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Comment After nuclear engines&reactors are developed.. (Score 1) 163

Attempting anything at scale in space with chemical rocketry is utterly foolish. Also, even if we put people on Mars, they need a dense, compact, and reliable source of power. Nothing but nuclear engines and reactors even remotely fit the demanding requirements for long-term space activites. A molten salt reactor can be made compact enough to power an airplane, and would be suitable for use in a Mars colony, providing electricity, heat, and production of chemical fuels. The endeavor was scrapped because ICBMs made it obsolete, but the only practical challenge was shielding, and that would not be an issue on mars.

In any case, we have a much greater need to develop the technology here on earth first; nuclear power is the only option capable of providing clean and reliable energy at the scale humanity requires. Until people can accept that, we will continue to waste massive resources on the fantasy of wind/solar, while our reliable power continues to be provided by fossil fuels, or worse yet, by burning trees or other "biofuels".

Comment Energy farming... (Score -1, Troll) 145

“It is ordinary human habitation and use (farming, forestry, hunting) of land which does most ecological damage.”

That includes energy farming as well, wether biofuels, biomass, or wind and solar. The latter aren't quite as bad as feeding crops and pelletized forests to the flames, but wind and solar are still extremely diffuse, and the collection hardware has a large ecological footprint. Not only the vast swaths of land permanently occupied, but the access roads and transmission lines. Moreover, wind and solar are both highly resource and energy intensive to manufacture, and that energy comes from coal. It is an extremely inefficient use of our resources for very small, if any benefit.

Energy density matters, as do modern farming techniques which allow more food to be produced on less land. We should be focusing on concentrating our activities in the smallest possible area, not "harmonizing" with nature by using expensive and ineffective technologies which were abandoned centuries ago. Ecomodernism shows us the way, while conventional "environmental" organizations demonstrate no regard for preserving ecosystems, and only a single-minded focus on anti-nuclear activism, which inevitably translates to burning more fossil fuels.

Comment Pixel C is A5 (Score 1) 208

The Pixel C is almost exactly the A5 ISO paper size. The display is 2560x1800 at 308ppi, and the speaker even mentions the sqrt(2) aspect ratio, so this isn't likely to be a coincidence. Another attractive device, following the 3:2 (2560x1700) Pixel. It is unfortunate that more manufacturers don't follow suit and insist on using TV resolutions.

Sadly, the usual complaints apply: no pen/digitizer, and pitiful storage options. Also disappointing is the still missing nexus7, which was a very nice device at reasonable price point. An A6 replacement for the 16:10 nexus7 would be welcome. The size would be only a bit larger, but with a better aspect ratio for print or web pages.

Comment Re:For future reference, (Score 2) 221

You keep arguing as if the Lapcat A2 uses a conventional engine, which it does not. An entirely new thermodynamic cycle takes advantage of the extremely cold fuel to significantly improve efficiency. Rather than armchair speculation based on generalizations, I'm more inclined to trust the actual modeling done for these engines and aircraft, for which the numbers look very promising. The engines are based on SABRE, and the ESA is confident that the design is sound.

Comment Re:Wind energy is such shit (Score 1) 327

That is a reasonable argument, but consider that a nuclear plant is closer to 8 acres per GW, and that is 1GW 95% of the time, not some pitiful fraction of renewable nameplate capacity. Together, these factors give nuclear a footprint many thousands of times less than renewables. Please, let us not pave the world to harvest the sparse energy of wind and the sun, when there are better alternatives.

Once one considers the resources that wind and solar require, including land, materials, and the fossil fuels to produce them, the only reasonable conclusion is that they are an environmental travesty. Beyond the thousands of tons of concrete, steel, and rare earths required for each unit, there are vast expanses of land which must be razed to make way for access roads and power transmission infrastructure out to the middle of nowhere. (Which will be poorly utilized because of the low capacity factor, and not economically viable.) One can appreciate how fruitless and ludicrous this exercise is with only a bit of math, or by objectively viewing the results of the "progress" to date. See The Renewables Future – A Summary of Findings.

