Subject: Hearing on "Space Solar Power: A Fresh
Look" before the Subcommittee on Space and Aeronautics of the House Committee on Science, October 24, 1997.
Members Present: Chairman Rohrabacher (R-CA), Weldon (R-FL),
Bartlett (R-MD), Calvert (R-CA), Cook (R-UT), Cramer
(D-AL), Luther (D-MN), Lampson (D-TX)
Witnesses:
Opening Statements
Mr. John Mankins, Manager of Advanced
Concepts Studies, Office of Space Flight, NASA
Mr. Gregg M. Maryniak,
President, Sunsat Energy Council and Senior Scientist, Futron
Corporation
Dr. Jerry Grey, Director
of Aerospace and Science Policy, American Institute of Aeronautics
and Astronautics
Chairman Rohrabacher opened the hearing by stating
that space solar power (SSP) is "precisely what NASA as an
agency should be all about" - the development of opportunities
in space which are uncovered during NASA's missions. He stated
that NASA's lack of preparation to follow up on SSP, a concept
that, he claimed, "cries out for further research,"
may be because NASA wants to focus on human space flight, "in
hopes of reclaiming the glory days of Apollo." He feels that
SSP is just as exciting -- or even more so -- as sending an astronaut
to Mars, and is closer to NASA's mission. He cited the Next Generation
Internet project as an example where NASA funding is enabling
competition for the private sector, similar to what the SSP project
could be. He wants NASA to take the next measured step in research,
and believes that this visionary approach would reap huge public
support for NASA . The space station, he said, is a tremendous
engineering project with direct benefit to people on Earth; SSP
can provide great benefits as well. Ranking Minority Member Cramer
discussed the fact that SSP is not a new issue, but requires a
long term focus. SSP requires a radical reduction in cost of access
to space, which NASA is already investing in.
John Mankins was the first witness, and testified
about NASA's 1995-1996 Fresh Look study in which he had participated.
The conclusion of the study was that economic and technological
factors have changed significantly since SSP was first debated
in the 1970's and that it was time to conduct additional studies
with a long term view of 10-20 years for technological maturation
to make SSP possible. Gregg Maryniak testified that the Earth
will be populated with ten billion people in the next century,
with an exponential increase in energy requirements. He also discussed
SSP research being conducted by other countries, including Canada,
France, China, and Japan. The International Space Station could
also benefit from a solar power satellite energy source, which
would reduce the problem of drag by beaming power to station in
lieu of the need to have large solar panels, he stated. He believes
that it is NASA's role to improve technology and reduce risk of
commercial players, and therefore NASA should support SSP research.
The final witness, Dr. Jerry Grey, claimed that SSP is the most
important subject area for the general public, Congress, and DoE
because of its long-term view for life on Earth. He stated that
NASA's focus in the HEDS enterprise is on the exploration side,
and there is not consistent support for the equally important
developmental goals that can be achieved through the use of space
technologies, including SSP, advances in communications and Earth
remote sensing, commercial microgravity applications, the entertainment
industry and eventually perhaps space tourism. He believes that
in order to correct that imbalance, NASA's technology advancement
programs need to be coordinated by a single office whose responsibility
would be "planning for and, through technology advancement,
building the capability for both exploration and development of
space by humans." He states that "(b)ecause of its legislative
charter, as well as the unique capabilities the agency has developed
through the years, NASA is the only agency able to oversee the
advancement and development of many of the technologies Mr. Mankins
has identified in the Fresh Look study's risk-reduction technology
roadmap as being critical to space solar power system development."
