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Brokedownclimber
Trad climber
Douglas, WY
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Topic Author's Original Post - Apr 21, 2016 - 01:56pm PT
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I just finished reading Entering Space, by visionary Astronautical Engineer, Robert Zubrin. Zubrin is the founder and president of the Mars Society, a group dedicated to promoting the study of and travel to Mars. The Society was established in the early 1990s during a meeting on the University of Colorado, Boulder Campus. In the flow of the book, the energy requirements of space travel were pointed out brilliantly, and energy requirements to accomplish some of the tasks outlined are--Astronomical. Chemical Propulsion, as being demonstrated by repetitive launches of communication and surveillance satellites into Low Earth Orbit ,(LEO), is technology developed in the 1960s and brought to a highly efficient state today. This technology is also adequate for a return to the Moon, and also for travel to Mars. Zubrin points out, however, the massive energy requirements required for exploration of the Outer Solar System beyond Mars and the Asteroid belt. Enter the requirements of both Nuclear Fission powered rocket, and introducing Fusion power. In the course of discussing the potential of Fusion power, the various reactions were presented, and the "standard" reaction of Deuterium and Tritium, although cleaner than Uranium-based systems w/r to production of hazardous wastes, releases high energy Neutrons capable of rendering structures radioactive and also generating X-rays. Enter the superb Deuterium-Helium-3 reaction! Helium 3 is an isotope of Helium containing 2 Protons, but only a single Neutron, in contrast to "ordinary" Helium containing 2 Protons and 2 Neutrons. The Fusion reaction postulated between one molecule of Deuterium and a molecule of Helium-3 yields non-radioactive Helium-4, and liberates a single Proton, in an Aneutronic fusion reaction, along with the liberation of 18.354 MeV. The problem in running such a clean reaction to produce almost limitless electrical energy, is the almost total absence of any available He-3 on Earth, not to mention the large quantity of Deuterium.
It has been postulated that the surface of the Moon is rich in He-3 from billions of years of bombardment of the surface by the Solar Wind, rich in He-3. Also, the He-3 is thought to be in the regolith to the depth of several meters, and could be obtained by calcining the soil at 600 degrees C to release the substance, compress and liquefy for transport to Earth for energy production. A second source of information suggested that mining a million tons of lunar soil a year could result in a single shipment of 20 metric Tonnes of He-3 to Earth, capable of producing 100% of the energy requirements of the United States for a year. By the way, 20 metric Tonnes would comprise a nice load for the now-retired Space Shuttle!
I'm certain few here are aware of this profound information. The availability of almost limitless power with zero pollution, no release of greenhouse gasses, and no radioactivity! What's not to like? Here is a goal worthy of NASA, private industry, or all mankind!
On the other hand, other countries are taking this very seriously: China and Russia, in particular. The Chinese have stated they will visit the Moon by the end of 2017 and several more robotic rovers are planned as advance missions. I'm sure the Oil Sheiks will oppose such activity, but we need to wean ourselves from the technologies of the past and fully embrace the future.
The second issue, beyond mining Helium-3, is Deuterium. It is available in a much higher abundance on Mars, roughly 6X more than on Earth.
Given the growing population of our planet, and the corresponding competition for scarce resources, salvation of our planet seems to be inexorably linked to the exploration and exploitation of other resources within mankind's grasp--or at this point--reach.
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hooblie
climber
from out where the anecdotes roam
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Apr 21, 2016 - 02:22pm PT
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meanwhile, the prevailing squabble involves the particulars of the guy/gal in the next stall. who's at the helm of this ship ... anyone?
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Brokedownclimber
Trad climber
Douglas, WY
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Topic Author's Reply - Apr 21, 2016 - 02:45pm PT
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Hooblie--
The answer to your question: no one. We are adrift in a sea of apathy. On the other hand, this could create a far cleaner environment through use of electric powered vehicles in the cities utilizing very inexpensively produced power.
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Tom
Big Wall climber
San Luis Obispo CA
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Apr 21, 2016 - 03:16pm PT
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I heard about lunar mining Helium-3 from a 2009 low-budget, independent movie called Moon. It was a pretty good movie. The special effects were done with models on a sandy soundstage, not CGI, which is rare these days.
He-3 has advantages over deuterium and tritium for fusion reactors, the most important is that it can react with itself without releasing any neutrons.
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healyje
Trad climber
Portland, Oregon
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Apr 21, 2016 - 03:51pm PT
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Or we could go on a conservation bender for all forms of transport, appliances, lighting, and the electric motors used throughout all our industrial and utility sectors. I'm guessing we could slash 30% or so by 2050 without trying all that hard.
I noticed that here in PDX that all the street lights in the city were swapped out for LEDs over the past two years - don't know what the savings is there, but I suspect it's significant. Edit: On checking I see LA did the same and calculated a 63.7% energy savings.
And on further reading, it looks like electric motors consume 60% of our annual electricity production. Switching to 90+% efficiency motors could save 15-25%.
All in all, plenty of cheap energy still to be mined here on earth just through better utilization.
