PS - Thanks to the hard work done by the ARRL and others, amateur radio operators worldwide* will be getting a new MF band at 630m or 472-479 kHz (just below Broadcast AM radio). It's only 7 kHz wide (enough for 2-3 simultaneous SSB voice conversations). Lots of experimentation potential - now we'll see how Joe Taylor's excellent digital modes handle the unique propagation issues in that band.
You dismiss the presenter as a talking head - I think he deserves a little more respect as he does have meaningful credentials. His name is Kirk Sorensen, and wikipedia says he "... has a bachelor's degree in mechanical engineering from Utah State University, a master's degree in aerospace engineering from the Georgia Institute of Technology, and is currently pursuing a master's degree in nuclear engineering at the University of Tennessee. He worked at NASA's Marshall Space Flight Center from 2000 to 2010, followed by a year at Teledyne Brown Engineering in Huntsville, Alabama as Chief Nuclear Technologist until he left to found Flibe Energy in 2011."
IIRC, he was tasked with designing a moon colony for NASA and had to come up with a power source capable of operating safely within the confines of a small community and with limited refueling/interaction. That's where his version of the LFTR came from.
You may have missed one or two of the main technical points of this setup.
1) The reactor is fueled and 'waste' is extracted continuously using already well-understood chemistry - no fueling downtime. 2) The LFTR can burn our current nuclear waste ridding us of the nasty actinides that make the current 'waste' dangerous for long periods of time. 3) It can also burn the 'Killstoff' of which we now have an overabundance 4) Many of the extracted 'waste' products from the LFTR are actually useful metals/isotopes - medical isotopes, isotopes for RTGs, etc.
Also, a word on 'forever' - yes, he may have been using a bit of hyperbole, but as compared to other non-solar-derived energy sources, 'forever' may actually be close to the correct word.
Energy from Thorium states that "A mere 6,600 tonnes of thorium could provide the energy equivalent of the combined [annual] global consumption of 5 billion tonnes of coal, 31 billion barrels of oil, 3 trillion cubic meters of natural gas, and 65,000 tonnes of uranium. With LFTR, a handful of thorium can supply an individual’s lifetime energy needs; a grain silo full could power North America for a year; and known thorium reserves could power advanced society for many thousands of years."
According to estimates, there are somewhere between 1.9 and 2.8 million tonnes of Thorium economically available right now - that's economically available with no use whatsoever for Thorium! The total crustal Thorium content is estimated at 120 trillion tonnes.
From the same article:
In event of a thorium fuel cycle, Conway granite with 56 (+-6) parts per million thorium could provide a major low-grade resource; a 307 sq mile (795 sq km) "main mass" in New Hampshire is estimated to contain over three million metric tons per 100 feet (30 m) of depth (i.e. 1 kg thorium in eight cubic metres of rock), of which two-thirds is "readily leachable". Even common granite rock with 13 PPM thorium concentration (just twice the crustal average, along with 4 ppm uranium) contains potential nuclear energy equivalent to 50 times the entire rock's mass in coal, although there is no incentive to resort to such very low-grade deposits so long as much higher-grade deposits remain available and cheaper to extract. Thorium has been produced in excess of demand from the refining of rare earth elements.
So if we were to start actually having a use for Thorium, chewing up plain old granite would yield 50x the energy of coal. If we could only tap 10% of the crustal supply, we'd have a 1.8 billion year total energy consumption supply (not just electricity) at current consumption. As far as societies and species go, that may as well be forever.
Won't that (running your coolant at atmospheric pressure) be atrocious for thermodynamic efficiency? For maximum efficiency you want as high a temperature difference as possible between your starting and final states. Which is the main reason for running steam generators for power plants in the supercritical state.
The primary coolant (the one that's running thru the core and is nuclear-hot) does not need to run at high pressure for thermodynamic efficiency. We're talking a molten salt here - it runs at 700 C at atmospheric pressure. According to this section on LFTRs, you could get 45% thermal to electrical efficiency using a standard Rankine cycle turbine. Note that existing PWR/BWRs max out at 36%. You can also use Brayton cycle turbines to eliminate water/steam from the equation.
