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94-617: Solar panels on spacecraft have been in use since 1958, when Vanguard I used them to power one of its radio transmitters; however, the term (and acronyms) above are generally used in the context of large-scale transmission of energy for use on Earth. Various SBSP proposals have been researched since the early 1970s, but as of 2014 none is economically viable with the space launch costs. Some technologists propose lowering launch costs with space manufacturing or with radical new space launch technologies other than rocketry . Besides cost, SBSP also introduces several technological hurdles, including

188-453: A microwave transmitter or laser emitter, and transmit this energy to a collector (or microwave rectenna ) on Earth's surface. Contrary to appearances in fiction, most designs propose beam energy densities that are not harmful if human beings were to be inadvertently exposed, such as if a transmitting satellite's beam were to wander off-course. But the necessarily vast size of the receiving antennas would still require large blocks of land near

282-457: A 1 km diameter transmitting antenna and a 10 km diameter receiving rectenna for a microwave beam at 2.45 GHz . These sizes can be somewhat decreased by using shorter wavelengths, although they have increased atmospheric absorption and even potential beam blockage by rain or water droplets. Because of the thinned array curse , it is not possible to make a narrower beam by combining the beams of several smaller satellites. The large size of

376-608: A European-centric company initially, rebuilding and strengthening its core practices in oil and gas, telecommunications, automotive, manufacturing, and chemicals. It did however maintain offices in Boston and Houston in the USA. Later ADL grew and expanded throughout Europe, the Middle East, and Asia and continued to be recognized for its expertise in areas combining aspects of technology, innovation, and strategy. A group of partners led

470-566: A battery. The satellite was powered by silicon solar cells with ≈10% conversion efficiency. A few weeks after the US launched Vanguard 1, Sputnik 3 was launched by the Soviet space program outfitted with Silver zinc batteries with experimental silicon solar cells. The purpose of the batteries was both to power the transmitter and other equipment, but also to test the long term effects of radiation and micrometeorite damage on solar batteries. Some of

564-454: A boiler. The use of solar dynamic could reduce mass per watt. Wireless power transmission was proposed early on as a means to transfer energy from collection to the Earth's surface, using either microwave or laser radiation at a variety of frequencies. William C. Brown demonstrated in 1964, during Walter Cronkite 's CBS News program, a microwave-powered model helicopter that received all

658-514: A graduate of the University of Vermont who had met when they both worked for Richmond Paper Company . Their new company, Little & Griffin, was located in Boston where MIT was then located. Griffin and Little prepared a manuscript for The Chemistry of Paper-making which was for many years an authoritative text in the area. The book had not been entirely finished when Griffin was killed in

752-510: A group with other similar satellites. There are many pros to Laser Solar Satellites, specifically regarding their lower overall costs in comparison to other satellites. While the cost is lower than other satellites, there are various safety concerns, and other concerns regarding this satellite. Laser-emitting solar satellites only need to venture about 400 km into space, but because of their small generation capacity, hundreds or thousands of laser satellites would need to be launched in order to create

846-575: A high-risk venture." In 1997, NASA conducted its "Fresh Look" study to examine the modern state of SBSP feasibility. In assessing "What has changed" since the DOE study, NASA asserted that the "US National Space Policy now calls for NASA to make significant investments in technology (not a particular vehicle) to drive the costs of ETO [Earth to Orbit] transportation down dramatically. This is, of course, an absolute requirement of space solar power." Conversely, Pete Worden of NASA claimed that space-based solar

940-428: A key figure of merit of the solar panels is the specific power (watts generated divided by solar array mass), which indicates on a relative basis how much power one array will generate for a given launch mass relative to another. Another key metric is stowed packing efficiency (deployed watts produced divided by stowed volume), which indicates how easily the array will fit into a launch vehicle. Yet another key metric

1034-562: A laboratory accident in 1893. Little, who had studied Chemistry at MIT, collaborated with MIT and William Hultz Walker of the MIT Chemistry department, forming a partnership, Little & Walker, which lasted from 1900 to 1905, while both MIT and Little's company were still located in Boston. The partnership dissolved in 1905 when Walker dedicated all of his time to being in charge of the new Research Laboratory of Applied Chemistry at MIT. Little continued on his own and incorporated

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1128-549: A lengthy article "It's Always Sunny in Space" by Susumu Sasaki. The article stated, "It's been the subject of many previous studies and the stuff of sci-fi for decades, but space-based solar power could at last become a reality—and within 25 years, according to a proposal from researchers at the Tokyo -based Japan Aerospace Exploration Agency (JAXA)." JAXA announced on 12 March 2015 that they wirelessly beamed 1.8 kilowatts 50 meters to

