FYI,
New Scientist
http://www.newscientist.com/article/dn16550-why-sustainable-power-is-
unsustainable.html
: Renewable energy needs to become a lot more renewable a theme
: that emerged at the Financial Times Energy Conference in London
: this week.
: Supratik Guha of IBM told the conference that sales of silicon
: solar cells are booming, with 2008 being the first year that the
: silicon wafers for solar cells outstripped those used for
: microelectronic devices.
: But although silicon is the most abundant element in the Earth's
: crust after oxygen, it makes relatively inefficient cells that
: struggle to compete with electricity generated from fossil fuels.
: And the most advanced solar-cell technologies rely on much rarer
: materials than silicon.
: Rare metal
: The efficiency of solar cells is measured as a percentage of light
: energy they convert to electricity. Silicon solar cells finally
: reached 25% in late December. But multi-junction solar cells can
: achieve efficiencies greater than 40%.
: Although touted as the future of solar power, those and most other
: multiple-junction cells owe their performance to the rare metal
: indium, which is far from abundant. There are fewer than
: 10 indium-containing minerals, and none present in significant
: deposits in total the metal accounts for a paltry 0.25 parts per
: million of the Earth's crust.
: Most of the rare and expensive element is used to manufacture LCD
: screens, an industry that has driven indium prices to $1000 per
: kilogram in recent years. Estimates that did not factor in an
: explosion in indium-containing solar panels reckon we have only a
: 10 year supply of it left.
: If power from the Sun is to become a major source of electricity,
: solar panels would have to cover huge areas, making an alternative
: to indium essential.
: Precious platinum
: The dream of the hydrogen economy faces similar challenges, said
: Paul Adcock of UK firm Intelligent Energy.
: A cheap way to generate hydrogen has so far proved elusive. New
: approaches, such as using bacterial enzymes to "split" water, have
: a long way to go before they are commercially viable.
: So far, fuel cells are still the most effective way to turn the gas
: into electricity. But these mostly rely on expensive platinum to
: catalyse the reaction.
: The trouble is, platinum makes indium appear super-abundant. It is
: present in the Earth's crust at just 0.003 parts per billion and is
: priced in $ per gram, not per kilogram. Estimates say that, if the
: 500 million vehicles in use today were fitted with fuel cells, all
: the world's platinum would be exhausted within 15 years.
: Unfortunately platinum-free fuel cells are still a long way from
: the test track. A nickel-catalysed fuel cell developed at Wuhan
: University, China, has a maximum output only around 10% of that a
: platinum catalyst can offer.
: A new approach announced yesterday demonstrates that carbon
: nanotubes could be more effective, as well as cheaper, than
: platinum. But again it will be many years before platinum-free fuel
: cells become a commercial prospect.
: Renewable energy technologies remain the great hope for the future,
: and are guaranteed research funds in the short term. But unless a
: second generation of sustainable energy ideas based on truly
: sustainable resources is established, the renewable light could be
: in danger of dimming.
Mark Reiff
We could always go to thermal capture of solar energy to drive turbines, though I've no hard data on how efficient that is, it is probably no more than 40%.
The solar cell trend is to capture multiple frequencies of radiation - the area under the curves, not just a single frequency.
As efficiencies increase, the solar cells will be recycled. However, the market begins with those early adopters in corporations and homes to create a large stable market to provide the benefits of mass manufacturing and multiple competitors to drive the price down.
As the market goes mainstream, then the early adopters will adopt when it makes economic sense and recycle their solar cells. In the recycle process, the precious metals will be recycled, and new processes inserted.
Environmental activists have to figure out the economics and actually promote mining of minerals to build a sustainable solar cell market. The demand may make it too expensive, and then a crash will make it desireable to buy, but not to mine or manufacture, or even recycle.
And if you like solar cells, you may want to look at wind generators. After all, they respond 24 x 7 to wind and not just the sunrise to sunset curve. Sustainability there is in the new technology of switched electric generators which will convert wind of all velocities. Engineering goal is 200 mph, about that of a small airplane.
