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	<title>scientific-challenges-to-space-based-solar-power &amp;laquo; WordPress.com Tag Feed</title>
	<link>http://en.wordpress.com/tag/scientific-challenges-to-space-based-solar-power/</link>
	<description>Feed of posts on WordPress.com tagged "scientific-challenges-to-space-based-solar-power"</description>
	<pubDate>Tue, 21 May 2013 12:54:47 +0000</pubDate>

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<title><![CDATA[Discovery Channel to Show Documentary on Space-Based Solar Power!]]></title>
<link>http://spacesolarpower.wordpress.com/2008/09/03/futures-channel-does-documentary-on-space-based-solar-power/</link>
<pubDate>Wed, 03 Sep 2008 22:53:15 +0000</pubDate>
<dc:creator>Coyote</dc:creator>
<guid>http://spacesolarpower.wordpress.com/2008/09/03/futures-channel-does-documentary-on-space-based-solar-power/</guid>
<description><![CDATA[I told Mike &#8220;Green Hornet&#8221; Hornitschek that we&#8217;d be famous! The Discovery Channel]]></description>
<content:encoded><![CDATA[<p>I told Mike &#8220;Green Hornet&#8221; Hornitschek that we&#8217;d be famous!</p>
<p>The <a href="http://dsc.discovery.com/">Discovery Channel</a> (which my kids LOVE and we LOVE them watching it!) will show a documentary on Space-Based Solar Power at 10pm on 12 September, 2008.  We filmed it in Washington DC at the <a href="http://www.space-frontier.org/">Space Frontier Foundation&#8217;s</a> <a href="http://www.space-frontier.org/Events/NewSpace2008/">New$pace 2008 conference</a> (you are a <a href="http://www.space-frontier.org/joinus.html">member,</a> aren&#8217;t you?).  It was so totally cool working with the pros from the Futures Channel who did the filming (they must work closely with the Discovery Channel).  It was amazing watching them do their thing.  They turned a small conference room at the hotel into a studio, wired us up, created mood lighting, and all that Hollywood stuff.  These guys were entirely professional and WOW, it was entirely motivational being around professional media people who want to tell a story so kids get excited!</p>
<p>So, here is the preview from our most excellent friends at the Futures Channel:</p>
<p><a href="http://www.thefutureschannel.com/dockets/realworld/space_based_solar_power/">Space-Based Solar Power on the Futures Channel</a></p>
<p>Make sure you tune-in to the Discovery Channel when it airs.  Record it, and share it with all your friends, consistent with the laws in your viewing area*!</p>
<p>Cheers!</p>
<p>Coyote</p>
<p>* We&#8217;ve got to be careful with copyright laws&#8230;I once got into a kerfuffel because I described a baseball game to a friend of mine without the expressed written permission of the commissioner of major league baseball!</p>
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<title><![CDATA[Wireless Power Broadcast for Computers and Phones Anticipated!]]></title>
<link>http://spacesolarpower.wordpress.com/2008/08/23/wireless-power-beaming-for-computers-and-phones-anticipated/</link>
<pubDate>Sat, 23 Aug 2008 13:01:23 +0000</pubDate>
<dc:creator>Coyote</dc:creator>
<guid>http://spacesolarpower.wordpress.com/2008/08/23/wireless-power-beaming-for-computers-and-phones-anticipated/</guid>
<description><![CDATA[Power beaming is a critical for space-based solar power. It also would be nice if our laptops and ce]]></description>
<content:encoded><![CDATA[<p>Power beaming is a critical for space-based solar power.  It also would be nice if our laptops and cell phones didn&#8217;t need to be plugged in, becoming truly wireless.</p>
<p>Intel recently brought the concept closer to reality with a live demo illuminating a 60 watt bulb on stage at an annual meeting in San Francisco of the company&#8217;s developers.  Their goal is simple, free computers and other devices from power cords.</p>
<p><!--more-->The event was reported by staff writers on <a href="http://www.spacemart.com/">Spacemart.com</a> in an article titled, &#8220;<a href="http://www.spacemart.com/reports/Intel_cuts_electric_cords_with_wireless_power_system_999.html">Intel Cuts Electric Cords With Wireless Power System</a>.&#8221;</p>
