Fusion Reactor Concept Could Be Cheaper Than Coal
It is indeed about accessing the energy already stored, which is what Q > 1 means. The Second Law of Thermodynamics will come into play when they convert that energy into useful work and electricity.
And the power conversion system is almost never talked about when fusion reactor designs are presented. Their journal article actually does mention a power cycle, which is nice to see. And they nonchalantly decided upon a supercritical CO2 Brayton Cycle to "maximize the overall efficiency". Reading through the small section on this, I don't think they've fully considered the extra engineering involved in dealing with that fluid (which can be quite corrosive for a number of materials) and the required experience to actually maintain that system. The choice seems to be one of what hip-and-new versus solid, robust technology (I don't know why people are afraid of water-based Rankine cycles; they're so nice). Their neutronics check out, but their power cycle analysis is lacking.
NRC Expects Applications To Operate Reactors Beyond 60 Years
The NRC's job is safety. That's it. They have people stationed at power plants, and their only job is to ask questions and enforce policies such that the plant operates safely. With that beaten home, let's get to some specifics.
The biggest concern for the current fleet of U.S. reactors (mostly all Generation II designs) in terms of long operation is embrittlement of the reactor pressure vessel (RPV) due to radiation damage (mostly neutronic). Embrittlement of the RPV comes into play when severe accident responses (for either Design Basis Accidents (DBAs) or Beyond Design Basis Accidents (BDBAs)) dictate fast, extreme cooling of the RPV that can lead to pressurized thermal shock (PTS) events. The biggest hurdle toward getting approval is proving which-and-every way to a high confidence level that a PTS breach of the RPV will not occur from this embrittlement. If plants cannot do this, the NRC will not issue a license extension because the plant cannot prove its safety. If you care to read more on it, consult 10 CFR 50.61 for details (or the whole thing at the10 CFR 50 Part Index.
Are there other requirements? Yes (see the 10 CFR 50 index above). However, this is the one aspect I wanted to expound upon since turbomachinery has been replaced/upgrade, fuel is refreshed every 18 months or so, and piping is constantly checked. But I wanted to stress the safety issue. The NRC has 100% no qualms about telling a plant "no" if that plant cannot prove it is safe to operate.
New Review Slams Fusion Project's Management
Actually, ITER is supposed to be a proof-of-concept. That is, ITER is designed to show that a controlled and burning plasma can be created and sustained over a long period of time with a net power out (like any baseload power plant should). It's a toroidal tokamak simply because it is one of the most well-understood fusion reactor designs; spherical tokamaks, inertial confinement, electrostatic confinement, and (my personal favorite) stellarators being less so.
DEMO, another experiment, is the next step and is intended to be the bridge between ITER and a commercial design. What is DEMO is still up in the air, but it will definitely be influenced by lessons learned from ITER and other various research institutions (like, shameless alma mater plug, UW-Madison with its toroidal tokamak, spherical tokamak, and stellarators experiments).
Kazakh Professor Claims Solution of Another Millennium Prize Problem
The post states that the paper "is claiming to have found the solution to another Millennium Prize Problems" while the article's title is “Existence of a strong solution of the Navier-Stokes equations". By my interpretation, the paper is claiming to show the existence of strong solutions (that is, solutions satisfying the Navier-Stokes equations in non-Weak Form subjected to some set of boundary data) not a general (or any) solution, in particular. While the proof of existence is the Millennium Prize if the proof includes smoothness (continuity after some degree of differentiation), the fact of whether or not these solutions exist is irrelevant to most (if any) Fluid Mechanics texts and engineers/modelers.
The post also states that the Navier-Stokes is "fundamental [set of] partial differentials equations that describe the flow of incompressible fluids"; this is true if all the physical parameters (density, viscosity, and pressure) are taken as constants such that an equation-of-state and energy equation are not needed. However, if they are not assumed constant, the Navier-Stokes equations also perfectly describe the flow of compressible fluids if equipped with an energy equation, an equation-of-state, and other constitutive relations as needed. The only rub comes in when dealing with a fluid that is either not a contiguous field (such as fluids that break-up when immersed in another or, in some cases, a fluid undergoing phase change) or a fluid that does not obey the Stokes Hypothesis (an extension of the idea of a Newtonian fluid to multiple dimensions) which is used as a constitutive relation for the stress tensor in the Navier-Stokes equations.
