EAST fusion reactor sustains plasma at over 50M Kelvin for 102 seconds

[Spaceception]

This is huge!

http://www.popsci.com/chinas-experimental-fusion-reactor-hits-major-milestone

One step closer to fusion energy for all

 

 

Edited November 12, 2016 by Spaceception

[Bill Phil]

FU!

SION!

HA!

The biggest issue with fusion is keeping the reaction going. Progress is always welcome.

[Scotius]

Incredible Is it possible that great breakthrough is actually just around the corner this time? Cheap (eventually), safe and clean energy for all?

[Spaceception]

24 minutes ago, Scotius said:

Incredible Is it possible that great breakthrough is actually just around the corner this time? Cheap (eventually), safe and clean energy for all?

I sure hope so, perhaps before 2020, we could have limitless energy.

102 seconds is a HUGE milestone, I expect the dominoes to fall shortly

Edited November 12, 2016 by Spaceception

[Nuke]

we got a lot of organizations claiming they will have breakeven fusion by 2020. almost none of them are using tokamaks. the chinese didnt specify their time table, so im calling this just another tokamak.

[kerbiloid]

We can clearly see a correlation. The greater is progress in KSPI-E mod development, the faster they develop thermonuke reactors IRL. Voodoo works.

[cantab]

It's great to get the plasma controlled, but really just a stepping stone. The goal is net power and that still seems some way off.

I'm also sceptical that fusion power will meet the hype. It still has radiation problems, using tritium fuel and emitting neutrons that turn the reactor casing radioactive itself, which means decommissioning the first fusion plants will be just as problematic as decommissioning fission plants. (And aneutronic fusion is even further off). It's still going to be costly to research, develop, build, and maintain fusion plants. I don't know how rapidly fusion plants will be able to change their output, and you need some rapid-response power generation. Perhaps I'm just "Once bitten, twice shy", because nuclear fission power had all the same hype in the early days and over time its flaws have become very apparent.

[SargeRho]

Not quite. The reactor parts become low-level radioactive. You don't get any high level waste from Fusion reactors.

The Neutrons are also used to breed more Tritium fuel, via lithium blankets around the reactor chamber.

 

[Elthy]

As i understood it the radioactive parts of a deocommissioned fusion reactor would be dangerous for a few centurys, not millions of years. This somewhat managable, at least humanity has shown it can build things lasting that long.

[hms_warrior]

On 12.11.2016 at 9:35 PM, Scotius said:

 Cheap (eventually), safe and clean energy for all?

You mean solar cells?

Don't get me wrong fusion is awesome specialy for things in space, submarines, big transport ships everything where you need a independent, 100% uptime, high powerdensity source AND have tonns of money to spend....but fur pure everyday power-generation, fusionreactors will be super expansive to produce and maintain....while solarcells on rooftops are getting cheaper and more powerfull every day.

[Streetwind]

3 hours ago, hms_warrior said:

You mean solar cells?

Don't get me wrong fusion is awesome specialy for things in space, submarines, big transport ships everything where you need a independent, 100% uptime, high powerdensity source AND have tonns of money to spend....but fur pure everyday power-generation, fusionreactors will be super expansive to produce and maintain....while solarcells on rooftops are getting cheaper and more powerfull every day.

^--- This.

Solar had an absurd run these recent years, more so than most people realize. 85% of the world's total solar power capacity has been installed in the last five years. Between January 2015 and May 2016 - that's sixteen months - the cost for new utility-scale solar installations dropped by 50%. Then, five months later in September, it was down another 25%. In 2015, 40% of all new power production equipment installed in the United States was solar... in Q1 2016, it went up to 64%. This summer, a massive solar power plant has been proposed in Nevada that, once built, could sell electricity at less than 3 cents / kWh with optimistic assumptions... and even if that is too optimistic, the average electricity price in the area is around 12 cents / kWh. It's hard to imagine that it won't at least match it, and it most likely will beat it.

It's really going to be very, very cheap going forward, and especially when combined with wind and battery storage, it'll effortlessly serve the majority of humanity's power needs for the foreseeable future.

