Satellite solar power: Renewed interest in an age of climate change?

The concept of generating electricity using satellite solar power (SSP) has recently enjoyed renewed interest as a source of non-fossil fuel energy. First proposed in the 1960s, then studied sporadically in the past decade, SSP offers a potentially large supply of power but without the carbon emissions associated with evidence of global climate change. SSP faces challenges: competition from other non-fossil renewable energy, such as wind power, and the lead-time and costs required to assemble, test, and deploy an SSP system. At the request of a consortium of electric utilities, of NASA, and of the US National Science Foundation, this paper estimates the value of SSP in four distinct geographic regions, each differing in terms of their resource base for conventional renewable energy. Because deployment of SSP would be sometime in the future, we explicitly incorporate uncertainty in the model. We find the cost-effectiveness of SSP is highly sensitive to geographic region, to the reliability of SSP, and to the cost of carbon damages avoided by its use. The results offer guidance for decision makers in space, energy, and environment programs who must allocate scarce budgetary resources among competing public investment alternatives for clean energy.     

Safety issues in SPS wireless power transmission

The use of wireless power transmission in Space Solar Power (SSP) activities creates significant policy issues regarding the beam right-of-way. There will not be a single beam, there may well be hundreds of beams for economical systems. Are some or all of these power beams to be afforded priorities of space for unobstructed power delivery, or must the beaming systems be designed to be capable of detecting any and all potential beam interceptions and appropriately responding? The repeated interruptions for guaranteed safety of transit for freely moving air and space traffic are of great consequence. The safety issues are critical, but the implications for equipment transient protection, energy storage system costs and the quality of power delivery service are also significant for wireless power transmission economics. A scenario of precursor wireless power transmission developments leading up to and including SSP applications will be used to frame and to discuss the beamed power technology implications and policy issues.     

European response to the NASA space station initiative

This article contrasts the political motivations behind the US space station initiative with those underlying the European Space Agency's Long Term Plan. Philip Chandler concludes that European cooperation in NASA's space station programme (SSP) will serve three needs: to buy time; to allow European users to undertake longer, manned experiments; and, to keep the Spacelab teams intact. However, in itself the SSP holds little value for Europe.     

Sandwich module prototype progress for space solar power

Space solar power (SSP) has been broadly defined as the collection of solar energy in space and its wireless transmission for use on earth. This approach potentially gives the benefit of provision of baseload power while avoiding the losses due to the day/night cycle and tropospheric effects that are associated with terrestrial solar power. Proponents have contended that the implementation of such systems could offer energy security, environmental, and technological advantages to those who would undertake their development. Among recent implementations commonly proposed for SSP, the modular symmetrical concentrator (MSC) and other modular concepts have received considerable attention. Each employs an array of modules for performing conversion of concentrated sunlight into microwaves or laser beams for transmission to earth. While prototypes of such modules have been designed and developed previously by several groups, none have been subjected to the challenging conditions inherent to the space environment and the possible solar concentration levels in which an array of modules might be required to operate. The research described herein details our team's efforts in the development of photovoltaic arrays, power electronics, microwave conversion electronics, and antennas for microwave-based “sandwich” module prototypes. The implementation status and testing results of the prototypes are reviewed.     

Will China become a military space superpower?

China's ambitious space program was born in extremely poor national conditions in 1956. By 15 October 2003, with the successful return of the Shenzhou-4 manned space flight, it had developed dramatically. While this flight is a milestone in China's space capabilities, the Shenzhou-4 mission should be considered not as an end, but as the entry ticket to the space power club of the USA and Russia. China may now be a space power, but it is not yet a military space superpower in the way of the latter two countries. This paper investigates whether China will become a military space superpower by reviewing the development of its space program. It examines Chinese military space capabilities in terms of their military space potential, and discusses the political, military and economic implications of this issue. Finally, the paper suggests that China should continue to take the road to openness, focusing on commercial and economic efforts. This will be an alternative direction in which the country can consider exactly what space capabilities it needs in order to continue its economic development.     

