4 ms·

We'd have to cover too much land with solar panels. What we need are more nuclear power plants, but no one will build them anymore.

yk 13y ago
You need something like half of the Sahara to produce the global primary energy consumption from solar panels alone. [1] ( Or the next few largest deserts combined.) So this is certainly not easy, but it is on the scale of doable. On the other hand, there are reasons why no one has ever tried to finance a nuclear power plant out of his own pockets, it is basically a bet on the interest rate of the next 30 years. ( And besides, we see in Germany that nuclear power gets slaughtered in the market when there is too much renewable energy. [2]) [1] 100 TW primary energy, 100 W/m^2 for solar irradiation on earth and 20% efficiency of the solar cells. Then you need 5e6 m^2. [2] http://www.bloomberg.com/news/2010-04-22/windmill-boom-curbs-electric-power-prices.html http://www.bloomberg.com/news/2010-04-22/windmill-boom-curbs...
- moocowduckquack 13y ago
  [1] 100 TW primary energy An article by MIT claims 14TW - http://web.mit.edu/newsoffice/2011/energy-scale-part1-1024.html http://web.mit.edu/newsoffice/2011/energy-scale-part1-1024.h... - and I've seen figures from 12TW to 20TW bandied around and I tend to use 18TW when running the numbers, but I have never seen an estimate as high as 100TW. Where's that figure from?
  - yk 13y ago
    Ups, good catch. It is from a old blog post from myself [1]. The reasoning was 10 billion people, with first world energy needs ( 10 kW). The alternative to use this number is, that you get a safety factor of 6 to account for using solar as baseload, weather and everything else that dissipates energy. Edit: Additionally, the power of solar panels used is for England, not the Sahara. The purpose of the posting was essentially a back of the envelope calculation with pessimistic assumptions. [1] http://yoshi-k.de/2008/09/die-plausibilitat-der-solarenergie/ http://yoshi-k.de/2008/09/die-plausibilitat-der-solarenergie... ( German)
    - moocowduckquack 13y ago
      You don't need to get everyone in the world to be consuming more energy than the average European to have converted most energy to solar though. I am all for using fudge-factors to allow for rough data, but I don't see the point in starting a calculation with completely fictional data when there is data available.
      - yk 13y ago
        Well, I like my 100% renewable future with flying cars. So I allow for some growth of energy consumption.
        moocowduckquack 13y ago
        Flying cars? Ok, I'm sold, half the Sahara it is.
masklinn 13y ago
There's a lot of land not being used. And of course we can (and should) do both at the same time, and windfarms as well.
JonFish85 13y ago
There are a ton of roadblocks to nuclear power, unfortunately. Although I agree with you that, done right, nuclear is the way to go, it's a tough road to get to. Perhaps biggest, at least in the USA, there is the "Not in my backyard" syndrome. We all want clean energy, but we don't want the chance of a meltdown happening near us / our kids / our workplace. Then there are the coal workers--there are a LOT of jobs tied up here, and it would be political suicide to tell a huge chunk of Southeast America that their job is going away. Then there's the question of other countries. We can make all the changes we want here in the USA, but what do we do about China, Brazil, etc? Any developing country is going to want to trade emissions for growth. China's been doing it for decades and is just now starting to wonder if maybe they should clean up the air. We still breathe that same air, how do we get them not to foul it up? Do we encourage them to build nuclear reactors? Do we have to inspect them to make sure they're safe? Maybe they don't care if a meltdown happens every 5 years, but again, that fouls up our air/waters as well.
moocowduckquack 13y ago
We'd need less than the current roofspace. Compared to existing enterprises like agriculture, the land use is pretty small. Is still huge, of course, like the same size as Spain, or just over half of Texas, but spread out globally that is technically reasonable to achieve. edit - The problem with most nuclear technology, is that if you are looking for a solution to global energy, it has to be something that you are not going to be scared of your enemy possessing. Nuclear might be cheaper to implement in some scenarios, but it is geopolitically screwed as a ubiquitous energy source.
pchristensen 13y ago
Turns out it's not that much[1]. Roughly covering Japan or Germany (not an Axis thing, they're just the right size [2]) would provide enough solar power for the world. [1] http://gizmodo.com/5350191/how-many-solar-panels-would-it-take-to-power-the-entire-world http://gizmodo.com/5350191/how-many-solar-panels-would-it-ta... [2] http://en.wikipedia.org/wiki/List_of_countries_by_area http://en.wikipedia.org/wiki/List_of_countries_by_area

