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Pelayo
Skeptic Friend
USA
70 Posts |
Posted - 02/28/2008 : 17:55:11 [Permalink]
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This just in:
What do you do when there is nothing blowing in the wind, not even the answer:
Link
Edited to fix overly long link.
Kil |
I have a habit of posting without reading all previous comments, if I am repeating someone, well, excuse me, please.
"No tendency is quite so strong in human nature as the desire to lay down rules of conduct for other people." - William Howard Taft
"God ran out of new souls a long time ago and has been recycling jackasses." - Anon |
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bngbuck
SFN Addict
USA
2437 Posts |
Posted - 02/28/2008 : 19:30:01 [Permalink]
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Chaloobi and Dr. Mabuse.....
| Except the orbit-to-earth beam may be affected by weather, depending on what frequency is used for the transmission. |
Some of your previous posts suggest familiarity with the principles of electrical power distribution. Is it your speculation (like Dave's) that some advanced form of UHF to GHF microwave generation and beam focused transmission to a rectenna area would be as, or more, practical to develop as the metallurgical molecular manipulation necessary to create a sufficiently conductive metal (or carbon composite) material to fabricate the enormously strong cable (tether) necessary to support the weight of it's several hundred miles of length?
I have read most of the wikilinks to these concepts, they all leave one with an impression of very early technological therorization of these kind of solar power projects, ending in the '90's.
Do you, or anyone, have any knowlege of recent serious work on long distance wireless power transmission or geosynchronous satellite-earth tethering with carbon nanotube power transmission cables?
These are indeed exciting engineering dreams that may actually be in the process of becoming reality. Strangely, I cannot find much current reference to progress in these fields! Military security?
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bngbuck
SFN Addict
USA
2437 Posts |
Posted - 02/28/2008 : 19:53:54 [Permalink]
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Dude.....
| Wind power, imo, should be our primary focus for electrical generation. There is enough to power us for a long long time, |
What are your thoughts on the power transmission problems (line losses) resulting from the long distances existing between wind-rich geographical areas, (largely the southwest and midwest plains areas); and the areas of largest demand and consumption; largely coastal population centers?
California is somewhat of an exception, because of population density; the extensive wind farms in the state are not far from demand areas. The huge developments underway in Texas will soon (a decade) exceed the entire state's demand and transmission technology will need to keep pace with generation capacity.
Battery or capacitor storage is, of course, one alternative solution, as in substation positioning along the trans-continental transmission routes. Mooner's interest in capacitors is not misplaced, this energy storage principle may be a very significant part of the answers to these problems!
Ah, the almost religious faith of the futurist! I have it, and it certainly seems to be more dependable than the equivilant theological expectation of hopeful prayer! |
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Dude
SFN Die Hard
USA
6891 Posts |
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Dude
SFN Die Hard
USA
6891 Posts |
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HalfMooner
Dingaling
Philippines
15831 Posts |
Posted - 02/29/2008 : 02:54:59 [Permalink]
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Here's a link to PZ Myers' post on how a couple of farmer's groups cut funding to University of Minnesota researchers after those researchers pointed out that biofuels would have a net negative impact on the environment.
On the research results, the farmers' spokesman said, "The university hurt the farmers' feelings, OK?"
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“Biology is just physics that has begun to smell bad.” —HalfMooner
Here's a link to Moonscape News, and one to its Archive. |
| Edited by - HalfMooner on 02/29/2008 02:58:28 |
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HalfMooner
Dingaling
Philippines
15831 Posts |
 Posted - 02/29/2008 : 03:09:28 [Permalink]
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Originally posted by bngbuck
Battery or capacitor storage is, of course, one alternative solution, as in substation positioning along the trans-continental transmission routes. Mooner's interest in capacitors is not misplaced, this energy storage principle may be a very significant part of the answers to these problems! |
Though I agree that supercapitors could help a great deal in the grid distribution system, my main concern is getting some kind of practical batter-or-battery-substitute into automobiles themselves, the goal being to produce a greener car that is every bit (or more) practical as existing ICE autos. Range, affordability, and quick recharge along the highway at at home are the keys to this practicality. I really feel this is the one key technology we are missing right now, and one that will probably soon have a solution.
All the generating and distribution problems are basically expansions in scale on the grid using existing (and emergent) technology, with added sources as they become available.
We could always build enough nuclear fission plants to cover any slow growth of alternative sources, when a much greater need for power on the grid kicks in with fully electric cars.
