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Everything posted by coreview2

  1. I've seen a lot of bs from a lot of sources and all stirred in a pot of politics which is also from many sources. The one thing I find more revealing is that when I read directly from researchers papers or web sites, healthy scientific skepticism is very much alive on both sides of the issue. That's a good thing. It tends to be the journalists and political activists who preach on either extreme as though it was a religion. When I read into Mann's "hockey stick" which is the primary launch point of much of the political frenzy, I can't help but notice that the Medieval Warming that is so well documented in recorded history is missing. That bothers me a lot. I like history and have for quite a few decades. Then too there is the fact that Vikings were farming on Greenland for quite some time. My favorite question to ask is: If we had a simple thermostat that could change climate, based on the reliability of the models, should we chose to do so now? My biggest doubt is the computer modeling. There are just too many unknowns in the soup and reliability on post predicting known climate is sometimes almost silly. Then too use of data that has the smell "form fitting" about it.
  2. Is there a difference between the forces of negative pressure (air being kept out) and the forces of hot air held in (air being kept in)? Is this not approximately the the inverse? The thing had no trouble lifting off with hot air and the very thin bag didn't rupture (displacement did of course change so it was not exactly equal in those terms).
  3. http://economy.okstate.edu/papers/economics%20of%20deep%20drilling.pdf Here's a good link on the cost of deep drilling. The average cost of drilling 17,585 feet deep was $2.65 million from 1995 to 1999 (1,221 wells). Some of the wells have gone to 30,000 feet! The cost of drilling has actually gone down quite a lot due to improved technology and techniques and given the coming advent of laser drill heads there is great promise that the curve of improvement will make great strides. The big cost will be off-shore drilling, but at least there would be no danger of a big oil spill and the 70,000 KM of tectonic rift has millions of vents where sea and air meets fresh magma all of the time. Of course, a few pilot plants would be in order and I don't think that they should be done in subduction zones or near non-rift side faults. The pilot plants alone would provided a great deal of new scientific information about the 99% of our planet that is molten and above 1000C.
  4. Actually building the thing and feeling it get very, very light with negative pressure (a couple of minutes of vacuuming air out of the construct), it really didn't feel like it was so far from floating. Then too, the broken, but un-punctured remains did float very quickly when I pumped hot air into it with a hair drier. That's the real world "lab test," primitive though it may be. One of the things that a cad simulator could do would be to define with good accuracy what kind of strength, weight and materials would be needed with various design configurations (even if such materials were yet to be designed) to achieve the best combination of buoyancy and strength. Again the advantages would be substantial for long term and very high altitude balloons which lose helium and suffer the effects of gas expansion and contraction (which is a big part of the reason NASA can't keep them up there that long).
  5. I used to be a big fan of dry rock geothermal and have followed it for years. I still think it is a great idea. It will certainly work in some areas, but as mentioned there are problems with the nature of the heat exchanger being shattered rocks. Perhaps when drilling is a lot cheaper thanks to the coming use of laser drill heads, it would be possible to construct a very deep closed loop rather than shattering the rocks and hoping that it didn't cause an earth quake (as happened to the Swiss pilot project recently) or as in the case of the Japanese project, a lot of the water simply leaked out somewhere. The concept does work, but it is not a 100% sure bet until the heat exchanger problems are solved (the sure bet part being very important to its investment climate). Also, note that dry rock heat resources become exhausted over a couple of decades or so as the rock cools and it is projected that it would take a few decades for them to re-heat. Drilling directly into magma has some serious advantages. Once the the hole is drilled through to magma, the heat exchanger can be a pipe loop that is "merely" inserted (no more drilling at least). The quality of the energy there is about 1000C and would with be a permanent source given sound study, testing and planning. 1000C is ideal for massive hydrogen production via thermochemical process which is by far the most efficient. Heat to usable energy conversion is in the 60% range given electric co-gen along with hydrogen production (according to Argonne National Lab). In the future magma heat mining would offer a very high grade energy source capable of producing vast quantities of hydrogen and electric power from facilities with a small environmental footprint, producing no emissions and with no waste to dispose of. It is the ultimate source of baseline power that does not require anything more than contemporary technology to develop. The link I had breaking down very clearly the current range of thermochemical processes no longer works, but it is not hard to see the advantage of a 900C+ source of heat. http://www.cmt.anl.gov/Science_and_Technology/Fuel_Cells/Nuclear_Hydrogen_Production.shtml Note the massive blue area on the US Geological Survey chart of crustal thickness. I also note that drilling for gas in Oklahoma sometimes results in striking molten material even where the average crust is 40KM thick and the drilling on 5 or 6KM (only Of course, I'm not suggesting that location isn't important or that magma heat mining can solve all of our energy needs, just that it's potential dwarfs all others given the fact that 99% of our planet is molten and above 1000C. http://earthquake.usgs.gov/research/structure/crust/crust.php
  6. Neat little experiment. One of the reasons I like shallow dives in scuba! Still is not a 13% reduction in air equivalent to being under 3.9 feet of water in our case? I after the structure collapsed, I did one more thing. Using a hair drier in the vacuum port, filled it with enough hot air to make it float. Of course, it went right up then.
