An Interview with Dr. Feng Hsu

In this latest installment of our on-going series of interviews with some of the leading thinkers and scientists on the subject of energy, we interview Dr. Feng Hsu.

Perhaps the single greatest solution for eliminating the global dependency on fossil fuels is Space Solar Power.  This has not received nearly the coverage it should in the ever growing discussion about global warming and alternative energy.  This interview with Dr. Hsu is a great introduction to SSP, and from one of the greatest authorities on the subject.  Please plan to set aside some time to read this entire interview and you will learn about what might well be the solution to the global energy crisis.


Dr. Feng Hsu is Senior Aerospace Engineer for NASA and a former research fellow of Nuclear Energy Dept. (now Energy Sciences Technology) at BNL (Brookhaven National Laboratory, Dr. Hsu is a renowned world expert with decades of experiences in the field of Risk and Safety assessment and mission assurance management for complex engineering systems, such as nuclear power plant systems, space launch vehicle systems, solid rocket booster & interplanetary exploration spacecrafts as well as air or ground traffic control systems for civil aviation. Hsu was a key member of the Columbia investigation team at JSC, and he is now a leading NASA expert working on risk management for frontier space missions at NASA GSFC.  He has published over 100 articles and technical reports and has an extensive list of professional and academic honors, which include co-author of a recent paper bag by Apogee Books “Beyond Earth – The Future of Humans in Space” (; Members of Technical Committees on IEEE SMC, IEEE Systems Engineering, PSAM9; Members of ANS, AIAA, SRA; Sr. Advisory to ATWG (Aerospace Technology Working Group,; Leadership Council – The SEDA Institute; Sr. Advisory Board of the Engineering Panel – the Life Boat Foundation (, and Advisory board member of the Space Development Steering Committee etc.

Dr. Hsu is regarded as one of the foremost authorities and advocates for Space Solar Power (SSP), and for Solar energy to replace fossil fuels in general.  Solar Energy or SSP has not been widely discussed in the loud and growing conversation about global warming, yet it is starting to be viewed by many scientists as one of the most promising and feasible ways to completely replace dependence on fossil fuels.  Please take the time to read Dr. Hsu’s thoughts on solar energy and SSP issues and you may well agree with me that it could be the single best chance we have for a global renewable energy future.  Dr. Hsu, thank you for taking the time to be interviewed for the readers of Your title is Senior Aerospace Engineer and Risk Manager for NASA; what are your responsibilities and what does your job entail?


Hsu:  Yes, I am a senior staff engineer, manager and leading expert on technical and technology risk assessment and management from NASA GSFC. My major responsibilities are leading the center effort on technical risk assessment and management to ensure safety and mission successes of various NASA projects and programs at Goddard. Prior to joining NASA, I have done many years of engineering research in the nuclear energy field at Brookhaven National Laboratory, Dept. of Nuclear Energy. As many of you might know that over the years of witnessing the human struggle on nuclear issues and the ever worsening energy crisis, my main interest now has been gradually shifted from nuclear energy to solar energy and its related technology issues, especially on terrestrial or space-based solar power (SBSP); a profound basic concept and gigantic engineering endeavor which may truly bringing us the ultimate energy solution for all of humanity. Before coming to NASA GSFC working on major space programs such as JWST, HST and CxP (Constellation Program) etc, I also spent many years on the Space Shuttle Program at Johnson Space Center in Houston, where I led the effort on risk modeling of the extremely complex Space Shuttle systems, and was part of the Columbia Accident Investigation team there at JSC. I believe that through advocating solar energy and SBSP, my passion, my energy and expertise can be dedicated effectively on help bringing about the economic viability; technological and commercial realisms to the current president’s vision for space exploration (VSE). At the Foundation for the future energy conference your presentation was one of the few that took a look back at energy use throughout human history. Could you give a brief summary as to the stages we have passed through and how long they lasted?

