Part of the problem is that the wavelength of a signal at 400 MHz and one at 700 MHz differ by almost a factor of two. Finding an antenna that's 1) resonant and 2) an efficient radiator at both of those frequencies will be difficult.
Why not use a thin layer of biodegradable oil as has been proposed to weaken hurricanes? That would prevent evaporation and cost a lot less, I'd imagine. I doubt the oil would cause problems since the water is likely drained from below the surface. The only downside is the possible damage to wildlife.
> I haven't worked in the nuclear industry either but at least I have engineering experience.
I'm not gonna complain, but I'd like to point out that just having 'engineering experience' doesn't make you an expert either.
> Nuclear tech is expensive. LFTR is probably going to be extra expensive. The economics of power generation do not favor nuclear power.
> Once-thru fuel cycles are the most cost-efficient.
> Prove to me that a LFTR design that meets regulations for nuclear safety is going to be cheaper than a comparable PWR.
Sometimes cost isn't the most important issue. Safety should be, and I think you'll agree that even the most recent PWR/BWR reactors have much more intrinsic safety in their designs than the old-school PWRs that have been running for 40+ years.
Look at solar power (something that I'm not really a fan of) - it used to be heinously expensive, but thru research into cell design and improvements in manufacturing, it's really come down in cost to where it's actually cost-effective in some situations.
> Once-thru fuel cycles are the most cost-efficient.
Yes, given that the waste is sitting, unprotected, in casks on-site. That's like an old-school coal power plant operator saying coal ash is cheap to dispose of - let's just blast it all over the surrounding counties. If you don't have to pay to dispose of it properly, then of course it's cheap.
> Deep geological storage is the safest way of dealing with waste.
No one has any idea where or how much building a facility to deal with all that wasted fuel will cost, and exactly how well it'll stay in containment for 10k years. The real answer to the waste issue is to not generate it in the first place, and what you do generate should have the actinides burned away to limit the half-lives to less than 1,000 years or so.
> No known material has been demonstrated to be capable of containing the LFTR salt over the long time periods required.
Again, I'm not wed to LFTRs or even MSR's - I'd be just as happy with a gaseous primary coolant. I want a strong negative void coefficient and other intrinsic safety features instead of the way we have it now. I want the physics to work for us, not against us.
It sounds like you and I are on the same page with regard to nuclear power - it's important, and needs to be a part of the solution. I say let's take the time and spend the money to start fresh and look at ideas that may have been discarded before but now may make sense. Let's also revamp the NRC - it's so caught up in regulatory capture with PWRs that it can't even begin to assess the safety of any other design.
"Everything I know about nuclear power, I learned from watching LFTR videos."
That's disingenuous - I've been following the nuclear power saga since the 70's. I majored in physics (ended up w/ a minor) and I've also been inside the control room and containment vessel of an actual commercial PWR and toured a couple of research swimming pool reactors.
LFTRs just happen to be the latest 'new old' idea that's been brought back to the fore. LFTRs may not be the wave of the future, and that's ok with me, but at least someone, somewhere is thinking out-of-the-box and is concerned about the viability of nuclear power beyond our rather over-complicated existing PWR's.
Once-thru fuel cycles, one-off designs, and using a high pressure phase changing primary coolant is just silly. We need to graduate to more sophisticated and more intrinsically safe designs. We don't still use carburetors in (most) cars - fuel injection is more efficient and cleaner. We don't use turbojet-only engines on jet aircraft, we use turbofans - again, much more efficient and cleaner. Nuclear power needs to have its own renaissance, preferably sooner than later.
You'd still need a huge containment building for your LFTR. Worse, it would need to contain not just the reactor core, but the fuel reprocessing system. It would probably be bigger, not smaller, than a PWR reactor building of equivalent power.
I'm not concerned with the physical size of the building, I'm concerned with keeping the 3000 PSI corrosive genie in the bottle. A building capable of withstanding a jet impact is a lot easier to build than one that also has to contain a flash-to-steam event.
The startup time of a large motor is just a couple of seconds, and as Figure 1 in this PDF shows, a typical breaker is made to withstand 6-20x its rated current for 3 seconds.
I'm not sure that was the implication. Box said that when the fish stopped coming he started preserving people instead. He kinda went nuts when his primary function was no longer needed - I don't think any of his corpsickles were actually eaten.
Thorium solves none of the problems we have with current fission reactors. I'm not even sure where to start - here's just one example.
If you watch the videos re: LFTRs, you'll see that most of the design of a conventional reactor is there to deal with the possibility of a primary coolant pressure loss and the resultant massive steam release. This is an enormous risk in all existing power plants. A LFTR runs at essentially atmospheric pressure and with no phase change, so there's no need for a massive high pressure containment vessel.
Here's my local power company's tariff. Under GS-2 non-demand billing, it looks like you'd pay 8.173 cents/kWh in the summer and 7.452 cents/kWh in the winter including all charges for generation, distribution, and transmission. There's a $21.17 monthly charge, so your 4000 kWh use case would be $348.09 in the summer and $319.25 in the winter here in the Old Dominion.