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“Biology is just physics that has begun to smell bad.” —HalfMooner
Here's a link to Moonscape News, and one to its Archive. |
| Edited by - HalfMooner on 02/29/2008 03:13:04 |
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chaloobi
SFN Regular
1620 Posts |
Posted - 02/29/2008 : 06:33:46 [Permalink]
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| Wow. That was really cool. |
-Chaloobi
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chaloobi
SFN Regular
1620 Posts |
Posted - 02/29/2008 : 06:35:10 [Permalink]
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Originally posted by Dave W.
Originally posted by chaloobi
However, they compete with food crops which will likely lead to deforestation to free up more crop land, which would be a net increase in carbon in the atmostphere and a reduction in biodiversity. Not good. |
Be careful, or you'll hurt the farmers' feelings.
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Woops. We'll fund your science so long as your studies conclude what we want them to. That's nice. |
-Chaloobi
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chaloobi
SFN Regular
1620 Posts |
Posted - 02/29/2008 : 06:57:43 [Permalink]
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Originally posted by bngbuck
Chaloobi and Dr. Mabuse.....
| Except the orbit-to-earth beam may be affected by weather, depending on what frequency is used for the transmission. |
Some of your previous posts suggest familiarity with the principles of electrical power distribution. Is it your speculation (like Dave's) that some advanced form of UHF to GHF microwave generation and beam focused transmission to a rectenna area would be as, or more, practical to develop as the metallurgical molecular manipulation necessary to create a sufficiently conductive metal (or carbon composite) material to fabricate the enormously strong cable (tether) necessary to support the weight of it's several hundred miles of length?
I have read most of the wikilinks to these concepts, they all leave one with an impression of very early technological therorization of these kind of solar power projects, ending in the '90's.
Do you, or anyone, have any knowlege of recent serious work on long distance wireless power transmission or geosynchronous satellite-earth tethering with carbon nanotube power transmission cables?
These are indeed exciting engineering dreams that may actually be in the process of becoming reality. Strangely, I cannot find much current reference to progress in these fields! Military security?
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I'd never considered using the Space Elevator concept as a power transmission line nor heard the suggestion before this thread. Every orbital power scenario I've read used microwave transmission. As far as the nuts and bolts details of that, I'm almost completely ignorant.
Regarding the space elevator, from what I've read the cable would have to be twice as far as geosynchronous orbit or counterweighted with an asteroid or something. So we're talking about 22k to 44k miles of cable. I'm not so sure this would be a great solution to the power transmission problem because of distribution issues from the base of the cable. One of the key enablers of orbital power, and the advantage the military is most interested in, is the ability to beam the power to any point on Earth.
Wiki's got a great article on the Space Elevator if you're interested. This would greatly further the goal of a true space industry, completely independant of orbital power.
Here's a solar power satellite article. Also, I posted a link earlier in the thread to the web site of the Pentagon study from 2007.
And here's one on wireless power transmission. |
-Chaloobi
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| Edited by - chaloobi on 02/29/2008 06:58:07 |
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Pelayo
Skeptic Friend
USA
70 Posts |
Posted - 02/29/2008 : 08:21:40 [Permalink]
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Dude, your links were about high altitude wind energy, I simply posted a story about the lack of wind causing a power shortage in Texas with conventional wind turbines. That should have reinforced the usefulness of high altitude turbines.
About solar-
Back in the 80s Tennessee Valley Authority was sibsidizing solar water heater installations. Everything was going just fine until budget problems forced cancellation of the subsidity. Within a few years, homeowners began dismantling the equipment becuase the systems were a maintenance mightmare and without the subsidy, the homeowners were never able to recoup the investment. Many homeowners were also not participating because they would be required to cut down some trees.
There may be new solar thechnology since the eighties, but a significant breakthrough will be needed before solar energy is viable in small installations on the eastern half of the US.
With oil over $100 per barrel, it is now becoming economically feasable to extract oil form shale. One of the firms I work part time for is preparing a bid to design a new plant out west.
High oil prices may stimulate research into new energy sources, but high prices also make other sources of fossil fuels more attractive. Win some - lose some.
Update: http://www.dailyreckoning.com/rpt/OilShale.html
This is the "Rocky Mountan News" some of the reporting may or may not be hype.
http://www.rockymountainnews.com/drmn/news_columnists/article/0,1299,DRMN_86_4051709,00.html
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I have a habit of posting without reading all previous comments, if I am repeating someone, well, excuse me, please.