 Hsu:  It is imperative for us to understand and always learn from the history of human civilizations, especially during crisis such as the one concerning energy and sustainability. In other words, there are no better lessons and more clear mirrors to foresee what lay ahead than looking at the foot tracks of our ancestors. To go quickly over the history of human energy consumptions and their related energy technology heritages, we can see that there have been fundamentally three eras of energy supply and consumptions in our human history. Not even a thousand years ago, throughout the long history of hundreds of thousand years of human presence on this planet, ever since the first fire was lit by mankind, our lives were based on wood-generated energy, basically based on the burning of firewood, tree branches and the remains of crops from agricultural harvests. Starting about 1600, we found coal and entered into the 2nd era of energy uses, namely the fossil-based energy supplies. Only a few hundred years later, about middle 1800 we incidentally discovered petroleum and commercialized the use of oil and gas, which brought about the entire modern industrial civilization of mankind. In the late days of first half of the 20th century, came the dawn of the Techno-era of energy use and production, as was propelled rapidly by the electricity generation of various technological energy forms, such as represented by hydro-power and the atomic energy generations. As the world demand of energy continues to soar, we’re now running into a profound energy crisis and other environmental crisis induced by our way of energy production, which is still predominately remained in the fossil-based 2nd era of human energy solutions.  As we can see since about year 2000 on, there is great uncertainty for the world energy supply, whether or not we engage in sustainable energy R&D, it’s up to us. The fossil fuel age on the scale of human history, if you plot the energy demand by year of human civilization on a terawatt scale, you will see a huge bump barely a hundred years ago. Before that, in the Stone Age, basically the cultivation of fire was the early human primitive creativity that led to the emergence of agriculture, cooking, tool-making, and all the early stages of human civilization. After about 150 years of burning fossil fuels, the Earth’s 3 billion years’ store of solar energy has been plundered. Therefore, in my view mankind must now embark the next era of energy supply and consumptions, namely to harnessing and rediscovering the mighty energy resource of our Sun, through extensive technology innovations. This era of taming solar energy through technology breakthroughs may well trigger the next giant leap of our civilization and elevating our species to transforming our combustion world economy into the forever sustainable Solar-electric world economy! I can never say enough of the paramount importance of solving humanity’s energy problems through learning from our ancestors – taming the nature forces of the Sun, much like mankind first harnessed the wild fire. We must allow common sense; logics and sound technologies drive our economy and drive the future of humanity. By the way, we should remember that even though the human discovery about fossil fuels could reach back before the start of recorded history, it did not became significant in our way of life until the dawn of the industrial revolution in the 19th century due to the lack of technology and engineering achievement. The Romans used flaming oil containers to destroy the Saracen fleet in 670. In the same century, the Japanese were digging wells to depth approaching 900 feet with picks and shovels in search of oil, and by 1100, the Chinese had reached depths of more than 3000 feet in searching of energy. This all happened centuries before the West had sunk its first commercial well in 1859 in Titusville, Pennsylvania. Now it’s time for mankind to heads up and starts digging into the sky, much like our ancestors dug into the surface of the earth long ago, but pursuing it with a fundamentally opposite and renewed yet brighter direction! We may not achieve what we would like to see (a solar-electric civilization) anytime soon, but we must start it now and staying on the right track – Harnessing the Sun! The evidence of global warming you presented was alarming. Please comment on the urgency of the situation and the timelines we are looking at to turn things around, if in fact that can be done? 