1222-693: A management buyout from the Altran group in 2011. The MBO was completed on 30 December 2011 with the vast majority of ADL directors becoming partners and shareholders. A small number of senior principals, as well as the CFO and COO, also became shareholders. The firm is led by the elected Global CEO, Ignacio Garcia-Alves, who was also the leader of the MBO team. Currently the firm operates with an elected board of directors and several elected committees - Compensation Committee, Partnership Committee, and an Audit Committee. In

1316-448: A method would depend on a thorough mineral survey of the candidate asteroids; thus far, we have only estimates of their composition. One proposal is to capture the asteroid Apophis into Earth orbit and convert it into 150 solar power satellites of 5 GW each or the larger asteroid 1999 AN10, which is 50 times the size of Apophis and large enough to build 7,500 5-gigawatt solar power satellites The potential exposure of humans and animals on

1410-541: A mountaintop in Maui and the island of Hawaii (92 miles away), by a team under John C. Mankins . Technological challenges in terms of array layout, single radiation element design, and overall efficiency, as well as the associated theoretical limits are presently a subject of research, as it was demonstrated by the Special Session on "Analysis of Electromagnetic Wireless Systems for Solar Power Transmission" held during

1504-807: A national goal. JAXA has a roadmap to commercial SBSP. In 2015, the China Academy for Space Technology (CAST) showcased its roadmap at the International Space Development Conference. In February 2019, Science and Technology Daily (科技日报, Keji Ribao), the official newspaper of the Ministry of Science and Technology of the People's Republic of China , reported that construction of a testing base had started in Chongqing's Bishan District. CAST vice-president Li Ming

1598-461: A pilot beam transmitter. The long-term effects of beaming power through the ionosphere in the form of microwaves has yet to be studied. The typical reference system-of-systems involves a significant number (several thousand multi-gigawatt systems to service all or a significant portion of Earth's energy requirements) of individual satellites in GEO. The typical reference design for the individual satellite

1692-502: A researcher at Bell Labs in 1940. It was only 1% efficient. In April 25, 1954 in Murray Hill, New Jersey. They demonstrated their solar panel by using it to power a small toy Ferris wheel and a solar powered radio transmitter. They were initially about 6% efficient, but improvements began to raise this number almost immediately. Bell had been interested in the idea as a system to provide power at remote telephone repeater stations, but

1786-407: A small receiver by converting electricity to microwaves and then back to electricity. This is the standard plan for this type of power. On 12 March 2015 Mitsubishi Heavy Industries demonstrated transmission of 10 kilowatts (kW) of power to a receiver unit located at a distance of 500 meters (m) away. The SBSP concept is attractive because space has several major advantages over the Earth's surface for

1880-555: A structural reorganization of Arthur D. Little Inc. In 1987, ADL claimed that sabotage was likely the cause of the Bhopal disaster , which resulted in the death of thousands. ADL's investigation was funded by Union Carbide , the company that owned the chemical plant responsible for the chemical disaster. Analysis by Arthur D. Little argues that the Negligence argument was impossible for several tangible reasons. In 2001, ADL wrote

1974-413: A sustainable impact. A single satellite launch can range from fifty to four hundred million dollars. Lasers could be helpful for the energy from the sun harvested in space, to be returned back to Earth in order for terrestrial power demands to be met. The main advantage of locating a space power station in geostationary orbit is that the antenna geometry stays constant, and so keeping the antennas lined up

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2068-413: A system of as few as thirty solar power satellites of 10 GW capacity each. In 1980, when it became obvious NASA's launch cost estimates for the space shuttle were grossly optimistic, O'Neill et al. published another route to manufacturing using lunar materials with much lower startup costs. This 1980s SPS concept relied less on human presence in space and more on partially self-replicating systems on

2162-417: A tax-exempt retirement trust for the benefit of its employees, was set up. As the pioneer firm in professional services, Arthur D. Little played a key role in numerous 20th-century business initiatives: In 1911 ADL organized General Motors ' first R&D lab, leading to the formation of the firm's dedicated management consulting division, and the birth of the management consulting industry. In 1916 ADL

2256-418: A very large antenna (up to one square kilometer) on the satellite to a much larger one, now known as a rectenna , on the ground. Glaser then was a vice president at Arthur D. Little , Inc. NASA signed a contract with ADL to lead four other companies in a broader study in 1974. They found that, while the concept had several major problems – chiefly the expense of putting the required materials in orbit and