Finally, the environment cry for recycle and renewables has given way to sustainable. Insulation is the ultimate sustainable technology.Moving all people-occupied building structures to a higher level would go a long way to reducing the demand for energy allowing the dynamic power, light and heat energy technologies a chance to get more efficient and economic.
David
Gary 7
Nuclear power is also "sustainable."
FYI,
"Why Sustainable Power is Unsustainable"
New Scientist
http://www.newscientist.com/article/dn16550-why-sustainable-power-is-
unsustainable.html
: Renewable energy needs to become a lot more renewable a theme
: that emerged at the Financial Times Energy Conference in London
: this week.
: Supratik Guha of IBM told the conference that sales of silicon
: solar cells are booming, with 2008 being the first year that the
: silicon wafers for solar cells outstripped those used for
: microelectronic devices.
: But although silicon is the most abundant element in the Earth's
: crust after oxygen, it makes relatively inefficient cells that
: struggle to compete with electricity generated from fossil fuels.
: And the most advanced solar-cell technologies rely on much rarer
: materials than silicon.
: Rare metal
: The efficiency of solar cells is measured as a percentage of light
: energy they convert to electricity. Silicon solar cells finally
: reached 25% in late December. But multi-junction solar cells can
: achieve efficiencies greater than 40%.
: Although touted as the future of solar power, those and most other
: multiple-junction cells owe their performance to the rare metal
: indium, which is far from abundant. There are fewer than
: 10 indium-containing minerals, and none present in significant
: deposits in total the metal accounts for a paltry 0.25 parts per
: million of the Earth's crust.
: Most of the rare and expensive element is used to manufacture LCD
: screens, an industry that has driven indium prices to $1000 per
: kilogram in recent years. Estimates that did not factor in an
: explosion in indium-containing solar panels reckon we have only a
: 10 year supply of it left.
: If power from the Sun is to become a major source of electricity,
: solar panels would have to cover huge areas, making an alternative
: to indium essential.
: Precious platinum
: The dream of the hydrogen economy faces similar challenges, said
: Paul Adcock of UK firm Intelligent Energy.
: A cheap way to generate hydrogen has so far proved elusive. New
: approaches, such as using bacterial enzymes to "split" water, have
: a long way to go before they are commercially viable.
: So far, fuel cells are still the most effective way to turn the gas
: into electricity. But these mostly rely on expensive platinum to
: catalyse the reaction.
: The trouble is, platinum makes indium appear super-abundant. It is
: present in the Earth's crust at just 0.003 parts per billion and is
: priced in $ per gram, not per kilogram. Estimates say that, if the
: 500 million vehicles in use today were fitted with fuel cells, all
: the world's platinum would be exhausted within 15 years.
: Unfortunately platinum-free fuel cells are still a long way from
: the test track. A nickel-catalysed fuel cell developed at Wuhan
: University, China, has a maximum output only around 10% of that a
: platinum catalyst can offer.
: A new approach announced yesterday demonstrates that carbon
: nanotubes could be more effective, as well as cheaper, than
: platinum. But again it will be many years before platinum-free fuel
: cells become a commercial prospect.
: Renewable energy technologies remain the great hope for the future,
: and are guaranteed research funds in the short term. But unless a
: second generation of sustainable energy ideas based on truly
: sustainable resources is established, the renewable light could be
: in danger of dimming.
Mark Reiff
I can't help but note that a silicon PV in HEO will produce
better than twice the electricity as an indium PV of the
same size here on Earth.
fuel cells, etc.) aren't available RIGHT NOW doesn't matter
a whole lot when you consider that we can't instantly
switch from coal to anything else anyway. It's going to
take a while to make that switch, and during that while, we
can improve our fuel cells and the like.
BTW, how common is indium in asteroids? I know that
they're a good source for PGM.
>We could always go to thermal capture of solar
>energy to drive turbines, though I've no hard
>data on how efficient that is, it is probably no more than 40%.