Questions and Answers
Chairman Rohrabacher started the questioning by asking how much SSP would cost and who should pay. Mr. Mankins responded that preliminary studies showed that the first platform of the Sun Tower model would cost between $5-7B after the technology has been developed and would produce 400 megawatts of energy, enough to supply a small city. The Chairman then asked if SSP would have a detrimental impact on the environment, specifically the ozone layer. Gregg Maryniak answered that the Earth receives radio beams and microwaves every day. The energy density is what matters, and the center of SSP is less dense than sunlight. Space solar power is therefore possible, he stated, without detrimental effect. It could be used to help underdeveloped countries to industrialize while creating a new industry. Congressman Lampson asked about the 1980's Office of Technology Assessment report that cited economic obstacles to SSP. Mr. Mankins replied that it was the goal of the Fresh Look study to resolve those obstacles. The finding of the study was that costs have been drastically reduced since then; basic technologies have been developed. For example, at the time of the OTA report, the shuttle wasn't operating. The problem with space transportation, added Mr. Maryniak, is that there is not enough of it. Congressman Lampson then asked what NASA is doing in SSP now and what it needs to do. Mr. Mankins cited the Fresh Look study completed last year, and listed ongoing R&D programs under the Office of Space Flight and the Office of Space Science. Congressman Weldon's questions focused on industry's interest and support of SSP and the possibility of working with the satellite industry. Other questions focused on the amount of research and cost necessary to get SSP underway, and how much market interest and industry support there would be for SSP, considering that fossil fuels are a finite, pollution-causing resource. Congressman Bartlett asked about how much new technology would be needed; Mr. Mankins replied that 8-10 major areas of technology needed to be advanced technologically, although all were between an order of two and five improvement over current technology and would cost substantially below $10B for technology maturation. Mr. Bartlett explained that while he doesn't believe in "greenhouse gases" he'd be "willing to ride that horse" if that's what it would take to get funding for SSP. Chairman Rohrabacher stated that he had spoken recently with the Speaker and Joint Taxation Chairman Archer about a proposal to make manufacturing in space a tax free endeavor in order to raise private sector resources, and that they expressed interest. He wants to get NASA to focus on SSP as a long term project, rather than human travel to Mars. He asked if the witnesses had talked with anyone at NASA about this. Mr. Mankins testified that there have been a number of discussions, but at this time in the context of the real struggle to make the books work on the Balanced Budget Agreement, NASA is not making SSP a priority at this time. Mr. Maryniak stated that he had had conversations with the Administrator and believed that he personally was interested in SSP. Dr. Grey suggested that the Subcommittee discuss the possibility of using some of the overlap technology between what NASA is already engaged in, such as reduced cost of space transportation, and SSP technology requirements to begin an SSP program at NASA. Mr. Rohrabacher replied that Mission to Planet Earth might be a good place to put such a project. He said NASA may eventually get an astronaut on Mars, and he isn't against it, but that SSP should come first because of the benefit to mankind that could be derived from SSP. Mr. Lampson asked if anything could be accomplished now without additional funding. Mr. Mankins replied that there is technology work being conducted at NASA now that is applicable to SSP, including low cost of space transportation, which is the third goal of NASA's strategic plan. Mr. Lampson then asked if the electric companies could be expected to contribute funding to the project; Dr. Grey said that there is some support and that the interest level of the utilities would depend on the risk of the technology advancement, and that the reduction of this risk was a perfect role for the Federal government to fill. The Chairman closed the hearing by expressing his agreement with the other members that "this has been a fascinating hearing and I look forward to further discussion on the subject."
before the
Subcommittee on Space and Aeronautics
Committee on Science
House of Representatives
October 24, 1997
I am pleased to have the opportunity to speak with
you today concerning the topic of space solar power, and specifically,
the "Space Solar Power: A Fresh Look" study conducted
in 1995-1996, which I participated in.
As the Committee is aware, NASA is not the lead in the Federal Government for power systems technology development for Earth applications. Commercial space solar power is not currently a priority within NASA's current strategic plan. With limited budget resources envisioned for NASA under the Balanced Budget Agreement, funding for any focused NASA effort in support of space solar power technology is neither included in NASA's existing budget nor contemplated at this time for future NASA budgets.
“Solar power satellites” were invented by a Czech-American, Dr. Peter Glaser of Arthur D. Little, in 1968. Following several years of preliminary studies, and driven by the impetus of the oil crises of the time, a major study of power from space was conducted by the then newly-created Department of Energy, with the assistance of NASA.
During 1976-1980, the equivalent of about $50 million (in current dollars) was invested by DOE. Space solar power advocates believed that the nation would shortly pursue this new technology as it had fusion-based energy twenty years earlier and fission-based energy ten years before that.
