Space-enhanced terrestrial solar power for equatorial regions

Bonetti, F. and McInnes, C. (2019) Space-enhanced terrestrial solar power for equatorial regions. Journal of Spacecraft and Rockets, 56(1), pp. 33-43. (doi: 10.2514/1.A34032)

Abstract

This Paper investigates the concept of solar mirrors in an Earth orbit to provide large-scale terrestrial equatorial solar farms with additional solar power during the hours of darkness. A flower constellation of mirrors is considered in highly eccentric orbits (semimajor axis=20,270.4  km) in order to increase the time of visibility over the solar farms, and through this architecture, only two mirrors are needed to provide complete night coverage over three equatorial locations. Selecting the proper value for the orbit eccentricity, solar radiation pressure and Earth’s oblateness perturbations act on the mirrors so that the apsidal motion of the orbit due to these perturbations is synchronized with the apparent motion of the sun. Therefore, it can be guaranteed that the perigee always points toward the sun and that the mirrors orbit mostly above the night side of the Earth. With respect to geostationary orbit, the family of orbits considered in this Paper allows a passive means to overcome issues related to orbital perturbations. Moreover, because of the large slant range from geostationary orbits, a larger mirror is required to deliver the same energy that could be delivered from a lower orbit with a smaller mirror. As a result, a single antiheliotropic flower constellation composed of two mirrors of 50  km2 would be able to deliver energy in the range of 4.60–5.20 GW·h per day to 1000  km3 solar farms on the equator. Finally, it is estimated that, deploying 90 of these constellations, the price of electricity could be reduced from 9.1 cents to 6 cents per kW⋅h.

• Item Type: Articles
• Additional Information: Federica Bonetti was supported by an Engineering and Physics Sciences Research Council Institutional Sponsorship Grant. Colin McInnes acknowledges support from a Royal Society Wolfson Research Merit Award.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Bonetti, Federica and McInnes, Professor Colin
• Authors: Bonetti, F., and McInnes, C.
• College/School: College of Science and Engineering > School of Engineering > Systems Power and Energy
• Journal Name: Journal of Spacecraft and Rockets
• Publisher: American Institute of Aeronautics and Astronautics, Inc.
• ISSN: 0022-4650
• ISSN (Online): 1533-6794
• Published Online: 13 September 2018
• Copyright Holders: Copyright © 2018 Federica Bonetti
• First Published: First published in AIAA Journal 56(1):33-43
• Publisher Policy: Reproduced in accordance with the publisher copyright policy