>
>Gary 7
And we currently build jet engines and steam
turbines in numbers close to what would be needed. (Acording to Phil Chapman.)
I have been looking into this considering how to
put a GW/day of new power plants in GEO. Solar
cell production probably can't be ramped up fast enough.
It sure would be easier with extra terrestrial
materials available. A substantial fraction of a
thermal cycle power plant is heat transfer
fluid. Eric Drexler and I came up with a way to
use ground up rock and a low pressure gas as a
pseudo fluid back in the 70s. All we would need
is a vibratory ball mill to make any kind of rock into something valuable.
Keith
That article was not smartly written.
As someone said earlier solar thermal can be the way to go. It has no problem with rare materials.
This is not a technology problem it is a political and economic problem.
Look the problem is the oil and coal lobby with their monopolistic control of this country.
BestRegards,
Pete
,_._,___
> As a country America can build 100 sq. miles of solar
> thermal power plants in the southwest and take care of
> all of America's needs.
10,000 sq. miles.
So we put 1,250 sq. miles (1/8 of 10,000) in orbit, and
there you go. That's 35.36 miles on a side.
It isn't 161 sq. Km, it's a hundred sixty-one Km on a
side: 25,900 sq. Km.
So we put 3237 sq. Km (1/8 of 25,900) in orbit, and
there you go. That's 57 Km on a side.
Shortage of Indium means PV cells could become very expensive, which
might make it more economical to put them into space where they are
continuously illuminated. Putting your expensive PV cells on Earth,
where they are in darkness most of the time, makes them a
non-performing asset (for most of the time), and is bad business practice.
Also demand for Platinum (for fuel cells) will exceed supply causing
the price to sky rocket. Might become economical to go after
Platinum asteroids near Earth.
That article was not smartly written.
As someone said earlier solar thermal can be the way to go. It has no problem with rare materials.
This is not a technology problem it is a political and economic problem.
Look the problem is the oil and coal lobby with their monopolistic control of this country.
Really? And what is America supposed to do at night? Or when clouds cover that 100 miles square?
Michael McNeil
As has been preciously pointed out, the "100 sq miles to provide ALL US energy needs" is in error. It's an area 100 miles ON A SIDE, that's 10,000 sq miles, NOT 100. By my calculation, at current practical conversion efficiencies of 25%(then divide by 2 because we only have 1/2 day of sunlight), even 10,000 sq miles won't do the trick. At best it could only provide 1.3 Terra Watts of generating capacity and that's not even deducting for cloudy/stormy days,,,note the following link, which states we are currently generating 3.9 Terra Watts of electricity, not the 1.3 that might be generated by 10,000 sq miles of solar. 3.9 T-Watts is a far cry from 1.3.
"Total electricity consumption, including both purchases
from electric power producers and on-site
generation, grows from 3,903 billion kilowatthours
in 2007 to 4,902 billion kilowatthours in
2030, increasing at an average annual rate of 1.0"
The above is on page 11 of the PDF,,,
GAry 7
Since you're pointing at my posting, I will note that I said "100 miles square" not 100 sq. miles.
As has been preciously pointed out, the "100 sq miles to provide ALL US energy needs" is in error. It's an area 100 miles ON A SIDE, that's 10,000 sq miles, NOT 100. By my calculation, at current practical conversion efficiencies of 25%(then divide by 2 because we only have 1/2 day of sunlight), even 10,000 sq miles won't do the trick. At best it could only provide 1.3 Terra Watts of generating capacity and that's not even deducting for cloudy/stormy days,,,note the following link, which states we are currently generating 3.9 Terra Watts of electricity, not the 1.3 that might be generated by 10,000 sq miles of solar. 3.9 T-Watts is a far cry from 1.3.
