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I love that you bring up the global scale. It's in the global scale things sound daunting. But it's in the global scale that what is really important becomes

I love that you bring up the global scale. It's in the global scale things sound daunting. But it's in the global scale that what is really important becomes clear. Maybe the most important fact it all boils down to is energy density. Nuclear is literally millions of times more energy dense than any other energy source. Practically, that means millions of times less waste. (See let's talk about physics baby http://www.thingsworsethannuclearpower.com/2013/02/energydensityphysicsbaby.html http://www.thingsworsethannuclearpower.com/2013/02/energyden... ) Envision a world powered entirely by coal. Not pretty. Entirely by solar? Appealing PR, but besides being not at all possible it has it's own immense ewaste issues and those never decay away and that waste certainly cannot produce energy. Entirely by hydro? That means destruction of perhaps the largest swaths of ecosystems in the world. Etc. Take any qualms about a globe powered by nuclear and then multiply it almost by millions of times for the other sources. Land use is another huge factor. See this graphic for comparison. http://newenergyandfuel.com/wp-content/uploads/2010/06/LandUseforEnergy-ClintonAndrews.jpg http://newenergyandfuel.com/wp-content/uploads/2010/06/LandU... As far as security forces, etc, it wouldn't likely scale like that but let's assume it does. Are numbers like a million well paying jobs spread worldwide actually daunting? How many military folk end their service time in the US alone each year? I was an intern in the Office of the Secretary of Defense for Economics and Manpower so I should remember but I looked it up. There are hundreds of thousands of former service members looking for jobs each year. ( http://www.civilianjobs.com/careeradvice/related.aspx http://www.civilianjobs.com/careeradvice/related.aspx) Thats leaving out more than 6 billion in other people.