Comment Re:The oceans have radically changed before ... (Score 4, Insightful) 417

For those who don't read the article:

“The level of CaCO3 saturation would decrease by 50 percent or more, and colder oceans would become corrosive to CaCO3 shells,” Taro said. Plus, the last time the oceans got this acidic this fast, 96 percent of marine life went extinct.

Once it gets acidic enough the plankton are done for, and they compromise the base of the food chain in the ocean. Yanking that out kills just about everything else, save a handful of species like jellyfish. The many humans who depend on the ocean for food will also be troubled to say the least. This really isn't an academic matter about what is normal or changing; this issue is both more urgent and far more serious than any expected effects of global warming.

The science is rock solid and very simple, and the historical record leaves no room for misinterpretation. What CO2 we put into the air, ends up in the ocean, and we can project the acidity like clockwork merely using the record of the carbon we dump into the air each year. By 2100 it will already be too late; we need to begin addressing this before 2050, and in earnest. It is difficult, but not impossible with a rapid expansion in nuclear power, but no other source can scale fast enough.

"Environmentalists" fighting tooth and nail to dismantle carbon-free nuclear generation, and insisting that we can decarbonize with renewables alone will doom the oceans if they have their way. If you are supporting anti-nuclear organizations like Friends of the Earth, Green Peace, or the Sierra Club, please think about just how foolish their priorities are before the challenges we face. Consider Ecomodernism for a perspective that values preserving the environment, rather than adhering to a rigid and ineffective ideology.

Acidification, Climate & Energy is a talk given by Dr. Alex Cannara at TEAC7, and it outlines the staggering extent of the problem, and how we can begin to address it. Dr. Cannara has also given a number of other talks on the subject, and searching for "ocean acidification" on youtube will keep one busy for hours. Incidentally, addressing ocean acidification will also resolve global warming, particulate pollution, energy poverty, and population growth as welcome side effects. It all begins with rational energy policy though, and discarding the notion that we can afford to rule out our most powerful carbon-free energy source.

Comment Re:8 years, and still stuck at 2-4 cores... (Score 1) 98

You missed the part about minimum; it is meaningless if Intel offers some hideously expensive outlier part. Granted, there are some six core variants which cost less, but they are still expensive 130-140W LGA2011 parts. The mainstream is still stuck squarely with 2-4 cores. Two cores in 2015 is pitiful.

Comment Re:Moor? (Score 1) 179

More importantly, it is byte addressable and doesn't require any of the block erase nonsense of NAND. There is no window during which some (possibly old) data or even the entire device becomes corrupted because of a power loss during a read-modify-(erase)-write cycle. It would be genuinely good if such reliability became a standard feature.

Comment Blame NAND Flash Memory... (Score 1) 184

While an apology is due, this sort of problem is inevitable given the nature of the technology. TRIM on NAND is a crutch for a technology that is poorly suited to data storage. Transforming NAND into a usable storage device requires heroic efforts on the part of the vendor, and it is hard to blame them for the bugs. Likewise, it is hard to blame Linux developers for their heroic efforts to work around the extensive deficiencies of NAND flash. Trusting in cheap commodity devices that don't even claim to protect against power loss is ill-advised.

Using TRIM as a band-aid for the performance woes of over-filled NAND devices is just asking for trouble. It has long been known that filling up filesystems leads to terrible performance, and the same applies to NAND drives. It is irresponsible of the vendors to provision the drives with insufficient reserved space, but one can compensate by setting aside an empty partition covering 5% of the space. It is much safer to disable TRIM and under-provision the drive, and it achieves the same effect of limiting write-amplification, without having to worry about bugs trimming away live data.

The only place were TRIM really makes sense is in the context of virtualization. Recovering space in sparse virtual disk images has real benefit, and operating system vendors have a lot more incentive and ability to make it work properly.

Comment Re:Everything has consequences (Score 3, Interesting) 105

2. is the renewable option, which is worse than doing nothing as it has large ecological and economic impact for virtually no benefit.
3. may be necessary at some point for things like ocean acidification, but doesn't solve the fundamental energy problem.

