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Comment: Re:I'm quite surprised it wasn't (Score 1) 459

by Rei (#48425447) Attached to: What Would Have Happened If Philae Were Nuclear Powered?

And a lot better than Huygens, who they weren't even trying to keep alive at all and whose mission wasn't even designed suchly that Cassini could stay in touch with it until its batteries died.

The results of this mission have been invaluable in learning more about the challenges of landing on a low-gravity body. I look forward to whatever mission turns out to be the next followup that learns from all of the lessons of this mission. :) Maybe some sort of "hopper" probe that can sample all over an asteroid or comet by deliberately bouncing around?

Though to be honest, what I look forward to more than anything is the next dedicated Titan mission.. whether it's a hydrogen blimp, hot air balloon, helicopter, fixed-wing aircraft, tilt-wing aircraft, or whatnot, it's going to be bloody amazing. My favorite approach is that of a tilt-wing aircraft, which gains the high-speed / long range capability of an airplane, but can easily land and do surfacescience while its batteries are RTG-charged for the next flight. Even a sample return stage is a possibility, although difficult... an aerial vehicle can get extremely high in the atmosphere and the gravity's not very intense, so the escape stage requirements should be manageable, and then the escape capsule can use reverse gravitational slingshots and aerocapture to get samples back to earth with minimal additional delta-V. Can you imagine that - samples of the shoreline of an organic sea or cryovolcano from Titan, back on earth? Regardless of what sort of mission profile it has, though, the next Titan mission will have to be nuclear powered.

Comment: Re:I'm quite surprised it wasn't (Score 5, Informative) 459

by Rei (#48424593) Attached to: What Would Have Happened If Philae Were Nuclear Powered?

The entire system is designed to operate in peak loads much of the time with long idle periods between, you can't downsize the battery that much.

And RTGs are heavy compared to their output in the inner solar system. A SNAP-19 fits the generation bill (30 watts at beginning of life) but that's 12 kilograms, which is almost certainly heavier than the solar panels.

But the real reasion is, what others have mentioned, cost. And no, it's not a case of "the cost part itself is largely due to politics", it's that plutonium-238 is simply expensive, period. You're talking a product only produced in a few parts of the world from a raw material (neptunium-237) that's only extracted in a few parts of the world in very small quantities from a raw material (nuclear fuel rods) that's already very expensive and difficult to transport. The neptunium takes years to accumulate in its reactor and must be handled with extreme safety protocols during the extraction, and properly secured against misuse. It then must be irradiated for long periods of time, converting it one atomic collision at a time to plutonium 238 using a tremendous amount of energy. Only then can the plutonium be extracted - and once again, you're talking the need for extreme safety protocols during the process, and proper security. None of that is "politics", it's simply the way it is plus very rational handling procedures.

Comment: Re:mined and refined profitably (Score 1) 27

by Rei (#48422771) Attached to: CMI Director Alex King Talks About Rare Earth Supplies (Video)

I personally feel the solution to the "exporting pollution to other countries" problem is PAT - Pollution-Added Tax, implemented in exactly the same manner as VAT except for taxing the pollution emitted during that stage of manufacturing (based on a standardized set of rates) rather than value added at that stage. "Pollution" being everything from arsenic dumped into rivers to carbon dioxide dumped into the atmosphere. Just like VAT, goods produced outside the PAT zone would get PAT levied upon import, and goods inside the PAT zone would get rebate upon export - hence, there's no "I can make goods cheaper by producing them somewhere with little environmental controls" advantage. And because we know that VAT is legal and functional in today's global environment, we can be comfortable that PAT would be as well.

Comment: Re:Chinese cornering the market? (Score 2) 27

by Rei (#48422731) Attached to: CMI Director Alex King Talks About Rare Earth Supplies (Video)

That would be because the problem was by and large resolved.