<p>I think if people used wireless power broadcast systems in their own homes, the concept of power beaming from space wouldn&#8217;t seem so strange or even dangerous.  Perhaps we need to give a push to this idea?</p>
<p>Cheers!</p>
<p>Coyote</p>
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<title><![CDATA[Space Solar Power Demo: WWWWW &amp; H?]]></title>
<link>http://spacesolarpower.wordpress.com/2008/01/12/space-solar-power-demo-wwwww-h/</link>
<pubDate>Sat, 12 Jan 2008 19:01:55 +0000</pubDate>
<dc:creator>Coyote</dc:creator>
<guid>http://spacesolarpower.wordpress.com/2008/01/12/space-solar-power-demo-wwwww-h/</guid>
<description><![CDATA[It&#8217;s time to get busy again! Our very good friend, Hu Davis, recently circulated some good que]]></description>
<content:encoded><![CDATA[<p>It&#8217;s time to get busy again!</p>
<p>Our very good friend, <b>Hu Davis</b>, recently circulated some good questions regarding the who, what, when, where, why, and hows of demonstrating space solar power.  He poses the questions from the perspectives of two groups; space solar power enthusiasts, and some NASA people who work the International Space Station (ISS).   (Please note that like the rest of us, our friends at NASA-ISS are just brainstorming with us to see what help the ISS might be able to lend to advance space solar power concepts&#8211;there is no official NASA position or policy on any of this yet.)</p>
<p><!--more-->Below you will find the questions posed by Hu.   Please comment!</p>
<p>From the SBPS crowd:</p>
<p>1. What should be the content, scope and cost of an updated systems study to re-examine the cost effectiveness of a full scale network of 5 to 10 GWe satellites and their necessary space and ground systems?  There are many subordinate questions not yet answered, including how to pay for it and who should run it.</p>
<p>2.  What should be early, low cost (&#60; $100 Millions total) demonstrations?  By whom?  When?  Source of funds?</p>
<p>3.  What should be demonstrated at higher cost, but costing much less (10-20% of that of a full scale prototype)?  Sequence? Timing?  Cost?   Whose money?</p>
<p>4.  How should we address the &#8220;space infra-structure&#8221; matter?  When?  Who? In what order?  Time and costs?</p>
<p>5.  What will the full scale prototype be?  When can it become operational?  Schedule?  Cost?  Barriers?</p>
<p>From the ISS bunch:</p>
<p>1.  What can the ISS support?  Power / time?  Suspended mass?  Torques? Dimensions of test articles?  Pointing?  RMS usage?  EVA?  Expected end date of availability?  We need an &#8220;ISS User&#8217;s Guide&#8221; for space power development.</p>
<p>Thanks! Coyote</p>
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<title><![CDATA[Space-Based Solar Power Interim Assessment (Release 0.1) is Published!]]></title>
<link>http://spacesolarpower.wordpress.com/2007/10/10/sbsp-interim-assessment-release-01-is-published/</link>
<pubDate>Wed, 10 Oct 2007 13:00:06 +0000</pubDate>
<dc:creator>Coyote</dc:creator>
<guid>http://spacesolarpower.wordpress.com/2007/10/10/sbsp-interim-assessment-release-01-is-published/</guid>
<description><![CDATA[Hello Everyone! Click here for the &#8220;Interim Assessment!&#8221; From the Foreword of the report]]></description>
<content:encoded><![CDATA[<p>Hello Everyone!</p>
<p>Click here for the  &#8220;<a href="http://spacesolarpower.files.wordpress.com/2007/11/final-sbsp-interim-assessment-release-01.pdf" title="Interim Assessment">Interim Assessment</a>!&#8221;</p>
<p><!--more-->From the Foreword of the report itself:</p>
<p>Preventing resource conflicts in the face of increasing global populations and demands in the 21st century is a high priority for the Department of Defense. All solution options to these challenges should be explored, including opportunities from space.</p>
<p>In March 2007, the National Security Space Office’s Advanced Concepts Office presented the idea of space‐based solar power (SBSP) as a potential grand opportunity to address not only energy security, but environmental, economic, intellectual, and space security as well. First proposed in the late 1960’s, the concept was last explored in the NASA’s 1997 “Fresh Look” Study. In the decade since this last study, advances in technology and new challenges to security have warranted a current exploration of the strategic implications of SBSP. For these reasons, my office sponsored a no‐cost Phase 0 Architecture Feasibility Study of SBSP during the Spring and Summer of 2007.</p>
