> Id say nuclear power uses quite a lot more Uranium in comparison to other ways of generating electricity, considering those other ways don't use any Uranium at all...
Of course
> According to the World Nuclear Association [world-nuclear.org], nuclear power consumes about 200 tons of Uranium oxide per GWe per year.
Would that be before or after enrichement? Because in order to use uranium in anything except CANDU cycle, you need to throw away somewhere between 89% (3% enriched) and 99% (50% enriched for startup) or the original yellowcake.
The energy costs of enriching uranium are staggering - and that's quite apart from anything associated with mining it (as others have pointed out most of the time it's a byproduct of mining other materials)
As for China: The comments about uranium consumption assume it's planning on using uranium: It's still investing heavily in MSR Thorium research: Thorium doesn't need enrichment and there are hundreds of thousands of tons already available for use as it's a nuisance byproduct of rare earth mining.
Uranium is used in nuclear reactors because the first practical one used uranium and it used uranium because that was what was available, even through thorium would have been a better material for the job (none was available at the time). Alvin Weinberg moved on and made a Thorium reactor (molten salt) for his next party trick, but commercial industry had already taken the light water design and run with it despite its inherent dangers, so weren't interested in the much safer design and the military didn't want thorium reactors because the byproduct of uranium enrichment (depleted uranium) is an essential component of thermonuclear bombs.
Yup, When I was working in the deployment of AMPS in New Zealand in the 1980s, we were able to work 20W cellsites in Wellington from the skifields at Turoa (about 150 miles away and sited at about 300feet AMSL) with a 3W bagphone and unmodified antenna. Being at ~4500 feet AMSL and having a clear line of sight helped.
We could trivially pick up 100W FM stations at that distance too.
"One covers a town of about 2000 people that sits in a valley that has no FM radio reception the than my station (not even PBS/NPR).
Another is a radio station that gives news in Vietnamese so that they have a native language option."
In a lot of countries there are specific microbroadcast options for 100mW (no license required), 1W (no license required if operating in the guardbands) on non-interference basis, and 5-10W on fast-track basis using isotropic radiators.
It sounds like the real problem is that the regulatory framework is 30 years behind the times.
LinkedIn are spammers. I've never been on it and I get 10-20 "Invitations" a month - that's despite living in countries with laws about data privacy and spam.
"I can't think of a time when simply not showing up any more would be considered acceptable behaviour"
Desperately clinging onto jobs comes with economic privation. The USA has been a buyer's (employer's) market for a long time and people have forgotten what it's like to be the other way around - which also comes with decent pay and conditions.
"The HR person lectured me that it was their one and only offer, they would not negotiate and that I was to tell the third party recruiter who connected us that their would be no negotiation."
In other words the "HR person" attempted to bully you into submission and to do so in a way that would allow them to weasel out of whatever contract they has with the recruiter.
The problem with using fuel cells in cars isn't the fuel cells. It's the fuel storage.
Home fuel cells are easy. You can pipe natural gas at low pressure to your house and crack it as needed with no real problem.
When you start putting hydrogen (or natural gas) in tanks at high pressure, you get problems due to the pressure cycling (think "Tank rupture") along with embritlement and in the case of hydrogen it's hard to keep _in_ the tank over a prolonged period.
Hydrogen is a "gee whiz" technology, but trhe reality is that no maker has ever sold a hydrogen powered car due to the liability issues arising if owners don't rigidly maintain them in the case of pressurised tanks. LH2 is impractical (it's hard enough to handle in stationary applications) and whilst metal hydrides are safe, they're so expensive that you'd end up with the fuel tank costing more than the rest of the car, so noone would buy them.
"we already can accurately forecast that when we can build a fusion reactor that uses that easiest to burn D-T fuel it will not be able to compete with any commercial source of electricity."
Remove carbon-emitting sources from the equation and run that competition again. Include anything burning wood in that "carbon emitting" list, because it's likely that we're going to be frantically planting them to generate enough oxygen to actually survive in the face of oceanic oxygen sources going away..
1: There's a LOT of thorium already waiting to be used. It's an annoying byproduct of rare earth minining, to the tune of somewhere between 20-100,000 tons per year. The USA DOE buried several tens of thousands of tons of the stuff in the Utah desert because they couldn't get rid of it.
2: Thorium designs already exist, have already been proven in trials and don't suffer from the scaling problems of PWR systems (ie, you don't end up with a massive radioactive steam bomb). Recreating them will take far less time than mastering the basic science of fusion, but there's not much profit in a system where the fuel is liquid and vendors don't hold lock-in for the life of the reactor as they do with PWR/BWR designs (fuel rods are proprietary shapes and not interchangeable between suppliers)
3: the reason there's no Thorium and MSR research happening in the USA is because it's specifically illegal in the USA. You can thank Richard Milhous Nixon for that. Oak Ridge is researching non-nuclear aspects of molten salts but they can't fire up a reactor again.
