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In 1890's there was a panic over the imminent depletion of the worlds oil supply but then people looked at other places than just Pennsylvania. The talk about a "shortage" of Uranium is just a red herring, there is and will be plenty of fissionable material to last at least several hundred years at minimum. When we consider solar power we must also consider its liabilities, ie.the environmental damage due to building large solar collector arrays and wind farms in fragile ecosystems, and the un-reliability of supply due to weather. Similar issues plague the whole bio-fuels idea. As for accidents and radiation, there are more people killed injured and irradiated with radioactive waste from coal plants than if we had 20x the number of nuclear reactors and had a Chernobyl sized disaster every single year. It's not so much that nuclear is a good choice but that all the others are worse. Like Churchill said about democracy, nuclear energy is the worst system their is, except for all the others.
Breeder reactors are devices specifically used for creating more fuel than it consumes. The problem here is that we're only on a U-Pu cycle. There is another method: Th-U cycle. Thorium is several times more abundant than U and the U-233 produced has better characteristics for non-proliferation.
It has been done in the past and it is a proven technology on a grand scale. It is fear that prevents us from moving forward. Note that there is a direct correlation between people against nuclear energy and the amount of direct knowledge of the process.
I have been in nuclear energy for 10 years now. I was a submarine reactor operator and then left to complete a BS in Chemistry at Penn State. While there, I continued to work as a US NRC-licensed senior reactor operator. Now I'm working on the additional challenges associated with nuclear energy expansion, including waste management and fuel cycle supply. One would think that I have seen enough problems and agree with the anti-nukes and realize that it isn't practical. In reality, I have seen so much promise and potential in nuclear technology and energy production that brings me to the opposite conclusion.
Nuclear energy is with out doubt, a safe, clean and reliable source of energy. Spent-nuclear fuel is actually some 40 % unused fuel when it is 'spent' from an 18-month cycle in a power reactor. We need to recover this fuel and reprocess it to use it as energy. Further, an expansion of the energy-efficiency is to re-discover breeding technology to reduce the volume and radiotoxicity of the waster and generate more fuel as a by-product of heat energy.
People that are afraid or cynical of this technology simply are mistaken about its impact and capabilities and are only focused on negative perceptions, promulgated by public schools and movies. The real truth isn't that nuclear power is perfect (far from it), but the truth isn't that 100 % solar is the answer either. No one technology is the magic bullet. Nuclear power can provide the carbon-free energy for 40 to 60 years at 1 GW output reliably. Solar can't do that for that long of time. Wind can't do that either. Not to mention the fact that ANY solution has an environmental impact: none are perfect.
What we should move toward is a culture that handles its waste: all of it. Greening nuclear is an ever-evolving process. The French have been recycling spent-fuel for years and are always improving the process. That's how we proceed thoughtfully, practically and rationally. Nuclear power is NOT the only realistic way to reduce CO2 emissions, but it is a substantial part of the reduction portfolio.
Wm Michel I have to congratulate you on your presentation, sweet simple and to the point,
While I'm not an expert in any scientific field, I wholeheartedly agree with your conclusions, there is no silver bullet every solution has an equal number of advantages and disadvantages, and it;s only by combining them that we eventually find solutions.
do you think that eventually it may be possible to miniaturize this technology so that it could be used in isolated areas or locations
radiocopper points out very valuable information to the readers of this forum and one very important conclusion: NUCLEAR POWER IS ONE OF THE SEVERAL STRATEGIES TO REMOVE A "WEDGE" OF GHG GROWTH WITH TIME.
Let me now augment this strategy. We have in our country a new facility called the Spallation Neutron Source (SNS) which is operating at Oak Ridge. This device uses a linear accelerator (linac) to send protons into a heavy metal target and spit out FAST neutrons from the other side.
Such a billion-dollar tool is key to removing nuclear waste as well as making nuclear power safer. Several scientists, among them Richard Sheffield at Los Alamos, have explored "linear accelerator driven nuclear reactors" (LADR - google it) or "accelerator driven sub-critical reactors" (ADS) as a means to burn spent nuclear fuel rods and bridge between our present reactor technology based on critical masses and slow neutrons to a future technology based on sub-critical masses and fast neutrons.
Here are the advantages:
--- a sub-critical mass, such as a U238 fuel rod with its U235 depleted, or a thorium rod. Note that the nuclear reaction stops if you shut off / lose the outside neutron source, whereas for a critical mass it accelerates if you shut off / lose control.
--- proliferation resistance, since thorium is many neutrons away from plutonium and "burning" of the actinides in general will yield low mass nuclei
--- waste timelines of 300 years instead of 10,000 - the burnt fuel rods would consist of a minority portion (few percent) long-lived isotopes that could be chemically separated (although a significant challenge) and a majority portion of isotopes that decay relatively quickly. The 300 year mark corresponds to class C level of waste, akin to natural ore.
--- if present linac technology is used, a LADR or ADS can be used to make electricity on the scale of a 1 GW power plant. A lead-bismuth eutectic blanket is required - this is also existing technology. 90% of power goes to the grid, 10% back into the linac. There are challenges, but it should be workable.
--- Thorium is much more plentiful in the earth's crust than uranium
--- transients: While redundant linacs might get by an issue of reliability, no nuclear operator would ever want rapid power swings going into his atomic pile. Linacs do not surge though, but the ramp up would have to be studied.
--- cost: An up front invenstment of a few billion is needed; probably there would be one such national facility to burn the 250,000 kg (right?) or so of waste while fast neutron technology came online
The bottom line, however, is that new technology and new thinking enables nuclear power to be a viable source of energy as well as an important strategy to remove a wedge out of the fossil-fuel driven CO2 emittance.
Why would you want to continue using fission to produce power?
Let's get to fusion and solar, wind, sea, etc.
I need help ASAP on a chemistry question. Here it is.
Before 1982 U.S pennies were made of solid copper. As the price of copper rose, the U.S mint switched to a composition that is 97.5% zinc and 2.5% copper. A penny minted after1982 is 19mm in diameter and 1.6mm thick.
What is the volume of a penny in mL?
This is a very easy mathematics question.
Do it by yourself, lazybone.
Dude, use the bathtub method. (That is what our teacher calls it, when you mesure how much water is in a graduated cylinder and then put penny in and remesure then subtract) or find out weight in mG and convert.It's simple. Were you kidding? I'm 12 and I know that.
P.S. It may not be the scientific way, so if you have anything to say, keep it nice.
It's not an experiment.
It's a question.
Like a question for you to do math and find the answer using the calculator.
1) Ignore everything in the question but the dimensions of the cylinder.
2) Conversions 1cm^3 = 1ml, 1000mm^3 = 1cm^3, diam(d) = 2 x radius(r), pi = 3.14....
3) Formula for volume of a cylinder = 2 x pi x r^2
WebElements: the periodic table on the WWW [http://www.webelements.com/]