Fusion meanwhile has its work cut out for it. Recent estimates say that in order to match the cost of non-renewable energy production (mainly coal), a fusion reactor will need a power factor (ratio of power output vs. power input) of greater than 20. To put this into perspective: to this day, no sustained fusion event has had a power factor greater than 1. There was one experiment that achieved enough power output for the reaction to keep itself going... but it happened in an instantaneous blast, in a special reaction chamber unsuited for continuous operation, using a type of fuel that cannot be supplied at runtime. So that doesn't count. And neither do fusion bombs (which admittedly do get large power factors). Even the Chinese reactor this news talked about only posted a high temperature endurance record - it didn't exceed power factor 1 and produced no power.

In fact, the "producing power" part is another unsolved thing. Right now, scientists are still trying to even get a net energy positive reaction going... but once they have it, they still need to tackle the problem of actually extracting that energy from the reaction. Only once that has successfully been implemented can you hope to build a working power plant. And for the time being, only theoretical ideas exist for this. Nothing has been built or tested.

And along now comes solar power, advertising costs of a quarter of conventional fossil fuels. Now the fusion reactor needs a power factor of 80 just to be competitive - with the solar power of today. Solar power isn't done yet; we're in the middle of a continuing downwards trend. Ten years down the line, cost will be at a fraction of what it is today. And fusion reactors still won't be producing power - heck, we're lucky if the ITER research installation even starts its comissioning phase by then.

 

IMHO, fusion power at utility scale is dead before it even came to be. Renewables can already satisfy our power needs at a fraction of the cost. There may be interesting applications for fusion, for instance if we succeed in building a lightweight and efficient spacecraft power source from it, but I don't see it ever become commercially viable on Earth at any point in what future we can realistically foresee.

Edited November 14, 2016 by Streetwind

[kunok]

The big interest of the industry in fusion reactor is that they will have the big installations in their power, whereas the solar installations can perfectly been distributed between the consumers, being able to be self-producers of the energy.

 

What is interesting for space enthusiast like us, is that a propulsion fusion device doesn't need at all to contend the energy or to keep the reaction going, only to be able to focus it, you can think of it more like a engine with an energy amplifier than a proper generator.

[magnemoe]

 

15 hours ago, cantab said:

It's great to get the plasma controlled, but really just a stepping stone. The goal is net power and that still seems some way off.

I'm also sceptical that fusion power will meet the hype. It still has radiation problems, using tritium fuel and emitting neutrons that turn the reactor casing radioactive itself, which means decommissioning the first fusion plants will be just as problematic as decommissioning fission plants. (And aneutronic fusion is even further off). It's still going to be costly to research, develop, build, and maintain fusion plants. I don't know how rapidly fusion plants will be able to change their output, and you need some rapid-response power generation. Perhaps I'm just "Once bitten, twice shy", because nuclear fission power had all the same hype in the early days and over time its flaws have become very apparent.

You get radiation, however you can contain most of it in shielding who can even use it to make tritium or other isotopes. 
It will only happen then neutrons generated by fusion hit stuff making it much more contained than fission reactors.
Radiation Its a major issue for an research system who you want to redesign multiple times, not an major issue for an power reactor where you just swap out some parts.

The tokamak reactors is very hard to design but it would work if the plasma density/ temperature is high enough. 
You have various other designs is unknown if works but if they do they should be possible to make into an operational power plant faster as they are smaller and less technical complex. Smaller also make them useful for other uses than major power plants. 

[wumpus]

On 11/13/2016 at 5:41 PM, cantab said:

It's great to get the plasma controlled, but really just a stepping stone. The goal is net power and that still seems some way off.

I'm also sceptical that fusion power will meet the hype. It still has radiation problems, using tritium fuel and emitting neutrons that turn the reactor casing radioactive itself, which means decommissioning the first fusion plants will be just as problematic as decommissioning fission plants. (And aneutronic fusion is even further off). It's still going to be costly to research, develop, build, and maintain fusion plants. I don't know how rapidly fusion plants will be able to change their output, and you need some rapid-response power generation. Perhaps I'm just "Once bitten, twice shy", because nuclear fission power had all the same hype in the early days and over time its flaws have become very apparent.

I've been skeptical of the hype as well, and also wondering why we haven't been advancing with fission (which has the terribly unsexy issue of actually working).  If anything, I would expect that global warming would make us step back and not just question burning fossil fuels, but also the very concept that "the solution to pollution is dilution".  We've come to understand that plenty of hazardous materials simply shouldn't be created (bioaccumulative materials have a nasty way of undoing dilution).  And even with CO₂ we find that we've managed to overload the planet with an already naturally occurring molecule.  Perhaps simply concentrating the waste and sanely storing it (pretty much unlike current US policy) would be better (contrast littering with pre-recycling landfill practices).