http://www.eia.doe.gov/oiaf/aeo/pdf/earlyrelease.pdf
"Total electricity consumption, including both purchases
from electric power producers and on-site
generation, grows from 3,903 billion kilowatthours
in 2007 to 4,902 billion kilowatthours in
2030, increasing at an average annual rate of 1.0"
The above is on page 11 of the PDF,,,
GAry 7
Michael: Here's a copy from your submittal, which is what I read:
That's from your previous post of: "February 17, 2009 12:12 PM"
I understand we can easily make editing mistakes. It's a very human thing to do,,,
Peace,
Gary 7
Michael: Here's a copy from your submittal, which is what I read:
That's from your previous post of: "February 17, 2009 12:12 PM"
That's quoted text (visibly quoted, at least in many browsers, shown with a sidebar along the left) from the earlier posting by ForDutyAndHumanity IAmSpacebearAICDA astrobear@... to which I was responding. Since it was a quotation, I didn't correct his error there.
My reply, entered below the quoted text, read: "Really? And what is America supposed to do at night? Or when clouds cover that 100 miles square?"
I understand we can easily make editing mistakes. It's a very human thing to do,,,
Agreed (and I make plenty of them, just not right then), however the same is true for reading mistakes.
Best,
Michael
It really doesnt matter who wrote what. What matters is that it is not practical to try to replace this countrys baseload power with earth-based solar panelsbecause of the amount of land that would have to be covered with them, because of the distribution problems created by the maldistribution of sunny areas throughout the U.S., and most of all because of the absence of any solar power a majority of the time, since it gets dark, and it rains. Thats why we need to build solar collector satellites to gather solar power where it is strongest, and where it can be retrieved 24 hours a day: in earth orbit.
That's quoted text (visibly quoted, at least in many browsers, shown with a sidebar along the left) from the earlier posting by ForDutyAndHumanity IAmSpacebearAICDA astrobear@... to which I was responding. Since it was a quotation, I didn't correct his error there.
My reply, entered below the quoted text, read: "Really? And what is America supposed to do at night? Or when clouds cover that 100 miles square?"
I understand we can easily make editing mistakes. It's a very human thing to do,,,
Agreed (and I make plenty of them, just not right then), however the same is true for reading mistakes.
Best,
Michael
While I'm not at all averse to orbiting solar power satellites, as I noted before we don't strictly speaking "need" to build them, because one can also build nuclear power plants -- which are also "sustainable" -- down here on Earth.
It really doesn't matter who wrote what. What matters is that it is not practical to try to replace this country's baseload power with earth-based solar panelsbecause of the amount of land that would have to be covered with them, because of the distribution problems created by the maldistribution of sunny areas throughout the U.S., and most of all because of the absence of any solar power a majority of the time, since it gets dark, and it rains.
That's why we need to build solar collector satellites to gather solar power where it is strongest, and where it can be retrieved 24 hours a day: in earth orbit.
Its not at all clear that we can build a sufficient number of nuclear power plants to replace all of the current non-nuclear baseload power on Earth, as well as all that will be needed in the next 50100 years, because of, among other things, safety considerations and the problems of nuclear waste disposal. The fact that none of the nuclear plants on the drawing board in the U.S. is now under construction underlines those problems. As one who lives near a nuclear plant which recently was forced to shut down because of the corrosion of the reactor lid which endangered the entire community, I am especially conscious of those issues. Politically, I dont believe we can build that number of nuclear plants in the U.S.
It really doesn't matter who wrote what. What matters is that it is not practical to try to replace this country's baseload power with earth-based solar panelsbecause of the amount of land that would have to be covered with them, because of the distribution problems created by the maldistribution of sunny areas throughout the U.S., and most of all because of the absence of any solar power a majority of the time, since it gets dark, and it rains.
That's why we need to build solar collector satellites to gather solar power where it is strongest, and where it can be retrieved 24 hours a day: in earth orbit.
It's not at all clear that we "can" build a sufficient number of nuclear power plants to replace all of the current non-nuclear baseload power on Earth, as well as all that will be needed in the next 50100 years, because of, among other things, safety considerations
Nuclear power plants have an excellent safety record and 90% availability. Newer models that have been and will be designed in the future are even safer, many with an inherent invulnerability to "meltdown."
and the problems of nuclear waste disposal.