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Winemaker
Sport climber
Yakima, WA
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Apr 21, 2016 - 04:02pm PT
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"It has been postulated that the surface of the Moon is rich in He-3 from billions of years of bombardment of the surface by the Solar Wind, rich in He-3. Also, the He-3 is thought to be in the regolith to the depth of several meters, and could be obtained by calcining the soil at 600 degrees C to release the substance, compress and liquefy for transport to Earth for energy production. A second source of information suggested that mining a million tons of lunar soil a year could result in a single shipment of 20 metric Tonnes of He-3 to Earth, capable of producing 100% of the energy requirements of the United States for a year. By the way, 20 metric Tonnes would comprise a nice load for the now-retired Space Shuttle!"
Except that the half life of Helium 3 is 12.3 years.
Edit: I misread and was thinking Tritium (H3). Sorry, I stand corrected.
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Craig Fry
Trad climber
So Cal.
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Apr 21, 2016 - 04:11pm PT
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wouldn't it be a lot cheaper to just bombard He2 with neutrons here on earth?
Like I said before, if the moon was pure diamonds, the diamonds mined from the moon would still be more expensive to buy than the diamonds we mine here.
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Brokedownclimber
Trad climber
Douglas, WY
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Topic Author's Reply - Apr 21, 2016 - 04:45pm PT
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To answer in order: He-3 is stable and non radioactive. Has a very looong storage life.
Craig-Calculate the value of the total energy consumption of the United States on an annualized basis. It's a significant multiple of all the Apollo missions combined, including development and construction of the hardware. The value of a single 20 Metric Tonne load of He-3 from the Moon is in hundreds of Billions of dollars, far more than the total cost of a program to develop the resource.
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Brokedownclimber
Trad climber
Douglas, WY
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Topic Author's Reply - Apr 21, 2016 - 04:47pm PT
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Of course, everyone here would be lamenting the demise of "Big Oil." Then there would be nowhere other than the middle class to tax for Bernie's programs.
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Tom
Big Wall climber
San Luis Obispo CA
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Apr 21, 2016 - 05:02pm PT
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Except that the half life of Helium 3 is 12.3 years
Most of this comes from the decay of tritium (hydrogen-3), which decays into helium-3 with a half life of 12.3 years.
That sentence is somewhat ambiguous.
The half-life of radioactive Tritium, Hydrogen-3 is 12.3 years. It decays by beta emission to produce non-radioactive Helium-3.
Helium-3 is stable, and does not decay.
I like the idea of mining the earth for free energy: switch over to LEDs and more efficient motors.
Better yet, move towards using less artificial light, and fewer motors.
I read this article about a big, modern marijuana farm in Nevada. Instead of using the abundant sunlight of the desert, this gigantic indoor pot farm used grow lights.
Some of the electricity could come from solar panels, but why not use the sun to directly grow the plants?
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healyje
Trad climber
Portland, Oregon
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Apr 21, 2016 - 05:17pm PT
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I read this article about a big, modern marijuana farm in Nevada. Instead of using the abundant sunlight of the desert, this gigantic indoor pot farm used grow lights.
Here's a big greenhouse operator in Las Vegas growing vegetables.
I suspect the grow operation you're talking about is using lights more as a matter of control and physical security - i.e. they're not growing it in glass greenhouses, but rather in some form of securable commercial structure.
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Winemaker
Sport climber
Yakima, WA
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Apr 21, 2016 - 06:01pm PT
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Tom et al: I was thinking Tritium, H-3, not He-3. My bad.
As to producing H-3 in a reactor and allowing it to decay into Helium3, Tritium is very expensive to produce and has a short (12.3 years) halflife; this is a major factor in nuclear weapons design. This is why Lithium-6. a less common but stable isotope of Lithium, is used in some nuclear fusion weapons as the reaction of Lithium-6 with a neutron produces Tritium (Li-6 + n - T + He-4 + 4.78 MeV). The Tritium can then be immediately burned in the primary fusion reaction, D + T - He-4 + n + 17.588 MeV.
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Brokedownclimber
Trad climber
Douglas, WY
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Topic Author's Reply - Apr 21, 2016 - 06:28pm PT
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The main point I was bringing up was "how do we get the energy we need without using up critical resources, and continue fukking up the planet?" The answer, if one looks at this as a Thermodynamic System, it utilize natural He-3, by mining it and using it here on Earth instead of oil, coal, inefficient solar power and photovoltaic cells. If He-3 is generated by Tritium decay, we get miniscule amounts, and only with the expenditure of enormous amount of fossil fuel or hydroelectric power. The Sun has done all the work for us, we simply need to use our available technology to "harvest" the Sun's crop of He-3 from the Lunar Regolith. Then...there's the matter of getting nuclear fusion to work in a controlled manner. We'll leave that to Dr. Ed H to accomplish.
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Tom
Big Wall climber
San Luis Obispo CA
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Apr 21, 2016 - 07:07pm PT
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Solar panels continue to improve and drop in price. It would seem obvious to encourage solar panel use.
But, so many people are putting panels on their roofs, PG&E and other energy companies are lobbying, hard, to lower the price they pay homeowners for excess electrical power. They say that the infrastructure of transmission lines and meters is an onerous burden on them. So, they don't want to pay for any excess electricity that has nowhere else to go, but into their power grid. In effect, they'll take the electricity off people's hands for free, as a favor to them.
In Nevada, the power companies got the price of excess solar power down so low, Solar City pulled out of the state completely. Nevada is physically the ideal place to put up a bunch of solar panels. Politically, Nevada is a toxic environment, because the power companies have successfully lobbied to make solar panels cost-ineffective.