"You mean the country which has a 7% YoY increase in energy production over the past 10 years compared to America's 0.05%? "
It's worth pointing out that just about every historic economy has been driven by access to cheap energy. In the old days it was slaves, water and wind. More recently it was coal, then oil and gas and now we're chasing other major energy sources, (electricity is a transmission medium, not a source)
Whilst _I_ won't be around to see it, I doubt that fusion will be commercially viable in the lifetimes of the grandchildren of anyone alive today.
As for the current fission reactor mess, if Nixon hadn't killed MSR research 45 years ago we'd be a lot better off than we are today but it can still be turned around and with the potential looming ecological crisis (global warming/climate change is "best case scenarios" and looking increasingly unlikely, vs anoxic events and food chain collapse) there's likely to be a lot of pressure to make it work.
In most cases, knowing where an asteroid will hit means that the best policy will be evacuation/preparedness.
Breaking an asteroid or comet up may actually be _worse_ than having a single impactor, especially for glancing blows - a chap named "craterhunter" has been researching the hypothesis that an airbursting fragmented comet was responsible for sterilising most of North American circa 10k years ago and triggering the Younger Dryas, without leaving much in the way of impact craters. Simulating what happens when multiple fragments hit the upper atmosphere tends to support his idea that they effectively punch a plasma fireball to the ground in a similar matter to the way a shaped charge HEAT round penetrates tank armour.
It's hard to see things coming towards us from the direction of the asteroid belt - and virtually impossible to see them when they're coming from the direction of the sun. Almost everything orbiting can be described as "blacker than a black cat in a coal mine at midnight", so we tend to only see them as they whip past.
"It makes no sense to refer to our descendants 5 billion years from now, as "we", let alone worry about their fate."
It makes no sense to consider that we would have decendants on _this_ planet 5 billion years from now.
In around 500 million years the sun will have become hot enough that earth will be too hot for life to exist here (except maybe deep underground). It's already 50% brighter than it was 500 million years ago.
"We're omnivores at the top of the food chain - we won't die out until there's no other life left to eat."
We may be omnivores, but we have extremely oxygen-hungry brains.
The most likely planetary event in the near future is an anoxic event - caused by us - and we're likely to be the first major casualty of it.
There's only one ethnic group that can handle a long-term reduction in sea-level oxygen concentration to 17% or below and they currently mostly live above 8000 feet - Tibetans/Nepalese(*). Even then they'd have to move to sea level and I suspect that as half our atmospheric oxygen comes from the oceans there's a good chance that the percentage may go below 15%, which even that population would have trouble coping with.
30 years ago someone postulated that in 50,000 years our descendants would probably be oxygen starved apes living in coastal swamps covering what remained of our cities. That hypothesis may well be right.
On the bright side, an anoxic event would eventually take out most critters larger than about 25kg, and anoxic events lay down oil deposits - which means that in about 60 million years another intelligent species might evolve have a chance to try for spaceflight again.
(*) Humans (and most primates) cope with reduced oxygen levels by thickening their blood coupled with vasodilation. This works as a temporary measure but the (not very) long term effect is congestive pulmonary failure due to the extra pumping load (High altitude pulmonary oedema (HAPE) - which can come on after only a few days, along with high altitude cerebral edema (HACE)). The two groups above have a genetic variant which increases the oxygen carrying capacity of their blood without making it harder to circulate.
That influence has been around almost forever. SW was classic space/horse opera in the 1930-40s mould. Ep1 was even truer to that paradigm than ep4 complete with "yellow peril" (which was an artifact of the first Cold War - with Japan)
Farming out email to a 3rd party (or not offering email at all) won't reduce your email-related support calls.
You're an ISP, people expect to phone up for assistance with intenet problems even if you're not the provider of the actual service in question - and if you can't assist them they're likely to take their entire business elsewhere.
As an ISP in the 1990s we made a lot of business offering email support for people who weren't our customers and won over a lot of dial-in accounts as a result.
Of course eventually the telcos rolled in like 9000-pound gorillas and wiped out the small outfits but the principle is the same, especially in markets where there are multiple providers.
Slashdot Mirror
"Yes, it's the total emissions including all the mining and fuel transport and storage and air conditioning for the control room etc. etc."
None of that is worth a damn compared to the enrichment costs - and those are classified.
> Id say nuclear power uses quite a lot more Uranium in comparison to other ways of generating electricity, considering those other ways don't use any Uranium at all...
Of course
> According to the World Nuclear Association [world-nuclear.org], nuclear power consumes about 200 tons of Uranium oxide per GWe per year.
Would that be before or after enrichement? Because in order to use uranium in anything except CANDU cycle, you need to throw away somewhere between 89% (3% enriched) and 99% (50% enriched for startup) or the original yellowcake.