The waste problem has been enormously over-hyped. The idea that we must come up with a "solution" to the waste that must work without any human intervention whatsoever (or even looking in to see how things are going) for hundreds of thousands of years is ludicrous and purely an artificial problem. A workable solution in my view would be to simply put all the waste (all the highly radioactive waste generated in the industry's history by all the nuclear plants in the United States -- 20% of the nation's power supply -- would fit within a 250 ft. cube) in one spot and put a guard on it. However, going well beyond that, the waste depository under construction at Yucca Mountain in Nevada appears to be an excellent solution for the time being.
The fact that none of the nuclear plants on the drawing board in the U.S. is now under construction underlines those problems.
It underlines the political problems that the U.S. and other countries have faced due to anti-nuke hystericists, not technical problems.
As one who lives near a nuclear plant which recently was forced to shut down because of the corrosion of the reactor lid which endangered the entire community,
And precisely how much "danger" was the community in, pray tell? Not very much I'd be willing to bet.
I am especially conscious of those issues. Politically, I don't believe we "can" build that number of nuclear plants in the U.S.
On the contrary, all it takes is the will.
Michael McNeil
That makes me feel so much safer. See the attached: In an "attempt to win a $200 million insurance dispute," FirstEnergy publicly reversed course on its responsibility for the near-catastrophe at the Davis-Besse nuclear plant near Toledo, Ohio. "FirstEnergy has abruptly shrugged off the blame it once accepted for repeatedly missing a football-size rust hole growing in the lid of the radioactive, high-pressure reactor," reported The Plain Dealer. "At the time, the utility paid $33.5 million in criminal and civil fines to acknowledge its culpability for failing to stop the corrosion and for misleading government regulators." [3] FirstEnergy then claimed that "corrosion ate through the steel lid so quickly -- in four months, not the previously accepted four years -- that normal biennial inspections couldn't have caught it." The "new version of events" was put forward by Exponent Failure Analysis Associates, a consultant to FirstEnergy. But the consultant's report didn't explain "the rivers of rust that workers photographed on the reactor lid in 2000, 18 months before Exponent says major corrosion is supposed to have begun." [4] On January 20, 2006, FirstEnergy acknowledged a cover-up of serious safety violations by former workers at Davis-Besse, and accepted a plea bargain with the U.S. Department of Justice in lieu of possible federal criminal prosecution. In the agreement, the company agreed to pay fines of $23 million, with an additional $5 million to be contributed toward research on alternative energy sources and to Habitat for Humanity as well as to pay for costs related to the federal investigation. In addition, two former employees and one former contractor were indicted for purposely deceiving Nuclear Regulatory Commission (NRC) inspectors in multiple documents (including one videotape) over several years, hiding evidence that the reactor pressure vessel was being seriously corroded by boric acid. The maximum penalty for the three is 25 years in prison. The indictment also cites other employees as providing false information to inspectors, but does not name them. In 2005, the NRC identified two earlier incidents at Davis-Besse as being among the top five events (excluding the actual disaster at Three Mile Island) most likely to have resulted in a nuclear disaster in the event of a subsequent failure. [4] Space solar power offers the prospect of abundant electric power without trusting the excellent safety record of public utilities which you find so reassuring, and without the track record of merely killing fifty people at Chernobyl. By the way, how many other people were permanently impaired at Chernobyl by exposure to radiation? How many people here in Ohio would have been sickened or killed by radiation if the rotted-out reactor lid hadnt been caught barely in time? I guess only hystericists worry about that, though. Political problems are real, even if not technical, and they are the reason nuclear plants are not the answer to the burgeoning energy shortage.
Nuclear power plants have an excellent safety record and 90% availability. Newer models that have been and will be designed in the future are even safer, many with an inherent invulnerability to "meltdown."
Even in what is the virtually absolute-worst-case of Chernobyl, a grand total of fifty people have died from that catastrophe thus far. Compare that with the death toll from coal mining not to speak of the from the dirty particulates as well as substantial radioactivity emitted from coal-fired power plants.
and the problems of nuclear waste disposal.