"No tendency is quite so strong in human nature as the desire to lay down rules of conduct for other people." - William Howard Taft
"God ran out of new souls a long time ago and has been recycling jackasses." - Anon |
| Edited by - Pelayo on 02/29/2008 08:32:32 |
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chaloobi
SFN Regular
1620 Posts |
Posted - 02/29/2008 : 08:58:38 [Permalink]
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Unfortunately the now economical formerly marginal sources of oil don't do much to address the carbon foot print issue. Regarding solar, I've still not had time to look up the article on the new cheaper and more efficient solar cells... I believe solar water heaters don't use actual photovoltaic cells, however. I think the sun just heats the water directly.
EDIT:
About solar cell tech advances, by this article from last december's SciAm it's looking pretty optimistic:
Superefficient, Cost-Effective Solar Cell Breaks Conversion Records
A tiny chip similar to the solar cells carried by many satellites and other spacecraft today--including the surprisingly long-lived Mars Rovers--has shattered previous records for maximum efficiency in producing electricity from sunlight. "This is the photovoltaic equivalent of the four-minute mile," affirms Larry Kazmerski, director of the Department of Energy's National Center for Photovoltaics in Colorado. "This is a disruptive technology that eventually could provide us, at least in the Southwest, with cost-competitive electricity fairly quickly."
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The resulting efficiency nearly doubles that of standard silicon solar cells, which hover at 22 percent. That gain requires, however, the use of light-concentrating devices, such as miniature plastic lenses and mirrors. The new solar cell achieved 40.7 percent efficiency under such concentrated light at the testing center at the National Renewable Energy Laboratory in Colorado. One cell of just 0.26685 square centimeter (or roughly 0.04 square inch) pumped out 2.6 watts of electricity when bathed at the maximum light concentration. "Every five minutes the spectrum of the sun changes," Kazmerski explains. So tests are conducted "under a simulator where everything stays constant."
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And the triple-junction solar cell may not hold the efficiency record for long. "We are also looking at four-, five-, even six-junction solar cells," Lillington notes. "There are at least three or four different approaches to take the efficiency into the 45 percent range." And that means the price of energy harvested directly from the sun will continue to drop. |
Regarding the pollution from solar cell manufacture, again good news per Sciam:
Dark Side of Solar Cells Brightens
A life cycle analysis proves that solar cells are cleaner than conventional fossil fuel power generation
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But a new analysis finds that even accounting for all the energy and waste involved, PV power would cut air pollution—including the greenhouse gases that cause climate change—by nearly 90 percent if it replaced fossil fuels.
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Environmental engineer Vasilis Fthenakis, a senior scientist at Brookhaven National Laboratory in Upton, N.Y., and his colleagues examined the four most common types of PV cells: multicrystalline silicon, monocrystalline silicon, ribbon silicon and thin-film. (Other contenders, such as amorphous silicon or superefficient multijunction cells were excluded for lack of data or lack of widespread application to date.) Even taking into account the low efficiency of thin-film solar cells or the energy needed to purify silicon for the other types of PV, all proved to entail significantly fewer emissions in their entire life cycle than the fossil fuels needed to produce an equivalent amount of electricity.
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Even though thin-film solar PVs employ heavy metals such as cadmium recovered from mining slimes, the overall toxic emissions are "90 to 300 times lower than those from coal power plants," the researchers write in Environmental Science & Technology.
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And, as Fthenakis and colleagues argued in a recent article in Scientific American, if storage technologies such as compressed air improve, then PV could provide the majority of electricity needs in the U.S. "With storage," Fthenakis says, "it is feasible to go to 100 percent."
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-Chaloobi
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| Edited by - chaloobi on 02/29/2008 10:17:58 |
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Pelayo
Skeptic Friend
USA
70 Posts |
Posted - 02/29/2008 : 10:21:17 [Permalink]
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| These solar water heaters I wrote about used solar collectors for direct heat transfer to the water. |
I have a habit of posting without reading all previous comments, if I am repeating someone, well, excuse me, please.
"No tendency is quite so strong in human nature as the desire to lay down rules of conduct for other people." - William Howard Taft
"God ran out of new souls a long time ago and has been recycling jackasses." - Anon |
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JohnOAS
SFN Regular
Australia
800 Posts |
Posted - 03/01/2008 : 01:06:48 [Permalink]
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Originally posted by chaloobi
About solar cell tech advances, by this article from last december's SciAm it's looking pretty optimistic: |
Here's a link to the transcript and interview on the podcast from the same issue. From memory it was both interesting and informative, if still somewhat speculative. The whole podcast is usually about 25 minutes. The interview is probably 10-15.
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John's just this guy, you know. |
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Biofuels vs Solar