The energy costs of enriching uranium are staggering - and that's quite apart from anything associated with mining it (as others have pointed out most of the time it's a byproduct of mining other materials)
As for China: The comments about uranium consumption assume it's planning on using uranium: It's still investing heavily in MSR Thorium research: Thorium doesn't need enrichment and there are hundreds of thousands of tons already available for use as it's a nuisance byproduct of rare earth mining.
Uranium is used in nuclear reactors because the first practical one used uranium and it used uranium because that was what was available, even through thorium would have been a better material for the job (none was available at the time). Alvin Weinberg moved on and made a Thorium reactor (molten salt) for his next party trick, but commercial industry had already taken the light water design and run with it despite its inherent dangers, so weren't interested in the much safer design and the military didn't want thorium reactors because the byproduct of uranium enrichment (depleted uranium) is an essential component of thermonuclear bombs.
"Ham radio is only practical because it's utterly useless"
On the contrary, ham radio is useful for its intended purpose - education, experimentation and research into technologies.
Hams are supposed to be pushing the boundaries of what's possible.
"Antenna height matters more than output power."
Yup, When I was working in the deployment of AMPS in New Zealand in the 1980s, we were able to work 20W cellsites in Wellington from the skifields at Turoa (about 150 miles away and sited at about 300feet AMSL) with a 3W bagphone and unmodified antenna. Being at ~4500 feet AMSL and having a clear line of sight helped.
We could trivially pick up 100W FM stations at that distance too.
"One covers a town of about 2000 people that sits in a valley that has no FM radio reception the than my station (not even PBS/NPR).
Another is a radio station that gives news in Vietnamese so that they have a native language option."
In a lot of countries there are specific microbroadcast options for 100mW (no license required), 1W (no license required if operating in the guardbands) on non-interference basis, and 5-10W on fast-track basis using isotropic radiators.
It sounds like the real problem is that the regulatory framework is 30 years behind the times.
"I've been plagued by recruiters on^W^W LinkedIn"
There, fixed it for you.
LinkedIn are spammers. I've never been on it and I get 10-20 "Invitations" a month - that's despite living in countries with laws about data privacy and spam.
"I can't think of a time when simply not showing up any more would be considered acceptable behaviour"
Desperately clinging onto jobs comes with economic privation. The USA has been a buyer's (employer's) market for a long time and people have forgotten what it's like to be the other way around - which also comes with decent pay and conditions.
"The HR person lectured me that it was their one and only offer, they would not negotiate and that I was to tell the third party recruiter who connected us that their would be no negotiation."
In other words the "HR person" attempted to bully you into submission and to do so in a way that would allow them to weasel out of whatever contract they has with the recruiter.
Not the kind of employer I'd like to work for.
Employers have been doing it to potential employees for decades. Now the boot's on the other foot.
The problem with using fuel cells in cars isn't the fuel cells. It's the fuel storage.
Home fuel cells are easy. You can pipe natural gas at low pressure to your house and crack it as needed with no real problem.
When you start putting hydrogen (or natural gas) in tanks at high pressure, you get problems due to the pressure cycling (think "Tank rupture") along with embritlement and in the case of hydrogen it's hard to keep _in_ the tank over a prolonged period.
Hydrogen is a "gee whiz" technology, but trhe reality is that no maker has ever sold a hydrogen powered car due to the liability issues arising if owners don't rigidly maintain them in the case of pressurised tanks. LH2 is impractical (it's hard enough to handle in stationary applications) and whilst metal hydrides are safe, they're so expensive that you'd end up with the fuel tank costing more than the rest of the car, so noone would buy them.
Labour costs aren't much cheaper in asia. The win is in logistics.
"we already can accurately forecast that when we can build a fusion reactor that uses that easiest to burn D-T fuel it will not be able to compete with any commercial source of electricity."
Remove carbon-emitting sources from the equation and run that competition again. Include anything burning wood in that "carbon emitting" list, because it's likely that we're going to be frantically planting them to generate enough oxygen to actually survive in the face of oceanic oxygen sources going away..
1: There's a LOT of thorium already waiting to be used. It's an annoying byproduct of rare earth minining, to the tune of somewhere between 20-100,000 tons per year. The USA DOE buried several tens of thousands of tons of the stuff in the Utah desert because they couldn't get rid of it.
2: Thorium designs already exist, have already been proven in trials and don't suffer from the scaling problems of PWR systems (ie, you don't end up with a massive radioactive steam bomb). Recreating them will take far less time than mastering the basic science of fusion, but there's not much profit in a system where the fuel is liquid and vendors don't hold lock-in for the life of the reactor as they do with PWR/BWR designs (fuel rods are proprietary shapes and not interchangeable between suppliers)
3: the reason there's no Thorium and MSR research happening in the USA is because it's specifically illegal in the USA. You can thank Richard Milhous Nixon for that. Oak Ridge is researching non-nuclear aspects of molten salts but they can't fire up a reactor again.
