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  1. Re:Closed Loop on US Navy Tries To Turn Seawater Into Jet Fuel · · Score: 1

    Yeah, over geological time scales. CO2 dissolves into the ocean at a much higher rate.

  2. Re:Makes sense on US Navy Tries To Turn Seawater Into Jet Fuel · · Score: 1

    1: this won;t fit in any existing ships, we're talking new carriers... Retrofitting is basically impossible for a facility like this. Even if they used a scaled down system, not a full 250MW RFTS chamber, it would still be rediculously expensive to build one onboard, hundreds of millions, vs building one on land (tens of millions).

    Yep, probably new/majorly reorganized ships would be needed. But hundreds of millions probably isn't that much when you consider that a Nimitz class carrier already costs billions. You also have to consider that if your carrier group can supply it's own fuel, you no longer need resupply tankers with their associated escorts. This would probably save hundreds of millions in operating costs.

    2: the nuclear reactor is designed for a specific power output needed by the ship. Adding 50-100MW of additional load would be crazy.

    Additional load isn't needed because carriers rarely actually use 100% of their generation capacity. Besides, it isn't necessary to generate fuel constantly. It can be done when other electrical usage is low.

    3: only 20% of the output of RFTS is jet fuel, the majority is methanol and ethanol, and they'd have to store that until they get back to land, meaniung 3-4 times the tank storage of just filling up with jet fuel on land.

    The process can be adjusted to produce whatever fuel you like. It isn't a set ratio, and you could produce 100% jet fuel if you wanted to.

    4: the seawater to CO2 chamber would be massive, so would the elcrolysis chamber, not to mention MASSIVE seawater filtering systems. The inlets and outputs would also cause major issues with ship structure vulnerabilties.

    I'm sure that you can scale the process to whatever size is acceptable, structurally speaking, at a reduction in production capacity. Besides, all ships that carry variable loads already have ballast tanks... which have "inlets and outputs". I'm sure military vessels are no exception. You could probably even dual-purpose some of the ballast tanks as CO2 extraction or electrolysis tanks.

    5: the smaller ytou make the RFTS plan, the more expensive the fuel is. A 250-500MW facility on land (costing a fraction of an onboard equivalent) would produce fuel at less than half the price of a 50MW facilty, and that's still millions of gallons a year. They likely don't need a fraction of that per carrier. Jetfuel is $4.50 a gallon or so from a 250MW facility. It could be $25 a gallon or more on a ship scale system, excluding the facility costs...

    So what? Carrier groups have to ship their fuel over sea using tankers that require escorts. $25/gallon might be cheap once you consider how much it costs to get the fuel to the carrier group.

  3. Re:Makes sense on US Navy Tries To Turn Seawater Into Jet Fuel · · Score: 1

    Making fuel from air/water is expensive, but If gas prices rise to $10/gallon and stay there, I bet we start seeing some large air/water to fuel plants being built.

  4. Re:But the beauty is on US Navy Tries To Turn Seawater Into Jet Fuel · · Score: 1

    While it would be impossible to retrofit a carrier, it probably would be possible to build a new fuel-ship that uses a miniaturized (yea, not available now, but that's why research is going on) version of the fuel generation system. It would probably still take a whole ship on its own, but that ship could travel with the fleet rather than having to make long journeys back and forth, requiring it's own escorts.

  5. Re:But the beauty is on US Navy Tries To Turn Seawater Into Jet Fuel · · Score: 1

    Civilian uses don't seem likely. Bio diesel uses more efficient processes to convert CO2 in the atmosphere to useable fuels. The work on GM algae that directly excrete usable fuels is very interesting.

    Actually, I read somewhere that if fuel prices reach around $7/gallon, it would become profitable to build an atmosphere/water to fuel plant that is powered by a multi-gigawatt nuclear reactor. This would be much better than using thousands of acres of land and millions of gallons of water to grow algae to make fuel. An air to fuel plant would only use, say, a hundred acres, significantly less water, and we wouldn't have to worry about viruses and bacteria killing/contaminating our algae culture.