Of course, it looks like fission tech has been ignored for so long that solar and other tech has caught up and surpassed it (at least new PV panels are cheaper than paying for the capital of existing nuclear plants in the US).  I also have to wonder about the regulations that strangled the US nuclear industry.  Some of that came from people conflating nuclear bombs with peaceful nukes, but I can't help but wonder if the industry executives were afraid that electrical power would get "to cheap to meter" and made sure that their "cost plus" pricing schemes made sure costs stayed high.

[kunok]

@wumpus fission tech hasn't been ignored nor regulated to death, it just that is very expensive, research is very expensive, resource extraction is problematic and contaminating, refinement of the nuclear fuel is very expensive, safeguarding it and transporting is very expensive, dealing with residues is very expensive...

The only real pro of nuclear energy (currently in fission and probably in fusion) is energy density, that's only good for transport not for fixed installations. I would expect to be a good idea for boats and spacecraft, and maybe even aircraft if is cheap, safe and light enough, but I won't expect it to never be cheap enough.

[wumpus]

6 hours ago, kunok said:

@wumpus fission tech hasn't been ignored nor regulated to death, it just that is very expensive, research is very expensive, resource extraction is problematic and contaminating, refinement of the nuclear fuel is very expensive, safeguarding it and transporting is very expensive, dealing with residues is very expensive...

The only real pro of nuclear energy (currently in fission and probably in fusion) is energy density, that's only good for transport not for fixed installations. I would expect to be a good idea for boats and spacecraft, and maybe even aircraft if is cheap, safe and light enough, but I won't expect it to never be cheap enough.

Current US regulations:

-No processing of spent fuel rods

-No breeder reactors

US regulations when were still building the silly things:

-All reactors shall be custom built (no reuse of plans)

-All reactors shall meet any current regulation when they first produce power (not sure about they key time, but it was post construction).  Expect plenty of expensive back fitting to fit any changes.

While I'm sure that there were some silly ideas about other utilities at the time, they didn't stop everything in its tracks like nuclear power.  The other catch is that energy density implies that you don't have to basically tear all the mountains off of West Virginia and tear it down to bedrock to get out the coal.  And had Carter* not banned spent fuel reprocessing, you barely would have any mining costs (both money and lives) at all.

* I'd love to know why Jimmy Carter did this.  Of all the various politicians and bureaucrats who regulate things, this was an actual expert making the decision.  I'd really like to know the reasoning.

PS.  Why can't I force this to single space?  CR+LF doesn't have to mean CR+LF+LF!  Yet another thing broken with the new broken forum software.

[kunok]

50 minutes ago, wumpus said:

-No processing of spent fuel rods

-No breeder reactors

We are derailing the thread, but both of this are even worse in the refinement process than the original ore, with more dangerous materials, worse security problems, and IIRC correctly would need more stages of refinement (not sure about the wording in english). Mining is the cheap part in terms of money.

I don't know USA regulations, but there are other countries that aren't USA, without almost any regulations that aren't making new nuclear plants everywhere. Nuclear energy is expensive, very very expensive. It never was the clean and cheap energy as expected.

And com'on don't compare nuclear power with coal, that's a false dichotomy, is not the only alternative.

[problemecium]

2 hours ago, wumpus said:

PS.  Why can't I force this to single space?  CR+LF doesn't have to mean CR+LF+LF!  Yet another thing broken with the new broken forum software.

I feel your pain. For now try hitting Shift+Enter.
See? Mind you it's a bit finicky though; if you hit Enter and then change your mind and backspace to try again, it'll try to double-space anyway so you have to do it twice.
At least it can be made to work the way we want... xD

[wumpus]

5 hours ago, kunok said:

And com'on don't compare nuclear power with coal, that's a false dichotomy, is not the only alternative.

They are closer than they seem.  One of the main points of nuclear is that all the costs are concentrated in the plant, not the fuel so you run it 24/7.  Coal traditionally was also in this range (with big plants that ran 24/7 and took days to turn on and off).  I'd be surprised if power companies can finagle gas & similar plants to operate during the night, especially if they need the wattage of the old coal plants during the summer.  Neither compete with solar or wind *at* *all* (gas does).