2350-717: Is about five orders of magnitude more expensive than solar power from the Arizona desert, with a major cost being the transportation of materials to orbit. Worden referred to possible solutions as speculative and not available for decades at the earliest. On November 2, 2012, China proposed a space collaboration with India that mentioned SBSP, "may be Space-based Solar Power initiative so that both India and China can work for long term association with proper funding along with other willing space faring nations to bring space solar power to earth." In 1999, NASA initiated its Space Solar Power Exploratory Research and Technology program (SERT) for

2444-411: Is an international management consulting firm originally headquartered in Boston , Massachusetts, United States, founded in 1886 and formally incorporated in 1909 by Arthur Dehon Little , an MIT chemist who extended the applications of cellulose acetate , especially its use as artificial silk. Arthur D. Little pioneered the concept of contracted professional services. The company played key roles in

2538-459: Is construction largely from locally available lunar materials, using in-situ resource utilization , with a teleoperated mobile factory and crane to assemble the microwave reflectors, and rovers to assemble and pave solar cells, which would significantly reduce launch costs compared to SBSP designs. Power relay satellites orbiting around earth and the Moon reflecting the microwave beam are also part of

2632-492: Is cost (dollars per watt). To increase the specific power, typical solar panels on spacecraft use close-packed solar cell rectangles that cover nearly 100% of the Sun-visible area of the solar panels, rather than the solar wafer circles which, even though close-packed, cover about 90% of the Sun-visible area of typical solar panels on Earth. However, some solar panels on spacecraft have solar cells that cover only 30% of

2726-501: Is in the 1-10 GW range and usually involves planar or concentrated solar photovoltaics (PV) as the energy collector / conversion. The most typical transmission designs are in the 1–10 GHz (2.45 or 5.8 GHz) RF band where there are minimum losses in the atmosphere. Materials for the satellites are sourced from, and manufactured on Earth and expected to be transported to LEO via re-usable rocket launch, and transported between LEO and GEO via chemical or electrical propulsion. In summary,

2820-428: Is simpler. Another advantage is that nearly continuous power transmission is immediately available as soon as the first space power station is placed in orbit, LEO requires several satellites before they are producing nearly continuous power. Power beaming from geostationary orbit by microwaves carries the difficulty that the required 'optical aperture' sizes are very large. For example, the 1978 NASA SPS study required

2914-484: Is the first mission to Jupiter (arrived at Jupiter on July 4, 2016) to use solar panels instead of the traditional RTGs that are used by previous outer Solar System missions, making it the furthest spacecraft to use solar panels to date. It has 50 square metres (540 sq ft) of panels. The InSight lander , Ingenuity helicopter , Tianwen-1 orbiter , and Zhurong rover all currently operating on Mars also utilize solar panels. Another spacecraft of interest

Space-based solar power - Misplaced Pages Continue

3008-425: Is to use a retrodirective phased array antenna/rectenna. A "pilot" microwave beam emitted from the center of the rectenna on the ground establishes a phase front at the transmitting antenna. There, circuits in each of the antenna's subarrays compare the pilot beam's phase front with an internal clock phase to control the phase of the outgoing signal. If the phase offset to the pilot is chosen the same for all elements,

3102-490: The Earth's radiation belts (also called Van Allen belts), galactic cosmic rays (GCR), solar wind and solar flares . The Van Allen belts and the solar wind contain mostly protons and electrons, while GCR are in majority very high energy protons, alpha particles and heavier ions. Solar panels will experience efficiency degradation over time as a result of these types of radiation, but the degradation rate will depend strongly on

3196-717: The US Naval Research Laboratory conducted its first test of solar power generation in a satellite. In August 2021, the California Institute of Technology (Caltech) announced that it planned to launch a SBSP test array by 2023, and at the same time revealed that Donald Bren and his wife Brigitte, both Caltech trustees, had been since 2013 funding the institute's Space-based Solar Power Project, donating over $ 100 million. A Caltech team successfully demonstrated beaming power to earth in 2023. In 1941, science fiction writer Isaac Asimov published

3290-410: The 2010 IEEE Symposium on Antennas and Propagation. In 2013, a useful overview was published, covering technologies and issues associated with microwave power transmission from space to ground. It includes an introduction to SPS, current research and future prospects. Moreover, a review of current methodologies and technologies for the design of antenna arrays for microwave power transmission appeared in

3384-606: The Earth-orbiting, Hubble Space Telescope . The Rosetta space probe , launched 2 March 2004, used its 64 square metres (690 sq ft) of solar panels as far as the orbit of Jupiter (5.25 AU ); previously the furthest use was the Stardust spacecraft at 2 AU. Solar power for propulsion was also used on the European lunar mission SMART-1 with a Hall effect thruster . The Juno mission, launched in 2011,