Demand billing gets you $342.71 summer, $285.19 winter.
I didn't do the math for Schedule 10, but that might be even cheaper.
I used to shoot skeet, too. Very enjoyable. I agree it was an unlikely shot, but we have empirical evidence of the outcome - he did shoot it down. The missing variables are the true distance to target and what load he was shooting. I'd say we have to wait and see if more information becomes available.
Fun chatting about shotguns - I might have to dust off the skeet launcher.
I get closer to 0.5 J, but still there are about 410 pellets to the oz, so for a standard 1.125 oz load that's a maximum of 461 pellets buzzing around, getting hit (hard!) by the props.
The whole 'water absorption' thing is mostly a myth. There is not a large absorption band at 2.4 GHz - that frequency was chosen specifically since it's in an ISM band where devices that generate and use RF for non-communications purposes are meant to live.
... illegally transmitting in restricted spectrum.
2.4 GHz is some of the _least_ restricted RF spectrum, FWIW.
Too bad I can't charge for using Amateur radio - I can legally transmit up to 1500W into the antenna on that band (2300-2450 MHz) with no restriction on Effective Isotropic Radiated Power. Here's a 1.0x0.6 m somewhat paraboloid antenna that has 24 dB gain in a 10x14 degree pattern, making the EIRP 377kW. I bet that would pop the radios in that drone.
(Naturally I'd never do this - according to RF exposure limits, that setup would exceed the limits for uncontrolled human exposure out to 180 feet or so).
Slashdot Mirror
Virginia only issues a Concealed Handgun Permit. It specifically does not apply to knives, etc.
That's only a 143% increase - it's 243% of the original value, however.
... microwave ovens work because they're tuned to the resonant frequency of water ...
Bzzt. Microwave ovens use 2.4GHz because there's an ISM band there. There is no resonance at 2.4 GHz for water. If there was your food would explode in the oven.
Part of the problem is that the wavelength of a signal at 400 MHz and one at 700 MHz differ by almost a factor of two. Finding an antenna that's 1) resonant and 2) an efficient radiator at both of those frequencies will be difficult.
Why not use a thin layer of biodegradable oil as has been proposed to weaken hurricanes? That would prevent evaporation and cost a lot less, I'd imagine. I doubt the oil would cause problems since the water is likely drained from below the surface. The only downside is the possible damage to wildlife.
> I haven't worked in the nuclear industry either but at least I have engineering experience.
I'm not gonna complain, but I'd like to point out that just having 'engineering experience' doesn't make you an expert either.
> Nuclear tech is expensive. LFTR is probably going to be extra expensive. The economics of power generation do not favor nuclear power.
> Once-thru fuel cycles are the most cost-efficient.
> Prove to me that a LFTR design that meets regulations for nuclear safety is going to be cheaper than a comparable PWR.
Sometimes cost isn't the most important issue. Safety should be, and I think you'll agree that even the most recent PWR/BWR reactors have much more intrinsic safety in their designs than the old-school PWRs that have been running for 40+ years.
Look at solar power (something that I'm not really a fan of) - it used to be heinously expensive, but thru research into cell design and improvements in manufacturing, it's really come down in cost to where it's actually cost-effective in some situations.
> Once-thru fuel cycles are the most cost-efficient.
Yes, given that the waste is sitting, unprotected, in casks on-site. That's like an old-school coal power plant operator saying coal ash is cheap to dispose of - let's just blast it all over the surrounding counties. If you don't have to pay to dispose of it properly, then of course it's cheap.
> Deep geological storage is the safest way of dealing with waste.
No one has any idea where or how much building a facility to deal with all that wasted fuel will cost, and exactly how well it'll stay in containment for 10k years. The real answer to the waste issue is to not generate it in the first place, and what you do generate should have the actinides burned away to limit the half-lives to less than 1,000 years or so.
> No known material has been demonstrated to be capable of containing the LFTR salt over the long time periods required.
Again, I'm not wed to LFTRs or even MSR's - I'd be just as happy with a gaseous primary coolant. I want a strong negative void coefficient and other intrinsic safety features instead of the way we have it now. I want the physics to work for us, not against us.
It sounds like you and I are on the same page with regard to nuclear power - it's important, and needs to be a part of the solution. I say let's take the time and spend the money to start fresh and look at ideas that may have been discarded before but now may make sense. Let's also revamp the NRC - it's so caught up in regulatory capture with PWRs that it can't even begin to assess the safety of any other design.
"Everything I know about nuclear power, I learned from watching LFTR videos."
That's disingenuous - I've been following the nuclear power saga since the 70's. I majored in physics (ended up w/ a minor) and I've also been inside the control room and containment vessel of an actual commercial PWR and toured a couple of research swimming pool reactors.