Also right now non-coal production is deliberately strange.  Once Saudis stop their oil war, I suspect that the price of natural gas (& oil, not sure how much electricity comes from oil, but I suspect it makes sense now) will go back above coal.  And coal will either contend with nuclear for coal from base production or get kicked to the curb for its nasty emission.

[78stonewobble]

On ‎14‎-‎11‎-‎2016 at 0:24 PM, Streetwind said:

^--- This.

Solar had an absurd run these recent years, more so than most people realize. 85% of the world's total solar power capacity has been installed in the last five years. Between January 2015 and May 2016 - that's sixteen months - the cost for new utility-scale solar installations dropped by 50%. Then, five months later in September, it was down another 25%. In 2015, 40% of all new power production equipment installed in the United States was solar... in Q1 2016, it went up to 64%. This summer, a massive solar power plant has been proposed in Nevada that, once built, could sell electricity at less than 3 cents / kWh with optimistic assumptions... and even if that is too optimistic, the average electricity price in the area is around 12 cents / kWh. It's hard to imagine that it won't at least match it, and it most likely will beat it.

It's really going to be very, very cheap going forward, and especially when combined with wind and battery storage, it'll effortlessly serve the majority of humanity's power needs for the foreseeable future.

Fusion meanwhile has its work cut out for it. Recent estimates say that in order to match the cost of non-renewable energy production (mainly coal), a fusion reactor will need a power factor (ratio of power output vs. power input) of greater than 20. To put this into perspective: to this day, no sustained fusion event has had a power factor greater than 1. There was one experiment that achieved enough power output for the reaction to keep itself going... but it happened in an instantaneous blast, in a special reaction chamber unsuited for continuous operation, using a type of fuel that cannot be supplied at runtime. So that doesn't count. And neither do fusion bombs (which admittedly do get large power factors). Even the Chinese reactor this news talked about only posted a high temperature endurance record - it didn't exceed power factor 1 and produced no power.

In fact, the "producing power" part is another unsolved thing. Right now, scientists are still trying to even get a net energy positive reaction going... but once they have it, they still need to tackle the problem of actually extracting that energy from the reaction. Only once that has successfully been implemented can you hope to build a working power plant. And for the time being, only theoretical ideas exist for this. Nothing has been built or tested.

And along now comes solar power, advertising costs of a quarter of conventional fossil fuels. Now the fusion reactor needs a power factor of 80 just to be competitive - with the solar power of today. Solar power isn't done yet; we're in the middle of a continuing downwards trend. Ten years down the line, cost will be at a fraction of what it is today. And fusion reactors still won't be producing power - heck, we're lucky if the ITER research installation even starts its comissioning phase by then.

 

IMHO, fusion power at utility scale is dead before it even came to be. Renewables can already satisfy our power needs at a fraction of the cost. There may be interesting applications for fusion, for instance if we succeed in building a lightweight and efficient spacecraft power source from it, but I don't see it ever become commercially viable on Earth at any point in what future we can realistically foresee.

So what is the enviromental footprint of building, maintaining and safely getting rid of the necessary solar power generation and energy storage equipment to cover the worlds energy usage (155,505 terawatt-hours in 2012) and considering transmission losses and that our heating will have to be electrical?

Specifically...

How many square kilometers of solar gathering area?

How many tonnes of silicon, cadmium, telluride, copper, indium, gallium, selenide and so forth will be needed?

How much water needs to be pumped to what height, with associated risks?

How much salt will be needed for molten salt storage and how long will it take to produce it at current rates?

How much hydrogen in how many tanks of such and such a size and what risks does that entail?

What is the co2 and other enviromental concerns of all the above?

...

And how does solar then stack up against nuclear fission and/or fusion?

Without answering those, we can't know whether solar or wind  is the way forward or if it's just repeating the mistakes of the past...

So do you have those answers?

Or did you just look at the kWh cost?

 

[magnemoe]

6 hours ago, wumpus said:

Current US regulations:

-No processing of spent fuel rods

-No breeder reactors

US regulations when were still building the silly things:

-All reactors shall be custom built (no reuse of plans)

-All reactors shall meet any current regulation when they first produce power (not sure about they key time, but it was post construction).  Expect plenty of expensive back fitting to fit any changes.

While I'm sure that there were some silly ideas about other utilities at the time, they didn't stop everything in its tracks like nuclear power.  The other catch is that energy density implies that you don't have to basically tear all the mountains off of West Virginia and tear it down to bedrock to get out the coal.  And had Carter* not banned spent fuel reprocessing, you barely would have any mining costs (both money and lives) at all.