Hsu:  The place I work for now is Goddard Space Flight Center, which is a primer NASA (or world) research center in the forefront for space and earth science research, and for monitoring and analyzing any cosmic or global climate changes. So, I do get the first hand scientific information and data relating to global warming issues, especially on the latest of ice cap melting dynamics or changes in both poles of our planet. Also, I always get a chance to discuss closely with some of my Goddard friends, who are world leading experts on the subject.  I have no doubt that there is a clear trend of global temperature rise, and that the global warming is a pretty serious problem confronting all of humanity. Regardless of what may be the true or direct causes, whether it is due to human interferences or due to the cosmic cycling of our solar system dynamics, there are two basic facts which are crystal clear to all of us: (a) there have been overwhelming scientific evidence which showing clear and positive correlations between the level of CO2 concentrations in the earth’s atmosphere with respect to the historical fluctuations of global temperature changes; (b) Overwhelming majority of the world’s scientific community have consensus about the risks of a potential catastrophic global climate change if we humans will do nothing and continue to ignore this problem and continue the dumping of huge quantity of greenhouse gases into earth’s biosphere environment.   In my views as a risk assessment expert, or in the views from a probabilistic perspective, it is at least orders of magnitude more risky for humans to do nothing to curb our fossil-based energy addictions as compared to engaging in the fundamental shift of our energy supply landscape. This is because the risks of a catastrophic climate change can be potentially the extinction of human species, a risk consequence simply too high for us to do nothing about it. In my mind, it is absurd to hear some of the argument made by some of our politicians that humans should not worry about “global warming” because if we do restrict the burning of fossil energies, there will be economic consequences. Well, whoever makes such kind of argument is clearly ignorant of the concept of risk, uncertainty and risk mitigations. We are talking about options and choose between risks, as every human activities involving risk taking and we can not avoid risks but only to choose between them, making trade-offs and choose wisely. Therefore, there has to be a risk-based probabilistic thought process when comes to pick national or international policies in dealing with global warming or energy issues. As the measure of Risk is a product of Likelihood and Consequence, I believe the choice is crystal clear to most of us, when consequence or risk of a potential human extinction (due to catastrophic climate change) is to be compared with the potential consequence or risk of loss of jobs or slowing down the growth of economy (due to restriction of fossil-based energy consumptions). My view is that by making paradigm shift of the world’s energy supply through extensive R&D and technology innovations on renewable energy productions, we may well create countless new jobs and then end up triggering the next spectrum of economic development and industrial revolutions.  I will say that the acceleration and aggravation of a potential catastrophic global climate change is the number one risk issue of our current Combustion World Economy. I showed three pairs of pictures at the international energy conference back in April in Seattle where there were overwhelm evidence of glaciers disappearing at alarming rate ( is less important to assert any timelines of fixing or reversing the global warming trend, and so as the uncertainties of whether or not it can be done by any human interventions. It is up to the nature’s blessing depending on the magnitude of damages already done to the earth’s biospheres, and of course depends on the policies and effectiveness of the countermeasures we humans put in place as well. What is most imperative for all of us is whether we still continue the endless debate on the issue of global warming, or we would rather put our acts together and start to do something in a significant way! We have no other choices as it is a make or break it situation. You are a firm believer that the solar energy in general is the best renewable energy source for the future. Please explain why you think it is the best source for humanity? 

Hsu:  There is now an energy crossroad facing mankind. My thought is that we have, basically, two directions to follow: either we look for energy based on cosmic-based, open, and unlimited original resources, which means everything comes from the stars, from the Sun, or we follow the direction on Earth-based, local and confined secondary energy resources. There is no secret that every single bit of energy on this planet comes from the Sun. We have a small window of opportunity that exists, in my view, from 2000 on for maybe the next couple of decades. Either we’re going to go down or we’re going to go up as a species largely depends upon how we approaching our energy solutions in a very basic and fundamental way.  There is no doubt in my mind that harnessing the Sun is the next giant leap for mankind. Harnessing the Sun is like our ancestors first harnessed the wild fire: an inevitable and logical leapfrog in the process of human evolution. I would like to quote from Dr. Bill Michael from the University of Chicago: “Use of fire illustrates that human evolution is a gradual process; modern humans did not emerge overnight in a ‘big bang’ of development, but rather slowly adapted from their primitive origins. The use of fire by humans throughout time to overcome environmental forces is a fundamental and defining aspect of human nature.”  Before reaching the tipping point of the global sustainability, it’s time for humans to tame the natural forces of the Sun and harness it for the well-being and survival of our species. The best place, of course, for a nuclear fusion reactor is about 149E6 km (149 x 106 km) away. It’s free of charge. The Sun’s energy only takes 8 minutes to arrive and leaves no radioactive waste, and it’s terrorist proof. Our Sun puts out about 3.8E11 TWh of energy per hour. Our planet receives about 174,000 terawatt each second. Every hour, Earth’s surface gets more solar power than humans use in the whole year. Humans should learn to bypass the solar-to-fossil inefficiency. About 4.6 billion years ago, the Earth was just formed, and it was 3.5 billion years ago that there was the first sign of life. Not until 1.5 billion years ago was there multicell biology; real life started just about 500 million years ago. The dinosaur lived about 150 million years ago and went extinct. Human beings have lived maybe a few hundred thousand years. You can see that it took about 3.5 billion years and rare geologic events to sequester hydrocarbons and build up hydrogen in the atmosphere. If you do a little calculation, you will find that using direct solar energy is about 1,200,000,000,000 times more efficient than using the secondary solar energy - oil. Why not go direct to the Sun? Please compare solar energy to the other forms of renewable energy currently be discussed. Pros and cons please? 