Please take the time to watch the video I linked to. If you're at all into technology, it's worth the time.
The real mind-bender comes when you realize it doesn't have to be your car - auto-driving cars will become interchangeable like taxis. Instead of calling for your car to come get you after the meeting, you simply call for the nearest car that fits your needs to come get you.
...you might have to walk a few hundred yards to a bus stop.
You must live in Europe or a big US city. The nearest bus stop to my house is 8.3 MILES from my house and it's then an additional 4.3 mile bus ride to the office. It's only 10.4 miles from my house to the office directly.
I agree. We should be working _hard_ to wean ourselves off of fossil fuels ASAP for a whole multitude of reasons. Just this morning one of the talking heads asked Warren Buffett if we should invest in upgrading our infrastructure now, while we need the jobs. I say we should immediately begin the process of upgrading the electrical transmission system to handle the load of an essentially all-electric society and get to designing and building standard LFTR reactors to provide the electricity _and_ burn the worst of the existing nuclear 'waste' (that still has 98% of its original energy still present).
Most people think LFTRs need water cooling - they do not. They can be built anywhere without the need for huge cooling towers and enormous containment buildings (running at atm pressure means no need to contain the primary coolant flashing to steam).
I guess it would be similar to winning a Nobel Peace Prize by running an experiment in 'peace' by a president with a kill list and an apparent case of latent bloodlust.
"would you switch over to solar if the cost was close to the same as you pay for energy today?"
Your question also has a slant - that cost is the only concern in switching to solar. If you're talking solar on their house, you omit the parts about the ugly panels, the batteries required, the cost of and maintenance on the panels and batteries, etc. If you're talking utility-provided solar, then there's the issue of great swaths of land covered in solar cells, the cost to the utility to convert, building-sized batteries or pumped-storage facilities that have to be build/maintained, etc.
My point is there's no easy way to ask a one sentence question for complicated issues like this.
I'm actually _less_ disturbed by the possible human toxicity of GM foods that I am by the lack of information on the potential negative impact on the rest of the environment by these cross-Domain genes being deployed in the wild.
The new ultra-low sulfur diesel is not as bad as the old #2 furnace oil that sooted and stank like crazy, but now you have to carry around a tank of goat piss.
I agree with your stance on everything except this point: A position of zero tolerance for risk, especially for existential issues such as energy, is a luxury we can no longer afford.
A position of zero tolerance for risk, especially for existential issues such as energy, is a fallacy, an impossibility, and has never existed and is not obtainable. FTFY
See Flight Options. I see their Phenoms and Citation Xs screaming by at 45,000ft on FlightRadar 24 (you can set a filter for callsign 'OPT' to see just their planes).
PS - The video Trinity and Beyond is a chilling yet enthralling science documentary of the [mostly US but some USSR] nuclear bomb programs. You might ask your students to guess how many bombs were set off in testing, and where. Give them this Google Earth KML and show them all of the places and yields.
The Mars Trilogy is interesting, and it might be an interesting exercise to have them outline what parts (both technical and social) are currently possible, which might be possible in 10 years, and which are pure fiction.
Also, the "Connections" series by James Burke (also available in video form) are an interesting way of showing how technology evolves from need. You might have your students look at a few of them and then identify a current need and predict a few possible technological advances that may come of it.
When the RPi came out, I was disappointed that it didn't have on-board flash. Since using them in a bunch of projects, however, my opinion has flip-flopped.
Does this new Beagle-board have the option to boot from the external flash card, or must it boot from the on-board flash? TFA says "The flash frees the microSD slot for storage or loading alternate OSes..." but does load mean boot or just that you can mount the flash drive and copy files over?
I _like_ the fact that the identity and configuration of my RPi's are fully contained on the external flash - I can back up everything about a particular system by yanking out the flash card and copying it. I can even swap hardware with zero configuration - the boards are identical and interchangeable (plus or minus the Ethernet address).