<p>Unlike traditional contracted architecture studies, the attached report was compiled through an innovative and collaborative approach that relied heavily upon voluntary internet discussions by more than 170 academic, scientific, technical, legal, and business experts around the world. I applaud the high quality of work accomplished by the team leaders and all participants who contributed in the last six months. I encourage them to continue their work in earnest as they move beyond this interim report and seek to answer the question of whether SBSP can be developed and deployed within the first half of this century to provide affordable, clean, safe, reliable, sustainable and expandable energy for mankind.</p>
<p>This interim assessment contains significant initial findings and recommendations that should provide pause and consideration for national and international policy makers, business leaders, and citizens alike. It appears that technological challenges are closing rapidly and the business case for creating SBSP is improving with each passing year. Still absent, however, is an appropriate catalyst to stimulate the various interested parties toward actually developing a SBSP capability. I encourage all to read this report and consider the opportunities that SBSP presents as part of a national and international debate for action on how best to preserve security for all.</p>
<p>//signed 9 Oct 07//<br />
JOSEPH D. ROUGE, SES<br />
Acting Director, National Security Space Office</p>
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<title><![CDATA[Technical Discussion On Power Beaming: Engineers Take Note!]]></title>
<link>http://spacesolarpower.wordpress.com/2007/08/10/technical-discussion-on-power-beaming-engineers-take-note/</link>
<pubDate>Fri, 10 Aug 2007 19:22:02 +0000</pubDate>
<dc:creator>Coyote</dc:creator>
<guid>http://spacesolarpower.wordpress.com/2007/08/10/technical-discussion-on-power-beaming-engineers-take-note/</guid>
<description><![CDATA[Regarding power beaming from satellites at GEO to the Earth&#8217;s surface: &#8220;The atmosphere h]]></description>
<content:encoded><![CDATA[<p>Regarding power beaming from satellites at GEO to the Earth&#8217;s surface:</p>
<p>&#8220;The atmosphere has two bandwidth width windows though which it is possible to beam power between space and the surface efficiently, and outside of which atmospheric absorption will kill you: (1) a microwave window, of which the 2.45 GHz frequency (~ 12 centimeter wavelength) employed in the 1970s DoD/NASA reference SPS design is typical, and (2) a visible window extending perhaps as far into the near infrared as a micron of so in wavelength.   &#8230;</p>
<p><!--more-->The microwave window allows radio astronomers to see galaxies with their large antennae at the Earth&#8217;s surface; the second allows us to see the stars with our eyeballs. However, the wavelengths of these windows differ by a factor of 100,000, with profound implications for sizing of power beamers for space solar power applications.  A major consequence of the beam spreading by diffraction related to that employed by Arthur Smith below &#8212; that is, the factor X = (transmitter aperture)x(receiver aperture)/(wavelength)(distance) must be of order one for the transmission efficiency to be of order one or greater because only then  will the receiver aperture be big enough to capture the beam main lobe &#8212; is that kilometer or greater sized transmitting and receiving apertures are needed for microwave beamers to capture the main fraction of transmitted power from geostationary orbit (GEO) &#8212; the best location at least near term of a solar power satellite.</p>