yk 13y ago

You need something like half of the Sahara to produce the global primary energy consumption from solar panels alone. [1] ( Or the next few largest deserts combined.) So this is certainly not easy, but it is on the scale of doable. On the other hand, there are reasons why no one has ever tried to finance a nuclear power plant out of his own pockets, it is basically a bet on the interest rate of the next 30 years. ( And besides, we see in Germany that nuclear power gets slaughtered in the market when there is too much renewable energy. [2]) [1] 100 TW primary energy, 100 W/m^2 for solar irradiation on earth and 20% efficiency of the solar cells. Then you need 5e6 m^2. [2] http://www.bloomberg.com/news/2010-04-22/windmill-boom-curbs-electric-power-prices.html http://www.bloomberg.com/news/2010-04-22/windmill-boom-curbs...

moocowduckquack 13y ago
[1] 100 TW primary energy An article by MIT claims 14TW - http://web.mit.edu/newsoffice/2011/energy-scale-part1-1024.html http://web.mit.edu/newsoffice/2011/energy-scale-part1-1024.h... - and I've seen figures from 12TW to 20TW bandied around and I tend to use 18TW when running the numbers, but I have never seen an estimate as high as 100TW. Where's that figure from?
- yk 13y ago
  Ups, good catch. It is from a old blog post from myself [1]. The reasoning was 10 billion people, with first world energy needs ( 10 kW). The alternative to use this number is, that you get a safety factor of 6 to account for using solar as baseload, weather and everything else that dissipates energy. Edit: Additionally, the power of solar panels used is for England, not the Sahara. The purpose of the posting was essentially a back of the envelope calculation with pessimistic assumptions. [1] http://yoshi-k.de/2008/09/die-plausibilitat-der-solarenergie/ http://yoshi-k.de/2008/09/die-plausibilitat-der-solarenergie... ( German)
  - moocowduckquack 13y ago
    You don't need to get everyone in the world to be consuming more energy than the average European to have converted most energy to solar though. I am all for using fudge-factors to allow for rough data, but I don't see the point in starting a calculation with completely fictional data when there is data available.
    - yk 13y ago
      Well, I like my 100% renewable future with flying cars. So I allow for some growth of energy consumption.
      - moocowduckquack 13y ago
        Flying cars? Ok, I'm sold, half the Sahara it is.

masklinn 13y ago

There's a lot of land not being used. And of course we can (and should) do both at the same time, and windfarms as well.

JonFish85 13y ago

There are a ton of roadblocks to nuclear power, unfortunately. Although I agree with you that, done right, nuclear is the way to go, it's a tough road to get to. Perhaps biggest, at least in the USA, there is the "Not in my backyard" syndrome. We all want clean energy, but we don't want the chance of a meltdown happening near us / our kids / our workplace. Then there are the coal workers--there are a LOT of jobs tied up here, and it would be political suicide to tell a huge chunk of Southeast America that their job is going away. Then there's the question of other countries. We can make all the changes we want here in the USA, but what do we do about China, Brazil, etc? Any developing country is going to want to trade emissions for growth. China's been doing it for decades and is just now starting to wonder if maybe they should clean up the air. We still breathe that same air, how do we get them not to foul it up? Do we encourage them to build nuclear reactors? Do we have to inspect them to make sure they're safe? Maybe they don't care if a meltdown happens every 5 years, but again, that fouls up our air/waters as well.

moocowduckquack 13y ago

We'd need less than the current roofspace. Compared to existing enterprises like agriculture, the land use is pretty small. Is still huge, of course, like the same size as Spain, or just over half of Texas, but spread out globally that is technically reasonable to achieve. edit - The problem with most nuclear technology, is that if you are looking for a solution to global energy, it has to be something that you are not going to be scared of your enemy possessing. Nuclear might be cheaper to implement in some scenarios, but it is geopolitically screwed as a ubiquitous energy source.

pchristensen 13y ago

Turns out it's not that much[1]. Roughly covering Japan or Germany (not an Axis thing, they're just the right size [2]) would provide enough solar power for the world. [1] http://gizmodo.com/5350191/how-many-solar-panels-would-it-take-to-power-the-entire-world http://gizmodo.com/5350191/how-many-solar-panels-would-it-ta... [2] http://en.wikipedia.org/wiki/List_of_countries_by_area http://en.wikipedia.org/wiki/List_of_countries_by_area