Mirror satellites in polar orbit beaming sunlight to terrestrial solar fields at dawn and dusk

Abstract

Large terrestrial solar electric power fields are being built around the world. However, sunlight is only available during normal daylight hours but not in the evenings. If lightweight mirrors can be deployed in space in a sunsynchronous dawn/dusk orbit, these mirrors can reflect sunlight down to these terrestrial solar farms to provide solar electricity in the evening and early morning, extending the field operating hours and reducing the cost of solar electric power. The idea of mirrors in space reflecting sunlight to earth is not new. What is new here is the idea of a constellation of 18 mirror array satellites in a 1000 km high sun-synchronous dawn/dusk orbit in combination with multiple 5-GW solar farms distributed around the world. In this scenario, the projected payback time for the mirror constellation given the additional revenues from the multiple solar fields is approximately 2 years.

Enhancing terrestrial solar power using orbiting solar reflectors

“…With the advent of reusable, heavy lift launch vehicles delivering over 100 tones to Earth orbit, a constellation of such reflectors could be quickly deployed. Such reflectors could be conventional deployable structures [7,11,12], or could be fabricated in orbit to enable ultra-lightweight gossamer reflectors, thus overcoming the limits imposed by launch loads and the launch vehicle payload faring volume [31].…”

“…SSOs have typically been considered as circular orbits for solar reflector applications in the literature [12]. However, elliptical SSOs expand the catalogue of possible SSO-type reflector orbits significantly.…”

“…Other recent studies of orbiting solar reflectors by Fraas et al have also focused on applications for terrestrial solar power [11,12]. They envisage a constellation of 18 reflectors (each comprising a 10 km diameter array of individual 1 km reflectors) in a 1000 km polar orbit servicing some 40 solar power plants.…”