<p>The diffraction limit on electromegnetic waves is a fundamental law of physics built into the structure of this universe. It can&#8217;t be beaten by clever engineering, and not for lack of trying (sparce arrays, etc.) The DoE/NASA reference SPS design of the 70s wound up with a 1 kilometer phased array transmitter and 10 x 13 kilometer rectenna. With these dimensions, and in order to attain a reasonable intensities inside the main lobe of the beam, you need a gigawatt sized SSP; with 5 x 10 kilometer solar panel arrays: ten gigawatts for Peter Glaser&#8217;s DoE/NASA reference design; perhaps as little as one GW for John Mankins&#8217; Fresh Look Study cleverly designed technology. But still big. Meaning big capital investment prior to first power.  In all fairness, fusion with its different physics scaling laws, also drives you for different reasons to large machines, like the 12 billion dollar International Experimental Thermonuclear Reactor (ITER) tokamak under construction in the South of France. This project isn&#8217;t even designed to produce net electric power. What it aims at is a sustained plasma burn from hot alpha particles, a &#8220;scientific milestone&#8221; far short of actual power output.  Size matters, and even though it&#8217;s an interesting and relevant question why the huge ITER has its $12 billion R &#38; D program, while SSP, intended for the same job of base load electricity production, has no money. The large size and capital investment to first power of both systems has to impact the business case. Ironically, it may be just because fusion is seen as a dream in the uncertain future, while SSP appears much more technologically mature that funding is so hard to get.</p>
<p><font color="#000000"><u>In the general soup of contemporary alternate energy discussions, diode laser beamers in geostationary orbit are a total game-changer for demonstrating space based solar power experimentally.</u></font> We can build and test them now. Can we beam electricity into Iraq even as the insurgency blows up power lines? Can&#8217;t say now how much it might cost, but it&#8217;s certainly feasible in principle. My predilections are to demonstrate beaming power to some poor African village, winning the hearts and minds of our brothers and sisters in the developing world, as opposed to blasting them to bits, as some will certainly accuse developers of laser power beaming of. But the thing about any new technology is that you really can&#8217;t say at the outset where exactly it will go. What we can say with some assurance that no one has a clue how to build a small, cheap fusion reactor that would work. But we can almost certainly build an SSP with laser beaming now that would work; and build it small enough to fit into a single launch vehicle payload at a small fraction of the cost of ITER, or for that matter of FutureGen (DoE&#8217;s proposed coal-gasification to electricity and hydrogen pilot plant with CO2 sequestered), or one of DoE&#8217;s new design Gen IV fission reactors on the drawing boards. So I want to strongly agree with Jordin Kare&#8217;s comments on a the viability of an laser SSP demo expressed in his E-Mail below.</p>
<p>Indeed, we, my son Eric &#38; I, have taken this idea further to the point of developing a 3-page report for DARPA: <a href="http://spacesolarpower.files.wordpress.com/2007/08/darpa-ssp-demo-exec-su_f2391.doc" title="darpa-ssp-demo-exec-su_f2391.doc">darpa-ssp-demo-exec-su_f2391.doc</a>). But at least so far, we haven&#8217;t got very far. Perhaps it hasn&#8217;t been seen by the right people, or hasn&#8217;t become visible at the right historical moment. So I throw it into the ring once more as part of this discussion on the business case for SBSP. (We space power guys may not have any money, but we have the most acronyms: SPS, SSP and now SBSP).</p>
<p>Your comments, of course, are most welcome.</p>
<p>Cheers,</p>
<p>Marty Hoffert<br />
Professor Emeritus of Physics<br />
Andre and Bella Meyer Hall of Physics<br />
Room 525, Mail Code 1026<br />
4 Washington Place<br />
New York University<br />
New York, NY 10003-6621 &#8220;</p>
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<title><![CDATA[The Goal for 2050 and the Build Forward]]></title>
<link>http://spacesolarpower.wordpress.com/2007/08/07/the-goal-for-2050/</link>
<pubDate>Tue, 07 Aug 2007 21:20:06 +0000</pubDate>
<dc:creator>Coyote</dc:creator>
<guid>http://spacesolarpower.wordpress.com/2007/08/07/the-goal-for-2050/</guid>
<description><![CDATA[Enthusiasts and Skeptics, To give you a basis for analysis, by 2050 the goal is to have forty or so]]></description>