3478-550: The Moon as part of the Apollo 11 mission and which remains active and functioning to this day. In 1980, ADL produced the European Commission 's first white paper on telecommunications deregulation , having completed the first worldwide telecommunications database on phones installed, markets, technical trends, services and regulatory information. It also helped privatize British Rail , generally regarded as one of

3572-530: The Moon may reduce the cost of building a solar power satellite from lunar materials. Some proposed techniques include the lunar mass driver and the lunar space elevator , first described by Jerome Pearson. It would require establishing silicon mining and solar cell manufacturing facilities on the Moon . Physicist Dr David Criswell suggests the Moon is the optimum location for solar power stations, and promotes lunar-based solar power. The main advantage he envisions

3666-456: The OSHA long-term levels as over 95% of the beam energy will fall on the rectenna. However, any accidental or intentional mis-pointing of the satellite could be deadly to life on Earth within the beam. Exposure to the beam can be minimized in various ways. On the ground, assuming the beam is pointed correctly, physical access must be controllable (e.g., via fencing). Typical aircraft flying through

3760-529: The Proceedings of the IEEE. Laser power beaming was envisioned by some at NASA as a stepping stone to further industrialization of space. In the 1980s, researchers at NASA worked on the potential use of lasers for space-to-space power beaming, focusing primarily on the development of a solar-powered laser. In 1989, it was suggested that power could also be usefully beamed by laser from Earth to space. In 1991,

3854-476: The SELENE project (SpacE Laser ENErgy) had begun, which included the study of laser power beaming for supplying power to a lunar base. The SELENE program was a two-year research effort, but the cost of taking the concept to operational status was too high, and the official project ended in 1993 before reaching a space-based demonstration. Laser Solar Satellites are smaller in size, meaning that they have to work as

Space-based solar power - Misplaced Pages Continue

3948-612: The Sun-visible area. Solar panels need to have a lot of surface area that can be pointed towards the Sun as the spacecraft moves. More exposed surface area means more electricity can be converted from light energy from the Sun. Since spacecraft have to be small, this limits the amount of power that can be produced. All electrical circuits generate waste heat ; in addition, solar arrays act as optical and thermal as well as electrical collectors. Heat must be radiated from their surfaces. High-power spacecraft may have solar arrays that compete with

4042-418: The active payload itself for thermal dissipation. The innermost panel of arrays may be "blank" to reduce the overlap of views to space. Such spacecraft include the higher-power communications satellites (e.g., later-generation TDRS ) and Venus Express , not high-powered but closer to the Sun. Spacecraft are built so that the solar panels can be pivoted as the spacecraft moves. Thus, they can always stay in

4136-467: The amount of concentration. Concentrators work best when there is a single source of light and the concentrator can be pointed right at it. This is ideal in space, where the Sun is a single light source. Solar cells are the most expensive part of solar arrays, and arrays are often a very expensive part of the spacecraft. This technology may allow costs to be cut significantly due to the utilization of less material. Arthur D. Little Arthur D. Little

4230-691: The architecture choices are: There are several interesting design variants from the reference system: Alternate energy collection location: While GEO is most typical because of its advantages of nearness to Earth, simplified pointing and tracking, very small time in occultation, and scalability to meet all global demand several times over, other locations have been proposed: Energy collection: The most typical designs for solar power satellites include photovoltaics. These may be planar (and usually passively cooled), concentrated (and perhaps actively cooled). However, there are multiple interesting variants. Solar panels on spacecraft Spacecraft operating in

4324-523: The batteries were covered with protective glass while others were left exposed. The batteries were able to power the 20 MHz Mayak transmitter and Sergei Vernov's Scintillation counter , and these functioned for the entire lifetime of the satellite; until it reentered the Atmosphere nearly two years later. The success of the Vanguard system inspired Spectrolab , an optics company, to take up

4418-641: The beam provide passengers with a protective metal shell (i.e., a Faraday Cage ), which will intercept the microwaves. Other aircraft ( balloons , ultralight , etc.) can avoid exposure by using controlled airspace, as is currently done for military and other controlled airspace. In addition, a design constraint is that the microwave beam must not be so intense as to injure wildlife, particularly birds. Suggestions have been made to locate rectennas offshore, but this presents serious problems, including corrosion, mechanical stresses, and biological contamination. A commonly proposed approach to ensuring fail-safe beam targeting

4512-683: The collection of solar power: The SBSP concept also has a number of problems: Space-based solar power essentially consists of three elements: The space-based portion will not need to support itself against gravity (other than relatively weak tidal stresses). It needs no protection from terrestrial wind or weather, but will have to cope with space hazards such as micrometeors and solar flares . Two basic methods of conversion have been studied: photovoltaic (PV) and solar dynamic (SD). Most analyses of SBSP have focused on photovoltaic conversion using solar cells that directly convert sunlight into electricity. Solar dynamic uses mirrors to concentrate light on

