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Comment Re:Now that is a ridiculous example (Score 1) 152

At this point I'm suspicious that you're pulling my leg, I'm not sure how anyone could get so worked up over a post regarding battery vs hydrogen storage. However, if what I said was factually wrong and you are an expert, go ahead, convince me. Use facts. Use numbers. Put links, I'll read them. I'm not some partisan idiot like you apparently believe I am. So go for it, give me the benefit of your expert knowledge and experience.

Comment Re:Now that is a ridiculous example (Score 1) 152

A suggestion that batteries (or insert any other "green" technology you with to attack instead) are useless because they cannot single-handedly supply a days worth of electricity for a nation the size of the USA is not ridiculous and not a politically motivated move? So you are calling me stupid or gullible as well? WTF is it with this political luddite shit. Something doesn't have to be the "one true energy" that can do everything for it to be useful.

Relax for a minute, I'm afraid you're going to pop a vein. If you'll read my other posts in this topic, I think you'll find that I'm pretty positive with regard to "green" technology. I simply pointed out a potential advantage of hydrogen compared to batteries. I think you're getting offended over nothing.

Also ask a high schooler to tell you about electricity grids and time zones. Distributed generation capacity that can be turned on and off as required are vastly less lossy than any sort of storage, and since you have a grid the size of a continent that peaks are spread so storage isn't so necessary anyway. When New York needs power for an evening peak Texas isn't using a lot.

Instead of pretending you know everything, I suggest you read up on energy storage with regard to attaining high penetration of renewables. In every study I've read, the authors assert that we need much much more storage and that a variety of technologies work better than a single technology. Read my post again, the battery calculations I made were meant to display the scale of the problem and compare it to where we are today. It's pretty obvious that's what the intent was unless you're really trying to put words into my mouth.

Let me stress that I'm not at all offended by you branding me a "luddite" I think it's pretty funny actually. But how about instead of calling me names you go read up on energy storage and argue with facts?

Comment Re:Now that is a ridiculous example (Score 1) 152

Wow there, take it easy. This wasn't a political post, I'm simply discussing energy storage in the context of generating 100% of electricity from renewable sources and using algebra with order-of-magnitude thinking to show the magnitude of the solution needed. In any case, I'd like to know exactly why you believe my example is "utterly ridiculous."

It's not exactly clear how much storage would be needed to achieve 100% renewable energy. The more storage we have, the less generation capacity we need for cloudy days or low-wind days when each power source produces less energy. Conversely, the more excess capacity we have, the less storage is needed because it power could be transmitted over long distances from places with excess capacity to places with non-ideal weather conditions.

Comment Let's do some algebra (Score 2) 152

OK, let's do some algebra.

The mass of the atmosphere is 5.15E18 kg, 20% of which is oxygen, or ~1E18 kg. A day's worth of grid storage for the US is ~11TWh. Hydrogen has an energy density of 33.3 kWh/kg. So 11TWh is 3.3E8 kg of hydrogen. Hydrogen is 1/16 the mass of oxygen, so an equivalent mass of oxygen would be 5.29E9kg, however one molecule of hydrogen is produced per 1/2 molecule of oxygen in water splitting, so the mass of oxygen generated would be half that, 2.64E9kg. So to make enough hydrogen to store a day's worth of electricity for the US, we'd have to increase the O2 concentration of our atmosphere by 2.64E9/1E18 = 2.64E-9 (0.000000264%).

I think we'll be OK. Also, keep in mind that cars consume oxygen yet we generally don't die from lack of oxygen when standing by a busy intersection.

Comment Re:H2 is actually gaining (small) market presence (Score 1) 152

Well, we have to solve the storage issue before renewables can take over anyway. Batteries are still a long way from being viable for grid-scale storage. One day's worth of energy in the US (which we would want to store due to the intermittent nature of renewable sources) is around 11TWh. Take for example Tesla's GW battery plant that will make something approaching ~35GWh/year worth of battery storage. At that rate it would take 11TWh/(0.035TWh/year) = 314 years to produce a day's worth of grid storage in batteries. Hydrogen is energy stored in chemical bonds, so hydrogen storage is in some ways an easier problem to solve than making countless batteries.

Comment H2 is actually gaining (small) market presence (Score 5, Informative) 152

A couple years ago I'd have agreed with you, but a lot has changed.

Toyota unveiled a (admittedly very expensive) hydrogen-powered car that goes >300 miles on a charge and takes 5 min to refuel. Toyota, the largest auto manufacturer in the world, is probably not doing this as an empty gesture. They've announced they'll almost eliminate ICE cars from their lineup by 2050 and have yet to release an all-electric car (just plugin hybrids). They're working with Shell to provide fueling stations, of which there are >80 in Japan and 25 in CA right now, promising 160 in Japan within a couple years.



Hydrogen can be produced via electrolysis of water or salt water from any source of electricity, including intermittent sources like renewables. The efficiency of electrolysis is very high today, approaching 90%.


It's not a perfect answer, but it's looking a lot less ridiculous than it did a few years ago.

Comment Yes they are, but for a different reason. (Score 1) 296

Yes, they are a threat. However, I doubt they could get their subs anywhere near America. Those old noisy subs would be detected and destroyed.

They are a threat because they could easily bomb Seol and kill millions with the flick of a switch. They have lots of missiles and dug-in defenses right next to the DMZ, which is also riddled with huge tunnels for transporting armaments and troops. If they attacked Seol it would result in a massive bloodbath, America would step in, China would fight back to keep their buffer state and it could spark WWIII. China doesn't want WWIII, nor does the US. They are working to tone things down (hopefully somehow remove Kim in the process) so that they can keep a buffer state between China and South Korea, a US ally.

For those saying "ignore DRPK" you are ignoring the danger. If the regime gets deliverable nukes they will blackmail all countries surrounding them for money, food, resources and could then actually become a real international power. If you think they won't do it, remember how sane and rational Japan is, yet they justified the attack on Pearl Harbor because we wouldn't sell them fuel or steel.

Comment Apple IIc+ (Score 1) 857

Apple IIc+

Won it in a contest. You'd put a program (word processor, game, etc) into the 5.25" floppy drive and turn on the computer to load it. I had such classics as "lemonade stand," "introduction to Apple IIc+," and some maze game where you move a dot through a maze while avoiding another dot that represented a horrible ogre. I think there were a few more, but it's been a while. Also had a dot matrix printer.

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