<content:encoded><![CDATA[<p>Enthusiasts and Skeptics,</p>
<p>To give you a basis for analysis, by 2050 the goal is to have forty or so concentrator-photovoltaic space-based solar power (SBSP) satellites in geostationary orbit, each broadcasting via microwave between 2-5 gigawatts of power to terrestrial electrical power grids, with 1-to-5 broadcast antennas that can beam power to as many locations.</p>
<p>This must be done using a sound business case. <a href="http://www.spacefuture.com/cgi/glossary.cgi?gl=who&#38;term=John%20C%20Mankins">John Mankins </a>calculates that this can be achieved by keeping the costs of delivery and assembly on orbit below $3,500 per kilogram&#8211;keeping the cost to customers below $0.10 per kilowatt/hour. This will drive robotic assembly and tug systems to pull these enormous structures from low orbits to geostationary. On orbit fueling stations will be required. <a href="http://www.werbos.com/">Paul Werbos </a>believes the best way to do this is to get launch costs down below $200 per kilogram.  But several other factors help make the business case. For example, if the price of other energy sources goes up it helps to close the business case for SBSP. Other factors include the efficiencies associated with solar collectors, energy conversion, antennas/rectennas, signal path loss, etc. <a href="http://www.hobbyspace.com/AAdmin/archive/Interviews/Business/DennisWingo.html">Dennis Wingo </a>and others have suggested that the first customers for space-based solar power will be international&#8211;in areas such as India and Japan where the price per kilowatt/hour is astronomical compared to the Americas or Europe. All of this goes into making the business case.</p>
<p><!--more-->There will also be times when space-based solar power becomes <em>priceless</em>. When the Tsunami crushed the Pacific rim, when Hurricane Katrina flattened America&#8217;s Gulf Coast, and when United Nations forces responded to the beleaguered Darfur region the value of simply broadcasting power immeidately to the relief efforts would have been <em>priceless</em> in assisting the salvation of countless lives and facilitated the more immediate recovery of these disaster torn regions.</p>
<p>Keep in mind American and Allied forces operating inside Iraq. Convoying petroleum through the streets of Iraqi cities is a large source of casualties&#8230;and the electrical power plants that convert that petroleum into electricity are under frequent attack&#8230;and the lights go out&#8230;and the people aren&#8217;t happy. As I&#8217;ve mentioned before, one of our defense analysts calculated that the U.S. is paying between $300-to-$800 per gallon for fuel delivered to the Iraqi electric plants. Mike Hornetschek reports that 70% of all logistics movements inside Iraq is petroleum.</p>
<p>Inside Iraq, at this very moment&#8211;where people are dying&#8211;a supply of space-based solar power would have that <em>priceless</em> quality. And this is true wherever military forces and others are engaged not only in combat, but in nation building, humanitarian relief, disaster response, etc, etc, etc.</p>
<p>The question was posed to me today, &#8220;What does the military need.&#8221; Here goes:</p>
<p>According to <a href="http://spacesolarpower.files.wordpress.com/2007/06/sbsp-an-opportunity-for-strategic-security.ppt">Mike Hornitschek</a>, a military base inside the United States consumes approximately 10 megawatts of electrical power. Forward military base overseas are consuming approximately 5 megaWatts of electrical power.</p>
<p>I need space-based solar power satellites of the 5 megawatt class. Let&#8217;s say by 2015. This capability will transform our logistics and reduce our vulnerabilities. The development of this class of space-based solar power satellite is designed to deliver that <em>priceless</em> quality of energy. Best of all, it can be done with current technology using current spacelift vehicles. Think about that.</p>
