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Comment Of course, when biomass is considered "renewable" (Score 0) 169

When renewable advocates boast about energy production, the numbers are inevitable inflated by huge amounts of biomass, or meaningless capacity numbers which do not represent actual energy delivered. Leveling forests to burn for fuel is not environmentally friendly, and not even carbon neutral on the time scales that matter. In some cases, forests are pelletized and shipped over seas, making the carbon impact even worse than burning coal. Unfortunately, aside from hydro, it is the only renewable that is reliable, and thus forms an integral part of "renewable" plans. More typically though, coal and gas take up the slack.

Read more about Australia specifically, or bioenergy in general. Sadly there is only one form of clean energy that is environmentally friendly and scalable, and the renewable fanatics will have nothing to do with it, instead promoting a world of poverty and mass environmental devastation. While solar and wind have their place, it would be much more effective to complement them with nuclear instead.

Comment Re:Expert?? (Score 1) 442

Not at all. It just requires enough smart equipment to cope with whatever the variation in supply is. Even on an entirely renewable grid there will still be a lot of base load available, from non-intermittent sources like hydro and from the minimum output of variable sources like wind. If you have enough turbines the wind is always blowing somewhere, and the overall output of the entire fleet never drops below some predictable level.

There is a lot of industrial equipment and processes that requires a constant source of power. Moreover, even if some can cope with the variability, the economics often fail when capital intensive facilities are sitting idle 2/3rds of the time. The wind is also calm for weeks at a time over large regions, requiring either 100% backup or storage; the idea that we can satisfy our needs by shuffling renewable energy around that isn't available through a grid that doesn't exist is pure fantasy.

Also note that he isn't say "no storage", just no grid level storage. House pack batteries and EVs, even small local pumped storage will be available.

I'm not saying this is a desirable state of affairs, merely possible. In practice it would make a lot of sense to have grid level storage.

How many people are likely to use their hideously expensive vehicle battery in this way when it severely shortens its life? It also suffers the same problem as "smart equipment"; we can't afford to toss out and replace every last piece of technology.

The only realistic way of curbing our CO2 and other pollution is to produce carbon neutral fuels for existing engines, and clean energy for our existing grid. Only nuclear is capable of providing the reliable and affordable energy necessary to cleanly power modern civilization. Otherwise we will be lucky to keep the lights on at night while the remainder of our industry departs for China. More likely though, we will continue leveling mountains for coal as the true believers refuse to let go of their fantasy.

Comment Re:The question should be, what is causing delays? (Score 1) 142

Do you have a citation for this "environmental damage"? Real damage, not caused by nuclear weapons manufacturing, and not the "OMG, three atoms of tritium escaped, we're all going to die!" sort of "damage".

The costs of the plants are a matter of record, so have a look. The NRC opened the door for litigation, and otherwise mired the nuclear industry. The AEC was an effective regulatory agency with an excellent safety record and reasonable costs. Under the NRC, costs skyrocketed and a number of reactors were even partially built yet never operated. Abundant examples are no further than your nearest search engine.

Comment Re:The question should be, what is causing delays? (Score 1) 142

True, but the idea behind the combined operation license was to allow construction and operation to continue while license issues are litigated. The delays in plant Vogtle and in SC are from the challenges with actually building the plant since much of the equipment has never been built before so they must building, testing, and constructing while they are trying to create a commercial plant on a tight schedule.

While there are very real concerns about the lack of construction experience as well as longer term engineering and operational support, these delays seem to be self inflicted, from issues with concrete pours to assuming brand new designs can be built on a very tight schedule where many of the components have never been built or used before.

Read more about the the Vogtle rebar issue. It is not fair to dismiss it as self-inflicted, when the regulator insists upon perfection and is unresponsive to circumstances. The rebar was installed to current building standards, rather than those in place when the design was approved. It was a small deviation and eventually the NRC allowed it with minor modifications. The problem is that such a minor issue can introduce a 6+ month delay when interaction with the NRC are required.