LFTRs just happen to be the latest 'new old' idea that's been brought back to the fore. LFTRs may not be the wave of the future, and that's ok with me, but at least someone, somewhere is thinking out-of-the-box and is concerned about the viability of nuclear power beyond our rather over-complicated existing PWR's.
Once-thru fuel cycles, one-off designs, and using a high pressure phase changing primary coolant is just silly. We need to graduate to more sophisticated and more intrinsically safe designs. We don't still use carburetors in (most) cars - fuel injection is more efficient and cleaner. We don't use turbojet-only engines on jet aircraft, we use turbofans - again, much more efficient and cleaner. Nuclear power needs to have its own renaissance, preferably sooner than later.
You'd still need a huge containment building for your LFTR. Worse, it would need to contain not just the reactor core, but the fuel reprocessing system. It would probably be bigger, not smaller, than a PWR reactor building of equivalent power.
I'm not concerned with the physical size of the building, I'm concerned with keeping the 3000 PSI corrosive genie in the bottle. A building capable of withstanding a jet impact is a lot easier to build than one that also has to contain a flash-to-steam event.
The startup time of a large motor is just a couple of seconds, and as Figure 1 in this PDF shows, a typical breaker is made to withstand 6-20x its rated current for 3 seconds.
IIRC the start capacitor doesn't store charge to help with startup current; rather it provides a phase shift in the aux winding to get the armature moving.
The 11 year old me had the same idea when that movie came out. Also, Farrah Fawcett - what a magnificent smile.
That product was featured on an episode of Unwrapped that I just happened to watch.
I'm not sure that was the implication. Box said that when the fish stopped coming he started preserving people instead. He kinda went nuts when his primary function was no longer needed - I don't think any of his corpsickles were actually eaten.
Thorium solves none of the problems we have with current fission reactors.
I'm not even sure where to start - here's just one example.
If you watch the videos re: LFTRs, you'll see that most of the design of a conventional reactor is there to deal with the possibility of a primary coolant pressure loss and the resultant massive steam release. This is an enormous risk in all existing power plants. A LFTR runs at essentially atmospheric pressure and with no phase change, so there's no need for a massive high pressure containment vessel.
Here's my local power company's tariff. Under GS-2 non-demand billing, it looks like you'd pay 8.173 cents/kWh in the summer and 7.452 cents/kWh in the winter including all charges for generation, distribution, and transmission. There's a $21.17 monthly charge, so your 4000 kWh use case would be $348.09 in the summer and $319.25 in the winter here in the Old Dominion.
Demand billing gets you $342.71 summer, $285.19 winter.
I didn't do the math for Schedule 10, but that might be even cheaper.
Slashdot ate his <.
I used to shoot skeet, too. Very enjoyable. I agree it was an unlikely shot, but we have empirical evidence of the outcome - he did shoot it down. The missing variables are the true distance to target and what load he was shooting. I'd say we have to wait and see if more information becomes available.
Fun chatting about shotguns - I might have to dust off the skeet launcher.
I get closer to 0.5 J, but still there are about 410 pellets to the oz, so for a standard 1.125 oz load that's a maximum of 461 pellets buzzing around, getting hit (hard!) by the props.
Two of those pellets have "the kinetic energy of a 56 g tennis ball moving at 6 m/s (22 km/h)". From the standpoint of a tiny, light drone, that's a lot of energy to absorb.
So do you want to be forced to use non-computer based solutions for your Title II-regulated phone systems? Be careful what you wish for, $MEGACORPS.
You'd think they were part of some hive mind or something.
E = 1/2 m v^2
That barrier is so big that it would likely take many, many times the age of the universe for the transition to occur.
No, it will take exactly one "age of the Universe" to tunnel and cause the collapse.
Here's one that claims 1460 W, so it's not _too_ far off base (look at the specs page).
I said "That's about 2 secs for an average microwave" meaning 2 secs x 1000 W is 2000 W-secs. I mixed up my units, I know.
Two petawatts for a picosecond is an average power of 2000W. That's about 2 secs for an average microwave, taking inefficiency into account.
The whole 'water absorption' thing is mostly a myth. There is not a large absorption band at 2.4 GHz - that frequency was chosen specifically since it's in an ISM band where devices that generate and use RF for non-communications purposes are meant to live.
... illegally transmitting in restricted spectrum.
2.4 GHz is some of the _least_ restricted RF spectrum, FWIW.
Too bad I can't charge for using Amateur radio - I can legally transmit up to 1500W into the antenna on that band (2300-2450 MHz) with no restriction on Effective Isotropic Radiated Power. Here's a 1.0x0.6 m somewhat paraboloid antenna that has 24 dB gain in a 10x14 degree pattern, making the EIRP 377kW. I bet that would pop the radios in that drone.
(Naturally I'd never do this - according to RF exposure limits, that setup would exceed the limits for uncontrolled human exposure out to 180 feet or so).
Maybe we can ask Andromeda's Secret what Victoria's Secret is.