Yes, of course hydro and wind will work at night as well as in the day. But there simply isn't enough wind or hydro power to run places like the US northeast. Where there's hydro, it should be used. I think Oregon is like 80% hydro right now. Awesome, but that only works in isolated areas. Solar, on the other hand, probably brings enough power even to the US northeast if you can capture enough of it. But then you have to worry about storing it. that's what I was talking about.
Really? Can we just up and power the USA through the night with wind, solar, and hydro? I think not. These sources are intermittent. We either need baseload 24/7 reliable power or an incredible amount of energy storage. How much storage you ask? If you assume 100% efficient pulleys, you'd have to lift 44 fully loaded Nimitz class aircraft carriers (100,000 MT) to the top of the Burj Dubai (818m) and slowly let them down, turning a turbine throughout the night (9hours) to replace a single large power plant (1GW) for 1 night. To power the whole country through a night, we'd have to lift and drop 22,000 of them daily. The scale of this problem cannot be tackled by the intermittent renewables alone by any stretch of the imagination. We need to augment solar, wind, and hydro with nuclear power and plug-in hybrids. Cool.
For calculational details and a pic of 44 aircraft carriers on top of the Burj Dubai, see this page [whatisnuclear.com]
Surely a chemical explosion of 5kT would be detonated by multiple detonators. But to get that much power, you literally need a large room full of explosives. You can never reach the signature of nuclear devices with chemicals.
We had a departmental meeting about this the other day where a bunch of nuclear engineering professors got together and discussed what they thought had happened. The concensus was that this was actually a nuclear device. Almost definately. The seismic signals are the giveaway, and here's why. When a pile of chemicals explodes, they explode on a timescale of the speed of sound. So, the seismic signal from the explosion would be on the order of micro- to milli-seconds. When a nuclear device explodes, it happens in the time it takes for fast neutrons (>200keV) to get across a few centimeters. Now we're talking about nanoseconds. The seismic people have enough experience looking at explosions to be able to tell chemical from nuclear, and this one apparently looks nuclear.
It also looks to be 0.5kT or so. That makes it by far the smallest yield 1st test ever. Which either means they have perfected making small bombs (which is incredibly complicated and wasn't done by the Los Alamos people until 15 years after their first test), or they failed in their test. The latter is very likely. They've also wasted a lot of Pu-239 or U-235 (probably Pu) and contaminated their expensive underground test facility. Lets count the days together to see how long they take to test again. If it's quick, they have plenty of material. Only time will tell.
While it is true that at the supply of cheap fissile Uranium-235 (the fuel for conventional nuclear reactors) could possibly run out within 50-100 years, options such as fast breeder reactors and thorium-based fuel cycles have the capability to continue fueling conventional reactors for hundreds of years. The advanced reactors can run on abundant resources while producing excess fissile material. They actually produce more fuel than they burn. They also can process spent fuel (nuclear waste), converting most of it into usable fuel and the rest of it to a form that will only be of concern for 500 years as opposed to 100s of thousands. The advanced reactors could produce enough electricity using only the accumulated nuclear waste in the USA to power the whole country for at least 200 years. That's something worth looking into.
Believe it or not, but George Bush has already proposed and funded the Global Nuclear Energy Partnership (GNEP), which utilizes advanced reactors to ensure a supply of nuclear fuel well into the future. Development of the advanced reactors has been underway since the 60s but now it is really picking up again. In my Nuclear Engineering department at The University of Michigan, for one, there are a group of professors and graduate students devoting lots of time to designing fuel cycles and looking at safety concerns of sodium-cooled fast-reactors, one particular option for the advanced reactors.
The advanced concepts will not be ready to be deployed for at least 15 years at best. So keep up the good words for nuclear power and we'll have an environmentally safe energy source. For more information on what the nuclear community is looking into, check out the generation 4 roadmap at: http://gif.inel.gov/roadmap/
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Yes, of course hydro and wind will work at night as well as in the day. But there simply isn't enough wind or hydro power to run places like the US northeast. Where there's hydro, it should be used. I think Oregon is like 80% hydro right now. Awesome, but that only works in isolated areas. Solar, on the other hand, probably brings enough power even to the US northeast if you can capture enough of it. But then you have to worry about storing it. that's what I was talking about.
Really? Can we just up and power the USA through the night with wind, solar, and hydro? I think not. These sources are intermittent. We either need baseload 24/7 reliable power or an incredible amount of energy storage. How much storage you ask? If you assume 100% efficient pulleys, you'd have to lift 44 fully loaded Nimitz class aircraft carriers (100,000 MT) to the top of the Burj Dubai (818m) and slowly let them down, turning a turbine throughout the night (9hours) to replace a single large power plant (1GW) for 1 night. To power the whole country through a night, we'd have to lift and drop 22,000 of them daily. The scale of this problem cannot be tackled by the intermittent renewables alone by any stretch of the imagination. We need to augment solar, wind, and hydro with nuclear power and plug-in hybrids. Cool. For calculational details and a pic of 44 aircraft carriers on top of the Burj Dubai, see this page [whatisnuclear.com]
Surely a chemical explosion of 5kT would be detonated by multiple detonators. But to get that much power, you literally need a large room full of explosives. You can never reach the signature of nuclear devices with chemicals.
We had a departmental meeting about this the other day where a bunch of nuclear engineering professors got together and discussed what they thought had happened. The concensus was that this was actually a nuclear device. Almost definately. The seismic signals are the giveaway, and here's why. When a pile of chemicals explodes, they explode on a timescale of the speed of sound. So, the seismic signal from the explosion would be on the order of micro- to milli-seconds. When a nuclear device explodes, it happens in the time it takes for fast neutrons (>200keV) to get across a few centimeters. Now we're talking about nanoseconds. The seismic people have enough experience looking at explosions to be able to tell chemical from nuclear, and this one apparently looks nuclear. It also looks to be 0.5kT or so. That makes it by far the smallest yield 1st test ever. Which either means they have perfected making small bombs (which is incredibly complicated and wasn't done by the Los Alamos people until 15 years after their first test), or they failed in their test. The latter is very likely. They've also wasted a lot of Pu-239 or U-235 (probably Pu) and contaminated their expensive underground test facility. Lets count the days together to see how long they take to test again. If it's quick, they have plenty of material. Only time will tell.
While it is true that at the supply of cheap fissile Uranium-235 (the fuel for conventional nuclear reactors) could possibly run out within 50-100 years, options such as fast breeder reactors and thorium-based fuel cycles have the capability to continue fueling conventional reactors for hundreds of years. The advanced reactors can run on abundant resources while producing excess fissile material. They actually produce more fuel than they burn. They also can process spent fuel (nuclear waste), converting most of it into usable fuel and the rest of it to a form that will only be of concern for 500 years as opposed to 100s of thousands. The advanced reactors could produce enough electricity using only the accumulated nuclear waste in the USA to power the whole country for at least 200 years. That's something worth looking into.
Believe it or not, but George Bush has already proposed and funded the Global Nuclear Energy Partnership (GNEP), which utilizes advanced reactors to ensure a supply of nuclear fuel well into the future. Development of the advanced reactors has been underway since the 60s but now it is really picking up again. In my Nuclear Engineering department at The University of Michigan, for one, there are a group of professors and graduate students devoting lots of time to designing fuel cycles and looking at safety concerns of sodium-cooled fast-reactors, one particular option for the advanced reactors.
The advanced concepts will not be ready to be deployed for at least 15 years at best. So keep up the good words for nuclear power and we'll have an environmentally safe energy source. For more information on what the nuclear community is looking into, check out the generation 4 roadmap at: http://gif.inel.gov/roadmap/