Slashdot Mirror
PS - Thanks to the hard work done by the ARRL and others, amateur radio operators worldwide* will be getting a new MF band at 630m or 472-479 kHz (just below Broadcast AM radio). It's only 7 kHz wide (enough for 2-3 simultaneous SSB voice conversations). Lots of experimentation potential - now we'll see how Joe Taylor's excellent digital modes handle the unique propagation issues in that band.
*for most values of worldwide
Here's the 2011 version of that chart.
...the same as did/do the PRC...
Why did you use an italic 'L' there? Oh...
You dismiss the presenter as a talking head - I think he deserves a little more respect as he does have meaningful credentials. His name is Kirk Sorensen, and wikipedia says he "... has a bachelor's degree in mechanical engineering from Utah State University, a master's degree in aerospace engineering from the Georgia Institute of Technology, and is currently pursuing a master's degree in nuclear engineering at the University of Tennessee. He worked at NASA's Marshall Space Flight Center from 2000 to 2010, followed by a year at Teledyne Brown Engineering in Huntsville, Alabama as Chief Nuclear Technologist until he left to found Flibe Energy in 2011."
IIRC, he was tasked with designing a moon colony for NASA and had to come up with a power source capable of operating safely within the confines of a small community and with limited refueling/interaction. That's where his version of the LFTR came from.
You may have missed one or two of the main technical points of this setup.
1) The reactor is fueled and 'waste' is extracted continuously using already well-understood chemistry - no fueling downtime.
2) The LFTR can burn our current nuclear waste ridding us of the nasty actinides that make the current 'waste' dangerous for long periods of time.
3) It can also burn the 'Killstoff' of which we now have an overabundance
4) Many of the extracted 'waste' products from the LFTR are actually useful metals/isotopes - medical isotopes, isotopes for RTGs, etc.
Also, a word on 'forever' - yes, he may have been using a bit of hyperbole, but as compared to other non-solar-derived energy sources, 'forever' may actually be close to the correct word.
Energy from Thorium states that "A mere 6,600 tonnes of thorium could provide the energy equivalent of the combined [annual] global consumption of 5 billion tonnes of coal, 31 billion barrels of oil, 3 trillion cubic meters of natural gas, and 65,000 tonnes of uranium. With LFTR, a handful of thorium can supply an individual’s lifetime energy needs; a grain silo full could power North America for a year; and known thorium reserves could power advanced society for many thousands of years."
According to estimates, there are somewhere between 1.9 and 2.8 million tonnes of Thorium economically available right now - that's economically available with no use whatsoever for Thorium! The total crustal Thorium content is estimated at 120 trillion tonnes.
From the same article:
So if we were to start actually having a use for Thorium, chewing up plain old granite would yield 50x the energy of coal. If we could only tap 10% of the crustal supply, we'd have a 1.8 billion year total energy consumption supply (not just electricity) at current consumption. As far as societies and species go, that may as well be forever.
They've already done an awful lot of the engineering for molten salt reactors - and had a few actually running back in the 50's/60's!
The primary coolant (the one that's running thru the core and is nuclear-hot) does not need to run at high pressure for thermodynamic efficiency. We're talking a molten salt here - it runs at 700 C at atmospheric pressure. According to this section on LFTRs, you could get 45% thermal to electrical efficiency using a standard Rankine cycle turbine. Note that existing PWR/BWRs max out at 36%. You can also use Brayton cycle turbines to eliminate water/steam from the equation.
Please take the time to watch the video I linked to. If you're at all into technology, it's worth the time.
The real mind-bender comes when you realize it doesn't have to be your car - auto-driving cars will become interchangeable like taxis. Instead of calling for your car to come get you after the meeting, you simply call for the nearest car that fits your needs to come get you.
...you might have to walk a few hundred yards to a bus stop.
You must live in Europe or a big US city.
The nearest bus stop to my house is 8.3 MILES from my house and it's then an additional 4.3 mile bus ride to the office. It's only 10.4 miles from my house to the office directly.