Power from space: the policy challenge

The scientific community has long embraced the concept of globalized collaboration, recognizing that scientific inquiry knows no borders and that scientific theory transcends nationality. With respect to translating scientific and technological innovation into practical application, however, national, political, and ideological barriers suddenly arise. At a time when the worlds of economics and finance are rapidly globalizing, the world of applied science lags behind — despite increasingly urgent need for global energy solutions. In the context of considering space solar power (SSP) systems, the author contends that these solutions require new ways of determining costs and benefits; that scientific experts should seek active engagement in the policy arena; and that SSP's scientific community has a critical role to play in advocating for consideration of space-based energy solutions.     

Organizing and managing satellite solar power

Building an organization and management structure to create, launch, utilize and protect a satellite solar power energy system will require a global policy for the beneficial use of SSP. The fundamental organizational tasks are: (1) R&D, achieved through a project organization characterized by the integrated management of applied science, development research and construction engineering; (2) investment, generated by a series of groups creating financial vehicles for public and private investment; (3) transmission and distribution, characterized by attention to an engineering and maintenance process emphasizing high reliability; and (4) crisis response, demanding readiness for instant response to potential internal or external scenarios. A differentiated global organization spanning the long timeframe of SSP will need to have a central management core representative of all parts of the organization, with the capacity for self-renewal and re-adaptation. To be successful over its long timeframe, the SSP organization will need to build continuity and public confidence through intergenerational communication, public education, and community outreach. Integrating structures must be created at all levels of the organization, and should encompass joint work tasks and information-sharing among both industrial and government members. Developmental and alliance partners who support the formation and financing of a differentiated satellite solar power organization will share commensurately in the technologies and competencies that are created.     

Russia's place in space: a home view

This paper analyses Russia's view of its involvement in international space cooperation and the Western concerns associated with this. In the current economic and political situation the Russian administration and space industry are eager to take part in all kinds of international space activity, which is seen as an opportunity to sustain the country's scientific and technological potential. Russia claims a fair share in both commercial space operations and joint space development programmes, appropriate to its capabilities as the world's number two space power. Western concerns about Russian interference in its policy and the problems involved in dealing with Russia should be solvable and are less dangerous than reverting to a situation of confrontation.     

Meeting the needs of the new millennium: passenger space travel and world economic growth

Without doubt, humans’ most urgent need at the start of the new millennium is the continuation of economic growth, which is the only means by which the great majority of the world population can lift themselves out of the poverty in which they live. A sine qua non for continuing economic growth is for the rich countries to continue to develop new industries—as they did throughout the 20th century, thereby creating high-productivity employment for hundreds of millions of people around the world. Arguably the most significant of these thus far is the development of passenger air travel from zero in 1900 to 1.5 billion passengers per year by 2000. It is becoming clear that passenger space travel could grow to reach a similar economic scale—and that no other space activity has comparable potential. The paper describes the potential contribution to world economic growth of passenger space travel; the failure of government space agencies either to aid its development or to make a contribution to economic growth commensurate to their cost; and the value for economic policy of prioritising the realisation of passenger space travel. The faster passenger space travel services grow, the more the space industry will contribute to “Meeting the Needs of the New Millennium”.     

Can power from space compete?

This report summarizes the findings of a report entitled Can Power from Space Compete? produced for NASA by Resources for the Future (RFF). In considering how well satellite solar power (SSP) is likely to compete in the market for electricity from the present to 2020, it finds that neither perceived shortages of fossil fuel nor climate change factors are likely to be major issues in this time frame. Moreover, the high costs of SSP and possible concerns over public health and national security will continue to constrain its development. This does not mean, however, that R&D into the subject should cease; it may well have a future in the short term when applied to non-terrestrial systems. The full report is available at http://www.rff.org.     