* I'd love to know why Jimmy Carter did this.  Of all the various politicians and bureaucrats who regulate things, this was an actual expert making the decision.  I'd really like to know the reasoning.

PS.  Why can't I force this to single space?  CR+LF doesn't have to mean CR+LF+LF!  Yet another thing broken with the new broken forum software.

I think fuel reproduction was stopped as an symbolic gesture, no reproduction= no plutonium for nuclear bombs. Symbolic as the US had an huge stockpile of plutonium and you don't use plutonium from power reactors in bombs anyway, the isotopes are wrong. 
It might be to limit nuclear power but you simple mine more, fuel cost is an minor cost for nuclear plants. 

All plants have to be custom build is even more stupid. It reduces safety, with an common design you will improve all plants if you find an safety issue in one of them. Look on how this works on planes. 
It also increases cost a lot, this is the main purpose as it makes it harder to build nuclear plants.

Lots of regulations makes no sense at all: they are created by an political purpose, then the other side comes to power but are often unable to repel the regulation, lots of times they don't want either so they weaken it a lot. Continue this and you get an illogical patchwork who might be counter productive.  
The SUV bypassed the fuel use restriction on standard cars since they was trucks and pretty much became the standard car. 

 

[HebaruSan]

On 11/12/2016 at 8:15 PM, Nuke said:

we got a lot of organizations claiming they will have breakeven fusion by 2020. almost none of them are using tokamaks. the chinese didnt specify their time table, so im calling this just another tokamak.

Yup, OP's link says, "EAST is a tokamak, a doughnut shaped device originally designed by the Soviets." (paragraph #3)

[Streetwind]

7 hours ago, 78stonewobble said:

So what is the enviromental footprint of building, maintaining and safely getting rid of the necessary solar power generation and energy storage equipment to cover the worlds energy usage (155,505 terawatt-hours in 2012) and considering transmission losses and that our heating will have to be electrical?

Specifically...

How many square kilometers of solar gathering area?

How many tonnes of silicon, cadmium, telluride, copper, indium, gallium, selenide and so forth will be needed?

How much water needs to be pumped to what height, with associated risks?

How much salt will be needed for molten salt storage and how long will it take to produce it at current rates?

How much hydrogen in how many tanks of such and such a size and what risks does that entail?

What is the co2 and other enviromental concerns of all the above?

...

And how does solar then stack up against nuclear fission and/or fusion?

Without answering those, we can't know whether solar or wind  is the way forward or if it's just repeating the mistakes of the past...

So do you have those answers?

Or did you just look at the kWh cost?

 

Hey now. Discussions can easily be held in a less dismissive tone of voice, if you're actually interested in the answers to the questions you posed.

1.) Area required: a cursory look at Google reveals estimates that speak of less than 1% of Earth's surface for the projected energy needs of 2030, using nothing but 100% solar on 100% dedicated land. This does not take into account the ability for solar installations to share space with other things (such as buildings, by being mounted on roofs). Additionally, solar installations can occupy low-value, 'useless' space, like deserts, abandoned mining sites, or safety buffer zones around industry or transportation corridors. Also does not take into account the mixing-in of other renewable energy sources, like wind (which can share space with agricultural areas or be built offshore). Current solar technology averages around 5 acres per megawatt, with prime locations needing significantly less, and the trend going downwards as technology improves. The average residential house in most countries already has enough roof area to run itself off of solar power with no additional external input required, if combined with a small power storage solution. Utility scale installations will continue to be necessary for apartment and office buildings, skyscrapers, and industry, but they will have to foot a reduced share of the total power needs, and thus require less area.

2.) Raw material consumption: There's probably no person on Earth who can answer this question, due to the amount of variables involved. It depends on which technology by which manufacturer is used in which amounts, in which areas, in which countries, bound by which regulations. However, most of the more exotic and less abundant materials are reasonably pricy, so there's a strong incentive to recycle old panels. This will only increase if it turns out that PV production puts a serious strain on the supply. Meanwhile, concentrating solar thermal doesn't require these exotic materials at all.