The waste problem has been enormously over-hyped. The idea that we must come up with a "solution" to the waste that must work without any human intervention whatsoever (or even looking in to see how things are going) for hundreds of thousands of years is ludicrous and purely an artificial problem. A workable solution in my view would be to simply put all the waste (all the highly radioactive waste generated in the industry's history by all the nuclear plants in the United States -- 20% of the nation's power supply -- would fit within a 250 ft. cube) in one spot and put a guard on it. However, going well beyond that, the waste depository under construction at Yucca Mountain in Nevada appears to be an excellent solution for the time being.
The fact that none of the nuclear plants on the drawing board in the U.S. is now under construction underlines those problems.
It underlines the political problems that the U.S. and other countries have faced due to anti-nuke hystericists, not technical problems.
As one who lives near a nuclear plant which recently was forced to shut down because of the corrosion of the reactor lid which endangered the entire community,
And precisely how much "danger" was the community in, pray tell? Not very much I'd be willing to bet.
I am especially conscious of those issues. Politically, I don't believe we "can" build that number of nuclear plants in the U.S.
On the contrary, all it takes is the will.
Michael McNeil
MArk: I expect most folk don't know that the radioactive waste we're talking about is SOLID waste, and yes, it probably could fit in a cube 250 feet on a side however, the waste is still generating a considerable quantity of heat, so putting all that in a single lump would likely entail more problems of containment. The principal problem with waste is the short lived radionucleotides, those that must be retained in a water pond until they've decayed enough to be compacted into solid form. That takes quite a while. Right now we have every nuc facility in the country storing such waste on site, because there is no where else to put it and transporting such "hot" isotopes across country is really dangerous, such that most states refuse to allow a train carrying such across their borders. Flying it to the Yucca facility isnot a very good idea either. I expect, for short term energy deficiency, more nucs will be built but I hope we canbegin buildingsolar power sats soon enough to negate the necessity of nuc plants. The best place for nuc(fission) plants is in space, where we will need them for any sigificant development/travel beyond the immediate terrestrial environment. Of course, I still hope the Polywell reactor pans out. No matter what we do, at least in the short term, we will likely need a broad spectrum of power sources to meet our expanding population/economic growth. Fission, fusion, hydro, solar,power sats, wind, coal etc. Over time, the cleanest, most cost effective modes will win and I expect that will prove to be fusion(from the sun or man made). Gary 7
That makes me feel so much safer. See the attached: In an "attempt to win a $200 million insurance dispute," FirstEnergy publicly reversed course on its responsibility for the near-catastrophe at the Davis-Besse nuclear plant near Toledo, Ohio. "FirstEnergy has abruptly shrugged off the blame it once accepted for repeatedly missing a football-size rust hole growing in the lid of the radioactive, high-pressure reactor," reported The Plain Dealer. "At the time, the utility paid $33.5 million in criminal and civil fines to acknowledge its culpability for failing to stop the corrosion and for misleading government regulators." [3] FirstEnergy then claimed that "corrosion ate through the steel lid so quickly -- in four months, not the previously accepted four years -- that normal biennial inspections couldn't have caught it." The "new version of events" was put forward by Exponent Failure Analysis Associates, a consultant to FirstEnergy. But the consultant's report didn't explain "the rivers of rust that workers photographed on the reactor lid in 2000, 18 months before Exponent says major corrosion is supposed to have begun." [4] On January 20, 2006, FirstEnergy acknowledged a cover-up of serious safety violations by former workers at Davis-Besse, and accepted a plea bargain with the U.S. Department of Justice in lieu of possible federal criminal prosecution. In the agreement, the company agreed to pay fines of $23 million, with an additional $5 million to be contributed toward research on alternative energy sources and to Habitat for Humanity as well as to pay for costs related to the federal investigation. In addition, two former employees and one former contractor were indicted for purposely deceiving Nuclear Regulatory Commission (NRC) inspectors in multiple documents (including one videotape) over several years, hiding evidence that the reactor pressure vessel was being seriously corroded by boric acid. The maximum penalty for the three is 25 years in prison. The indictment also cites other employees as providing false information to inspectors, but does not name them. In 2005, the NRC identified two earlier incidents at Davis-Besse as being among the top five events (excluding the actual disaster at Three Mile Island) most likely to have resulted in a nuclear disaster in the event of a subsequent failure. [4] Space solar power offers the prospect of abundant electric power without trusting the excellent safety record of public utilities which you find so reassuring, and without the track record of merely killing fifty people at Chernobyl. By the way, how many other people were permanently impaired at Chernobyl by exposure to radiation? How many people here in Ohio would have been sickened or killed by radiation if the rotted-out reactor lid hadnt been caught barely in time? I guess only hystericists worry about that, though. Political problems are real, even if not technical, and they are the reason nuclear plants are not the answer to the burgeoning energy shortage.
