One of the primary drawbacks to using solar energy as a source of electricity is the unreliability of the harvesting process. The intensity of the sun varies from place to place and from one season to the other in the same place on earth. Also, there is the obvious drawback that the sun is not accessible 24 hours a day when harvesting the solar power from an earth-based location.
For over 40 years there have been studies performed to determine the feasibility of developing space solar power (SSP). A recent study group with the backing of the International Academy of Astronautics has completed a 3 year assessment of using Solar Power Satellites (SPS) to harvest sunlight in space and then deliver it via wireless power transmission to Earth.
The actual goals of this particular study were to determine the role SSP might play in meeting the increasing need for sustainable energy in high quantities over the next century, to assess the readiness and risks associated with the SSP concept and then attempt to frame a roadmap that might help to realize the concept.
What the study concluded was that while the concept of space solar power is technically feasible it will only become economically possible when the technology has been properly developed and matured. It will also only be possible with a significant international consortium prepared to inject considerable funding into the project. The potential figures that may be needed were not actually suggested in the study.
The ability to access the sun 24 hours a day would be a matter of setting up a series of satellites that are sent into specific orbits designed with the specific job of harvesting the sun’s rays. The idea that solar energy is only a part-time energy solution would be overcome turning it into a more reliable and consistent source of energy. It would be assumed that the technological advancements that were achieved to reach the point that this concept could become a reality would also mean that earth-based solar energy solutions will have been vastly improved as well.
Possible advantages for establishing a space based solar power system include:
- The ability to scale the network of power satellites as needed
- The access to solar power is constant 24 hours a day.
- The payback time would be shorter than other solar power methods because of the constant feed of energy.
- Construction of the satellites is a known factor that has already been achieved.
- The materials used to construct the satellites are far lighter than earth-bound equivalents.
To read the final report of the IAA study it its entirety (it’s a 249 page document) you can find the full text here.