Hsu:  We must set priorities and choose wisely. The projected world energy use by fuel type is that in the next 30 years, we’re going to have almost explosive increase in demand. In global energy consumption, mankind must revolutionize the world energy landscape. According to US DOE data ( that the renewable energies include biomass, hydropower, geothermal, wind, solar, and other – all of those came up to about 6 percent of total energy production here in the US. However, on the fossil side, nonrenewable energies consist of about 94 percent. To recognize that solar energy is the best option for the future, we have to first set in priority of our energy requirements, and understand how should we evaluate and compare our energy options for major R&D activities for the future of mankind? This seems to be a major challenge for us. We need to define major criteria. It has to be quantifiable. In my view, it has to be affordable for all human beings at low cost. It has to be inexhaustible in terms of the livable planetary lifetime. It has to cause no harm to the environment, ecosystem, or human lives. And it must be easily available and accessible around the globe. It has to be in usable, flexible, and decentralized scalable energy forms, and there must be low risk of potential misuse for mass destruction. When we set key requirements, they have to be achievable. The energy option has to satisfy the need and goals of humanity. It has to help retain and improve human values and global collaborations. It must be highly achievable through demonstrated human creativity. It must help expand human presence and survival within our solar system. And it has to be consistent in elevating human culture, quality of life, and civilization. When you carefully compare and evaluate each available option of the renewable energy sources against these requirements and criteria, it is not hard to understand that the solar power in general will be the most viable sources of renewable energy for sustainable human development into the future. Now if we are comparing some of the key energy options based on the major requirements and criteria as stated above, we can see that major nonrenewable energy sources, such as fossil fuels (oil/gas) will be depleted in another 40 to 60 years. Coal will be depleted in about 500 years. Some people estimate a thousand years, but that doesn’t really matter. Before you deplete all the coal, your global environment already has caused catastrophic change. The mining of nuclear fission material will deplete in about 50 years as well. All fossil fuels are harmful to Earth’s biosphere, and nuclear power has major issues with waste deposit, and the risks of proliferation and misuses are high. Nuclear, after all, had 40 years’ chance already, and it didn’t help the world solve the energy problem. Major renewable energy sources: hydro power – limited and unstable water resources; liquid biomass – competes for land with food production. You have heard that in Mexico tortilla prices have gone up about 60 percent in two years. Hydrogen (fuel cell) has high risk for storage and transportation. Wind/geothermal/tidal is intermittent, unstable, and costly. Nuclear fusion has been brought up and studied by government funds for over half a century and it is unlikely to achieve anytime soon to curb the acute deterioration of our environment, and it has a high risk for harm. I believe that something that offers tremendous or explosive energy can be misused for ill-minded human destructive purposes. The US has been so busy and spent so much money trying to prevent just a handful of small nations from building their won nuclear reactors. Just imagine the risk scenario that if the know-how for making the A-bombs some 200 years down the road will be as easy as the terrorists in Iraq knowing how to make the IEDs nowadays? On the other hand, solar energy, basically as a general case – doesn’t matter if it is surface or space-based – is achievable, has no limit, and there’s no harm to human beings. are also a strong advocate of solar energy from space, and believing that Space Solar Power has great potential for the future. Please explain what it is, and why solar energy from space?  

;Hsu: Why solar energy from space? Good question David. One of the major challenges of terrestrial solar power is that, we have less than one percent of the world’s energy coming from solar power due to high photovoltaic (PV) cell costs and its inefficiency of converting the Sun light energy into electricity. Based on the existing solar technology and its PV materials, it would require a field of solar panels the size of the state of Vermont to power the whole US electricity needs. And to satisfy world consumption requires about one percent of the land that is used for agriculture worldwide unless there are breakthroughs made in conversion efficiency of PV cells and lower the cost of producing them and producing affordable batteries in a significant way.  There is roughly about 7 to 20 times less energy per square meter on Earth than in space, depending on the geological locations. One of the major concepts of energy from space is so called SSP, which stands for Space Solar Power. SSP as a space-based energy system concept isn't a new idea at all. The concept has been systematically explored and studied since the middle 1970s. Actually, Nikola Tesla's great dream was to find the means to broadcast electrical power without wires in between. Early in the first half of the 20th century, when Tesla, the pioneer of modern electromagnetism and inventor of wireless communication had addressed the American Institute of Electrical Engineers about his attempts to demonstrate long-distance wireless power transmission over the surface of the Earth. Tesla said, "Throughout space there is energy. If static, then our hopes are in vain; if kinetic – and this we know it is for certain – then it is a mere question of time when men will succeed in attaching their machinery to the very wheel work of nature." The SSP concept and much of its present form was originated in 1968, when Dr. Peter Glaser first brought out the idea of SSP as a source for continues power generation for the Earth's future energy needs. Glaser's basic idea was that satellites in geosynchronous orbit would collect energy from the Sun. The energy would be converted to radio waves and beamed to a receiving site on the ground. The ground antenna would then reconvert the radio waves to electricity for power consumption. In a typical SSP system, solar energy is collected in space by a satellite in a geostationary orbit. The solar energy is then converted to direct current by solar cells, and the direct current is in turn used to power microwave generators in the gigahertz frequency range. The generators feed a highly directive satellite-borne antenna, which beams the energy to the Earth. On the ground, a rectifying antenna (rectenna) converts the microwave energy from the satellite to direct current, which, after suitable processing, is fed to the terrestrial power grid. A typical SPS (Solar Power Satellite) unit – with a solar panel area of about 10 square km, a transmitting antenna of about 2 km in diameter, and a rectenna about 4 km in diameter may yield an electric power of about 1 GW (equivalent of a large scale nuclear power station). Two critical aspects that have motivated research into SPS systems are the lack of attenuation of the solar flux by the Earth’s atmosphere and the twenty-four-hour availability of the energy, except around midnight during the equinox periods. Is SSP a viable energy option in terms of cost and technological possibility? What are the key challenges involved to develop SSP? 