20 Years of MS Word and Why It Should Die a Swift Death
I was thinking the opposite. Since a Word Documents (.doc or .docx) require, by definition, Word to view on a computer, I would assume more people would publish/save to/print to PDFs since the format is highly portable with many free readers.
That is if the intent of the document is to be viewed. If it is to be edited amongst a group, feel free to choose in the group the editor/creator of choice. Word, Abiword, Lotus Symphony, OO Writer, LaTeX, Google Docs (where I mainly created in HTML and CSS when I do) ... There are a ton of document creators out there; no reason to hate on just one because everyone uses it (or just doesn't know about others).
First New Nuclear Reactor In a Decade On Track
The used assemblies, usually on a 12-18 month cycle, will be put into wet storage (a big pool of cooled water) for a period of time until all highly radioactive/short half-life substances have decayed to reasonable levels. Then they will be put into dry casks and stored on-site until such a time as the Federal Government opens a suitable long-term or interim storage repository.
What is the cost of waste disposal?
Nuclear waste disposal and technology development is all on the Federal Government. As per the Nuclear Energy Act of 1982, the generators (plants) will pay the DOE 1 mill/KWe-h (1 $/MWe-h) to assume ownership of the waste.
Have they factored that cost into their calculations?
Under the assumption that TVA is a money-making entity and has a finance department, I would assume they do
Wind Could Provide 100% of World Energy Needs
Not only that but if not for massive government subsidies nuclear power would not be profitable, it may actually loose money.
That is a funny thing to say considering that in 2007 the U.S. gave 4,875 million dollars to renewables (81% in Tax credits) opposed to 1,267 million dollars to nuclear (72% R&D) and 5,451 million dollars to Coal/Petroleum/Natural Gas.
Energy Information Administration Report
Wind Could Provide 100% of World Energy Needs
No need for a correction. The heat/kinetic energy from both fission and fusion reactions comes from the mass difference of the product(s) and reactant(s). The difference lies in that fusion combines light nuclei resulting in a surplus of energy per nucleon while fission divides heavy nuclei resulting in a surplus of energy per nucleon.
Wind Could Provide 100% of World Energy Needs
No need for a correction.
The heat from nuclear fission and fusion chain reactions comes from the mass difference between the products and reactants of the reaction. The difference lies in that fusion combines nuclei to achieve a higher energy per nucleon while fission divides nuclei to achieve a higher energy per nucleon.
Microsoft Launches New "Get the Facts" Campaign
Personally, I think anyone or any corporation using IE6 or below should not be allowed to use the internet. And frankly, if Microsoft needs to lie to the loads upon loads of people who couldn't care less about their computer or how applications kind of work or what a browser is or anything at all and just want it to work WITH NO EFFORT (because god forbid they might have to think one iota past the "Install" button) to get them to upgrade to a piece of software that is not entirely garbage, so be it. It is America after all. And Apple ads do the same thing some times.
Univ. of Wisconsin's 30-Year-Old Payroll System Needs a $40 Million Fix
Same sentiment here. A single university (UW-Madison) can barely upgrade correctly. And when they do it sucks.
Adminstration has no clue what computer systems are and which ones are good for a single University let alone a state-wide system. Good forbid someone walk over to the local CS department (if they even know what that stands for) and ask for advice, or ask if there are a few dozen Grad Students looking for tons of funding (longshot there, but oh well).
Should Undergraduates Be Taught Fortran?
I am in a similar boat in my engineering department and have the same work flow. Matlab for small/simple problems (although, as computers become more powerful, "small" becomes larger), and Fortran for large/complex problems. And it works well. ( Large = someone in a separate group makes 2 GB binary information dumps with an FEA plasma code).
I do know C and some portions of C++ (purely from my free time), and I must say that a majority of the threads above ignore the idea that Fortran is destined for computations. As such, having the worry about pointer assignments (mainly keeping * and & separated) or being required to make prototypes or load individuals libraries is just not needed for NUMERICAL computing.
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