    Also, as I understand it, photosynthesis isn't really that efficient in terms of incident light to chemical energy produced.

  6. Re:But the beauty is on US Navy Tries To Turn Seawater Into Jet Fuel · · Score: 1

    Yeah you did miss something. There are three pools of carbon to draw from, atmosphere (co2), ocean(dissolved co2), and subterranean(gas, oil, coal). The co2 in the ocean mostly is dissolved out of the atmosphere. If you extract co2 from the ocean and then release it into the atmosphere, it will eventually end up back in the ocean again. The total carbon in the atmosphere and ocean doesn't change. If you get carbon from oil/gas/coal, then you are adding carbon that has been sequestered for millions of years. The total carbon in the atmosphere and ocean increases in this case. That is why the former is better, even though it requires a lot of energy to de-oxidize co2 and turn it into fuel, the energy is from a carbon neutral source (nuclear reactor on the navy ship), so with this method overall levels of carbon remain constant.

  7. Re:Define deception? on Neural Networks-Equipped Robots Evolve the Ability To Deceive · · Score: 2, Insightful

    My dog knows that he can get away with doing things that he isn't supposed to do if I'm not looking. Sometimes I'll notice that he is staring at me from across the room... usually that means that he is up to something, and will try to do whatever it is if I look away for long enough. Sneaky little bastard.

  8. Re:Excuse me, but doesnt that define americans ? on Average Gamer Is 35, Fat and Bummed · · Score: 1

    Admittedly, I didn't RTFA, but I haven't seen anything that mentioned that gamers were more likely to be broke.

  9. Re:That's odd - I think games are boring on Average Gamer Is 35, Fat and Bummed · · Score: 1

    It also ignores bone mass. No, i don't mean *that* kind of bone. The ones that make up your skeleton. Ignoring the "i'm big boned" cliche, some people really do weigh more due to bone mass, even if skinny.

  10. So is FPS comming to EVE Online as well? on CCP Announces Console MMO Tie-In To the EVE Universe · · Score: 1

    I've heard that there is a "walk around in stations" change coming to E.O. Does that mean that once this is in place, you will have to be careful when walking around stations? I guess it might allow for station taking missions where you have to fight your way through the station. That could be cool I guess, But EVE is pretty complex as it is.

  11. Re:Nuclear Power on the Moon FTW! on NASA Developing Nuclear Reactor For Moon and Mars · · Score: 1

    Except that there is already naturally occuring uranium on the moon, so it is already "contaminated"

  12. Re:mmhmmm on NASA Developing Nuclear Reactor For Moon and Mars · · Score: 1
    RTFA...

    The recent tests examined technologies that would see a nuclear reactor coupled with a Stirling engine capable of producing 40 kilowatts of energy--enough to power a future lunar or Mars outpost.

    The 2.3 kw generator was just a test setup to prove the molten metal/sterling engine combo.

  13. Re:Screw it!!! on NASA's Cashflow Problem Puts Moon Trip In Doubt · · Score: 1

    I think that you are reading this as being a reaction-less propulsion drive... but that isn't what it is. It is just meant to counter torques created by aiming (rotating) instruments on a satellite.

    This is NOT a major breakthrough. All sorts of things already do this. For example, many automobile engines have a balance shaft that rotates a mass in such a way that it counters vibrations of the engine. This patent is just for a specific type of balancing device.

  14. Re:Scare mongering on NASA's Cashflow Problem Puts Moon Trip In Doubt · · Score: 1

    Also, usually you have to pay to get into popular high school sporting events, and some of that money goes to the sports team. THAT is the money that is typically used to buy new uniforms/equipment.

  15. Re:Dumb. on Will Your Credit Report Disqualify You For a Job? · · Score: 1

    That's what a credit score shows. It distinguishes those who are responsible with their finances from BOTH those who are criminally reckless AND those who are simply careless.