"You mean the country which has a 7% YoY increase in energy production over the past 10 years compared to America's 0.05%? "
It's worth pointing out that just about every historic economy has been driven by access to cheap energy. In the old days it was slaves, water and wind. More recently it was coal, then oil and gas and now we're chasing other major energy sources, (electricity is a transmission medium, not a source)
Whilst _I_ won't be around to see it, I doubt that fusion will be commercially viable in the lifetimes of the grandchildren of anyone alive today.
As for the current fission reactor mess, if Nixon hadn't killed MSR research 45 years ago we'd be a lot better off than we are today but it can still be turned around and with the potential looming ecological crisis (global warming/climate change is "best case scenarios" and looking increasingly unlikely, vs anoxic events and food chain collapse) there's likely to be a lot of pressure to make it work.
In most cases, knowing where an asteroid will hit means that the best policy will be evacuation/preparedness.
Breaking an asteroid or comet up may actually be _worse_ than having a single impactor, especially for glancing blows - a chap named "craterhunter" has been researching the hypothesis that an airbursting fragmented comet was responsible for sterilising most of North American circa 10k years ago and triggering the Younger Dryas, without leaving much in the way of impact craters. Simulating what happens when multiple fragments hit the upper atmosphere tends to support his idea that they effectively punch a plasma fireball to the ground in a similar matter to the way a shaped charge HEAT round penetrates tank armour.
"Actually we are looking, just not very well."
It's hard to see things coming towards us from the direction of the asteroid belt - and virtually impossible to see them when they're coming from the direction of the sun. Almost everything orbiting can be described as "blacker than a black cat in a coal mine at midnight", so we tend to only see them as they whip past.
"It makes no sense to refer to our descendants 5 billion years from now, as "we", let alone worry about their fate."
It makes no sense to consider that we would have decendants on _this_ planet 5 billion years from now.
In around 500 million years the sun will have become hot enough that earth will be too hot for life to exist here (except maybe deep underground). It's already 50% brighter than it was 500 million years ago.
"We're omnivores at the top of the food chain - we won't die out until there's no other life left to eat."
We may be omnivores, but we have extremely oxygen-hungry brains.
The most likely planetary event in the near future is an anoxic event - caused by us - and we're likely to be the first major casualty of it.
There's only one ethnic group that can handle a long-term reduction in sea-level oxygen concentration to 17% or below and they currently mostly live above 8000 feet - Tibetans/Nepalese(*). Even then they'd have to move to sea level and I suspect that as half our atmospheric oxygen comes from the oceans there's a good chance that the percentage may go below 15%, which even that population would have trouble coping with.
30 years ago someone postulated that in 50,000 years our descendants would probably be oxygen starved apes living in coastal swamps covering what remained of our cities. That hypothesis may well be right.
On the bright side, an anoxic event would eventually take out most critters larger than about 25kg, and anoxic events lay down oil deposits - which means that in about 60 million years another intelligent species might evolve have a chance to try for spaceflight again.
(*) Humans (and most primates) cope with reduced oxygen levels by thickening their blood coupled with vasodilation. This works as a temporary measure but the (not very) long term effect is congestive pulmonary failure due to the extra pumping load (High altitude pulmonary oedema (HAPE) - which can come on after only a few days, along with high altitude cerebral edema (HACE)). The two groups above have a genetic variant which increases the oxygen carrying capacity of their blood without making it harder to circulate.
> the 'space western' influence
That influence has been around almost forever. SW was classic space/horse opera in the 1930-40s mould. Ep1 was even truer to that paradigm than ep4 complete with "yellow peril" (which was an artifact of the first Cold War - with Japan)
It's called "noble cause corruption" - and it's right through the NZ structure.
" we had one guy that absolutely assumed the guy was guilty precisely because he was arrested"
Last time I was on Jury duty 8 of the jurors were like that and 2 more just wanted to go home.
Farming out email to a 3rd party (or not offering email at all) won't reduce your email-related support calls.
You're an ISP, people expect to phone up for assistance with intenet problems even if you're not the provider of the actual service in question - and if you can't assist them they're likely to take their entire business elsewhere.
As an ISP in the 1990s we made a lot of business offering email support for people who weren't our customers and won over a lot of dial-in accounts as a result.
Of course eventually the telcos rolled in like 9000-pound gorillas and wiped out the small outfits but the principle is the same, especially in markets where there are multiple providers.
the difference being that you can't patent "laws of nature" but you can patent novel applications for USING those laws of nature.
To quote Samuel Clemens:
"The opposite of progress is Congress"