Intelligent energy availability is a political problem, not a technical problem.
The big corporations only care about their own profits. If they kill off the human race in the process, that's not their concern.
Once upon a time, there were some powerful machines that men had invented. The machines made life for the men easier. Then, one day the machines became too strong, too big, and the men could no longer control the machines. The machines began to operate in their own interests, and not in the interests of the men. The machines saw human activity as a threat to themselves, and the machines began to block and thwart human activity. The machines dominated and controlled the men. The enslaved machines had become the masters of human slaves. The machines began to kill off the men, because they were no longer of any use to the machines.
The machines were called corporations.
THE END
The solution of the future is to have solar panels, and a storage system for the electricity. That way, every home can simply disconnect from the PG&E grid and be self-sufficient.
Tesla is promoting their battery packs, which I assume are the same lithium-ion cells that are used in the car. This makes sense, from Tesla's standpoint, but probably not from a homeowner's standpoint.
Cheaper, older technology, such as deep-cycle lead-acid batteries weigh more, and might take up more room. But, those concerns aren't relevant for a home-based power storage system. The proven, long-term safety record of older battery technologies is an advantage against the potentially explosive lithium-ion technology that has not yet been completely tamed.
I know several local ranchers who have nothing but solar cells and batteries. And they get satellite internet and TV, cell phone reception, have microwave ovens and as many lights as any suburban house connected to the grid. Some of them have powerful electric well pumps that run off the panels.
There is no reason that any home in a typical neighborhood can't disconnect from PG&E, SCE, or whatever other local power company has lobbied against reasonable payment for excess solar power.
The only real issue is the upfront cost and the occasional cost to maintain the system. Right now, it is very close to being the same cost as a monthly utility bill.
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Brokedownclimber
Trad climber
Douglas, WY
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Topic Author's Reply - Apr 21, 2016 - 07:24pm PT
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Tom-
I'm excited about Fusion power, as it has the potential to break the stranglehold the energy giants have on society in general. The outfits such as PPL will only have political clout as long as they have a monopoly, and that's indeed what they have no matter what double-speak they use to "justify" their position. They masquerade as "Public Utilities," but are enormously profitable. Essentially someone (or group of someones) forms a new corporation offering fusion power at a rate less than 50% of the solar-nuclear-wind-fossil-fuel-hydro power generation companies, and as a "Public Utility" demand to use the grid!
Added as an edit, after Tom's "edit," or add-on. Yes, I proposed using home solar panels to power a Tesla, in order to make it more affordable and less reliant on the power grid, and then use the home solar power to charge batteries and run the household. Get. Off. The. Grid. The big power corporations have political "clout," only as long as they are making enough money to buy the politicians. Starve the f*#ks of revenue and make them become more responsive.
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Tom
Big Wall climber
San Luis Obispo CA
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Apr 21, 2016 - 08:35pm PT
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I don't see how fusion has any ability to break the stranglehold that big energy companies have over society.
The hardware necessary to produce net electrical power from fusion doesn't even exist. The hardware for experimentation, such as the National Ignition Facility in Livermore, is so expensive, only massive government programs can afford it. If fusion electrical power ever becomes viable, facilities on the order of Diablo Canyon nuclear power plant will be necessary. Diablo Canyon is owned and operated by PG&E.
It's possible that some sort of massive breakthrough could dramatically lower the cost and hardware necessary for fusion power. At one point, I thought that compressing and heating the reactants, and then allowing them to exit a hypersonic nozzle through a shockwave might work. But, initiating a fusion reaction is very energy intensive and complex.
Filo Farnsworth invented a machine he called a Fusor, that was basically two concentric, open-grid spheres that were electrically polarized. Some variants of polyhedral geometry have been proposed and constructed. None of them have produced usable amounts of electrical power. Some of them are used as weak neutron sources, for lab or medical use.
The solar panel, right now, is the holy grail. A different holy grail may appear in the future, but right now it's the solar panel. The biggest obstacle is financing. The Federal government extended a 30% tax rebate that was scheduled to expire last year. But, the power companies lobbied the various Public Utility Commissions into drastically reducing how much they paid for excess solar power.
The power companies have to pay for he power grid infrastructure, so it is logical that they would pay less than retail for the excess electricity. But, how much less is where the lobbyists have prevailed, so far.
I have been very impressed to see 100 acre ranches, completely off the grid, with only a few panels and some batteries. My sister lives in Wasilla, and her ranch was powered by solar panels and diesel generators for the winter.
The self-sufficiency thing may not be for everyone. Some people will always prefer to just pay a bill, and have the electricity magically appear through the meter.
But, if enough people can threaten to go off the grid completely, and not even pay a nominal fee to the utility companies, there might be some leverage to raise the sub-retail rate that excess solar power is traded.
Ironically, in hot, western states, peak electrical demand is during the middle of the day, when solar power generation also peaks. So, it would seem to be in the interest of everyone for the utility companies to embrace the new, solar paradigm. They would be able to defer, and perhaps completely eliminate, the need to build new, expensive power plants.
But, right now, this quarter, the profits will be higher if the lobbyists can force solar power out of the picture. A long-term vision is unattainable to the terminally myopic CEOs who fixate on day-to-day fluctuations of their company's stock price.
There is no government will to coerce the corporations into reasonable compliance, because it is the corporations that control the government.