3.) Water consumption: I've found this table comparing water withdrawal and consumption per MWh for typical power generation options in the United States. Concentrating solar thermal plants are roughly on par with existing fossil fuel and fission plants... which should surprise no one, since the water is used for the exact same purposes (producing steam and cooling turbines and generators). Gas turbines use less than the others, because they turn generators directly, without the need of an interposed steam turbine system. Photovoltaic systems aren't on that table because they use a lot less. Like, more than ten thousand times less. Washing the entire farm's panels twice a month probably takes less water than a conventional plant consumes in an hour (broad guess).

4.) I have no idea how much of salt XYZ is being produced per year. I would be surprised if it was an issue, though, because producing salt literally involves mixing a solution, evaporating it, and scooping up the solid remains with a large shovel. Maintaining purity makes the whole process more elaborate, but not inherently more difficult to scale. Typical thermal storage salt is a mixture of sodium, potassium, and calcium nitrates. These are bog standard chemical resources, which are churned out worldwide in gigantic amounts because they are base ingredients for uncountable processes and chemical compounds. You'll find them in any high school's chemistry classroom, even. Their constituent elements are dirt cheap and vastly abundant. After a molten salt power plant is decomissioned, the salt can be effortlessly recycled.

5.) What hydrogen? I said nothing about hydrogen. I suppose it's one option of buffering power for use at night, but it's not the only option. We don't know yet which solution is the most practicable at large scale and in the long term, because we've not yet migrated away from conventional base load power plants. For what it's worth, though: storing large amounts of hydrogen safely is a solved problem. Whether it makes economical sense, we'll see.

6.) Lifecycle global warming emissions of power production technologies seems to be a contentious and difficult topic, if Google is any indication. For example, I've found anywhere from 20 to 50 grams CO2-equivalent for solar, anywhere from 12 to 60 grams for nuclear fission (not counting radioactive waste), anywhere from 440g to 490g for natural gas (at least this one seems to be fairly agreed upon), anywhere from 820g to 1130g for coal, and anywhere from 4g to >100g for hydroelectric (seems especially variable depending on implementation). Winner is actually wind power, with anywhere from 9 to 12 grams. No numbers for fusion, because it's impossible to calculate at this point - we don't yet know how a hypothetical fusion power plant would have to look for a given power output, nor the lifecycles of its various constituent elements.

Edited November 16, 2016 by Streetwind

[78stonewobble]

27 minutes ago, Streetwind said:

Hey now. Discussions can easily be held in a less dismissive tone of voice, if you're actually interested in the answers to the questions you posed.

1.) Area required: a cursory look at Google reveals estimates that speak of less than 1% of Earth's surface for the projected energy needs of 2030, using nothing but 100% solar on 100% dedicated land. This does not take into account the ability for solar installations to share space with other things (such as buildings, by being mounted on roofs). Additionally, solar installations can occupy low-value, 'useless' space, like deserts, abandoned mining sites, or safety buffer zones around industry or transportation corridors. Also does not take into account the mixing-in of other renewable energy sources, like wind (which can share space with agricultural areas or be built offshore). Current solar technology averages around 5 acres per megawatt, with prime locations needing significantly less, and the trend going downwards as technology improves. The average residential house in most countries already has enough roof area to run itself off of solar power with no additional external input required, if combined with a small power storage solution. Utility scale installations will continue to be necessary for apartment and office buildings, skyscrapers, and industry, but they will have to foot a reduced share of the total power needs, and thus require less area.

2.) Raw material consumption: There's probably no person on Earth who can answer this question, due to the amount of variables involved. It depends on which technology by which manufacturer is used in which amounts, in which areas, in which countries, bound by which regulations. However, most of the more exotic and less abundant materials are reasonably pricy, so there's a strong incentive to recycle old panels. This will only increase if it turns out that PV production puts a serious strain on the supply. Meanwhile, concentrating solar thermal doesn't require these exotic materials at all.

3.) Water consumption: I've found this table comparing water withdrawal and consumption per MWh for typical power generation options in the United States. Concentrating solar thermal plants are roughly on par with existing fossil fuel and fission plants... which should surprise no one, since the water is used for the exact same purposes (producing steam and cooling turbines and generators). Gas turbines use less than the others, because they turn generators directly, without the need of an interposed steam turbine system. Photovoltaic systems aren't on that table because they use a lot less. Like, more than ten thousand times less. Washing the entire farm's panels twice a month probably takes less water than a conventional plant consumes in an hour (broad guess).