Metal prices can fluctuate by several orders of magnitude in the short term. They can fluctuate to a moderate degree in the mid-term. But the long-term trend of metals as a whole is almost always downward (excepting "investment metals", which are inherently distorted by investors). There's no shortage of anything in the crust. The crust is unimaginably massive. It's always a question of what you've found, what extraction processes you've gotten mature enough to compete, and what infrastructure you've actually built. As a general rule, most resource "reserves" rise over time, not drop, because each tech advancement tends to put exponentially more resource into play.

Comment: Re:They WILL FIght Back (Score 1) 489

by Rei (#48417811) Attached to: Rooftop Solar Could Reach Price Parity In the US By 2016

Until you can "STORE" the power the fucking windmills and solar shit are just subsidy milking machines.

You mean by, say, drawing more from Ontario's 8.5 GW of hydro capacity during low-renewables times times and less during high times? Something along those lines?

(and not to mention, those plants were designed for relatively constant use... you can upgrade the powerhouses without having to rebuild the dams (aka, at a very low cost per MW) to be able to give significantly higher peak outputs if you ever decide you need them)

Comment: Re:They WILL FIght Back (Score 1) 489

by Rei (#48417721) Attached to: Rooftop Solar Could Reach Price Parity In the US By 2016

Think 24/7 heavy truck traffic, seemingly random road closures to move turbines/blades that were never communicated to the locals

Oh, you poor baby, you had to live near a construction zone! Nobody else on earth has ever had to deal with that hardship, clearly!

huge amounts of deforestation (nine thousand acres worth)

First off, this is a lie. The whole wind farm is 9000 acres, but the turbines and surface roads only take up a tiny fraction of that land. If you zoom out your linked map a couple clicks, you can't even make out a difference from the surrounding landscape.

But hey, let's just ignore reality and pretend that they marched in and bulldozed flat 9000 acres, ripped up all the ground and dumped it into the streams for 141 megawatts that will be maintained for, oh let's say 50 years with a 35% capacity factor. So about 2 GWh of electricty per acre of bulldozed land, which is less than that for mined coal. Except that coal fully bulldozes (nay, outright excavates to great depth) its land in reality, not fiction, and what they excavate either goes into overburden heaps, is purposefully dumped into streams, or is coal that is burned, creating massive amounts of fly ash and clinker to be retained (at great environmental cost) and massive amounts of emitted pollution into the air (at even greater environmental cost).

In reality, that wind farm and its access roads is taking up, what, perhaps 4% of that area? So something like 50 GWh of electricity per acre.

But oh hey, it's not in your backyard, so you couldn't care less! And hey, it has a few slowly blinking red lights at night, clearly that's so much more of an eyesore than a damn coal mine!

Let's contrast that to nuclear power, the cutting edge of 1950s technology: Nine Mile Point [wikipedia.org] occupies 10% of that footprint (900 acres), hosts a second power station [wikipedia.org] on the property and between the two can generate 2,599 megawatts 24/7/365 regardless of the weather.

First off, false. Nuclear power plants have higher capacity factors but they do not have 100% capacity factor.

Secondly, you forgot to account for mining. Uranium mining has a significantly smaller footprint than coal mining per unit generation, but it's still a significant area due to the fact that they're mining for a fuel found in ppm quantities - and of the uranium they mine, U235 is only 0,7%, even of that they don't get all of it, and of that that goes into the fuel rods, only part of it gets consumed. Wind still wins on a real-world footprint comparison.

Third, uranium mines, being mines targetted at heavy metal extraction, generally have a far more profound impact on their local environments than coal mines on an acre-per-acre basis (coal mines only win on destruction due to their sheer size).

Fourth, you didn't account for reprocessing / long term storage.

Fifth, you didn't account for the consequences on rivers for dumping nearly two gigawatts of waste heat into them.

Sixth, most studies pin nuclear at significantly more expensive than wind per kWh. And wind prices are falling while nuclear has been rising.

Lastly, most people's opposition to nuclear has nothing to do with any of the above, so you're not even started getting into the reason why many people don't like it.

"The hottest places in Hell are reserved for those who, in times of moral crisis, preserved their neutrality." -- Dante

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