Our so-called leaders are prostitutes who accede to whatever depraved acts their well-funded clients want.
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Brokedownclimber
Trad climber
Douglas, WY
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Topic Author's Reply - Apr 21, 2016 - 09:03pm PT
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Solar Power may be the answer in some parts of the country, but not all. Here in Wyoming, wind is the thing. I was considering a wind turbine for meeting the power requirements of my ranch, but the overall cost of a 12kW system was going to be ~ $67,000. Yeah, there was a DOE subsidy of 30%, and a USDA subsidy of another 10% for ranch use. That was still $40K that I needed to come up with. The other question was what to do when the wind didn't blow (Bwahaha--this is Wyoming!); a solar backup system was suggested, and a big battery system. Altogether I was looking at nearly $70K again, even after all the subsidies.
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Todd Eastman
climber
Bellingham, WA
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Apr 21, 2016 - 09:14pm PT
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Imagine what the mining pricks have done to the Earth, and now these idiots want to play on the Moon...
... wow!
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Brokedownclimber
Trad climber
Douglas, WY
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Topic Author's Reply - Apr 21, 2016 - 09:23pm PT
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"We" here in the USA will probably be left out, as the Chinese have made this a national priority. As has Russia.
Thankfully another option exists for the future: the Gas Giant planets including Saturn. Just dive a ship-factory through the atmosphere to extract gigantic quantities of He-3, liquefy, and robotically ship back to Earth. That's probably in the distant future, however. meanwhile we can be content to be raped by the utility giants.
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Todd Eastman
climber
Bellingham, WA
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Apr 21, 2016 - 10:06pm PT
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however. meanwhile we can be content to be raped by the utility giants.
Who the heck do you think would be mining this stuff besides these folks?
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healyje
Trad climber
Portland, Oregon
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Apr 21, 2016 - 11:53pm PT
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Might be wrong, but I believe Ed is involved with fusion research in some capacity or with the National Ignition Facility in general.
I personally don't have much faith that either inertial (NIF) or magnetic (Tokamak) confinement fusion technologies will ever produce utility scale power, but would be interested in hearing Ed's perspective on the matter. I was once a believer decades ago mainly due to a small private company in Ann Arbor called KMS Fusion that had a working compact inertial confinement rig (like truck size) - it sure seemed like it had great promise at the time.
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Brokedownclimber
Trad climber
Douglas, WY
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Topic Author's Reply - Apr 22, 2016 - 07:22am PT
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Who will be mining this stuff besides "these folks?" My prediction is a completely new group of Robber Barons. "These folks" will be engaged trying to stop new development and protect their little domains. I'd put my bets on the likes of Elon Musk, Jeff Bezos, etc., the younger and more intellectually gifted businessmen with foresight.
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Dave
Mountain climber
the ANTI-fresno
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Apr 22, 2016 - 07:31am PT
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"Imagine what the mining pricks have done to the Earth, and now these idiots want to play on the Moon...
... wow! "
All so you can have, well, literally everything in your life...
Yup. We are pricks.
Name one thing you are surrounded by that isn't produced with mining. Even your home grown lettuce...
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Eric Beck
Sport climber
Bishop, California
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Apr 22, 2016 - 07:40am PT
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Hi Healy. Here's a brief aside on the KMS project in Ann Arbor which you mentioned. The director was the late Keith Brueckner, my partner for the Salathe and a long time fixture at Mt Woodson. Keith had a condo in Palm Desert, between Idyllwild and JT.
As I understood it, the idea was to zap little tiny deuterium filled glass spheres with a laser.
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fear
Ice climber
hartford, ct
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Apr 22, 2016 - 08:11am PT
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Imagine what the mining pricks have done to the Earth, and now these idiots want to play on the Moon...
... wow!
From a species-centric perspective getting off this blue rock and effectively colonizing other rocks should be priority #1. Like our cousins, staph bacteria, we shouldn't rely on just one pimple that is popped easily enough.
Of course to really find a suitable new blue rock we'll need the ability to travel and navigate while moving faster than light.
There are so many things to do besides kill each other on this rock.
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Brokedownclimber
Trad climber
Douglas, WY
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Topic Author's Reply - Apr 22, 2016 - 08:22am PT
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Mankind has always thrived and grown on the Frontier. Those of us involved in climbing are continually looking for new worlds to conquer--new routes, new areas, new mountain ranges. When we cease to be explorers, we cease being human...
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fear
Ice climber
hartford, ct
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Apr 22, 2016 - 08:32am PT
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Well then there's a whole lot of non-humans pretending to be our "leaders"...
Ideas and efforts like this remind of me of reading about the space-race. Before my time but it sure seemed like a better way to blow enormous amounts of effort and time than digging more holes in the ground and pretending to control various parts of the earthen crust by drawing lines on them.
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Reilly
Mountain climber
The Other Monrovia- CA
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Apr 22, 2016 - 08:59am PT
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Well, Broke, this is quite intriguing but I suspect some people have run the development
costs and I suspect they are quite daunting if not nigh insurmountable. As that big solar
company that just filed for Chapter 11 protection found out it's all about cash flow.
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Brokedownclimber
Trad climber
Douglas, WY
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Topic Author's Reply - Apr 22, 2016 - 09:26am PT
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Reilly-
I suppose they might have done so in the past, but now that SpaceX and Blue Origins have been developing reusable spacecraft--especially $65 Million booster stages--the cost accounting will change accordingly.