4.) I have no idea how much of salt XYZ is being produced per year. I would be surprised if it was an issue, though, because producing salt literally involves mixing a solution, evaporating it, and scooping up the solid remains with a large shovel. Maintaining purity makes the whole process more elaborate, but not inherently more difficult to scale. Typical thermal storage salt is a mixture of sodium, potassium, and calcium nitrates. These are bog standard chemical resources, which are churned out worldwide in gigantic amounts because they are base ingredients for uncountable processes and chemical compounds. You'll find them in any high school's chemistry classroom, even. Their constituent elements are dirt cheap and vastly abundant. After a molten salt power plant is decomissioned, the salt can be effortlessly recycled.

5.) What hydrogen? I said nothing about hydrogen. I suppose it's one option of buffering power for use at night, but it's not the only option. We don't know yet which solution is the most practicable at large scale and in the long term, because we've not yet migrated away from conventional base load power plants. For what it's worth, though: storing large amounts of hydrogen safely is a solved problem. Whether it makes economical sense, we'll see.

6.) Lifecycle global warming emissions of power production technologies seems to be a contentious and difficult topic, if Google is any indication. For example, I've found anywhere from 20 to 50 grams CO2-equivalent for solar, anywhere from 12 to 60 grams for nuclear fission (not counting radioactive waste), anywhere from 440g to 490g for natural gas (at least this one seems to be fairly agreed upon), anywhere from 820g to 1130g for coal, and anywhere from 4g to >100g for hydroelectric (seems especially variable depending on implementation). Winner is actually wind power, with anywhere from 9 to 12 grams. No numbers for fusion, because it's impossible to calculate at this point - we don't yet know how a hypothetical fusion power plant would have to look for a given power output, nor the lifecycles of its various constituent elements.

Sorry, if the tone was somewhat dismissive... but it doesn't seem like many actually looks at these things.

1. If my math is correct... Using the Topaz Solar Farm, as a point of comparison, you would need 141,368 plants of the same size to match the worlds energy supply in 2012. 1,272,313,636,363 individual solar panels that themselves take up 945,614 square kilometers or roughly the size of Tanzania. The weight of the solarpanels and thus the materials necessary to construct them would be... 15,870,573,350 tonnes. For comparison of that number the world wide plastics production was 280,000,000 tonnes in 2011, so if the solar panels were all plastic it would take 56,6 years to produce them, while leaving the world without plastic for anything else.

2. Take the different panels composition and multiply by whatever it would take to cover the worlds energy supply with those solar panels.

3. As a point of comparison the Andasol powerplant in spain vaporizes 2,610,000 cubik meters a year of water. To match the worlds energy supply in 2012 via similar methods would vaporize 819,935,454,545 cubic meters a year. Which is equivalent to 124,402 amazon rivers.

4. Again using the Andasol 1 powerplant for comparison it uses 28,500 tons of molten salt for energy storage. To scale the plant to match the worlds energy supply in 2012 would require 28,049,952,531 tonnes of salts, which are 60 percent sodium nitrate (16,829,971,518 tonnes) and 40 percent potassium nitrate (11,219,981,012 tonnes).

PS: Depends on how this is supposed to be understood "The storage tank consists of two, 14-meter high tanks with a diameter of 36 meters and a capacity of 28,500 tons of molten salt." ... If the capacity is for 1 tank rather than both, we would need to double the above numbers.

I don't know about sodium nitrate production, but afaik. potassium nitrate comes from potash, whose production was 37,620,000 tonnes in 2011. It can't all be potassium nitrate, but even if all production went to solar energy storage it would take 298 years to produce enough, but the lack of fertilizers would probably solve the energy problems in a quite different way.

5. Define safely and define large scale? How much hydrogen storage is required for the 104,426 TWh consumption and 155,505 TWh supply?

6. Indeed... And I genuinely don't think they account for eg. just the massive square footage area of eg. solar panels and what that implies for distribution and maintenance of them.

...

I will leave you with this:

And for comparison we would need "just" 3,456 nuclear powerplants like Bruce power station to match the total world wide power supply of 2012.  

 

 

[Elthy]

If you want to supply several billions of people with energy you will allways have huge numbers...

Dont forget that Uranium is not a renewable resource, so you would run out of it quite fast when using it to power the whole earth. And those powerplants consist of thousands of tons material, too.

I wouldnt consider 1 million km^2 much, we use 1/3 of the earth surface for growing food.

Edited November 16, 2016 by Elthy