4606-928: The company reaching 150 partners roughly two years later. In March 2022 Arthur D. Little terminated its operations in Russia and closed its Moscow office. Arthur D. Little is organized across a number of industry specialty groups including Aerospace & Defense, Automotive, Chemicals, Consumer Goods & Retail, Energy & Utilities, Financial Services, Healthcare & Life Sciences, Industrial Goods & Services, Oil & Gas, Private Equity, Public Services, Telecommunications, Information Technology, Media & Electronics (TIME), Travel & Transportation. Major service lines are in Corporate Finance, Digital Transformation, Digital Problem Solving, Operations and Risk Management, Strategy and Organisation, Sustainability, Innovation Management. In 2023, ADL Europe

4700-524: The company, Arthur D. Little (ADL), in 1909. He conducted analytical studies, the precursor of the consulting studies for which the firm would later become famous. He also taught papermaking at MIT from 1893 to 1916. In 1917, the company, originally based at 103 Milk Street in Boston, moved to its own building, the Arthur D. Little Inc., Building , at 30 Memorial Drive on the Charles River next to

4794-495: The cost of the devices was far too high to be practical in this role. Aside from small experimental kits and uses, the cells remained largely unused. This changed with the development of the first US spacecraft, the Vanguard 1 satellite in 1958. Calculations by Dr. Hans Ziegler demonstrated that a system using solar cells recharging a battery pack would provide the required power in a much lighter overall package than using just

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4888-410: The development of business strategy, operations research , the word processor , the first synthetic penicillin , LexisNexis , SABRE , and NASDAQ . Today the company is a multinational management consulting firm operating as a partnership. The roots of the company were started in 1886 by Arthur Dehon Little , an MIT chemist, and co-worker Roger B. Griffin (Russell B. Griffin), another chemist and

4982-771: The development of solar cells specifically designed for space applications. They had their first major design win on Pioneer 1 in 1958, and would later be the first cells to travel to the Moon, on the Apollo 11 mission's ALSEP package. As satellites grew in size and power, Spectrolab began looking for ways to introduce much more powerful cells. This led them to pioneer the development of multi-junction cells that increased efficiency from around 12% for their 1970s silicon cells to about 30% for their current gallium arsenide (GaAs) cells. These types of cells are now used almost universally on all solar-powered spacecraft. Solar panels on spacecraft supply power for two main uses: For both uses,

5076-425: The diameter of the proposed SPSP array is increased by 2.5x, the energy density on the ground increases to 1 W/cm. At this level, the median lethal dose for mice is 30-60 seconds of microwave exposure. While designing an array with 2.5x larger diameter should be avoided, the dual-use military potential of such a system is readily apparent. With good array sidelobe design, outside the receiver may be less than

5170-499: The direct cost of a new coal or nuclear power plant ranges from $ 3 billion to $ 6 billion per GW (not including the full cost to the environment from CO 2 emissions or storage of spent nuclear fuel, respectively). Gerard O'Neill , noting the problem of high launch costs in the early 1970s, proposed building the SPS's in orbit with materials from the Moon . Launch costs from the Moon are potentially much lower than from Earth because of

5264-400: The direct path of the light rays no matter how the spacecraft is pointed. Spacecraft are usually designed with solar panels that can always be pointed at the Sun, even as the rest of the body of the spacecraft moves around, much as a tank turret can be aimed independently of where the tank is going. A tracking mechanism is often incorporated into the solar arrays to keep the array pointed towards

5358-422: The early 1990s, Gallium arsenide -based solar cells became favored over silicon because they have a higher efficiency and degrade more slowly than silicon in the space radiation environment. The most efficient solar cells currently in production are now multi-junction photovoltaic cells . These use a combination of several layers of indium gallium phosphide, gallium arsenide and germanium to harvest more energy from

5452-479: The end users. The service life of space-based collectors in the face of long-term exposure to the space environment, including degradation from radiation and micrometeoroid damage, could also become a concern for SBSP. As of 2020, SBSP is being actively pursued by Japan, China, Russia, India, the United Kingdom, and the US. In 2008, Japan passed its Basic Space Law which established space solar power as

5546-510: The engineering feasibility of such a project. They include: The project was not continued with the change in administrations after the 1980 United States elections . The Office of Technology Assessment concluded that "Too little is currently known about the technical, economic, and environmental aspects of SPS to make a sound decision whether to proceed with its development and deployment. In addition, without further research an SPS demonstration or systems-engineering verification program would be