Nuclear power plants have an excellent safety record and 90% availability. Newer models that have been and will be designed in the future are even safer, many with an inherent invulnerability to "meltdown."
Even in what is the virtually absolute-worst-case of Chernobyl, a grand total of fifty people have died from that catastrophe thus far. Compare that with the death toll from coal mining not to speak of the from the dirty particulates as well as substantial radioactivity emitted from coal-fired power plants. and the problems of nuclear waste disposal.
The waste problem has been enormously over-hyped. The idea that we must come up with a "solution" to the waste that must work without any human intervention whatsoever (or even looking in to see how things are going) for hundreds of thousands of years is ludicrous and purely an artificial problem. A workable solution in my view would be to simply put all the waste (all the highly radioactive waste generated in the industry's history by all the nuclear plants in the United States -- 20% of the nation's power supply -- would fit within a 250 ft. cube) in one spot and put a guard on it. However, going well beyond that, the waste depository under construction at Yucca Mountain in Nevada appears to be an excellent solution for the time being. The fact that none of the nuclear plants on the drawing board in the U.S. is now under construction underlines those problems.
It underlines the political problems that the U.S. and other countries have faced due to anti-nuke hystericists, not technical problems.
As one who lives near a nuclear plant which recently was forced to shut down because of the corrosion of the reactor lid which endangered the entire community,
And precisely how much "danger" was the community in, pray tell? Not very much I'd be willing to bet.
I am especially conscious of those issues. Politically, I don't believe we "can" build that number of nuclear plants in the U.S.
On the contrary, all it takes is the will.
Michael McNeil
>While I'm not at all averse to orbiting solar power satellites, as I
>noted before we don't strictly speaking "need" to build them,
>because one can also build nuclear power plants -- which are also
>"sustainable" -- down here on Earth.
best thing in terms of scaling and being there when you need them.
But if we can build power sats less expensively than nuclear plants
it makes sense to do so.
Nuclear plants cost in the range of $8000 per installed kW.
I can make a case for power sats in the range of $800/kW.
it would be easy to do with a moving cable space elevator (on the
order of $10/kg to GEO). There is another way that might do it, a
suborbital rocket stage to get out of the atmosphere and a gigantic
ablation laser to push 100 tons per hr out to GEO.
Details if anyone is interested.
Keith Henson
Gary Fusion (man-made) would be great, but, as a recent article about current efforts at CERN pointed out, for the past 40 years every question about when fusion would be ready to produce usable energy for general use has gotten the same answer: in about 30 years. Its hard to count on a technology that stubbornly resists being translated from theory to practice. --Mark
Even in what is the virtually absolute-worst-case of Chernobyl, a grand total of fifty people have died from that catastrophe thus far. Compare that with the death toll from coal mining not to speak of the from the dirty particulates as well as substantial radioactivity emitted from coal-fired power plants. and the problems of nuclear waste disposal.
