 | This article possibly contains unsourced predictions, speculative material, or accounts of events that might not occur. Information must be verifiable and based on reliable published sources. (May 2016) |
| Part of a series on |
| Sustainable energy |
|---|
 |
| Part of a series on |
| Renewable energy |
|---|
 |
Space-based solar power (SBSP or SSP) is the concept of collecting solar power in outer space with solar power satellites (SPS) and distributing it to Earth. Its advantages include a higher collection of energy due to the lack of reflection and absorption by the atmosphere, the possibility of very little night, and a better ability to orient to face the Sun. Space-based solar power systems convert sunlight to some other form of energy (such as microwaves) which can be transmitted through the atmosphere to receivers on the Earth's surface.
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,[1][2] but as of 2014[update] 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 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 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 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,[3] Russia, India, the United Kingdom,[4] and the US.
In 2008, Japan passed its Basic Space Law which established space solar power as a national goal.[5] 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 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.[6][7] 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.[8]
In May 2020, the US Naval Research Laboratory conducted its first test of solar power generation in a satellite.[9] 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.[10][11] A Caltech team successfully demonstrated beaming power to earth in 2023.[11]
- ^ "Space-based solar power". ESA–Advanced Concepts Team. 15 April 2013. Retrieved August 23, 2015.
- ^ "Space-Based Solar Power". United States Department of Energy (DOE). 6 March 2014.
- ^ Eric Rosenbaum; Donovan Russo (March 17, 2019). "China plans a solar power play in space that NASA abandoned decades ago". CNBC.com. Retrieved 19 March 2019.
- ^ "UK government commissions space solar power stations research". gov.uk (Press release). UK Space Agency. 14 November 2020. Retrieved 30 November 2020.
- ^ "Basic Plan for Space Policy" (PDF). June 2, 2009. Retrieved May 21, 2016.
- ^ "我国有望率先建成空间太阳能电站-科技新闻-中国科技网首页". www.stdaily.com. Retrieved 2021-08-18.
- ^ Needham, Kirsty (2019-02-15). "Plans for first Chinese solar power station in space revealed". The Sydney Morning Herald. Retrieved 2021-08-18.
- ^ "China to build space-based solar power station by 2035 - Xinhua | English.news.cn". www.xinhuanet.com. Archived from the original on December 2, 2019. Retrieved 2021-08-18.
- ^ "Solar Power Experiment Launched by Navy Research Lab on X-37B Space Plane". Forbes. May 27, 2020.
- ^ "Caltech Announces Breakthrough $100 Million Gift to Fund Space-based Solar Power Project". California Institute of Technology. 3 August 2021. Retrieved 2021-08-18.
- ^ a b "In a First, Caltech's Space Solar Power Demonstrator Wirelessly Transmits Power in Space". California Institute of Technology. 1 June 2023. Retrieved 2023-06-01.