5640-615: The first management education program to focus exclusively on training general managers from developing countries. Originally known as the Arthur D. Little Management Education Institute, this was a fully accredited academic institution with master's degree granting status. In 1996, the Arthur D. Little School of Management formed a partnership with Boston College 's Carroll School of Management in order to gain access to faculty and facilities. The Arthur D. Little School of Management became Hult International Business School in 2002, following

5734-507: The first time in over a decade. In 2024, ADL North America was ranked #28 overall. ADL was also recognized for International Opportunities (#2), Internal Mobility (#6), Management Consulting (#14), Environmental Sustainability (#19), Formal Training (#25), and Prestige (#45). Arthur D. Little publishes a number of regular global studies including: In addition, Arthur D. Little frequently publishes topical or industry-centric reports. Recent examples include: In 1961, Arthur D. Little launched

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5828-486: The five years following the 2011 MBO, ADL opened new offices in Turkey, Oslo, Buenos Aires, Mexico City, Singapore, Hong Kong, Beirut, Riyadh, Prague and Bahrain. In addition, ADL recently re-established itself in the US market and has opened offices in Boston, New York, and San Francisco. In March 2021 Arthur D. Little announced it had reached a milestone of over 100 partners. Growth accelerated after this milestone, with

5922-699: The following purposes: SERT went about developing a solar power satellite (SPS) concept for a future gigawatt space power system, to provide electrical power by converting the Sun's energy and beaming it to Earth's surface, and provided a conceptual development path that would utilize current technologies. SERT proposed an inflatable photovoltaic gossamer structure with concentrator lenses or solar heat engines to convert sunlight into electricity. The program looked both at systems in Sun-synchronous orbit and geosynchronous orbit . Some of SERT's conclusions: The May 2014 IEEE Spectrum magazine carried

6016-595: The ground to the high power microwave beams is a significant concern with these systems. At the Earth's surface, a suggested SPSP microwave beam would have a maximum intensity at its center, of 23 mW/cm. While this is less than 1/4 the solar irradiation constant , microwaves penetrate much deeper into tissue than sunlight, and at this level would exceed the current United States Occupational Safety and Health Act (OSHA) workplace exposure limits for microwaves at 10 mW/cm At 23 mW/cm, studies show humans experience significant deficits in spatial learning and memory. If

6110-476: The impact of the dot.com bubble on technology sector activity this led Arthur D. Little to file Chapter 11 bankruptcy protection in 2002. At an auction in 2002, TIAX LLC , formed by Kenan Sahin , acquired the assets, contracts, and staff of Arthur D. Little's U.S. Technology & Innovation business. Paris -based Altran Technologies bought the non-U.S. assets and brand name of Arthur D. Little. Under Altran's ownership, Arthur D. Little operated primarily as

6204-480: The inner Solar System usually rely on the use of power electronics -managed photovoltaic solar panels to derive electricity from sunlight . Outside the orbit of Jupiter , solar radiation is too weak to produce sufficient power within current solar technology and spacecraft mass limitations, so radioisotope thermoelectric generators (RTGs) are instead used as a power source. The first practical silicon-based solar cells were introduced by Russell Shoemaker Ohl,

6298-687: The lack of experience on projects of this scale in space – it showed enough promise to merit further investigation and research. Between 1978 and 1986, the Congress authorized the Department of Energy (DoE) and NASA to jointly investigate the concept. They organized the Satellite Power System Concept Development and Evaluation Program. The study remains the most extensive performed to date (budget $ 50 million). Several reports were published investigating

6392-576: The lower gravity and lack of atmospheric drag . This 1970s proposal assumed the then-advertised future launch costing of NASA's space shuttle. This approach would require substantial upfront capital investment to establish mass drivers on the Moon. Nevertheless, on 30 April 1979, the Final Report ("Lunar Resources Utilization for Space Construction") by General Dynamics' Convair Division, under NASA contract NAS9-15560, concluded that use of lunar resources would be cheaper than Earth-based materials for

6486-564: The lunar surface under remote control of workers stationed on Earth. The high net energy gain of this proposal derives from the Moon's much shallower gravitational well . Having a relatively cheap per pound source of raw materials from space would lessen the concern for low mass designs and result in a different sort of SPS being built. The low cost per pound of lunar materials in O'Neill's vision would be supported by using lunar material to manufacture more facilities in orbit than just solar power satellites. Advanced techniques for launching from

6580-499: The material launched need not be delivered to its eventual orbit immediately, which raises the possibility that high efficiency (but slower) engines could move SPS material from LEO to GEO at an acceptable cost. Examples include ion thrusters or nuclear propulsion . Infrastructure including solar panels, power converters, and power transmitters will have to be built in order to begin the process. This will be extremely expensive and maintaining them will cost even more. To give an idea of