However, limiting oneself to three unworkable options isn't productive, so let's introduce another:

4. the nuclear option; ie. doing something which actually works. The BRIC countries are already embracing this one.

I prefer 4, as it provides reliable carbon neutral energy with minimal environmental footprint. Density is key, in energy as well as other human endeavors. I refer people to An Ecomodernist Manifesto for the motivations. Those who truly value the environment and prosperity of humans should read that. The end goal is well within reach, but indulging in the "green" fantasy won't lead us there.

Comment Re:Energy in perspective (Score 1) 116

...and it will be depleted if we continue to pump it out of the ground. We need a sustainable and carbon-neutral replacement, and synthetic carbon-neutral fuels can be created with nuclear heat. Today, ammonia is produced using natural gas as a feedstock, but it can also be created with nuclear heat. With abundant energy, most anything can be produced, and LNG is no exception.

Either way it would be better to look for alternatives, rather than heating our homes and producing fertilizer with something that is both running out and increasing in price. That is idiotic.

Comment Energy in perspective (Score 1) 116

This ship is a marvel, and showcases the truly impressive capabilities of modern shipbuilding industry. What isn’t mentioned, but is equally impressive, is the rate at which such shipyards can turn out new ships, and the surprisingly low cost. However, one can’t help but lament that this capability isn’t being used to produce ThorCon reactors, instead of draining resources for a quick profit. (Do have a look at the white paper, it provides fascinating perspective.)

This LNG ship extracts and condenses 3.6 million tonnes of natural gas per year, with an energy density of 55.5 MJ/kg, giving:

        3.6e6 tonnes/year * 1e3 kg/tonne * 55.5 MJ/kg = 199.8e9 MJ/year
        or 199.8e9 MJ/year * MWh/3600 MJ * TWh/1e6MWh = 55.5 TWh/year

This yearly energy content represents a continuous power output of:

        199.8e9 MJ/year * GJ/1e3 MJ * year/(365.2425*24*3600)s = 6.33 GW

That is the equivalent of a few large power plants. In the scheme of global energy requirements though, it barely registers: world energy consumption in 2008 was 143,851 TWh.

Now, given the energy density of Uranium/Thorium at 80e6 MJ/kg, the energy contained within that 3.6 million tonnes of LNG could instead be derived from:

        199.8e9 MJ/year * kg/80e6 MJ * tonne/1e3 kg = 2.5 tonnes (of U or Th)

That is a rather small number, but lets put it in terms of volume. With Uranium at 1.5e9 MJ/L, or Thorium at 9.3e8 MJ/L, that amounts to roughly the size of a yoga ball:

          U: 199.8e9 MJ * L/1.5e9 MJ = 133L (sphere of radius 32cm)
        Th: 199.8e9 MJ * L/9.3e8 MJ = 215L (sphere of radius 37cm)

The fun part happens when you scale it back up to the global energy consumption of 143,851 TWh, and it translates to a meager 6500 tonnes per year, capable of replacing the billions of tons of fossil fuels we consume today. Even with projected growth, global energy demands could still be satisfied by a single mine, to say nothing of the billions of tons of uranium available in seawater. Before that is necessary, the tens of thousands of tons of so-called “nuclear waste” can be consumed, as they still contain ~95% of the original energy content.

Comment Should have been 64-bit from the start... (Score 3, Interesting) 67

If only Apple had postponed the Intel transition for about 6 months, their machines and software could have been 64-bit across the line, and this mess would have been avoided completely. Instead, we are eight years into yet another transition, with plenty of legacy 32-bit software out there, any of which require an entire duplicate set of shared libraries to be loaded.

Comment Re:I thought rare earths were not that rare (Score 1) 62

They are producing ore, which is then shipped to their facilities in China for processing. Is that really progress?

Molycorp reopened the mine, and then bought Neo Material Technologies for its processing capabilities:

But the deal also paves the way for Molycorp to ship minerals from its California mine to the Chinese operations of a Neo Material arm called Magnequench, in a reminder of how much technological rare-earth capability resides in China.

To do two things at once is to do neither. -- Publilius Syrus