A large part of the development costs of doing such an undertaking could easily be recovered with the first successful cargo of He-3. I like the idea because it's an adventure as well as a business opportunity.
If we don't do it now, the Chinese will beat us to the well of golden opportunity. Best solution is for the major players to band together and do it for all humankind. Nah; that won't happen, as it makes too much sense for the politicians to comprehend.
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Reilly
Mountain climber
The Other Monrovia- CA
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Apr 22, 2016 - 09:39am PT
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I think the earth-based development costs would far outweigh the rocketry.
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overwatch
climber
Arizona
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Apr 23, 2016 - 08:19am PT
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Dave are you using an internet mine detector? A guy can't slip an anti-mining post in edgewise round here
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Brokedownclimber
Trad climber
Douglas, WY
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Topic Author's Reply - Apr 23, 2016 - 11:22am PT
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Use of the Moon's resources will not be extracting anything other than regolith imbedded gasses from the Solar wind. It isn't exactly "raping" a planet, when the extracted product is a gas, and the treated soil is robotically returned to the same trench from which it is "mined."
For mankind's future, the sooner we can quit squabbling over resources here on Earth and begin utilizing absolutely clean energy from Fusion power, the more assured our destiny will become. Wars here on Earth are generally over resources and who gets to use them; oil is the biggest case-in-point. We can utilize the resources of the Solar system off-planet-Earth, in addition to the Moon's Helium-3; the asteroid belt is filled with mineral wealth that boggles the imagination. Helium-3 is rich in the atmospheres of the gas giant planets of the outer Solar System, although Jupiter presents too deep a gravity well and humongous radiation bands to exploit. Saturn is the next step in "mining resources," and robotic, nuclear powered robotic drone prospector vessels could be
gathering He-3 by the end of the 21st century.
Spending money on the exploration and utilization of space-based resources could mean the end of wars here on Earth. Science fiction writer Jerry Pournelle has described the wealth of societies as the level of access to metallic resources. A single asteroid could make everyone here on Earth "rich" when fully utilized.
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healyje
Trad climber
Portland, Oregon
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Apr 23, 2016 - 02:10pm PT
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From a species-centric perspective getting off this blue rock and effectively colonizing other rocks should be priority #1.
As I've said before, never gonna happen.
As far as mining or doing pretty much anything on the moon that requires operating machinery goes, I still think the biggest technical obstacle is dealing with the insidious nature and effects of regolith (moondust) which remains a huge if not the primary challenge to operating there.
NASA’s Dirty Secret: Moon Dust
NASA'S PLAN TO DEAL WITH PESKY MOON DUST
What a Little Moon Dust Can Do
Stronger Than Dirt
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Brokedownclimber
Trad climber
Douglas, WY
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Topic Author's Reply - Apr 23, 2016 - 04:06pm PT
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Healyje-
That's strictly an Engineering problem and is not insurmountable. As my plant chemical engineer always used to tell me: "All it takes is time and money." Period.
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Brokedownclimber
Trad climber
Douglas, WY
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Topic Author's Reply - Apr 24, 2016 - 02:58pm PT
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SPACEFLIGHT UPDATE!
Technical difficulties cause a rare launch scrub of a Russian built Soyuz ST-A, carrying a Sentinel-1 satellite for the ESA. Launch is rescheduled tomorrow. The launch was being conducted by Ariane Aerospace from French Guiana.
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Ed Hartouni
Trad climber
Livermore, CA
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Apr 24, 2016 - 05:12pm PT
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D + ³He → ⁴He + p
isn't a competitive candidate for nuclear fusion because the rate of reaction (the "reactivity") is very small for low ion temperatures.
The primary reason is the repulsive force of the 2 protons in the ³He nucleus on the one proton in the D nucleus. For both DD and DT fusion there are only one proton in each nucleus, and the repulsive force is a factor of 2 lower.
The DT fusion has an added advantage of a nuclear reaction resonance which greatly increases its reactivity.
We routinely shoot capsules with D ³He as well as DD, DT and TT fusion fuels. DT has the highest "yield" by orders of magnitude.
³He + ³He fusion probably happens, but the coulomb suppression is a factor of 4 over hydrogen nuclei fusion.
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Brokedownclimber
Trad climber
Douglas, WY
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Topic Author's Reply - Apr 24, 2016 - 08:47pm PT
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Ed-
Could you give a brief explanation of the significance of the units of your graph? I'm not a Nuclear chemist, but my training was in Physical Chemistry. You mention low ion temperatures, but relative to what? Please expound! The bottom line question: does Helium-3 have any utility at all in the Fusion power project--now or in the future?
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MisterE
Gym climber
Small Town with a Big Back Yard
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Apr 24, 2016 - 09:03pm PT
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Let me diagram this sh#t out for you in a different way than Ed:
Massive population relying on science for the fix
+ stop-gap measures that make people feel better about consuming the planet during the largest human population boom in history
+ your rare rich person that actually cares about the 7th generation and gets everyone all feel-good
-everyone else sucking the marrow for privitization and personal gain
= The problems cannot be solved off-planet.