dredmorbius 12y ago
Net of total space requirements for a nuclear reactor site (and not counting processing or mining space), nuclear is only about 2-4x more dense than solar. That is, you could take a nuclear power plant site, remove the reactors, fill it with solar PV, and you'd have ~1/4 - 1/2 the energy output. When you consider that solar energy can be co-sited with many other land-uses, the situation gets even better. Residential, commercial, or industrial buildings, highway rights-of-way (not on the freakin' roadways, but alongside), or of course, high-potential solar in desert or other largely empty space. Coal fails for multiple reasons, including in the long term that there's simply not enough of it: the global R/P ratio is 113, that is, there are 113 years' supply at present rates of use. And that rate is increasing -- the R/P ratio has fallen from above 200 in 1993 to just over 100 in 2013. Source: BP Statistical Review of World Energy, June, 2014 http://bp.com/statisticalreview http://bp.com/statisticalreview Then there's that little issue about global warming. Solar has markedly little waste issue. The life of PV panels is 20-25 years, they're comprised largely of silicon, and other materials can be recycled from them. Total present US energy usage (not just electricity generation) could be provided from a region 233 miles on a side (54,400 mi^2). Via GNU units and some fairly standard values: You have: 100 quad / (1 kW/m^2 * 0.3 * 0.17 * 0.9 * 0.55 * 0.94 * 1 year ) You want: mi^2 * 54397.603 / 1.8383163e-05 You have: sqrt(54397.603) You want: Definition: 233.23294 Switch instead to solar thermal, and you're now free of virtually any The more significant problem is that there are more humans, consuming more resources, by a long stretch, than the Earth can support. We might be able to provide for 3-4 billions sustainably, but at a standard of living equivalent to slums of Manilla, Kolkata, or the favellas of Rio. Or worse. Or 500 million to 2 billion at a higher rate of resource consumption, though likely markedly lower than that of the present-day US. The thing about those 1.8 million security forces is that they represent themselves a vast level of resource allocation that's not itself directly productive. It's an overhead that other energy systems don't require. Your land-area charts mostly show that biofuels aren't viable. I don't disagree with that conclusion: http://www.reddit.com/r/dredmorbius/comments/2cvap7/the_intractable_problem_of_biomass_for_fuels_is/ http://www.reddit.com/r/dredmorbius/comments/2cvap7/the_intr... (More: http://www.reddit.com/r/dredmorbius/search?q=biofuels&restrict_sr=on&sort=relevance&t=all http://www.reddit.com/r/dredmorbius/search?q=biofuels&restri...) Note that the delta for nuclear and solar isn't particularly significant, again noting that solar power can be co-located with other land uses. I'd also strongly suggest you actually read and view my references before responding, as several of these aspects are addressed. And you've wholly avoided addressing the large-scale, long-term, unavoidable systemic risks of nuclear.
TheLoneWolfling 12y ago
Something to take note of. Different types of energy production are useful for different roles. Nuclear tends to fall into the category of base load - it costs (close enough to) just as much to run it at 5% capacity as at 100%. Most traditional fossil-fuel steam turbines (coal, oil) have spin-up times on the order of several hours to a day. As such, they tend to be used to compensate for longer-timescale variations, but cannot really cope with very short term spikes. There are fossil-fuel power stations with shorter lag times, but they tend to be relatively inefficient, and as such only get used for unexpected high loads. Hydro is really good in a lot of ways, at least where hydro power stations can be built. The biggest reason is that it can be adjusted on really short timescales. Read: minutes or less. Longer lag time for larger power stations - the biggest limitation tends to be preventing cavitation and water hammer. Solar and wind are both extremely variable, and unpredictably so (you can predict, but there is enough inaccuracy in the predictions that you cannot trust them). As such, they are practically useless without at least one of power storage, fast-responding power generation, or fast-acting power usage cuts when necessary. (Read: hydro or paying aluminum smelters to only run in the back shifts. (First thing that came to mind)) As there is no efficient and decently long-lasting power storage at grid scales (Vanadium-redox batteries are good, but have issues. Molten-salt storage leaks heat quickly. Etc.), effectively: you can forget about solar and wind for grid-scale power without hydro. Nuclear power for everything is a waste unless society changes. And good luck with that.
- dredmorbius 12y ago
  Quite. Hydro, hydro pumped storage, tidal impounds (essentially low-head but large-area reservoirs), and geothermal (wet field) are all highly dispatchable. Solar thermal is expensive but among its benefits it has is a built-in storage capability. For most present plants that's only a few hours, but several days worth of banked heat might be viable. There are a number of storage options, of which the prospect of synfuels, in particular seawater-based Fischer-Tropsch fuel synthesis, which as been studied by Brookhaven National Labs, MIT, and the US Naval Research Lab for over 50 years, looks fairly promising. It starts with hydrogen electrolysis, to which CO2 is added, sourced from seawater. Outputs are analogs of present day diesel, gasoline, natural gas, or other hydrocarbons. Most of the energy cost is in the electrolysis. Net energy return in terms of fuel is about 50-60%, round-trip net of generation would be fairly low (~20%), but the energy storage is very long-term stable, and dense by weight or volume (for liquids). We've got a lot of experience burning hydrocarbons, and these are carbon-neutral (the source CO2 comes from the present biosphere). http://www.reddit.com/r/dredmorbius/comments/28nqoz/electrical_fuel_synthesis_from_seawater_older/ http://www.reddit.com/r/dredmorbius/comments/28nqoz/electric... http://www.reddit.com/r/dredmorbius/comments/22k71x/us_navy_electricitytofuel_synthesis_papers_and/ http://www.reddit.com/r/dredmorbius/comments/22k71x/us_navy_... There's also work by some (including a recent video by Amory Lovins) suggesting that there are relatively modest requirements for dispatchable generation, though I suspect those are a tad optimistic. http://www.engineering.com/ElectronicsDesign/ElectronicsDesignArticles/ArticleID/8272/Is-Storage-Necessary-for-Renewable-Energy.aspx?ENGCOM= http://www.engineering.com/ElectronicsDesign/ElectronicsDesi... https://www.youtube.com/watch?v=MsgrahFln0s https://www.youtube.com/watch?v=MsgrahFln0s
dredmorbius 12y ago
NB: source of that land use chart: http://www.lincolninst.edu/pubs/2036_Alternative-Energy-Sources-and-Land-Use http://www.lincolninst.edu/pubs/2036_Alternative-Energy-Sour... http://newenergyandfuel.com/http:/newenergyandfuel/com/2010/06/08/how-to-use-the-land/landuseforenergy-clintonandrews/ http://newenergyandfuel.com/http:/newenergyandfuel/com/2010/... http://www.cnet.com/news/figuring-land-use-into-renewable-energy-equation/ http://www.cnet.com/news/figuring-land-use-into-renewable-en...

