Yesterday I met with a world-famous, economics-minded, globetrotting, space cynic. Naturally, this was at one of the D.C. area’s Irish pubs, which various Internet sources claim is my typical work location. Um…yea. The discussion was too good to keep to myself, so here are some takeaway points for your consideration and comment:
Archive for August, 2007
Posted by Coyote on August 24, 2007
Posted by Coyote on August 10, 2007
Regarding power beaming from satellites at GEO to the Earth’s surface:
“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. …
Posted by Coyote on August 10, 2007
One of the goals is to turn space solar power over to the commercial sector as soon as possible. This demands a business case that allows competitive pricing to the consumer for space-based solar power while creating sufficient profit motives for industry. One of our participants asked for the following:
“I want to ask for an separate and identified ongoing discussion of the business case on this web site. That section would need to include an evolving market and financial analysis models. It would be a kind of progress chart towards actually doing the deed.”
So here it is. Please take a look at the preceding thread regarding The Goal for 2050 and the Build Forward and use this to base your estimates.
Posted by Coyote on August 7, 2007
Enthusiasts and Skeptics,
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.
This must be done using a sound business case. John Mankins calculates that this can be achieved by keeping the costs of delivery and assembly on orbit below $3,500 per kilogram–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. Paul Werbos 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. Dennis Wingo and others have suggested that the first customers for space-based solar power will be international–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.
Posted in Commercial Challenges to Space-Based Solar Power, International Partnerships for Space-Based Solar Power, Logistical Challenges to Space-Based Solar Power, Scientific Challenges to Space-Based Solar Power | 52 Comments »
Posted by Coyote on August 5, 2007
The Russian News and Information Agency released a story by Yuri Zaitsev (click the link above to read). Therein he nicely summarizes the need for space solar power and the evolution of photovoltaic cells that collect and convert solar power into electricity. What is most interesting is that he asserts that by using pure quartzites (citing, “The largest deposits of very pure quartzites are found in Russia, which had vast reserves of them”) that:
Recently the Joint Institute for Nuclear Research in Dubna, near Moscow, developed a photo cell with an efficiency of almost 50%. Scientists describe their product as a “star battery.” It is an example of how nanotechnology can improve the workings of well-known processes.
Keep in mind that every improvement in efficiency along the collection-delivery pathway improves the business case.
This begs two questions:
1. What are the technical implications of ~50% efficient cells?
2. Does this signal cooperation or competition with the Russians?
Posted by Coyote on August 3, 2007
On Wednedsay, 1 Aug 2007, I was a guest on “The Space Show” with host Dr David Livingston. David was a superb host and the call-in questions were quite good. Part of the summary that David posted included the following:
“Col. Smith told us why the military is interested in SSP and this is something you need to hear Col. Smith explain. But as you will see, this is a national imperative. Listeners asked many questions about economics, time tables, antennas, frequencies, and more. Questions were asked about space tourism as a possible facilitator as well as ITAR issues.”
You can hear the show by clicking here: http://archived.thespaceshow.com/shows/747-BWB-2007-08-01.mp3
Feel free to comment or ask questions!
Posted by Coyote on August 1, 2007
Taking the long view, we don’t need to rush to answer every question immediately.
There are some wide open trade spaces that need to be examined and experimented with much more closely. Here are some examples:
Energy collection: What method is best; photovoltaic or solar dynamic collection? Within each method, there are various designs, for example, using the photovoltaic method, which technique of collection is best; large flat arrays or sun towers with concentrator mirrors?
Power beaming: What method should be used to broadcast to the ground; microwave or laser? Each has pros and cons. Microwave is certainly safer, but lasers require a relatively small receiver by comparison. Microwave might be best for permanently supplying a city with power, but laser might be better for broadcasting to a location that needs a rapid set-up time…such as part of a disaster relief effort.
What are the other major trade spaces???