The PCA Rules for dispute settlement in outer space: A significant step forward

Outer space activities have evolved significantly. While they were previously the exclusive domain of a restricted number of states, now thanks to technological advances and the easing of governmental restrictions, space activities are carried out on a much larger scale and involve subjects of both a governmental and non-governmental nature. Furthermore, the commercial uses of outer space are making space business increasingly profitable and attractive to potential investors. As the economic value of outer space activities, as well as the number of space actors grows, it is nearly inevitable that international disputes related to the use of outer space will occur. Until recently, international space law contained little dedicated machinery to settle international outer space-related disputes. This absence significantly weakened the applicability and enforceability of space law and contributed to a climate of uncertainty. In order to address these issues, the Permanent Court of Arbitration (PCA) adopted the Optional Rules for Arbitration of Disputes Relating to Outer Space Activities on 6 December 2011. The PCA Space Rules represent a significant development in the field of space law because they provide a voluntary and binding dispute settlement method accessible to all space actors and modeled on the specific legal and economic characteristics of space activities. This paper describes the genesis of the PCA Space Rules, assesses their content and innovative character, evaluates their possible implications for the settlement of outer space disputes, and argues that they should be positively received by the outer space community.     

Bayesian framework for assessing the value of scientific space systems: Value of information approach with application to earth science spacecraft

Space systems play an important role in today's society by generating or transmitting information from source to sink(s). The acquisition of the space system is often justified by the type, quantity and quality of information provided or transmitted. This work posits that the value of a class of space systems derives from and can be assessed through the value of information these systems provide. To this effect, a Bayesian framework is developed to assess system value in which systems are viewed as information sources, and stakeholders as information recipients. Information has value to stakeholders as it helps to update their beliefs, enabling them to make decisions that can yield higher expected pay-offs than in the absence of information. This increase in expected pay-offs is ascribed to the value of the system. Based on this idea, a new metric, Value-of-Design (VOD), is introduced to quantify the value of a class of space systems with unpriced services. The Bayesian framework assesses the Value-of-Design for the space system by considering the impact of the information transmitted on the actions taken by stakeholders, and estimating the resulting pay-offs from these actions. The framework here developed is then applied to the case of an Earth Science satellite that provides hurricane information to oil rig operators in the Gulf of Mexico. Probability models of stakeholders’ beliefs, and economic models of pay-offs are developed and integrated with a spacecraft design tool. Results from the application point to clusters of payload instruments that yielded higher information value, and minimum information thresholds below which it is difficult to justify the acquisition of the system. Additionally, the system is analyzed in Cost-VOD trade space to provide program managers with additional insights into the coupling of a system's predicted value generation and its associated lifecycle cost.     

A socio-economic evaluation of the lunar environment and resources: II. Energy for the selenosphere

This first of several study papers, based on a fundamental paper presented in 1972, provides an independent conceptual analysis and evaluation of the lunar environment as industrial base and habitat. A selenosphere system strategy is outlined. The underlying concept is that of one or several lunar industrial zones for resource extraction and on-surface processing, integrated with a circumlunar zero-g processing capability, serving markets in geolunar space. A classification of lunar elements by utilization category is presented. Lunar oxygen is a prime candidate for being an initial economic “drawing card”, because of its value for fast transportation in geolunar space, requiring significantly fewer ships for equal transfer capability per unit time than electric transports which, however, have value, especially between geosynchronous and lunar orbit. The reduced development difficulties of controlled fusion outside the atmosphere and its advantages for extracting oxygen and other elements in quantity are summarized. Examples of lunar cycle management as fundamental exoindustrial requirement for economic resource enhancement are presented. The principal initial socio-economic value of lunar industry lies in the use of lunar resources for exoindustrial products and operations designed to accelerate, intensify and diversify Earth-related benefits. In the longer run, lunar settlements are a highly suitable proving ground for studying and testing the complex matrix of technological, biological, cultural, social and psychological aspects that must be understood and manageable before large settlements beyond Earth can have a realistic basis for viability. The lunar environment is more suitable for experimentation and comparatively more “forgiving” in case of failures than is orbital space.     

