the world's GDP was $57 trillion last year. So we devote 8% of our output to this project and in 10 years the whole planet is energy independent
    - icegreentea 16y ago
      8 percent? Good luck getting the world to just 'divert' 8% of their GDP to build this stuff. That much vaunted US military spending? The one that outspends the entire rest of the world? That's 4% of your GDP.
  - lutorm 16y ago
    To put that in perspective: Current global oil use, 75e6 barrels per day, at current price of $75/barrel = 2 trillion US dollars per year. It's the same cost as 25 years of oil production, at current prices. Even if you think oil price won't go up and solar panel price won't come down, that doesn't seem economically crazy. 25 years is probably about the lifetime of the solar installations. Infrastructure is a big cost, but the only difference is that the infrastructure cost for oil has already been sunk. It's a one-time changeover cost and eventually there will be no oil.
jmhobbs 16y ago
Let's just go ahead and start on the Dyson Sphere.
WiseWeasel 16y ago
Finally, a good use for Arizona.
terra_t 16y ago
Not "with solar panels alone" but with lots of batteries. Seawater Uranium and Thorium from Monazite are much more credible energy resources.
techiferous 16y ago
This surface area is roughly equivalent to the size of Montana (or the size of Germany).
RyanMcGreal 16y ago
The linked page on what will happen in 2012 [1] doesn't increase my confidence in the information presented herein. [1] http://www.2012officialcountdown.com/?a=osn2003 http://www.2012officialcountdown.com/?a=osn2003
azim 16y ago
There has been some pretty interesting research in to storing energy in molten salts. This is a bit different than the photovoltaic cells which I believe this map is referencing; It involves capturing heat and turning it in to electricity rather than light. This is mainly just research right now, but if it pans out it could potentially be much more practical than photovoltaic cells because it doesn't require as many precious materials to manufacture and stores energy at night. See: http://en.wikipedia.org/wiki/Solar_power_tower http://en.wikipedia.org/wiki/Solar_power_tower and http://en.wikipedia.org/wiki/Thermal_energy_storage http://en.wikipedia.org/wiki/Thermal_energy_storage

18 points by obsaysditto 16y ago

The area needed is not really a problem for solar power. It's storage. We need power when it's dark, probably even more then than when there's daylight.

lhorie 16y ago
You know solar panel systems often have batteries, right?
- mseebach 16y ago
  Yep. I also know that they're pretty inefficient and expensive and toxic to manufacture and dispose of. Which makes them a problem for large-scale solar installations. Solar is great for when there's sun. Once the sun's out, not so much.
  - lhorie 16y ago
    I remember reading somewhere a while back that the investment in solar panels doesn't really pay off because of the somewhat low life expectancy (~10 years) and high costs. Is that because of the batteries also?
ugh 16y ago
Also, any human artifact which shows up as a box – not a dot – on a map of this scale is pretty darn huge. We currently probably couldn’t even manufacture all the solar panels or mirrors required, even if we wanted to. Long distance power transfer might alleviate some power storage worries, but that is a huge engineering challenge in itself. It would also increase the required area – probably considerably – and we would – again – end up with a centralized power system which absolutely depends on international cooperation, you know, kinda like oil (not to say that’s a bad thing, it just adds another point of failure). That’s not to say solar power is forever and always not feasible. I think it’s an interesting challenge and we might expect at least some success.
zokier 16y ago
Hydrogen could be a solution for storage, transportation. And there is a possibility to find a more direct way to produce hydrogen with solar power that photovoltaics and electrolysis.
- aidenn0 16y ago
  Hydrogen via electrolysis is not a good solution for grid-scale storage. The cycle efficiency is just way too low.
  - mseebach 16y ago
    Correct me if I'm wrong, but it seems that the world has moved away from hydrogen in favor of batteries? There's the cycle efficiency, but it's probably also a factor that we have a very well developed infrastructure for shipping electrical power around, while pretty much none for hydrogen.
bulanga 16y ago
That's right, storage is all too often forgotten. Some ways energy can be stored: - kinetic energy storage e.g. spinning flywheel - potential energy storage e.g. pump water at an altitude - thermal energy e.g I read somewhere that molten salt can store heat for hours. i.e. steam can be produced to spin a turbine.
nfnaaron 16y ago
So implement storage. Build more capacity than you need for momentary power and use the excess to charge batteries or raise water columns. Build still more excess capacity, charge local storage at the solar plant or at intermediate locations, and use the rest of the excess at the point of consumption to charge storage there. That's a lot of solar generators. So the sooner we start, the sooner we'll get there. The interesting thing is, just as better computers help us design and build still better computers, increasingly available energy will drive the cost of existing energy down, reducing the cost of energy used to build and maintain new capacity. If we can only power the world half the day with solar, then that's a large fraction of our power that we don't have to burn oil or coal or biomass (food) for. If we can only power half the world half the day, it's still a win. If we can only make it through part of the night before lighting up an oil generator, it's still a win. It astounds me that we're living in a blowtorch and we do essentially nothing with it, fight wars over oil, spew oil and emissions all over the world, and watch the elderly and poor die from lack of heat or cooling.
- InclinedPlane 16y ago
  If you need to build a complete parallel power generation infrastructure which must be capable of satisfying peak power demand on its own then it's almost irrelevant whether that infrastructure is battery powered or coal powered (from an economics standpoint). Not to mention that nobody's created anything even remotely capable of being used to generate peak (or even base) power loads using only stored energy. This tidy infographic makes it seem like we could start the switch to PV power tomorrow if only we really cared to do so. However, the truth is far different. Not only do we lack the manufacturing capacity, by orders of magnitude, to produce enough PV panels, we do not have the operational experience in creating the sort of power storage systems that would be necessary if PV sources dominated base electrical power generation. This is not a solved problem.
- anamax 16y ago
  > So implement storage. Build more capacity than you need for momentary power and use the excess to charge batteries or raise water columns. Build still more excess capacity, charge local storage at the solar plant or at intermediate locations, and use the rest of the excess at the point of consumption to charge storage there. You're assuming that that's economically viable. If it is, why aren't you going all-in with your money? > That's a lot of solar generators. So the sooner we start, the sooner we'll get there. Nope. We'll end up with a lot of old-tech solar that isn't as good as what we'll get by waiting. > If we can only make it through part of the night before lighting up an oil generator, it's still a win. Only if you ignore costs. Spending $100 today on a solar system that is half as cost-effective as one that becomes available in 2 years is a good idea in some circumstances but not all. That's relevant because solar systems are not static. > increasingly available energy will drive the cost of existing energy down That's not necessarily true. It depends on costs. For example, we can get energy by burning diamonds. However, doing so will not drive the cost of existing energy down.