Instead, the results of the 1970s study led to the stoppage of any serious consideration of space solar power in the U.S.
Why did this happen? The answer is primarily economic.
Using the technological approaches that were at hand in that era, the DOE-NASA study created a “1979 Reference System” design for solar power satellites which quickly became the focus of discussion and debate.
The 1979 Reference System involved placing a series of exceptionally large platforms in geostationary Earth orbit, each to deliver 5 Gigawatts via wireless power transmission using a microwave beam to a megacity in the U.S. (See Figure 1.) Sixty such satellites were projected, delivering a total of 300 Gigawatts capacity.
These systems were to be launched using extremely large, fully-reusable two-stage heavy lift launchers (see Figure 2) and assembled in space by hundreds of astronauts at equally large, dedicated space factories in Earth orbit (see Figure 3).
At the bottom line, the 1979 Reference System was projected to require more than $250B (in 1996 dollars) and at least 20 years to develop technology, build required infrastructure, and deploy the first operational system.
It was clear that no profitable business in any normal sense of the term could be created on this basis. As a consequence, no meaningful participation of private sector capital was expected in solar power satellite development and deployment. And a government program of this magnitude was judged unnecessary Ð if not outright ridiculous Ð in the absence of an impending threat to the nation.
Another reason work on power satellites stopped was the market focus.
The 1970s study focused on domestic U.S. energy demand alone. However, by 1980, public concerns caused by earlier oil crises were already fading fast.
Outside of a few important organizations – and the special topic of nuclear energy – there was little public concern at the time regarding energy supplies for markets outside the U.S. or related long-term environmental impacts.
A final reason is that there was excessive technological risk.
The scope of the enterprise, as it was conceived at the time, required the successful concurrent development of approximately 100 major new, extremely high-risk technologies that vastly surpassed the state-of-the-art of the day.
As a result of these factors – economics, markets, and technological risk (and others) – government work on space solar power essentially stopped in the U.S.
However, times and technologies have changed during the past 17 years. Moreover, some 25 years have passed since the invention of the system concept that later became the solar power satellite 1979 Reference System.
As a result, as a part of its advanced concepts program, during 1995-1997 NASA conducted a "Fresh Look" study of the possible commercial generation of space solar power for transmission to and use on the Earth.
The goal of this effort, which involved government, industry and universities, was to determine whether new concepts and technologies have emerged that might make space power technically and economically viable within the foreseeable future.
The fresh look study focused on the global energy market – including the U.S. Ð rather than only the U.S. domestic market.
The study determined that, to be economically viable any new space solar power system concepts must fall within a range in an “economic trade space” –costing about $1B-$10B to begin generating power commercially and producing power at a cost of no more than 1¢-10¢ per kilowatt-hour. (See Figure 4)
The team spent the better part of a year organizing and examining 29 diverse new and existing system and subsystem concepts. The study eventually developed a series of design strategies for future space solar power systems; these included:
Ultimately, the Fresh Look study team identified two new systems concepts, founded on these principles and using new technologies, that might make possible space solar power systems that are less expensive than the 1979 Reference System.
One of these, the “SunTower," is a middle Earth orbit constellation that could provide global energy services quickly (if albeit intermittently at first). This concept is modular, self-assembling, gravity-gradient stabilized and involves the use of many discrete solar array systems. With successful technology maturation, this system concept appears to be viable as soon as 10-20 years from now. (See Figure 5)
The second, the “SolarDisk," is a geostationary Earth orbit platform that would provide regional energy services almost continuously, but for a larger investment. This system is also modular, but is spin-stabilized and requires onboard robotic systems for assembly. Given technology maturation and the successful implementation of initial systems such as the SunTower, this system concept appears to be viable in the far term, no sooner than twenty years from now. (See Figure 6)
These concepts address the global energy market. This means that they would not have to begin by competing against well-established, fully-amortized ground power systems.
The concepts – and particularly the SunTower – are comprised of “brilliant” systems, largely self-assembling rather than requiring massive in-space infrastructures that are themselves manufactured, launched, and assembled in space at great cost.