Hsu:  Among the key technologies involved in the SSP are microwave generation and transmission techniques, wave propagation, antennas, and measurement and calibration techniques. These radio science issues cover a broad range of aspects involved in an SSP system, ranging from the technical aspects of microwave power generation and transmission to the effects on humans and the potential interference with communications, remote sensing, and radio-astronomy observations.  Is SSP a viable option? Well, in my opinion yes, it can be a viable energy option for base-load electricity generation to power the needs of our future. This is because SSP satisfies every key major criteria of a viable energy option except the cost based on current space launch and propulsion technology. We all know that cost (or space transportation cost) is a major issue for SSP. That is why to overcome the high launch cost; the development of autonomous robotic technology for on-orbit assembly of large solar structures along with the needed system safety and reliability assurance technologies for excessively large and complex orbital structures are among the major technical challenges for SSP. Nevertheless, there are no breakthrough technologies that need to be invented nor of any theoretical obstacles need to be overcome for a SSP project to be carried out.  Our society has seriously overlooked the great potentials of SSP as opposed to other energy concepts, and has owed a great deal for adequate funding in support of any SSP related R&Ds. The US government funded a total about 20 million dollars on SSP study back in the late 1970s in the height of the early oil crisis, and then practically abandoned this project with nearly zero dollars spent up to the present day. Above all, a government funded SSP demonstration project is absolutely long overdue. Mr. Ralph Nansen, a friend of mine, who was the former project manager of the Apollo program at Boeing and later managed the DOE-NASA funded SSP proof of concept study in the late 1970s, gave a great detail of the Boeing study effort in his excellent book “SUN Power”. I highly recommend the reading of Ralph’s book for those who interested on this topic. Also, Dr. Peter Glaser’s book is another superb reading on this topic as well. (; What I really like to point out here is that we can solve the cost issue and making SSP a commercially viable energy option through human creativity and innovations in both technological and economic fronts. Yes, the current launch cost is prohibitive to SSP however, besides continuing quest for low cost RLV (reusable launch vehicle) technologies, there are other revenues of utilizing ingénues commercial or business models to overcome the SSP cost issues. One such great model has been studied and is now being pursued rigorously by an American private aerospace entrepreneurial company, the SIG (Space Island Group) based in California. The SIG idea is to modify and utilizing the Space Shuttle heritages by turning the huge volumes of the external tank into commercial asset for the space-based research and orbital tourism industry. ( A huge demand in space tourism will certainly bring about the high launch rate, and it will in turn drive down the space transportation cost therefore help making SSP more viable. The key is for mankind to start pursuing energy in the right direction. Take for example, the case of the commercial aviation industry, who would thought that ordinary people could afford air travel just several decades after Wright brothers had succeeded in their first aircraft test fly?  On the other hand, we should pursue SSP through advocating solar energy as a fundamental energy strategy for the future of humanity. Unlike some of the views from our colleagues in the space community, I believe that we should not, nor need to restrict our vision on choosing between terrestrial solar and SSP. In fact, the dream of SSP can be realized much sooner through advocating the use of terrestrial solar energy and the pertinent R&Ds on a grand globe scale. This is because the advancement in major terrestrial solar technology, such as the nano-particle based ultra high efficiency and low weight, low cost PV cells along with the super capacity and low cost energy storages will also lead to affordable SSP development. Our ultimate goal is to taming the “very wheelworks of nature” and harnessing the Sun, so it’s not important as how we would achieve this goal, whether it’s via SSP or through terrestrial solar approaches. With the rapid advancement of nanotech based PV solar cell materials that is now reaching over 50% efficiency while can be cheaply produced (along with revolutionary battery technologies), it is totally possible that one day we don’t have to launch huge PV structures (SPS) into LEO to satisfy the base-load electricity consumptions for the entire planet, except of course for power supply in space environment. It’s extremely exciting to see in recent years, the kind of rapid advances and accomplishments made in the PV cells research filed, and an over 30% annual growth of the solar energy industry even without government policy support of such major nations like US and Russia. Imagine what will be our dependence on oil if every house in the future is to be built with cheap and highly efficient solar cell materials for the roofs and sidings, and every shaded parking lot in shopping malls and office buildings is to be built and equipped with solar powered charging plugs for electric cars?! This sounds like a perfect undertaking for the emerging private, entrepreneurial space businesses springing up around the world. Could these entities help, or should this be solely the work of governments?  