DanielStraight 16y ago

I can't get the original to load, but at least this page links to it: http://www.treehugger.com/files/2009/09/surface-area-required-to-power-the-whole-world-with-solar-power-wind.php http://www.treehugger.com/files/2009/09/surface-area-require...

zokier 16y ago
http://www.landartgenerator.org/blagi/?p=127 http://www.landartgenerator.org/blagi/?p=127 Seems to be the actual source. It's kinda annoying that you need to hunt it like you do.

aidenn0 16y ago

So anyone who thinks we can manufacture nearly 500 billion square meters of solar panels by 2030, raise your hand. It seems clear that if we were to do this it couldn't be all photovoltaics. Even with concentrating solar cells that's a lot of silicon and/or more rare elements (indium etc.). With solar-thermal added into the mix it becomes potentially feasible, but who is going to fund a huge solar farm in the middle of a politically unstable region like north africa?

conover 16y ago
Another technical problem is that you have to transmit all that power somehow. I'm no expert but I would imagine that you would need orders of magnitude higher voltage transmission lines (or more of them) than currently exist. Also, the geography of most of those location is pretty intense.

chaosmachine 16y ago

The infographic claims it will take about 500000 square kilometers of solar panels. 1 square kilometer is one million square meters (1000x1000). At a cost of $100 per square meter, that's $100,000,000 (one hundred million dollars) to complete 1/500000th of the project. Did I make any mistakes?

zokier 16y ago
Google says: (500 000 (km^2)) * 100 (U.S. dollars / (m^2)) = 50 trillion U.S. dollars http://www.google.com/search?hl=en&q=500000+km^2+*+100+USD+%2F+m^2 http://www.google.com/search?hl=en&q=500000+km^2+*+100+U...
- asmithmd1 16y ago
  While that is a huge number it is not out of the realm of possibility. According to Wikipedia the world's GDP was $57 trillion last year. So we devote 8% of our output to this project and in 10 years the whole planet is energy independent
  - icegreentea 16y ago
    8 percent? Good luck getting the world to just 'divert' 8% of their GDP to build this stuff. That much vaunted US military spending? The one that outspends the entire rest of the world? That's 4% of your GDP.
- lutorm 16y ago
  To put that in perspective: Current global oil use, 75e6 barrels per day, at current price of $75/barrel = 2 trillion US dollars per year. It's the same cost as 25 years of oil production, at current prices. Even if you think oil price won't go up and solar panel price won't come down, that doesn't seem economically crazy. 25 years is probably about the lifetime of the solar installations. Infrastructure is a big cost, but the only difference is that the infrastructure cost for oil has already been sunk. It's a one-time changeover cost and eventually there will be no oil.

jmhobbs 16y ago

Let's just go ahead and start on the Dyson Sphere.

WiseWeasel 16y ago

Finally, a good use for Arizona.

terra_t 16y ago

Not "with solar panels alone" but with lots of batteries. Seawater Uranium and Thorium from Monazite are much more credible energy resources.

techiferous 16y ago

This surface area is roughly equivalent to the size of Montana (or the size of Germany).

RyanMcGreal 16y ago

The linked page on what will happen in 2012 [1] doesn't increase my confidence in the information presented herein. [1] http://www.2012officialcountdown.com/?a=osn2003 http://www.2012officialcountdown.com/?a=osn2003

azim 16y ago

There has been some pretty interesting research in to storing energy in molten salts. This is a bit different than the photovoltaic cells which I believe this map is referencing; It involves capturing heat and turning it in to electricity rather than light. This is mainly just research right now, but if it pans out it could potentially be much more practical than photovoltaic cells because it doesn't require as many precious materials to manufacture and stores energy at night. See: http://en.wikipedia.org/wiki/Solar_power_tower http://en.wikipedia.org/wiki/Solar_power_tower and http://en.wikipedia.org/wiki/Thermal_energy_storage http://en.wikipedia.org/wiki/Thermal_energy_storage