Regulations should be focused on safe designs, not on libraries of paperwork certifying safety. It is silly to require an N-stamp on every last nut and bolt (even in non-safety related systems) rather than using off the shelf parts where suitable. Certificates can be forged, and even if they are genuine, nothing is perfect. Safe designs make allowances for imperfect materials. Such a “cost is no object” approach is not useful in the real world, The oppressive regulatory regime only mires any progress and ensure that we are burdened with ancient, yet "approved" designs.

Comment The question should be, what is causing delays? (Score 2, Insightful) 142

Typically the endless lawsuits and anti-nuclear activism are the source of delays for nuclear construction. Even if not directly, then by proxy of the NRC, which is ineffective thanks to regulations based on ALARA and pseudo-science (LNT). If the NRC regulated based on solid science and legitimate safely concerns, it would be tremendously less expensive to meet nuclear safety standards. Unfortunately, our presidents have had a habit of appointing unqualified and nuclear-hostile people like Gregory Jackzo to lead the NRC, so the result is no surprise.

Another source of delay, is the lack of nuclear construction for decades, leaving the construction industry and supply chains to languish. Neither cost is inherent in nuclear construction, and both can be corrected. Delays of any large construction project are very expensive, and this is the primary means employed by anti-nuclear ideologues to drive up the cost. The submitter (mdsolar) may or may not have participated, but clearly has an axe to grind and the willingness to exploit the situation to peddle his ideology

Comment Re:Static scheduling always performs poorly (Score 1) 125

One might expect that, but the Mill is exceptionally flexible when it comes flow control. It can speculate through branches and have loads in flight through function calls. The speculation capabilities are far more powerful, and there are a lot of functional units to throw at it. There will be corner cases where an OOO might do slightly better, but in general the scales should be tipped in the other direction. If anything, the instruction window on conventional hardware is more limiting.

Papers would be great, but peer-reviewed venues also tend to reject things which are truly novel. The group has written papers only to have them rejected for absurd reasons, one being a lack of novelty and hard numbers or something like that. They are clearly not interested in writing papers or even filing patents, and we are fortunate (or not) that their hand was forced on the patents with changes in law.

Comment Re:Static scheduling always performs poorly (Score 1) 125

I think your generalization of static scheduling performs poorly on a Mill. :) The Mill architecture uses techniques which essentially eliminate stalls even with static scheduling, at least to about the same extent that an OOO can. Obviously, there will be cases where it will stall on main memory, but those are unavoidable on either. See the Memory talk in particular for how the Mill achieves this, and other improvements possible over OOO. The entire series of videos is fascinating if you have time, but there is also a short introduction. Beyond that, there is a considerable amount of detail scattered in the forums which the videos don't cover.

The Mill aims to provide OOO performance with DSP level efficiency, and offers a defensible means of doing so. Ultimately, any complex schemes aimed at keeping functional units busy are a waste of power if that result can be achieved with simple static hardware.

Comment Re:Sounds smart, but is it? (Score 1) 125

There is a lot of information available on the Mill architecture at this point, and very little reason to doubt its feasibility. Essentially all of the parts have been demonstrated in existing architectures, and the genius is in how they are combined in such a simple and elegant manner. Implementation issues aside, the idea is rock solid, and has too much potential to ignore. Perhaps the layman can not appreciate it, but the architecture has a profound ability to simplify and secure the entire stack of software on top of it. Even without silicon, that much is clear, and no doubt why there is so much excitement.

People look at architectures like a black box and fail to appreciate that the quality of applications they use are heavily dependent on what systems and language programmers can provide using that box. Not many have experience with such low level code, but it is a nightmare to produce and maintain on conventional architectures. It is fragile and full of cruft, requiring tremendous effort to optimize compilers/languages/libraries/etc. The Mill wipes away the need for such effort and enables trivial yet superior compilers, systems, software optimization and security. Those costs are worth arbitraging, even if the Mill itself offered no performance advantage. However, a Mill is actually very similar to a DSP from the hardware perspective so it is easy to extrapolate.

(Incidentally, the Mill is also expected to be an excellent platform for micro-kernels. The value of micro-kernels has never been in question, but there is a significant performance trade off on conventional architectures. L4 has done well in minimizing it, but on the Mill there will be no contest.)