dredmorbius 12y ago

Net of total space requirements for a nuclear reactor site (and not counting processing or mining space), nuclear is only about 2-4x more dense than solar. That is, you could take a nuclear power plant site, remove the reactors, fill it with solar PV, and you'd have ~1/4 - 1/2 the energy output. When you consider that solar energy can be co-sited with many other land-uses, the situation gets even better. Residential, commercial, or industrial buildings, highway rights-of-way (not on the freakin' roadways, but alongside), or of course, high-potential solar in desert or other largely empty space. Coal fails for multiple reasons, including in the long term that there's simply not enough of it: the global R/P ratio is 113, that is, there are 113 years' supply at present rates of use. And that rate is increasing -- the R/P ratio has fallen from above 200 in 1993 to just over 100 in 2013. Source: BP Statistical Review of World Energy, June, 2014 http://bp.com/statisticalreview http://bp.com/statisticalreview Then there's that little issue about global warming. Solar has markedly little waste issue. The life of PV panels is 20-25 years, they're comprised largely of silicon, and other materials can be recycled from them. Total present US energy usage (not just electricity generation) could be provided from a region 233 miles on a side (54,400 mi^2). Via GNU units and some fairly standard values: You have: 100 quad / (1 kW/m^2 * 0.3 * 0.17 * 0.9 * 0.55 * 0.94 * 1 year ) You want: mi^2 * 54397.603 / 1.8383163e-05 You have: sqrt(54397.603) You want: Definition: 233.23294 Switch instead to solar thermal, and you're now free of virtually any The more significant problem is that there are more humans, consuming more resources, by a long stretch, than the Earth can support. We might be able to provide for 3-4 billions sustainably, but at a standard of living equivalent to slums of Manilla, Kolkata, or the favellas of Rio. Or worse. Or 500 million to 2 billion at a higher rate of resource consumption, though likely markedly lower than that of the present-day US. The thing about those 1.8 million security forces is that they represent themselves a vast level of resource allocation that's not itself directly productive. It's an overhead that other energy systems don't require. Your land-area charts mostly show that biofuels aren't viable. I don't disagree with that conclusion: http://www.reddit.com/r/dredmorbius/comments/2cvap7/the_intractable_problem_of_biomass_for_fuels_is/ http://www.reddit.com/r/dredmorbius/comments/2cvap7/the_intr... (More: http://www.reddit.com/r/dredmorbius/search?q=biofuels&restrict_sr=on&sort=relevance&t=all http://www.reddit.com/r/dredmorbius/search?q=biofuels&restri...) Note that the delta for nuclear and solar isn't particularly significant, again noting that solar power can be co-located with other land uses. I'd also strongly suggest you actually read and view my references before responding, as several of these aspects are addressed. And you've wholly avoided addressing the large-scale, long-term, unavoidable systemic risks of nuclear.