By using many thousands of identical, mass-produced elements working together, rather than individual, giant systems constructed at factories in space dramatically lower initial hardware costs are expected. Just as is proving true today on the ground in terrestrial solar power and in space through the new large telecommunications satellite constellations, larger manufacturing runs lead to radically lower costs.
The concepts should be able to be launched in relatively small packages. Thus, they could make use of space transports that are “common” to other new space industries, such as public space travel and point-to-point fast package services.
Finally, these new space solar power concepts appear to be potentially applicable to diverse NASA and commercial space applications. For example, enabling very low-cost, large-scale solar electric propulsion for interplanetary transportation, or radically lower cost solar power for all commercial satellites.
Times and technologies have changed.
Changes have occurred in technology. And many of the most important advances needed to make power from space a reality are already underway.
For example, the Reusable Launch Vehicle program and the associated Advanced Space Transportation program have already started the U.S. down a path that should lead by early in the next century to commercial launch services at prices of $100s per pound rather than $1000s per pound of payload to low Earth orbit.
Also, low orbit Earth satellite constellations are setting a benchmark for modular, "brilliant," mass-produced space systems that points directly toward Fresh Look study concepts. Even new automobiles are far more “intelligent” than the subsystems that comprised the SPS Reference System of the 1970s.
This is not to suggest that the technologies that would be needed for space solar power are easy or already in hand. Aggressive research and development – perhaps over as long as a decade – would be required before a commercial project to deliver solar power from space could be undertaken.
However, new space solar power concepts require fewer systems and fewer technology developments than those entailed in the 1979 Reference System: the degree of technical risk appears far lower and more tractable.
Changes have occurred in the market.
The U.S. Department of Energy has projected that during the coming 25 years world population will grow by as much as 25% while the world demand for electricity will double. (See Figure 7.) Using current technologies, this increasing use of electricity will inevitably lead to similar increases in the release of “green-house gases” and escalating increases in the concentration of those gases in the atmosphere.
Moreover, a substantial number of scientists are concerned that this projected increase in greenhouse gases might in turn lead to global warning and possibly impact the Earth’s climate over the long term.
There appears to be a clear need to pursue technologies that can enable dramatic increases in renewable energy production worldwide Ð thus making possible continuing economic growth in the developing world.
Changes have occurred in the economics – along with the changing market –for prospective space power ventures.
Most importantly: space commerce has come of age. This year, commercial market space industry revenues exceeded government-funded industry revenues for the first time. Billions of dollars are now being raised regularly for new space ventures.
The global markets for energy are real. If the high-risk technologies needed to enable space power systems to be technically feasible are matured, then private sector capitalization of such ventures should be far more viable than could have been dreamed in 1980.
The results of the Fresh Look study suggest that it may be possible for a hypothetical space power venture – once the needed technologies have been matured – to begin generating power commercially in less than five years and for an initial investment approaching that of the larger telecommunications satellite ventures now being pursued.
The development of space solar power technology would require the concerted effort of many organizations. Within the U.S. government, the Departments of Energy, Defense, Commerce and Transportation, as well as NASA, would all have to be engaged in various roles.
Industry would have to participate from the very beginning – and not just aerospace companies, but also global energy companies, power plant builders and power utilities.
This would be a global venture from the start. For example, space solar power would involve the allocation of radio spectrum Ð and assuring non-interference of other (typically telecommunications) users of near-by spectrum. The establishment of standards, research and development partnerships and many other aspects would all require international cooperation and coordination.
Finally, environmental and health issues must be considered carefully.
No new power technology is risk free. Appropriate assessments would be needed to assure that the costs and risks of a space solar power option were lower than those of competing technologies (such as coal-burning plants or nuclear reactors).
Consideration must be given to both the launch of such large space systems as well as their operation. The safety ramifications of using a microwave beam for wireless power transmission to the Earth must be carefully researched and the results articulated in appropriate governmental, professional and public fora.
In closing, I would like to reiterate that the recently-completed Fresh Look study was preliminary. Additional studies are needed. If the commercially-viable space solar power system concepts are to be realized, aggressive R&D would also be required.
It was nevertheless the conclusion of the Fresh Look study that the time has come for a serious reconsideration of solar power from space as a potential global energy option for the 21st century.