  7. I can see industrial grade solar working very well in Arizona and New Mexico or Australia, for example, where there is lots of sun and a lot of land isn't used to grow things. However, solar has a very big footprint and I'd rather see it in an adjunct role as the roofing material of choice for suburban and rural homes and facilities for less than arid places. I've followed the Aussie geothermal plants for some years as well as the concept. However, the one in Switzerland recently caused a minor earthquake and one in Japan loses its water. Guess that's why pilot plants are built. Advances in drilling (laser drilling for one) and seismic imaging are great assets for this and ultimately for magma heat mining. http://www.lanl.gov/orgs/ees/ees11/geophysics/other/hdr.shtml For a bit of history, Fenton Hill from Los Alamos was the first HDR pilot built.
  8. Something doesn't feel right here. Removing 1.3 pounds of air from 128 cubic feet (10+ pounds) results in a half a ton of pressure? The pressure was indeed far more than expected, but it was only a vacuum cleaner that sucked the air out (albeit it could pick up a bowling ball). This is only an intuitive "feeling" kind of thing, but that construct got to the point just before collapse that it could be lifted with a delicate touch of two fingers whereas before that would have not been possible. One's sense of lift gets very good after handling a thing for a couple of weeks.
  9. The Town Gas system supplied almost all of the Northeast and much of the country for nearly 100 years. The history is pretty well recorded. Wiki has a good overview. http://en.wikipedia.org/wiki/Town_gas It ain't a clean process. In fact, most of the process itself and the energy spent is spent cleaning up the nasty stuff in the result of incomplete burning of coal. I'm most happy to see bio-waste, fall leaves, land-fill and such used to make fuel, however, it will only be a niche in the overall picture of energy needs and we really need to get beyond the Fossil Fuel age and hydrocarbons as soon as practical. Then too I'm more than a little concerned that some of those bacteria that are used to digest cellulose are E Coli (yes the very same that live in our gut and without which we cannot digest our food). One of the reasons E Coli is used in so much research on gene-splicing is that it was so well studied as a bacteria because it has a symbiotic relationship with our bodies. That's a short-cut that worries me.
  10. If you look at history you will find that we did indeed handle hydrogen for many decades in the form of Town Gas or Coal Gas. Town Gas is a mixture of hydrogen and carbon monoxide resulting from cracking coal and it was used for cooking, heating and lighting up until the early 1950's. For the last decade or so, all new gas pipelines have had to be hydrogen ready by federal law. The last coal gas plant in the US Northeast shutdown in 1955. From what I've read in studies on that side of the topic, hydrogen does pose problems for delivery and transport, but they are neither impossible nor uneconomical. This is in part due to the presumed use of hydrogen in fuel cells where efficiency is very high and not burning it in very inefficient internal combustion engines. It takes about 1/3 of the energy delivered to convert hydrogen to LH2.
  11. As long as the reactors are truly meltdown proof, idiot proof and unattractive to terrorists, they should have big role. I like wave power but not too many of the designs I've seen. The best concept I've seen so far was a simple float anchored to the bottom with the up and down motion driving a generator. However, magma heat mining has vast potential that dwarfs all others. While most of Earth's crust is 5KM thick, there is quite a bit that is much less and if you are making hydrogen it doesn't really matter if it is real close to the market. While a lot of the very thin crust is not ideally located near major cities, a good bit of it is within transmission range much as NY gets a lot of power from Canada. Super conductors would be a big help! Then too the technological means of seeing geology with seismic imaging is quite advanced and would be likely to find some choice spots as close as possible to electric consumptions markets.
  12. Building cad models I can do as I have Maya. However, Maya is an animation program and not an engineering or physics simulator. It does have a physical dynamics package, but it is gear to special effects not realistic simulations. There must be a program out there that could allow for the testing via simulation of many design concepts. In designing the structure, our original idea was a sphere, but again we didn't have the time to build it and getting the balsa to bend would have taken a different kind of cut than we had ordered (thin layers laminated most likely). Skinning it was possible, but would have taken more time too. A good cad simulator would allow designs to be tested and if it was reasonably accurate would help provide clues as to where various designs would likely fail. Also, a simulator would allow for bigger models to be tested. The link below is to the "Physics Balsa Bridge Building Contest", but a negative pressure balloon would be more fun ) http://www.balsabridge.com/
  13. Anyone have any other suggested new sources of energy that would qualify as both clean and baseline power (non-intermittent, reliable and sustainable too). I'm not sure Mr. Fusion is going to happen any time soon as a practical matter and the process does produce radioactive waste.