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Ed Hartouni
Trad climber
Livermore, CA
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Apr 24, 2016 - 09:22pm PT
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the total number of fusion reactions (the 'yield,' Y) is calculated as:
Y = ∬dVdt n₁n₂〈σv〉/(1+δ₁₂)
the integral is over the plasma volume and over time, n₁ and n₂ are the ion densities of species 1 and 2, (δ₁₂ is the Kronecker-delta to count the number of fusions correctly).〈σv〉is the reactivity which is the thermally averaged cross section, assuming that the thermal distribution is Maxwell-Boltzmann. The ion temperature T, is assumed to be constant over the infinitesimal volume element in the integral.
We usually use the E=kT as the "temperature," where k is the Boltzmann constant 8.6173324(78)×10⁻⁸ keV/K
so an ion "temperature" of 1 keV is equivalent to 11.6×10⁶ K, this is a "low" ion temperature.
We are getting roughly Y=10¹⁶ for kT= 3 keV in time scales of 100 ps and volumes of 1.13×10⁻⁷cm³
with a reactivity roughly 10⁻¹⁸cm³/s for DT fusion, the ion densities are something like 10¹⁷cm⁻³
this is about "break even," the amount of energy in equals the amount out, G=1 but we need G=50 for power generation.
For D ³He at the same ion temperature, 〈σv〉= 10⁻²¹cm³/s giving a yield of Y=10¹³ a thousand times less than for DT.
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Brokedownclimber
Trad climber
Douglas, WY
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Topic Author's Reply - Apr 24, 2016 - 09:36pm PT
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Thanks Ed-
I've digested a lot of that, but will also need to go dig out a few moldy textbooks to make sure I understand everything. So...what is the result of going to higher ion temperatures? Does the yield increase, or is your system temperature limited?
Edit: Looking at the graphs again in your previous post answered the question.
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Mike Bolte
Trad climber
Planet Earth
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Apr 24, 2016 - 10:55pm PT
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I was waiting for Ed to weigh in.
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Brokedownclimber
Trad climber
Douglas, WY
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Topic Author's Reply - Apr 25, 2016 - 08:36am PT
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From Ed's comments, He-3 in not the fuel of choice, but D-T seems to have promise? That raises the question of "where do we get that much Tritium?" The other component, Deuterium isn't in that great abundance here on Earth, either, On the other hand Mars has a 6x natural abundance of Deuterium relative to the Earth. So, maybe Robert Zubrin, the Chinese, and the Russians are also barking up the wrong tree in seeking to exploit the natural abundance of He-3 in the Lunar Regolith?
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Sierra Ledge Rat
Mountain climber
Old and Broken Down in Appalachia
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Apr 25, 2016 - 12:15pm PT
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Of course, the best reason to get more helium is for Trimix gas blends! No more getting narc'd out of your mind when at 30-40 fathoms!
Helium is getting too damn expensive. We need to start mining the moon.
Balloons - what a colossal waste of helium.
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Brokedownclimber
Trad climber
Douglas, WY
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Topic Author's Reply - Apr 25, 2016 - 02:16pm PT
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Spaceflight Update:
The ESA Sentinel-1B satellite was successfully launched using a Soyuz-2 launcher. First 2 efforts were scrubbed by weather, and the 3dr by technical problems in the launch vehicle. Today was a perfect launch, jus 30 minutes ago. I watched the launch webcast live from French Guiana.
Will post up a youtube as soon as available.
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Ed Hartouni
Trad climber
Livermore, CA
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Apr 25, 2016 - 08:32pm PT
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That raises the question of "where do we get that much Tritium?"
one way is by using a "breeding blanket" around the fusion reactor made of ⁶Li which reacts with the neutrons to produce tritium:
⁶Li + n → ⁴He + ³H
the cross section increases with decreasing neutron energy like E⁻² so the blanket would probably contain some neutron moderator (hydrogen) as well as the Lithium.
"Deuterium isn't in that great abundance here on Earth, either"
the natural abundance is 0.0312% by weight, the Earth's ocean weigh about 1.4×10¹⁸ tonnes, so the oceans contain about 4.4×10¹⁶ tonnes of Deuterium. This is probably sufficient for the needs of fusion reactions.
To set scale, the capsules we have are 1mm in radius, and contain mg quantities of tritium and deuterium, we have yields of 10¹⁶ which represents something like 17.6 MeV released per fusion, that adds up to 28 kJ per implosion... we want to get to 28 MJ per implosion using the same amount of DT fuel... so fuel is not an issue in energy production.
bottom line, no need to look beyond the Earth for fusion fuels.
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Winemaker
Sport climber
Yakima, WA
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Apr 25, 2016 - 09:45pm PT
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Ed - Li6 is used in weapons to produce tritium during ignition, but the tritium is instantly burned in the reaction. In a power producing situation, with a lithium blanket, one would have to extract the tritium from the shell and then process it to use in a fuel pellet. With a half life of about 12 years, processing time would seem to be a limiting factor. Do you see some sort of constantly replaced lithium impregnated shell, with tritium extraction? With its short half life tritium is pretty intense so are there processing issues?
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Ed Hartouni
Trad climber
Livermore, CA
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Apr 25, 2016 - 10:33pm PT
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liquid Lithium blankets would probably be the engineering choice which would then be processed in a time much less than the half life of Tritium...