6674-403: The mining ship would be traditional aerospace-grade payload. The rest would be reaction mass for the mass-driver engine, which could be arranged to be the spent rocket stages used to launch the payload. Assuming that 100% of the returned asteroid was useful, and that the asteroid miner itself couldn't be reused, that represents nearly a 95% reduction in launch costs. However, the true merits of such

6768-488: The most complex privatization exercises in the world. By 2001, Arthur D. Little reached its peak as a global consulting firm with very significant growth in the technology sector. However, a new management team mismanaged the company's core business and engaged in manipulation of the Memorial Drive Trust. The ADL Board of Trustees replaced this management team. But the damage had been done, and combined with

6862-536: The new campus of MIT, which had also relocated from Boston to Cambridge. The building was added to the National Register of Historic Places in 1976. In November 1953, ADL opened a 40-acre site for its Acorn Park labs in west Cambridge, Massachusetts , about 6 miles (10 km) from MIT. The new site took its name from the company motto - "Glandes Sparge Ut Quercus Crescant," translated as "Scatter Acorns That Oaks May Grow." The Memorial Drive Trust,

6956-456: The operation of solar-powered spacecraft feasible at larger distances from the sun. Solar array mass could be reduced with thin-film photovoltaic cells, flexible blanket substrates, and composite support structures. Solar array efficiency could be improved by using new photovoltaic cell materials and solar concentrators that intensify the incident sunlight. Photovoltaic concentrator solar arrays for primary spacecraft power are devices which intensify

7050-579: The power it needed for flight from a microwave beam. Between 1969 and 1975, Bill Brown was technical director of a JPL Raytheon program that beamed 30 kW of power over a distance of 1 mile (1.6 km) at 9.6% efficiency. Microwave power transmission of tens of kilowatts has been well proven by existing tests at Goldstone in California (1975) and Grand Bassin on Reunion Island (1997). More recently, microwave power transmission has been demonstrated, in conjunction with solar energy capture, between

7144-444: The problem of transmitting energy from orbit. Since wires extending from Earth's surface to an orbiting satellite are not feasible with current technology, SBSP designs generally include the wireless power transmission with its associated conversion inefficiencies, as well as land use concerns for antenna stations to receive the energy at Earth's surface. The collecting satellite would convert solar energy into electrical energy, power

7238-484: The project. A demo project of 1 GW starts at $ 50 billion. The Shimizu Corporation use combination of lasers and microwave for the Luna Ring concept, along with power relay satellites. Asteroid mining has also been seriously considered. A NASA design study evaluated a 10,000-ton mining vehicle (to be assembled in orbit) that would return a 500,000-ton asteroid fragment to geostationary orbit. Only about 3,000 tons of

7332-457: The same means. In a 2012 report presented to NASA on space solar power, the author mentions another potential use for the technology behind space solar power could be for solar electric propulsion systems that could be used for interplanetary human exploration missions. One problem with the SBSP concept is the cost of space launches and the amount of material that would need to be launched. Much of

7426-453: The satellite would be received in the dipoles with about 85% efficiency. With a conventional microwave antenna, the reception efficiency is better, but its cost and complexity are also considerably greater. Rectennas would likely be several kilometers across. A laser SBSP could also power a base or vehicles on the surface of the Moon or Mars, saving on mass costs to land the power source. A spacecraft or another satellite could also be powered by

7520-429: The scale of the problem, assuming a solar panel mass of 20 kg per kilowatt (without considering the mass of the supporting structure, antenna, or any significant mass reduction of any focusing mirrors) a 4 GW power station would weigh about 80,000 metric tons , all of which would, in current circumstances, be launched from the Earth. This is, however, far from the state of the art for flown spacecraft, which as of 2015

7614-502: The science fiction short story " Reason ", in which a space station transmits energy collected from the Sun to various planets using microwave beams. The SBSP concept, originally known as satellite solar-power system (SSPS), was first described in November 1968. In 1973 Peter Glaser was granted U.S. patent number 3,781,647 for his method of transmitting power over long distances (e.g. from an SPS to Earth's surface) using microwaves from

7708-487: The solar cell technology and on the location of the spacecraft. With borosilicate glass panel coverings, this may be between 5-10% efficiency loss per year. Other glass coverings, such as fused silica and lead glasses, may reduce this efficiency loss to less than 1% per year. The degradation rate is a function of the differential flux spectrum and the total ionizing dose. Up until the early 1990s, solar arrays used in space primarily used crystalline silicon solar cells. Since