    Right...
    [sarcasm]
    For example it is careless of someone to be, say, parked on the side of city street and get slammed into by a drunk driver, which causes that person to be severely injured, such that they end up in the hospital for weeks, and then are stuck with physical therapy for months/years. It's totally reckless of that person to have an insurance policy that doesn't cover millions in expenses in a single year... I mean come on. They are only paying $1400 a month in premiums for that family policy, after all.
    [/sarcasm]

  16. Re:Dumb. on Will Your Credit Report Disqualify You For a Job? · · Score: 1

    Nope. If they can't afford medical help, they wait until the medical problem becomes an emergency, and then go to the emergency room. (In the US, every emergency room is required to provide care to stabilize any emergency cases that arrive, regardless of the ability of the patient to pay)

    So what happens is that the person gets enough care to get by for a while and then gets charged with a bill that they can't pay. The patient's credit rating gets knocked down due to this, and the hospital just has to eat the cost of stabilizing the patient. (ie: pass the cost onto others that CAN pay)

  17. Re:Games Are Boring on The Right Amount of "Challenge" In IT & Gaming · · Score: 1

    Out of curiosity, what types of TV shows and games did you partake in prior to giving them up?

  18. Re:Humans on 10 Worst Evolutionary Designs · · Score: 1

    Not when you kill your host. How many cancers do you know of that are highly contagious? And I don't count those that tend to be caused by viral infection.

  19. Re:Humans on 10 Worst Evolutionary Designs · · Score: 3, Informative

    How does their breathing tract move from their mouth, to another orifice?

    It didn't! Most animals breath mostly through their noses, not their mouths. The nostrils of the proto-dolphins migrated from the tip of the nose to the top of the head, presumably because being able to breathe while keeping your head level/pointed downward has a survival benefit... easier to see enemies/food/whatever swimming through the water, probably.

  20. Re:Details on benefits on What Questions Should a Prospective Employee Ask? · · Score: 1

    Seasonal jobs are just that. Seasonal. You don't get paid when you aren't working, thus it isn't vacation time. This discussion is about paid time off.

  21. Re:Cloud Computing on Chrome OS Designed To Start Microsoft Death Spiral · · Score: 1

    It definitely holds little value to business and industry because they like to retain control over there information and rightly so.

    Did it not occur to you that a large business operate their own secure cloud and connect all of their workstations to it instead of the google cloud?

  22. Re:Chrome isn't an OS on Chrome OS Designed To Start Microsoft Death Spiral · · Score: 1

    OK, so Chrome OS would be great for an appliance... except nobody is even contemplating building an appliance today.
    ...
    Sorry, but Chrome OS might be OK for a netbook. Maybe. It has no place on a desktop computer.

    Yeah, nobody is considering it... except the various netbooks that are coming out onto the market. Those are a small market now, but google is betting that netbooks will be a huge market. You yourself stated that for most people, a netbook would be enough to fulfill all of their needs, so why are you discounting that?

    Google isn't attempting to unseat windows/osx/linux in the high end workstation market. That will probably still be microsoft dominant for a long while, but there sure are a lot of low-end machines...

  23. Re:Start the Microsoft death spiral? What again? on Chrome OS Designed To Start Microsoft Death Spiral · · Score: 1

    That you are still growing does not guarantee that you are not on a path to oblivion. I think that the point is that despite their financial success, they are not prepared for the rise of net-books and cloud computing, and that this ill-preparedness will lead to their eventual collapse.

  24. Re:Windows will endure. on Chrome OS Designed To Start Microsoft Death Spiral · · Score: 1

    The important part would be that Chrome OS would likely be pre-installed, so there wouldn't be any significant hurdles for joe-sixpack to jump over before they can use it. Linux has always been "that thing that geeks use" that seems really complex to Joe and his buddies.

  25. Re:Interesting from an evolution POV on Neuron Path Discovery May Change Our Conception of Itching · · Score: 1

    for example, the vast majority of a human brain, or even the human DNA sequence, is unused.

    As I understand it, we DO use 100% of our brain, but not necessarily all at the same time.

    Also, many sections of so called junk DNA have been found to serve a purpose after all; usually in regulating how genes that are adjacent to it are expressed. That probably isn't the case for all of it, but I doubt that it will be possible to say that "the vast majority" is junk.