Power system design of ESMO

The European Student Moon Orbiter (ESMO) spacecraft is a student-built mini satellite being designed for a mission to the Moon. Designing and launching mini satellites are becoming a current trend in the space sector since they provide an economic way to perform innovative scientific experiments and in-flight demonstration of novel space technologies. The generation, storage, control, and distribution of the electrical power in a mini satellite represents unique challenges to the power engineer since the mass and volume restrictions are very stringent. Regardless of these problems, every subsystem and payload equipment must be operated within their specified voltage band whenever they required to be turned on. This paper presents the preliminary design of a lightweight, compact, and reliable power system for ESMO that can generate 720 W. Some of the key components of the EPS include ultra triple-junction (UTJ) GaAs solar cells controlled by maximum power point trackers, and high efficiency Li-ion secondary batteries recharged in parallel.     

ESA strategic planning for space exploration

The European Space Agency (ESA) is pursuing an independent strategic planning process for consolidating a destination driven (LEO, Moon, Mars) space exploration strategy. ESA's space exploration strategy is driven by the goals to maximise knowledge gain and to contribute to economic growth. International cooperation is a key pillar of ESA's strategy as it is considered both, an enabler for achieving common goals and a benefit, opening new perspective for addressing future challenges. The achievement of ESA's space exploration strategy is enabled through international partnerships. The interagency coordination process conducted within the framework of the International Space Exploration Coordination Group (ISECG) plays an important role in laying the foundations for future partnerships. It has achieved so far the development of a common vision for space exploration, a common plan for implementing the vision in the form of the Global Exploration Roadmap, as well as a common approach for articulating the value of global space exploration. ESA has been a strong promoter and supporter of the interagency coordination process conducted within ISECG and thanks to its unique expertise in international cooperation the Agency has contributed to its success.     

浅析高功率微波武器的研究与发展

随着外层空间日益军事化,作为反卫星武器的高功率微波武器的研究与发展备受关注,其军事价值日益显现.对高功率微波武器的作用效能及特点作了详细分析,重点评述了各主要军事强国在高功率微波武器方面的研究情况.最后分析了高功率微波武器的发展趋势.     

空间电源性能测试仿真系统设计与实现

提出一种基于空间电源控制器的半实物动态环境测试仿真系统,主要由电源控制器、太阳电池模拟阵、蓄电池模拟器、程控电子负载和仿真计算机组成。以电源控制器为被测对象,搭建的仿真系统可实时模拟航天器在空间动态环境下太阳电池阵的输出特性,包括不同轨道、太阳光照角等状态条件下的输出,对航天器上的电源性能进行测试,通过仿真结果验证空间电源系统设计的正确性。     

兆瓦级探月火箭空间核电源系统设计与性能研究

针对目前空间核电源在深空探测领域功率不足的问题，结合热离子热电转换空间核电源和碱金属热电转换空间核电源的发电方式，提出一种新型空间核电源。计算堆芯有效增殖因子、功率峰值因子、冷却剂空泡系数和停堆深度等安全性参数，并通过分析接收极功函数和碱金属热电转换系统电流密度等性能参数。之后，对比耦合发电系统与原热离子热电转换空间核电源和碱金属热电转换空间核电源的效率，发现新型耦合发电系统发电效率分别较另两种发电系统提高约6％和约10％。最后建立动态模型进行分析，确保核电源可以稳定运行，为大功率核电源设计提供理论依据。     

Societal imperatives and the need for space nuclear power and propulsion systems

The development and exploitation of nuclear power and propulsion represent certain didactic imperatives for human civilization. Among these are economic, epistemological, moral and commercial propositions. Developing space nuclear power and propulsion represents one future; the choice of not to pursue the course barring some breakthrough in physics represents a dramatically different future. The author argues that the time is now fortuitous for deployment and operation of nuclear propulsion and power, primarily nuclear electric propulsion, at significant levels, employing figures of merit that transcend simple cost models used to justify nuclear power sources in the past. The proposition is examined, in the light of US and UN restrictions, to ascertain how best to proceed. The author argues that viewpoints of certain vocal albeit uninformed public interest groups are typically self-serving and generally categorically incorrect; it can be asserted that these same groups do not truly represent the public interest at all. It is, therefore, necessary to present an even-handed assessment of both sides of the argument to determine the virtues and liabilities of embarking on such a developmental path. Given the imperatives mentioned, the author argues that nuclear power and propulsion for space systems is a societal necessity.