7802-486: The solar spectrum. Leading edge multi-junction cells are capable of exceeding 39.2% under non-concentrated AM1.5G illumination and 47.1% using concentrated AM1.5G illumination. To date, solar power, other than for propulsion, has been practical for spacecraft operating no farther from the Sun than the orbit of Jupiter . For example, Juno , Magellan , Mars Global Surveyor , and Mars Observer used solar power as does

7896-459: The station and the fourth set of arrays were installed in March 2009. 240 kilowatts of electricity can be generated from these solar arrays. That comes to 120 kilowatts average system power, including 50% ISS time in Earth's shadow. For future missions, it is desirable to reduce solar array mass, and to increase the power generated per unit area. This will reduce overall spacecraft mass, and may make

7990-590: The sun. Sometimes, satellite operators purposefully orient the solar panels to "off point," or out of direct alignment from the Sun. This happens if the batteries are completely charged and the amount of electricity needed is lower than the amount of electricity made; off-pointing is also sometimes used on the International Space Station for orbital drag reduction . Space contains varying levels of great electromagnetic radiation as well as ionizing radiation . There are 4 sources of radiations:

8084-436: The sunlight on the photovoltaics. This design uses a flat lens, called a Fresnel lens , which takes a large area of sunlight and concentrates it onto a smaller spot, allowing a smaller area of solar cell to be used. Solar concentrators put one of these lenses over every solar cell. This focuses light from the large concentrator area down to the smaller cell area. This allows the quantity of expensive solar cells to be reduced by

8178-402: The transmitted beam should be centered precisely on the rectenna and have a high degree of phase uniformity; if the pilot beam is lost for any reason (if the transmitting antenna is turned away from the rectenna, for example) the phase control value fails and the microwave power beam is automatically defocused. Such a system would not focus its power beam very effectively anywhere that did not have

8272-457: The transmitting and receiving antennas means that the minimum practical power level for an SPS will necessarily be high; small SPS systems will be possible, but uneconomic. A collection of LEO ( low Earth orbit ) space power stations has been proposed as a precursor to GEO ( geostationary orbit ) space-based solar power. The Earth-based rectenna would likely consist of many short dipole antennas connected via diodes . Microwave broadcasts from

8366-405: Was Dawn which went into orbit around 4 Vesta in 2011. It used ion thrusters to get to Ceres . The potential for solar powered spacecraft beyond Jupiter has been studied. The International Space Station also uses solar arrays to power everything on the station. The 262,400 solar cells cover around 27,000 square feet (2,500 m ) of space. There are four sets of solar arrays that power

8460-498: Was 150 W/kg (6.7 kg/kW), and improving rapidly. Very lightweight designs could likely achieve 1 kg/kW, meaning 4,000 metric tons for the solar panels for the same 4 GW capacity station. Beyond the mass of the panels, overhead (including boosting to the desired orbit and stationkeeping) must be added. To these costs must be added the environmental impact of heavy space launch missions, if such costs are to be used in comparison to earth-based energy production. For comparison,

8554-662: Was commissioned by the Canadian Pacific Railway to do a survey of Canada's natural resources. In 1921 the firm succeeded in using a bucket of sows' ears to make a silk purse. This revolutionary achievement later became part of the Smithsonian Institute's collection. In 1968 ADL designed the NASDAQ stock exchange systems for London and Tokyo. In 1969 ADL developed the Apollo 11 Laser Ranging Retro-Reflector experiment which were installed on

8648-440: Was quoted as saying China expects to be the first nation to build a working space solar power station with practical value. Chinese scientists were reported as planning to launch several small- and medium-sized space power stations between 2021 and 2025. In December 2019, Xinhua News Agency reported that China plans to launch a 200-tonne SBSP station capable of generating megawatts (MW) of electricity to Earth by 2035. In May 2020,

8742-474: Was ranked #2 for Level of Challenge, #11 for Internal Mobility, #12 for Innovation, #13 for Compensation, #14 for International Opportunities, and #19 for Prestige. ADL re-established itself in the US market in 2016 and has since been recognized by Forbes every year since then as one of "America's Best Management Consulting Firms". In 2022, ADL North America re-emerged in Vault's North America rankings at #19 for

8836-506: Was rated #11 in Vault's 2023 Consulting rankings for Europe with recognition for Innovation (#9), Level of challenge (#9), Technology, Media & Telecommunications Consulting (#10), Interaction with Clients (#13), Informal Training (#14), International Opportunities (#14), Firm Culture (#15), Prestige (#15), Promotion Policies (#15), Strategy consulting (#15) In 2023, ADL Asia was rated #11 in Vault's 2023 Consulting rankings Asia. On Vault's global rankings of key employment factors, ADL Asia

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