  14. I'd love to find someone who has access to an appropriate engineering cad simulator who was willing to test the concept of a negative pressure blimp. cheers,
  15. Oh don't get me wrong, I don't think one-size-fits-all is anything other than a classic government-like mistake, but I think the criteria should always be that the thing is literally melt-down proof, fire-proof, idiot-proof and unattractive to terrorists as well. I saw some Thorium breeder directions that were interesting too. The fail-safe in that direction is melting plugs that drain the chamber. Still the ceramic coated pebble-bed's great appeal is that civilization could fall into the dark ages and the plant left unattended without catastrophic consequences. In any event, it appears to be a good place to start as it is a very politically viable concept completely purged of political clouds of Chernobyl or even Three Mile Island.
  16. I guess I'd worry about any system with the potential for very high risk that relies on intervention to make it stop. Systems fail. People fail. If I understand the GA pebble-bed (gum-ball machine) correctly, no matter what happens it cannot meltdown, or burn. If it is left sitting there with the switch on and all loss of coolant/heat exchanger, it will not melt-down or release anything. I think this is politically very important. I also like the potential of the gum-ball machine refueling. The balls are churned and randomly tested so when they are spent, the "pin-ball" machine drops them out and a new ball is added. Very elegant concept.
  17. Roger that. We knew it would be weaker, but it felt pretty strong for something so very light. Just didn't realize how strong the pressure would be. It would be a great experiment for an engineering CAD/sim program!
  18. I don't like the South African design because unlike the General Atomics design the pebbles or gum-balls are not ceramic coated. They just presume that no air in the thing keeps it fireproof. The GA version really is meltdown proof because it doesn't matter if air gets into the chamber or if the chamber spills out. However, if I'm reading it right, the South African one could have a major Chernobyl like event given air leaking into it, something like a terrorist attack or big human error. The Russian reactors used graphite as the modulator also and Chernobyl was what happened when the graphite and core got exposed to air. Someone please correct me if I'm wrong or overly vague on the details. Good questions. Beyond what's available on the web, most of what I know on the GA design is from a nuclear engineer that passed through the NYTimes science forums a few years back and it is my understanding that most of our waste volume is low-level waste. Is there a radioactive helium? I don't know. I do like the elegance of General Atomics design however. The inherent meltdown proof nature of the plant should mean that they are ultimately a lot cheaper to build and operate and politically the safety factor eliminates about 90% of reservations about nuclear power.
  19. The breakage happened mostly near the most reinforced joints. A soccer ball concept with I-beam balsa might have been a good compromise over the classic Roman arch and a lot easier to construct. Even as it was, it felt like it was strong enough, but the thing that surprised me was the amount of stress removing a pound or so of air actually caused! Again, ideally, it would be best to test this concept in a simulator where many variations in design and materials could be subjected to stresses. Ultimately for NASA or such, perhaps a negative pressure combined with helium would be the best solution. Helium under negative pressure would weigh even less.
  20. The tricky part is that it is hard to get balsa in long lengths that do not have serious weak spots (by experience on this). We did attempt to bend it to a sphere, but it was very time consuming as the wood needed to be thin strips that were laminated together to make it curve and then too we wanted to make an I-beam kind of balsa struts. We built the skin from very large dry cleaning bags after much searching for something very thin and very strong. We cut the bags apart and used Scotch double face tape for the seams. That part was more than adequate and the weight was very small. Again the whole construct weighed in around 1.25 pounds (on a reasonably accurate postal scale). In any event, it was a lot of fun to try for a world first! http://s113.photobucket.com/albums/n219/coreview2/?action=view&current=VB03.jpg
  21. I think that when politicians have their heads in the pork barrel, they may as well not have a head. Corn and food as an export is one of our big pluses on balance of trade, burning it in gas tanks at a time when the dollar is weak seems doubly foolish. We need some real solutions to oil and fossil fuel dependency, not pork-barrel logic devoid of foresight. I think we need a lot more engineers in Congress because we have way too many lawyers there. Lawyers think in terms of words and their product and their victories are all in the land of word processors.