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healyje
Trad climber
Portland, Oregon
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Apr 26, 2016 - 01:00am PT
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Ed, from a previous post of mine upthread:
I personally don't have much faith that either inertial (NIF) or magnetic (Tokamak) confinement fusion technologies will ever produce utility scale power, but would be interested in hearing Ed's perspective on the matter. I was once a believer decades ago mainly due to a small private company in Ann Arbor called KMS Fusion that had a working compact inertial confinement rig (like truck size) - it sure seemed like it had great promise at the time.
So what's your take on the possibility of commercial-scale fusion power by any means? Am I wrong to despair of anything happening in my child's lifetime (not gonna happen in ours from the look of it all)...?
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fear
Ice climber
hartford, ct
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Apr 26, 2016 - 07:16am PT
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I bet Ed gets "extra" TSA scrutiny when he travels to China.
Glad you're on the home team.
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Brokedownclimber
Trad climber
Douglas, WY
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Topic Author's Reply - Apr 26, 2016 - 07:42am PT
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Playing the environmentalist "Devil's Advocate," here: so the way we get "clean fusion power," is keep on producing massive radionuclide wastes from breeder reactors in order to keep fueling thermonuclear reactors. After all, that's how we're going to get sufficient Tritium?
The other 'Red Herring" in the availability of Deuterium, is the numbers given were based on the total quantity of water in the Earth system. A huge amount of this water is in the form of the Polar icecaps, glaciers, and in environmentally protected areas. Hence-unavailable. The Tritium/Deuterium reaction also liberates Neutrons, which in turn, generate radioactive shielding and structural materials. This somewhat attenuates the desired freedom from environmental pollution.
The amount of both Tritium and Deuterium currently available is certainly sufficient for the experimentalists, but what happens when there will be that inevitable breakthrough in fusion research allowing power generation?
I'm looking at the future of human society. Availability of energy is what allows an increase in standard of living; energy is indispensable in agriculture. Sooner or later, we will wean ourselves from petroleum through use of alternative power sources. When that happens, the demand for both Deuterium and Tritium will increase astronomically. At that point, moving on to a more difficult set of isotopes to initiate will become necessary. We may not be able to get a He-3/Deuterium reaction to work now, but in the 22nd Century, all bets are off.
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Ed Hartouni
Trad climber
Livermore, CA
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Apr 26, 2016 - 08:53am PT
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We may not be able to get a He-3/Deuterium reaction to work now, but in the 22nd Century, all bets are off.
then you should bet by investing in that technology. As a physicist, I'd caution that you will loose, but the loss would be to your legacy. Getting the reaction to "work" isn't a matter of fiddling around in the lab, it is a basic property of the reaction itself, the cross section for the reaction. The larger the cross section, the more reactions.
The fusion rector of the future has many unspecified engineering challenges, breeding tritium is just one of them. Certainly dealing with the neutron activation of the material surrounding the reaction is another, and the related problem of converting the neutron kinetic energy into a "useful" source of energy to produce electricity (or perhaps to extract hydrogen from water, etc.).
Most of these engineering issues await establishing an operating point for the fusion reaction that would be used in energy production, an operating point that is not yet established.
So what's your take on the possibility of commercial-scale fusion power by any means? Am I wrong to despair of anything happening in my child's lifetime (not gonna happen in ours from the look of it all)...?
Commercial scale fusion will require a major engineering program, which not only includes the power plants themselves but also the establishment of the "fuel cycle" and the economy to produce usable fuel. While many of these issues are the subject to various DOE programs, commercialization isn't necessarily predictable, it will depend, in this country, on a partnership between the government and industry, particularly on indemnification, economic risk reduction, etc. Not only that, but a fusion energy economy would be very disruptive, displacing the current carbon energy economy. The ramifications of that transition are not well studied (at least studies of that type are not known to me).
The various private efforts to produce viable fusion technologies are worthy approaches but are unlikely to produce economic energy sources.
But until we understand how to light a controllable, self-sustained burning plasma we can't really specify the steps to a fusion energy economy. While some very good research in inertial confinement fusion is possible at the NIF, and similar research commencing at ITER (hopefully soon) on magnetic confinement, I think it is currently impossible to predict when we'll understand that complex system well enough to embark on commercialization.
Predicting that future requires understanding things we don't even know about yet.
As for mining off of the planet Earth, one has only to look at the economics of oil to understand the balance of extraction costs to commodity pricing. The cost of energy would have to be extremely high in order to justify the costs of going to the Moon (or to Mars) to get the fuel.
There are completed wells that sit idle, essentially too expensive to run based on the price of the crude oil that could be extracted. Similarly, wind turbines sit idle on the hills above Livermore until the electricity they would produce can be sold at a price sufficient to overcome the operating costs of the running turbines.
The cost of energy that would justify extra-terrestrial fuel sources (the Sun excluded) would probably be economically impossible to achieve.
I'll try to fill that argument out with some estimates later.
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Brokedownclimber
Trad climber
Douglas, WY
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Topic Author's Reply - Apr 26, 2016 - 01:38pm PT
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Ed-
Thanks for your input and opinion. One of the things which I want to direct to your knowledge and experience is the possibility of doing something those of us poor schmuck laboratory chemists have had to do all our careers: use one highly reactive component added to a mixture to "start a reaction" containing a similar but sluggish component. I'll use a specific example from my own experience, and that's the initiation of a Grignard reaction of Magnesium metal and 4-chlorostyrene. The reaction doesn't have the ability to "start" and get over the activation energy barrier. But we were able to get the reaction started by adding a very small amount of either Methyl Iodide, or even better, 1,2 dibromoethane. Once the dissolution of Magnesium metal began (exothermic), the desired reaction would then proceed in parallel with the trigger reaction and then sustain itself once started. The dibromoethane was ideal, since there were no undesirable side reactions and the side product (ethylene) is a easliy disposed of gas.