The waste problem has been enormously over-hyped. The idea that we must come up with a "solution" to the waste that must work without any human intervention whatsoever (or even looking in to see how things are going) for hundreds of thousands of years is ludicrous and purely an artificial problem. A workable solution in my view would be to simply put all the waste (all the highly radioactive waste generated in the industry's history by all the nuclear plants in the United States -- 20% of the nation's power supply -- would fit within a 250 ft. cube) in one spot and put a guard on it. However, going well beyond that, the waste depository under construction at Yucca Mountain in Nevada appears to be an excellent solution for the time being. The fact that none of the nuclear plants on the drawing board in the U.S. is now under construction underlines those problems.
It underlines the political problems that the U.S. and other countries have faced due to anti-nuke hystericists, not technical problems.
As one who lives near a nuclear plant which recently was forced to shut down because of the corrosion of the reactor lid which endangered the entire community,
And precisely how much "danger" was the community in, pray tell? Not very much I'd be willing to bet.
I am especially conscious of those issues. Politically, I don't believe we "can" build that number of nuclear plants in the U.S.
On the contrary, all it takes is the will.
Michael McNeil
> Nuclear plants cost in the range of $8000 per installed kW.
>
> I can make a case for power sats in the range of $800/kW.
>
> it would be easy to do with a moving cable space elevator
> (on the order of $10/kg to GEO). There is another way that
> might do it, a suborbital rocket stage to get out of the
> atmosphere and a gigantic ablation laser to push 100 tons
> per hr out to GEO.
>
> Details if anyone is interested.
understand it.
>
> > Nuclear plants cost in the range of $8000 per installed kW.
> >
> > I can make a case for power sats in the range of $800/kW.
> >
> > it would be easy to do with a moving cable space elevator
> > (on the order of $10/kg to GEO). There is another way that
> > might do it, a suborbital rocket stage to get out of the
> > atmosphere and a gigantic ablation laser to push 100 tons
> > per hr out to GEO.
> >
> > Details if anyone is interested.
>
>Well yeah I'm interested! Hopefully I'll also be able to
>understand it.
equation. For example using the best chemical rockets a 6000 ton
liftoff rocket delivers 100 tons to GEO, that's one part in 60.
Lasers launch has been worked of for years because it offers a much
higher exhaust velocity, which means for a given amount of reaction
mass it picks up lot more velocity. The problem is that it takes
huge lasers to make it work or the payloads are small. The usual
metric is a MW/kg or a GW/ton.
Low exhaust velocity is ok when you are not trying to pick up much
speed. You can get to .7 of the exhaust velocity with an equal
amount of payload and fuel.
This is probably not optimized, but the proposal is to put up a 50
ton laser stage starting with a 300 ton liftoff rocket. That's less
than the smallest fully fueled 747 and you send one up every 15
minutes for a 100 t/hr materials flow.
As the laser stage gets above the atmosphere, it's batted sideways by
a 4 GW ablation propulsion laser. The lasers and the mirror needed
to make it work are expected to cost around $100 billion. Written
off over ten years that's a $10 billion a year. It lifts close to a
billion kg/year so the cost is down around $10/kg. The rocket stage
will cost $30-60/kg.
25 tons of the 300 ton liftoff mass makes it to GEO, one part in 12
rather than one part in 60. *And* you fly the rocket at least twice a day.
If the power sats mass 4kg/kw and we want the transport cost to be
not much higher than half, the we can stand up to $100/kg.
Why hasn't anyone come up with this before?
I came at it from looking at scale of the market for an entirely
imaginary space elevator. When you are thinking of a million ton per
year traffic throughput and apply lasers to it, it makes sense.
Putting the laser stage up by rocket and pushing it for a relatively
long time with the laser reduces the amount of laser needed by about 6.
Lots and lots of details to work on. This taps into Dr. Jordin
Kare's decades of work. Could not be done without standing on his shoulders.
http://www.htyp.org/dtc
Keith Henson
PS I am working on a set of power point slides for an important
presentation. If there is someone on this list with the technical
skills to check a lot of chemistry, physics and orbital mechanics who
would like to review the slides, please get in touch.