Comment CPUs should be replaced upon request, or... (Score 1) 131

Alternatively, Intel should stop artificially segmenting their product line on every last instruction set extension or feature. ECC and VT-D should be standard features, yet are intentionally crippled on other Intel chips. If I paid extra for a Xeon, then I expect those to work and TSX is no different.

It is infuriating that developers and users alike must face such a mishmash of arbitrarily enabled functionality just so Intel can extract further profit, even while bragging about their low defect rate on the 22nm process. I'm not saying that processors shouldn't be binned, only that it should be done on the basis of defects. It is criminal to arbitrarily destroy value in the pursuit of profit, and maybe the law should reflect that.

Comment Re:Solution! (Score 1) 151

The problem, is that there aren't enough of them. ;) More seriously, that is basically what geothermal does, and it is useful where available. Exploration and drilling are expensive though, and suitable sites are limited. Interestingly, while the environmental effects are minimal compared to fossil fuels, they are still not as benign as with nuclear. Drilling releases greenhouse gasses trapped deep in the earth, among other things including radon. (Hence both geothermal and fracking put out more radioactivity than nuclear plants, though still nothing to panic over.) Fundamentally though, geothermal is merely indirect nuclear, taking advantage of the decay of thorium and uranium within the earth itself.

Comment Re:Solution! (Score 1) 151

That coal should be left in the ground, and not foolishly burned for energy. It is criminal to turn such a valuable concentrated carbon resource into ash, particulate, and CO2 and disperse it into our environment. Incidentally, there is more than 10 times the energy recoverable from the traces of uranium and thorium within the coal, than from combusting the coal itself. Of course, that isn't available if we mix the ash into sidewalks and roads, and such. (and it still contains some of the other nasties which didn't make it into our air or water already.)

The point is that there will never be "enough" coal if we continue using it as an energy source. It might last for a while, but conservation is still not sustainable. Conservation will only drive up prices for energy and preclude using it for energy intensive processes like recycling. Even producing the steel, concrete, and rare earths necessary for renewables is highly energy intensive and entirely dependent upon heat from fossil fuels today. Those renewables are also exposed to the elements and need to be recycled every decade or two. We are already reverting to burning trees, and it is only going to get worse until more people accept that nuclear power.

Anyway the crucial point is that nuclear provides reliable energy 24/7 through severe weather or natural disasters and with a minimal environmental footprint. They are among the most robust structures in existence, and molten salt reactors would be even more resistant to damage. (Granted, the transmission infrastructure is still vulnerable, and that is another reason why it should be minimized.) Even coal and natural gas plants can be taken off line by severe weather. During the recent polar vortex, it was nuclear which kept the lights on in New England.

Comment Re:Solution! (Score 5, Informative) 151

With an abundance of sustainable and reliable energy, survivability of an event such as a volcanic winter would be drastically increased. Energy is the only limiting factor in producing a 100% self-sufficient and self-contained living environment, not only in space, but on earth as well. Energy availability would be instrumental in facing such a disaster, and with adequate preparation we could manage quite comfortably.

However, if the green dream of a world powered exclusively by renewables were realized, humanity would have no hope whatsoever. The lights would go out indefinitely, and any sort of civilization would promptly collapse, with only a handful surviving in miserable conditions. Renewables are not reliable, and are incapable of sustaining civilization through such a crisis.

While efficiency is a laudable goal (to which most engineers already aspire), eking by with extreme conservation is highly anti-productive, and exacerbates environmental and societal problems. Energy is not a disease to be eradicated, but a resource essential for enabling greater levels of recycling and reuse, and ultimately a sustainable high quality of life with minimal environmental footprint. With prosperity, population also tends to level off, solving that problem as well.

Energy is only a problem when it is derived in an environmentally destructive manner, as with mining and extraction of fossil resources, or the vast and inefficient collection, storage, and distribution infrastructure for wind and solar. These sources also require extensive mining for the raw materials comprising the infrastructure, and the fuels required for transportation in both cases.