Hsu:  Yes, I believe that the realistic hope of a commercially viable SSP system truly lies in the collaborative effort from the emerging private, entrepreneurial space businesses and venture capital investment within the world community, just like what you said. Quite frankly, I am very disappointed, yet pessimistic about the government involvement in this great human engineering and technological endeavor, especially on the part of the much needed support from the US government. I am also disappointed, even surprised to see there was no mention about energy and economic development from the current president’s Vision for Space Exploration (VSE). On the contrary, I am happy to see there are great visionaries in the world who do see the significance and inner connections of future energy prospect to the vision for space exploration.  One such visionary is the recently retired president of India, Dr. Kalam Abdul. Dr. Abdul had the great vision and courage to speak publicly on the SSP prospect while addressing the Symposium on "The Future of Space Exploration" organized by Boston University lately. Kalam believes the space research is truly inter-disciplinary and has enabled true innovations at the intersection of multiple areas of science and engineering. More profoundly, the President said: “civilization will run out of fossil fuels in this Century. However, solar energy is clean and inexhaustible. However solar flux on earth is available for just 6-8 hours every day whereas incident radiation on space solar power station would be 24 hrs every day. What better vision can there be for the future of space exploration, than participating in a global mission for perennial supply of renewable energy from space”? He asked.


Nevertheless, the government support on policies and financial resources for R&D and the related technology demonstrations are crucial to the success of such giant effort. As we all know that since the 1980s, any organized activity to study or develop SSP or solar power satellites (SPS) has been limited. There was no US government sponsored work until NASA initiated their “A Fresh Look” Studies in the mid 1990's. Subsequently the Department of Energy abstained from any involvement. However, during this time the Japanese government and industry became interested in the concept. The Japanese updated the reference system design developed in the System Definition Studies in the late 1970's, conducted some limited testing and proposed a low orbit 10 megawatt demonstration satellite. Their effort has been curtailed by their economic problems and by their lack of manned space capability. SSP Interest by other nations has persisted however, but only at low levels of activity.


The overwhelming initial cost of development and deployment has remained the primary obstacle. Number one on the list of cost barriers is again the cost of space transportation. Solar power satellites are only economically feasible if there is low cost space transportation. Therefore, in order for SSP to be successful, we need an organized consortium consisting of private businesses, venture capitalists from major international partners, along with government support of major industrial nations on R&D and technology demonstrations. We need this to bring down associated project and technology risks on safety, reliability and technology maturity. The Comsat model for the successful launching and commercialization of communications satellite industry should be a viable approach for SSP as well. Sounds like we need a global “Manhattan Project”. Should the United States take the lead and other nations will join later, or should there be a multi-governmental organization put in place first. Can the US do this alone?

Hsu:  Yes, a “Manhattan Project” like major effort led by the US with participations from broad international community is what needed to a successful creation, implementation and operations of a commercial scale SSP system. Please remember, an inherent feature of solar power satellites is their location in earth orbit outside the borders of any individual nation with their energy delivered back to the earth by way of certain form of WPT (wireless power transmission). The applications of WPT must be compatible with other uses of the radio frequency spectrum in the affected orbital space. The SPS infrastructure must also be launched and delivered into space. Therefore, it is vital for international and government involvement to coordinate global treaties and agreements, such as covering frequency assignments, satellite locations, space traffic control and many other features of space operations that are mandatory in order to prevent international confrontations.

