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Comment Not too surprising (Score 5, Interesting) 164

Someone else (who I think I saw here on Slashdot the last time Voyager was mentioned) had a great analogy for what we're likely seeing. I can't take credit for this at all, but I think it makes a lot of sense.

Suppose we're a small probe, making our way off an island, down the beach, and into the ocean. All we have is a wind-speed detector, and a water detector. As we near the water, waves start lapping over us. When they do, our wind-speed detector says "no wind", and our water detector says "we're wet." Have we entered the ocean yet? The answer is "not quite, but we're really darn close."

It doesn't seem surprising to me at all that the boundary neither perfectly uniform, nor stationary in time. I think we'll be in this transition band for a while.

Comment Re:not to sound picky (Score 1) 96

I realize you're cherry picking the NASA buy, but I'm pretty sure Google is acting on self interests alone. Even if you choose to believe that NASA picked up the phone one day, and a bunch of politicians on the other line said, "Hey NASA, buy this thing from Canada, cause that would be awesome!" I bet that kind of simplistic worldview makes their scientists and mathematicians feel awesome.

Comment Re:Chinese Hosting (Score 1, Insightful) 165

More importantly, why should you be on the defensive? Isn't it good to know both things? Is it somehow a binary choice between wanting to know about the two issues? Snowden is the messenger, not the message, and you probably have a higher likelihood of impacting domestic policy than raising awareness to the 'scandal' that is foreign governments trying to disrupt or influence local politics. Especially since it doesn't take any tinfoil whatsoever to discuss USA's storied history of doing the same. This strawman of somebody who thinks that China would never stoop to what the USA stoops to all the time is pretty hilarious. This is what governments do, the world over. The idea that the USA isn't doing this, or wouldn't do it in the future is downright silly given the history of unilateral foreign interference by all world super powers.

Comment Re:A so-called "Hydrogen Economy" is petroleum fue (Score 1) 559

Hydrogen is not a power source, it's an energy storage medium.

I have never liked this line of argument. After all, it's essentially true of gasoline, too; it's just that nature did the work. (And, in a lot of cases, the hydrogen is mined too; yay natural gas.) Both are chemicals which are oxidized to release heat energy. If the meaningful difference is whether nature or we did the work, then they're both storage media.

You go on to cite energy capacity differences; those are only meaningful in apples to apples comparisons.

Any line of reasoning that assumes hydrogen is a power source - rather than just a storage medium with very poor energy density - is unfortunately based on a flawed premise.

I don't think this is actually correct.

Where do you find the actual meaningful difference to be? It's apparently not in that they're both exothermic chemistry based on the same element.

Other power sources aren't even remotely similar - eg nuclear, wind.

Why are two things that are virtually identical being seen as distinct? Is the issue whether nature put the power in instead of us? Is the difference between a power source and an energy storage medium found solely in whether you primarily imagine our having to put energy in to make them viable?

Does gasoline become an energy storage medium, despite zero actual changes, when they start sourcing it from CO2 in the atmosphere?

What is the meaningful net effect of being in one category or the other? You seem to be suggesting that the problem isn't just the energy density (and that in itself is misleading in many ways,) but rather a more sophisticated issue of whether it's a source or a medium - and that that is what's undermining their thought.

You can get hydrogen out of the ground, and you can spend energy to manufacture gasoline from the air, both today. If they're both sourced that way, does that mean that the lines of reasoning you're whargarbling at without actually showing an error, merely stating that there is one, suddenly become more ratified?

What if it happened to cost as much energy to get gasoline out of the ground as is received by burning it? That isn't the case today, but someday it will be, unless we stop using it. On that day, will it have become an energy storage medium?

Is the line about whether we have to invest energy to derive energy from it? Because calling something an energy storage medium based on how much power it takes to acquire seems ridiculous to me, as much so as does classing one chemical exothermic with nuclear and wind but against another chemical exothermic based on production rate, but I can't see any definition that seperates the two that doesn't end up with that apparent nonsense result.

Why is it that so many hydrogen cars and busses are actually doing well, if it's such a flawed premise?

Why are you measuring energy per liter? Liter is a unit of volume. The amount of energy per liter here is a direct function of pressure. No mention is made of pressure in two of the three cases.

Cryogenically stored? Room temperature? The temperature of the hydrogen or gasoline has virtually nothing to do with the amount of energy released by burning it.

Where did you get these numbers? They don't agree with the ones on Wikipedia. Granted, I'm a Wikipedia skeptic; if you can cite a valid source I'm happy to take it, but I remain somewhat doubtful that you'll be able to.

The proper measure here is not the energy density; that is and always has been asinine. The proper measure here is the specific energy - that is, by weight, not by volume. Hydrogen doesn't become a better fuel (oh sorry, "energy storage medium,") just because you put it under pressure. That's ridiculous. What matters is how much energy you can carry by weight, allowing for a practical limit on storage size. Hydrogen as a whole is not meaningfully better as a storage medium every time you learn to make an improved storage tank.

Hydrogen cars have worked very well for 30 years. They're cheap, they're efficient, and they let us move the burden of production to better controlled sources than a small engine. And no, that's not because of some phantom line between media and sources; the same thing would be true if you chose to distill gasoline from the air, which many people are doing, just not yet at market cost. If gasoline is both a fuel and a power storage medium, then I submit to you with respect that the distinction is masturbatory garbage, and does not in fact exist at all.

The real problem with hydrogen cars is simple: you can't get fuel just about anywhere you go. Chicken and egg.

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We must believe that it is the darkest before the dawn of a beautiful new world. We will see it when we believe it. -- Saul Alinsky