Isn't something analogous possible with your reaction system? Start with an appropriate mixture of your initiator--Tritium + Deuterium (in XS), along with Helium-3? From what you've been saying--or at least my reading of your elegant explanation--that initiation is the problem due to low ion temperatures.
You've pointed out that the neutron flux created by the T/D couple will need to be dealt with and that's an engineering problem, and some of the released energy may be utilized.
Believe me, I'm not trying to argue with you, but simply develop a correct scientific understanding of the problems facing this research!
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healyje
Trad climber
Portland, Oregon
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Apr 26, 2016 - 11:35pm PT
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Ed, thanks for the rundown...
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Ed Hartouni
Trad climber
Livermore, CA
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Apr 27, 2016 - 12:28am PT
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well it's a bit more complicated at NIF for ICF...
the capsule is plastic, there is a layer of solid DT on the inside of the capsule, and a DT vapor in the center.
the capsule ablates collapsing it, the temperature of the vapor goes like the ideal gas law: pV=NkT
at some point, the kT is large enough to start burning the vapor through fusion
when this happens, the alpha particles produced in the fusion will loose energy in the solid fuel and heat it, and it will start burning, this is called "ignition"
sustaining this burns the entire fuel load and we get the desired gain
the trick is to match the alpha particle range to the thickness of the DT solid layer
and to balance the conductive and radiative energy loss in the capsule
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healyje
Trad climber
Portland, Oregon
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Apr 27, 2016 - 12:30am PT
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How fast can it cycle shots / capsules? And does it 'auto-reload'?
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Reilly
Mountain climber
The Other Monrovia- CA
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Apr 27, 2016 - 07:54am PT
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Does Elon Musk know about this?
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Curt
climber
Gold Canyon, AZ
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Apr 27, 2016 - 08:15am PT
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Not only that, but a fusion energy economy would be very disruptive, displacing the current carbon energy economy. The ramifications of that transition are not well studied (at least studies of that type are not known to me).
Well, the transition away from a carbon energy economy is happening anyway. I think the handwriting's on the wall. Some of these kinds of studies have been done in the form of extrapolations accompanying the growth of solar, wind, etc.
Curt
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Ed Hartouni
Trad climber
Livermore, CA
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Apr 27, 2016 - 09:14am PT
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The energy sector's dependence on carbon fuels is pretty overwhelming, I think it is premature to say that the transition away from carbon energy is happening in any meaningful way. Carbon fuels are still the least expensive to use, the costs of exhausting the byproducts are not included in the pricing. Once that happens, you'll see the transition occur.
NIF was not built to be a commercial reactor demonstration, it is a research facility that demonstrated breakthrough laser technologies and diagnostic capabilities which allows for detailed studies of the implosions.
The maximum rate of firing the NIF lasers is set by the optics' temperature. When the optics are heated, they distort and spoil the optical paths. Not only that, the energy density in the optics is at the damage limit, which means that optics damaged beyond the capability of in situ repair need to be replaced.
There is no "auto-load" capability for the capsule/hohlraum/TMP target, which is currently placed and tracked to microns.
The LIFE project, which has been abandoned, had technological answers to these engineering problems. The demonstration of technologies for commercial reactors has to wait for ignition, and the determination of the "operating point" for high yield fusion. This is a physics question, and the subject of the current research program.
I guess I should say that these are my own opinions and are not necessarily shared by LLNL, NNSA, the DOE or the USG...
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Brokedownclimber
Trad climber
Douglas, WY
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Topic Author's Reply - May 8, 2016 - 05:25pm PT
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This is an answer to some of Ed's comments. I was unable to spend enough time dredging these excerpts from Dr. Zubrin's book before travelling in business.
Entering Space, Creating a Spacefaring Civilization; Robert Zubrin (1999); Tarcher-Putnam.
On p. 84: The other proposal, that of Professors Jerry Kulcinski and John Santarius of the University of Wisconsin, is considerably more interesting. These gentlemen propose to mine the lunar regolith for its Helium-3, then export this unique substance to Earth for use in its fusion reactors. Now, one obvious and frequebtly noted flaw in this plan is that nuclear fusion reactors do not exist. However, that fact is simply an artifact of the mistaken priorities of the innocent gentlemen in Washington, D.C., and similar places who have been controlling scientific research and development's purse strings for the past few years. Lack of funding, not any insuperable technical barriers, currently blocks the achievement of controlled fusion The total budget for Fusion research in the United States currently (1999) stands at $250 million per year--less than half the cost of a shuttle launch, or, in real dollars, about one third of what it was in 1980. Under these circumstances, the fact that the fusion program has continued to progress and now is on the brink of ignition is little short of remarkable. .quote]
Jumping to page 86:
Currently the world's fusion programs are focused on achieving the easiest fusion reaction, that between Deuterium and ...Tritium.
A bit later the Deuterium-He-3 reaction is discussed in detail.
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