Aka 'Purple Drank' and 'Sizzurp'. That stuff killed a lot of its early proponents. The original recipe contained codeine and promethazine, not DXM.
Awesome. You know it would probably sell if you put a Star Trek TOS insignia on the statue's judicial robe.
I agree. We should be working _hard_ to wean ourselves off of fossil fuels ASAP for a whole multitude of reasons. Just this morning one of the talking heads asked Warren Buffett if we should invest in upgrading our infrastructure now, while we need the jobs. I say we should immediately begin the process of upgrading the electrical transmission system to handle the load of an essentially all-electric society and get to designing and building standard LFTR reactors to provide the electricity _and_ burn the worst of the existing nuclear 'waste' (that still has 98% of its original energy still present).
Most people think LFTRs need water cooling - they do not. They can be built anywhere without the need for huge cooling towers and enormous containment buildings (running at atm pressure means no need to contain the primary coolant flashing to steam).
Give me control of the Spice and I'll control the universe.
Harrumph. I believe that _my_ line.
I guess it would be similar to winning a Nobel Peace Prize by running an experiment in 'peace' by a president with a kill list and an apparent case of latent bloodlust.
"would you switch over to solar if the cost was close to the same as you pay for energy today?"
Your question also has a slant - that cost is the only concern in switching to solar. If you're talking solar on their house, you omit the parts about the ugly panels, the batteries required, the cost of and maintenance on the panels and batteries, etc. If you're talking utility-provided solar, then there's the issue of great swaths of land covered in solar cells, the cost to the utility to convert, building-sized batteries or pumped-storage facilities that have to be build/maintained, etc.
My point is there's no easy way to ask a one sentence question for complicated issues like this.
Or Muad'Dave....
They've tried this in several areas, including the Cayman Islands.
From the linked article: "...there had already been an 80% decrease in the mosquito population as compared to adjacent control areas."
I'm actually _less_ disturbed by the possible human toxicity of GM foods that I am by the lack of information on the potential negative impact on the rest of the environment by these cross-Domain genes being deployed in the wild.
The new ultra-low sulfur diesel is not as bad as the old #2 furnace oil that sooted and stank like crazy, but now you have to carry around a tank of goat piss.
I agree with your stance on everything except this point: A position of zero tolerance for risk, especially for existential issues such as energy, is a luxury we can no longer afford.
A position of zero tolerance for risk, especially for existential issues such as energy, is a fallacy, an impossibility, and has never existed and is not obtainable.
FTFY
See Flight Options. I see their Phenoms and Citation Xs screaming by at 45,000ft on FlightRadar 24 (you can set a filter for callsign 'OPT' to see just their planes).
PS - The video Trinity and Beyond is a chilling yet enthralling science documentary of the [mostly US but some USSR] nuclear bomb programs. You might ask your students to guess how many bombs were set off in testing, and where. Give them this Google Earth KML and show them all of the places and yields.
The Mars Trilogy is interesting, and it might be an interesting exercise to have them outline what parts (both technical and social) are currently possible, which might be possible in 10 years, and which are pure fiction.
Also, the "Connections" series by James Burke (also available in video form) are an interesting way of showing how technology evolves from need. You might have your students look at a few of them and then identify a current need and predict a few possible technological advances that may come of it.
Thanks for the info! That's a good design.
Thanks for the info!
When the RPi came out, I was disappointed that it didn't have on-board flash. Since using them in a bunch of projects, however, my opinion has flip-flopped.
Does this new Beagle-board have the option to boot from the external flash card, or must it boot from the on-board flash? TFA says "The flash frees the microSD slot for storage or loading alternate OSes ..." but does load mean boot or just that you can mount the flash drive and copy files over?
I _like_ the fact that the identity and configuration of my RPi's are fully contained on the external flash - I can back up everything about a particular system by yanking out the flash card and copying it. I can even swap hardware with zero configuration - the boards are identical and interchangeable (plus or minus the Ethernet address).
Mars needs guitars
"'Cause the man from Mars stopped eatin' cars and eatin' bars and now he only eats guitars"
See this video at 3:47.