Owing to a far superior energy density, nuclear energy necessitates very little mining and supporting infrastructure. Molten salt reactors like LFTR use nuclear fuel roughly 200 times more efficiently than todays LWRs, and with passive safety and no need for water cooling, they can be sited virtually anywhere. For perspective, a 1GWe LFTR plant would be roughly the size of a Walmart. Incidentally, there are upward of 10,000 Walmarts, which would accommodate 10TW of LFTR power production--enough to provide for 10 billion people at US per capita power consumption.

Each year, a 1GWe reactor would only consume about a ton of thorium, and produce about a ton of fission products. All of the fuel required to power the world for a year could be mined at a site not much larger than a Walmart itself. However, it could instead be recovered from the tailings of rare earth or other mining already in progress. (For reference, a metric ton of thorium fits in a sphere 55cm (or 1.8ft) in diameter.) A plant could easily have decades worth of thorium on hand.

Of course, the picture wouldn't be complete without considering the waste. A single GWe of generating capacity is enough to power a sizable city, producing 1t (metric ton) of fission products per year. One might worry that these are going to accumulate and produce an intractable problem, but in reality the radioactivity is constantly disappearing, and will reach a steady state when the creation balances the decay. As 83% of the fission products of a LFTR are stable after a decade, and the rest no more radioactive than ore in 300 years, the sum total of waste produced for one GWe of power, will gradually build up to, yet never exceed 59t after 300 years. This is a trivial amount, which is still overstated as many of the fission products have uses. (radioisotope thermal generators, sources for medicine or food irradiation, etc.) Even if politics prevents doing something useful with it, it could still be safely stored in a small room on site.

Comment Reactor grade plutonium is useless for bombs... (Score 1) 104

Reactor grade plutonium is useless for bombs, and parroting the lie doesn't change that. See Dr. Helen Caldicott: Toilet Paper & Plutonium at 5:50. (The other Caldicott videos by Thorium Remix also offer further insight into a prototypical leader of the anti-nuclear movement. The source of this story, "The Bulletin of the Atomic Scientists" belongs in the same class and deserves similar scorn for their rampant intellectual dishonesty.)

However, the article refers to unexposed MOX fuel, which is not the same thing, and the isotopically pure plutonium-239 can be separated in that case. The problem is that when Japan halted all of their reactors, the MOX fuel never made it into a reactor; had it been exposed in a reactor, there would be no issue. The safest place for fissile is in the core of a reactor, where it is rendered useless for weapons while producing vast amounts of energy. Molten salt reactors do an even better job and can thoroughly destroy all of the remaining spent fuel as well, which releases roughly 20 times more energy yet.

Comment Re:Wait until those lamers find out... (Score 1) 385

Hanford was a weapons production site, which has nothing to do with nuclear power. Arguments against nuclear power on the basis of waste all fall flat, because the actual byproducts are short-lived and the quantity is a total non-issue. Hence, dishonest ideologues resort to conflating it with weapons waste, or using vastly inflated numbers which do not account for reprocessing. Even those numbers amount to nothing next to alternatives though, including highly resource inefficient wind and solar.

Once a modern reactor converts the remaining 99% of energy contained within spent fuel and depleted uranium into energy, there is virtually no waste at all. About 83% of fission products would be stable within 10 years, and the remainder in a few centuries. However, nearly all of it have uses and value if separated. Nuclear "waste" is a fictional problem created by people who insist on wasting valuable nuclear material, rather than putting it to good use.

Comment Re:Another misconception bites the dust (Score 1) 365

Some of it may be scrubbed, but there are still significant losses. Even a small fraction of a percent escaping results in substantial pollution when burning billions of tons of coal a year. Have a look at the contents, and that isn't even considering the contribution of CO2 to ocean acidification.

Germany should reverse course, as they are not on a path which will eliminate or even mitigate coal pollution. Current policy is driving prices up and creating a permanent dependence on fossil fuels to compensate for unreliable energy from wind and solar. A $100B spent on nuclear instead would have been a much wiser investment.

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