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#11
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Alternative to the Battery wows?
"water vapor comes and goes with the weather."
Yes, but now we are talking about combusting H2 with O2, which is an entirely new source of H2O vapor. And, if you want another little problem to solve with the storage and use of hydrogen, look up "Hydrogen Embrittlement." I'm not saying it won't be feasible, but it isn't by any means a magic panacea. In his book, "Skunk Works," Ben Rich talks about Lockheed's experiments with producing and storing liquid hydrogen in the 1950's for possible use as a fuel for high flying, Mach 3+ reconnaissance aircraft. The chapter is titled "Blowing Up Burbank." (That should give you a hint.) Their conclusions were that it was terribly inefficient due to the size of the storage vessel needed for acceptable range, it was very dangerous to transport and store and the infrastructure needed to ensure availability around the world would cost more than the rest of the program, including development of the aircraft and training Air Force personnel to handle it. They went with a new fuel (JP-7) and built the A-12, followed by the SR-71. |
#12
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Alternative to the Battery wows?
On 3/8/2021 6:10 PM, Mark Mocho wrote:
On Monday, March 8, 2021 at 1:42:45 PM UTC-7, Eric Greenwell wrote: Mark Mocho wrote on 3/8/2021 11:34 AM: And I seem to remember hearing that water vapor is more of a "greenhouse gas" than carbon dioxide. Not so much when it comes to climate change, because as water vapor increases (primarily due to global warming), it forms more clouds, which reflect the heat, tending to reduce global warming - all part of a natural cycle that's be going on since the earth began. CO2 does not condense, and we are adding it to the atmosphere at a far higher rate than natural carbon sinks can remove it. -- However, using hydrogen as an alternative fuel WILL add to the amount of water vapor in the atmosphere. Note the following statement: "...water vapor is the largest contributor to the Earth’s greenhouse effect...However, water vapor does not control the Earth’s temperature, but is instead controlled by the temperature...If there had been no increase in the amounts of non-condensable greenhouse gases (like carbon dioxide), the amount of water vapor in the atmosphere would not have changed with all other variables remaining the same." (from the American Chemical Society's ACS Climate Science Toolkit) The key phrase is the last one: "with all other variables remaining the same." Imagine that instead of seeing "normal" contrails behind a high flying airliner, there is a huge plume of water vapor that results from burning hydrogen. That definitely adds to atmospheric water vapor, independent of the natural evaporation/condensation cycle that forms clouds. Of course, the "Chemtrails" paranoids will get a corresponding boost in popularity. Naaah, to "make" the hydrogen you'd need to separate it from water. It's a closed loop. There are many hurdles, but this one is not. Of course you can separate it from methane (natural gas) instead, but if you burn the gas directly you get the same water vapor. I find the subject line of this thread appropriate though, there are too many "wows" out there but the "vaporware" never materializes. |
#13
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Alternative to the Battery wows?
Mark Mocho wrote on 3/8/2021 5:12 PM:
Yes, but now we are talking about combusting H2 with O2, which is an entirely new source of H2O vapor. Yes, a new source, but it doesn't accumulate in the atmosphere, as the additional water vapor will condense. CO2 does not condense, and lingers for hundreds of years. -- Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me) - "A Guide to Self-Launching Sailplane Operation" https://sites.google.com/site/motorg...ad-the-guide-1 |
#14
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Alternative to the Battery wows?
That's terrific! The energy content in H2 beats anything except nuclear
power, and wouldn't it be great to fly a 72 ton glider around with unlimited launch and retrieve capability? But one statement in the article has me perplexed: "Current hydrogen extraction is highly energy intensive, so ways to harvest “green hydrogen” using water electrolysis are being explored." I believe that it takes more energy to extract the hydrogen from water than is realized by burning the hydrogen. I have no idea of the energy cost to liquefy and distill hydrogen. Can anybody shed some light on that? I can see giant smoke stacks spewing sooty black smoke into the air due to burning coal to generate the electricity to compress the air to harvest the hydrogen. Well... Maybe not. Perhaps covering Europe with wind mills to make the electricity and using sailing ships to deliver the H2 around the world. Credit to Dr. Seuss and Rube Goldberg for the inspiration. Dan 5J On 3/8/21 11:26 AM, AS wrote: Ran across this short article about an interesting project at the Delft University in The Netherlands: https://www.yahoo.com/lifestyle/dutc...153606032.html Uli AS |
#15
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Alternative to the Battery wows?
On Tuesday, 9 March 2021 at 16:24:12 UTC, Dan Marotta wrote:
That's terrific! The energy content in H2 beats anything except nuclear power, and wouldn't it be great to fly a 72 ton glider around with unlimited launch and retrieve capability? But one statement in the article has me perplexed: "Current hydrogen extraction is highly energy intensive, so ways to harvest “green hydrogen” using water electrolysis are being explored." I believe that it takes more energy to extract the hydrogen from water than is realized by burning the hydrogen. I have no idea of the energy cost to liquefy and distill hydrogen. Can anybody shed some light on that? I can see giant smoke stacks spewing sooty black smoke into the air due to burning coal to generate the electricity to compress the air to harvest the hydrogen. Well... Maybe not. Perhaps covering Europe with wind mills to make the electricity and using sailing ships to deliver the H2 around the world. Credit to Dr. Seuss and Rube Goldberg for the inspiration. Dan 5J On 3/8/21 11:26 AM, AS wrote: Ran across this short article about an interesting project at the Delft University in The Netherlands: https://www.yahoo.com/lifestyle/dutc...153606032.html Uli AS It looks like covering Saudi Arabia with solar panels is the way! https://tinyurl.com/3kjwd6nf |
#16
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Alternative to the Battery wows?
On 3/9/2021 11:23 AM, Dan Marotta wrote:
That's terrific!* The energy content in H2 beats anything except nuclear power, and wouldn't it be great to fly a 72 ton glider around with unlimited launch and retrieve capability?* But one statement in the article has me perplexed: "Current hydrogen extraction is highly energy intensive, so ways to harvest “green hydrogen” using water electrolysis are being explored." I believe that it takes more energy to extract the hydrogen from water than is realized by burning the hydrogen.* I have no idea of the energy cost to liquefy and distill hydrogen.* Can anybody shed some light on that?* I can see giant smoke stacks spewing sooty black smoke into the air due to burning coal to generate the electricity to compress the air to harvest the hydrogen.* Well...* Maybe not.* Perhaps covering Europe with wind mills to make the electricity and using sailing ships to deliver the H2 around the world. Credit to Dr. Seuss and Rube Goldberg for the inspiration. Yeah, the wide-eyed talk about hydrogen being "the most common element in the universe" is pure nonsense. There are no "hydrogen wells" on our planet. It's an energy carrier, not an energy source. And it's not a good energy carrier, since it leaks through everything etc. You can use natural gas or other fossil fuels to produce hydrogen from other materials. Or solar. But currently it's mostly natural gas. And yes it uses more energy to "produce" than you get from burning it. Or even from using it in fuel cell$. About 4x more, all told, relative to using electric power directly. But the "hydrogen economy" rah-rah seems to emerge from the shadows for another round every decade or so. Then it goes back into the shadows to keep fusion energy company. If the issue is what to do with surplus solar or wind energy, in the (few) times and places where it's available, there are many other ideas, including the production of liquid fuels which are much more practical than hydrogen. Methanol and ammonia are some I've heard of. Yes they are toxic if spilled. So is gasoline. At least you know when there's a leak. |
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