I believe it is imperative for a multi-governmental organization or entity be put in place first for a major SSP project, and it will be extremely difficult, if not inconceivable, for the US or any single nation to do this alone at any useful or significant power scale due to the many political and technological reasons as stated. However, it is equally important that there must be a leading nation to provide the necessary leadership in such complex and interdependent international SSP effort. In a partnership of multiple governments and industries, it is vital that the leadership and responsibilities of the various project elements be clearly defined in order to prevent chaos. There should be some logical parameters to outline how this can be done. The key step is to establish a lead nation. The United States is the logical leader in this area because of the breadth of technology infrastructure and capability that already exists, as well as the magnitude of financial resources available in its industry and financial community.In any case, space solar power is going to be a gigantic yet achievable human technology and engineering endeavor, based on heritages of human ingenuity. We can go to the Moon; we can achieve splitting atoms; we can also overcome the inefficacy problems of the solar-electric conversion, and we can achieve the goal for affordable access to space and hence making the SSP a cost competitive energy production for all of humanity. Key SSP component technologies will also enable human economic expansion and settlement into space, which is utterly important for the permanent survival of our species. To this end, such a “vertical expansion of humanity” into our solar system in the new millennium can be every bit as important (if not far more critical) as the “horizontal expansion” achieved by our ancestors since the 1400s.  Indeed, SSP will provide an ideal platform for promoting human collaborations that will help reduce the global economy imbalances. It can be also a major steppingstone for humanity’s next giant leap for harnessing the Sun and transforming the combustion world economy into the solar-electric human civilization that is likely to transpire and elevating our species. Is there anything else you would like to say to the readers of 

Hsu:   Again, I can never say enough about the vital importance for mankind to start looking at the Sun for all answers to our ever increasing energy needs, and to solve our environmental or societal crisis! I call the “harnessing of the Sun” as the 3rd giant leap in the process of human evolution. The first giant leap was when human beings got down from the trees and started to use Fire, which brought tool-making, agriculture and ancient civilization. Then we invented machinery and discovered electricity, which allowed us the 2nd giant leap forward and brought up modern industrialization. Now we’re running into profound energy and environmental crisis. Mankind, from the primitive use of fire to the use of randomly discovered fossil fuels to the intelligent and creative use of sustainable energy sources, we must now embark the next giant leap of our civilization, that is to Harness the Sun, and therefore allowing transformation and elevation of a combustion civilization (built upon primitive and secondary energy sources) to the forever sustainable Solar-electric civilization (will build on inexhaustible and direct energy source from the stars)! Can mankind achieve the third giant leap into the solar-electric civilization? My answer is positively YES! Humans have been capable of profound achievements as huge as the Manhattan and Apollo projects. We can certainly succeed in taming the mighty power of our star, whether it’s terrestrial solar or space-based solar energy, humans must achieve our next leap forward. Together we can make it happen – but not if we fail to educate and mobilize the politicians and decision-makers around the globe. People always argue: “Solar energy or SSP are too costly; we cannot do it.” The real challenge for mankind for solar energy as well as SSP is really a “Manhattan project for peace.” The political system has been a key barrier for either SSP or any massive scale terrestrial solar energy installations to be developed by mankind largely due to fossil and nuclear energy establishments and due to our existing economic infrastructures. Mankind already got ourselves into the civilization based on non-sustainable energy sources; it’s not easy to change. However, in my view the key changes needed are much less technical or economic ones than that of the social and political ones. Indeed, it’s a policy issue, not quite a technology or economic issue. As in the case of space race or war, it’s easy and we can achieve nearly anything, but to do something gigantic for peace for all of humanity, it’s not so easy. It’s not in our human nature. But Dr. Robert Goddard liked to say: “It is difficult to say what is impossible, for the dream of yesterday is the hope of today and the reality of tomorrow.” I would like to conclude this interview with what I said at the end of my talk in the Seattle energy conference: “as intelligent creatures rooted in the cosmic origin, humanity was meant to survive and spread its presence all over the universe by milking the energy of the stars!”.  Thank you! 

Hsu: Thank you David, for the interview opportunity.