TheLoneWolfling 12y ago

Something to take note of. Different types of energy production are useful for different roles. Nuclear tends to fall into the category of base load - it costs (close enough to) just as much to run it at 5% capacity as at 100%. Most traditional fossil-fuel steam turbines (coal, oil) have spin-up times on the order of several hours to a day. As such, they tend to be used to compensate for longer-timescale variations, but cannot really cope with very short term spikes. There are fossil-fuel power stations with shorter lag times, but they tend to be relatively inefficient, and as such only get used for unexpected high loads. Hydro is really good in a lot of ways, at least where hydro power stations can be built. The biggest reason is that it can be adjusted on really short timescales. Read: minutes or less. Longer lag time for larger power stations - the biggest limitation tends to be preventing cavitation and water hammer. Solar and wind are both extremely variable, and unpredictably so (you can predict, but there is enough inaccuracy in the predictions that you cannot trust them). As such, they are practically useless without at least one of power storage, fast-responding power generation, or fast-acting power usage cuts when necessary. (Read: hydro or paying aluminum smelters to only run in the back shifts. (First thing that came to mind)) As there is no efficient and decently long-lasting power storage at grid scales (Vanadium-redox batteries are good, but have issues. Molten-salt storage leaks heat quickly. Etc.), effectively: you can forget about solar and wind for grid-scale power without hydro. Nuclear power for everything is a waste unless society changes. And good luck with that.

dredmorbius 12y ago
Quite. Hydro, hydro pumped storage, tidal impounds (essentially low-head but large-area reservoirs), and geothermal (wet field) are all highly dispatchable. Solar thermal is expensive but among its benefits it has is a built-in storage capability. For most present plants that's only a few hours, but several days worth of banked heat might be viable. There are a number of storage options, of which the prospect of synfuels, in particular seawater-based Fischer-Tropsch fuel synthesis, which as been studied by Brookhaven National Labs, MIT, and the US Naval Research Lab for over 50 years, looks fairly promising. It starts with hydrogen electrolysis, to which CO2 is added, sourced from seawater. Outputs are analogs of present day diesel, gasoline, natural gas, or other hydrocarbons. Most of the energy cost is in the electrolysis. Net energy return in terms of fuel is about 50-60%, round-trip net of generation would be fairly low (~20%), but the energy storage is very long-term stable, and dense by weight or volume (for liquids). We've got a lot of experience burning hydrocarbons, and these are carbon-neutral (the source CO2 comes from the present biosphere). http://www.reddit.com/r/dredmorbius/comments/28nqoz/electrical_fuel_synthesis_from_seawater_older/ http://www.reddit.com/r/dredmorbius/comments/28nqoz/electric... http://www.reddit.com/r/dredmorbius/comments/22k71x/us_navy_electricitytofuel_synthesis_papers_and/ http://www.reddit.com/r/dredmorbius/comments/22k71x/us_navy_... There's also work by some (including a recent video by Amory Lovins) suggesting that there are relatively modest requirements for dispatchable generation, though I suspect those are a tad optimistic. http://www.engineering.com/ElectronicsDesign/ElectronicsDesignArticles/ArticleID/8272/Is-Storage-Necessary-for-Renewable-Energy.aspx?ENGCOM= http://www.engineering.com/ElectronicsDesign/ElectronicsDesi... https://www.youtube.com/watch?v=MsgrahFln0s https://www.youtube.com/watch?v=MsgrahFln0s

dredmorbius 12y ago

NB: source of that land use chart: http://www.lincolninst.edu/pubs/2036_Alternative-Energy-Sources-and-Land-Use http://www.lincolninst.edu/pubs/2036_Alternative-Energy-Sour... http://newenergyandfuel.com/http:/newenergyandfuel/com/2010/06/08/how-to-use-the-land/landuseforenergy-clintonandrews/ http://newenergyandfuel.com/http:/newenergyandfuel/com/2010/... http://www.cnet.com/news/figuring-land-use-into-renewable-energy-equation/ http://www.cnet.com/news/figuring-land-use-into-renewable-en...