  22. My thinking exactly. Even with our crude balsa and poly structure, it very nearly did work. Here is a picture of our experiment. Again, we wanted to make it a big sphere with i-beam like balsa for the ribs, but found it beyond the three weeks of free time we had to play with this idea. It makes a lot of sense, but again the way to do it is to have a simulator where designs can be built and tested in a computer quickly before spending weeks gluing balsa. It would make a great classroom experiment or competition.
  23. While that is true, if you note, there are plenty of places where the crust is 0 to 5KM thick and there are places like Iceland where very thin crust (plate rift) runs right under it. Given the vast scale of the "blue" (5KM) part of the global crustal chart, do you not think that seismic imaging could not find some very choice spots? Interestingly, while reading up on drilling, there are deep gas wells in the US that have hit molten material. Perhaps this is a case of functional fixedness, but it is ironic that an energy company finds a trove of energy (molten material), but it's not NH4, so its bad news. There is a major disconnect there somewhere. Because the designs use helium as an exchange medium and helium as an inert gas cannot become radioactive. In light water reactors, water itself becomes a very large quantity of low-level radio active waste. http://gt-mhr.ga.com/ At the start of the 21st century, most of the electricity consumed in the U.S. and the rest of the world is still being generated by the burning of fossil fuels. Even larger quantities of fossil fuels are being burned to meet other demands imposed by the residential, commercial, industrial, and transportation sectors. In 1999, the U.S. imported 58% of its crude oil and 37% of its total energy supply, and burning fossil fuels in the U.S. resulted in the emission of 11.3 million metric tons of sulfur dioxide, 4.9 million metric tons of nitrogen oxide, and an astounding 1510 million metric tons of carbon dioxide. It is clear that a new energy policy must address these environmental, economic, and energy-security concerns. With recent technological advances, a strong case can be made to include nuclear energy as a major component of a 21st-century energy policy. The GT-MHR combines a meltdown-proof reactor and advanced gas turbine technology in a power plant with a quantum improvement in thermal efficiency. . . approaching 50%. This efficiency makes possible much lower power costs, without the environmental degradation and resource depletion of burning fossil fuels Efficiency from thermodynamics Conventional, low-temperature nuclear plants operate at about 32% thermal efficiency. GT-MHR power plants can achieve thermal efficiencies of close to 50% now, and even higher efficiencies in the future. • 50% more electrical power from the same number of fissions. • Dramatically lower high-level radioactive waste per unit of energy – today’s reactors produce 50% more high-level waste than will the GT-MHR. • Much less thermal discharge to the environment. Plants can use air cooling, which allows for more flexible siting options.
  24. Beyond intermittent sources, efficiency and conservation savings, we still have to have very solid base power. Given the coming emergence of primarily electric drive vehicles, a lot more electric power will be needed. My sense is that base power should come from two new sources. 1. Meltdown proof pebble-bed nuclear reactors are one viable answer that I'm amazed has not been "discovered" by the lawyers or others in Congress. They are about 50% efficient, truly meltdown proof, and because they use helium as the heat exchange medium they greatly reduce radioactive waste. It is a very elegant design. 2. Magma heat mining. 99% of our planet is above 1000C and most of the world's crust is around 5KM thick (see the USGS chart below). The world's deepest holes drilled are around 12KM and there are thousands in the 5KM range. The basic concept is to put a pipe loop directly into liquid magma as a heat exchanger in a binary power plant or to use for thermochemical hydrogen production (50%+ efficient). There is nothing really new in the technology except that drilling with laser is int the near future with great promise and seismic imaging allows us to "see" ideal locations. There are many places like along the 70,000KM of tectonic rifts where new crust is forming constantly, that Earth's crust is very thin. Magma heat mining would dwarf all other sources except Mr. Fusion. It would have a very small environmental footprint, no emissions and no waste to dispose of. crustal thickness
  25. Aerogels? Do tell. It was a lot of fun building it and it did get very, very light, but alas we needed to build it as a spherical shape -- though that would have taken more free time that we had. NASA has a very hard time keeping big balloons up for a long time and the design of a vacuum balloon would potentially solve most of the problems of Helium balloons if it were worked out. Helium is a very small atom and it is hard to keep in especially with a very thing and light weight membrane. Also as a gas it expands and contracts quite a lot especially at very high altitude due to very intense sun and very cold nights. Also, once ballast or helium are released, there is no control over altitude. A vacuum (negative pressure as buoyancy), unlike helium is is not trying to use a very thin membrane to keep a very small atom in, but keep air's larger molecules out. A vacuum is also not affected by temperature change so there would be no significant expansion and contraction. A vacuum is also a controllable thing given an energy source and pump that can be increased or decreased. Having balloons that stayed in the upper atmosphere for months or years would be of great value.
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