<p>But most important of all, developing the 5 megawatt class of satellite gets the ball rolling towards the 2050 vision that started this discussion. We WILL learn a great deal and we WILL find new efficiencies. We may make huge adjustments in the <a href="http://spacesolarpower.wordpress.com/2007/08/01/trade-spaces/">trade spaces as detailed in a previous discusion</a>, and must be prepared to do so. In pressing ahead to field a 5 megawatt system, we will also be building the space industrial base and developing the rquisite spacefaring infrastructure to make the business case for the 2050 vision all the more viable.</p>
<p>There will likely be cities or regional utilities that will want to buy their own 5 megawatt satellite (or larger) as a backup, which will help the business case even more and give us a better look at problems that lie waiting for us as we build bigger systems.</p>
<p>The goal, then, for 2020 would be building/fielding a 10 megawatt system&#8230;1 gigawatt sytem by 2030&#8230;2-5 gigawatt system by 2040&#8230;on the way to fielding 40 2-5 gigawatt systems by 2050 as described above.</p>
<p>All the while the drive must be towards commercializing this effort at the earliest possible time. Energy must move at the speed and price established by free markets, not by government bureaucracy. To that end, I am working with <a href="http://www.nesdis.noaa.gov/space/about/morris.html">Ed Morris </a>and <a href="http://www.nesdis.noaa.gov/space/about/beavin.html">Mike Beavin </a>at the <a href="http://www.nesdis.noaa.gov/space/">Department of Commerce-Office of Space Commericalization </a>to make this happen.</p>
<p>Your thoughts???</p>
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<title><![CDATA[A Skeptical Engineer Has His Say...]]></title>
<link>http://spacesolarpower.wordpress.com/2007/06/24/a-skeptical-engineer-has-his-say/</link>
<pubDate>Sun, 24 Jun 2007 19:09:44 +0000</pubDate>
<dc:creator>Coyote</dc:creator>
<guid>http://spacesolarpower.wordpress.com/2007/06/24/a-skeptical-engineer-has-his-say/</guid>
<description><![CDATA[Click here to view briefing:  A Skeptical Analysis A very good friend of mine who is a respected eng]]></description>
<content:encoded><![CDATA[<p>Click here to view briefing:  <a href="http://spacesolarpower.files.wordpress.com/2007/06/skeptical-assessment.ppt">A Skeptical Analysis</a></p>
<p>A very good friend of mine who is a respected engineer constantly reminds me of how formidable a task space-based solar power really is. He quite literally thinks it is a ludicrous idea. He provided me with his first order assessment of the proposition to provide 100% of current US base load energy from space given today&#8217;s industry and infrastructure. It is filled with statements like:</p>
<blockquote><p><em>&#8220;At 100% efficiency and effective array thickness of 0.001 m (1 mm) mass on-orbit would be down by factor of ten – so it would only take ~ 1000 years to deploy at one EELV Heavy launch a day&#8221;</em></p></blockquote>
<p><!--more-->That doesn&#8217;t do it for me. Personally, I&#8217;d be delighted if space-based solar power could produce say, 10% of the US energy requirement by 2050, as part of a comprehensive clean energy program that includes, wind, ground-based solar power, nuclear, hydrogen, bio fuels, and other things we haven&#8217;t imagined yet. Moreover, I&#8217;d like to think that we will no longer be stuck with hugely expensive expendable rockets like EELV, and proper conservation initiatives will actually decrease our overall energy requirements by then.</p>
<p>Take a look at the briefing linked above. Give some thought, and share your comments.</p>
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<title><![CDATA[Scientific Challenges]]></title>
<link>http://spacesolarpower.wordpress.com/2007/06/09/scientific-challenges/</link>
<pubDate>Sat, 09 Jun 2007 23:44:13 +0000</pubDate>
<dc:creator>Coyote</dc:creator>
<guid>http://spacesolarpower.wordpress.com/2007/06/09/scientific-challenges/</guid>
<description><![CDATA[All, Many credible scientists and engineers tell us that we have concluded all of the science we nee]]></description>
<content:encoded><![CDATA[<p>All,</p>
<p>Many credible scientists and engineers tell us that we have concluded all of the science we need to make space-based solar power work. It is now just a matter of advancing the technology and logistics to make it economically feasible. Is this right?</p>
<p>Coyote</p>
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