posted by Andrew Holland on October 5, 2011 at 5:42 pm
I want to talk briefly about a next-generation proposal for energy generation that may sounds outrageous at first: Space Based Solar Power (SBSP). Essentially, SBSP is simply launching solar panels into space (specifically in an equatorial Geosynchronous Earth Orbit) and beaming the energy to the earth using harmless microwaves.
The concept was first proposed by US space expert Peter Glaser in 1968. Since then, major US reports have been published in 1997 and 2007 that show the viability of SBSP. The National Space Society has an impressive library of the reports that have been done on this issue.
It is estimated that a solar power station in orbit could harness five times the solar energy captured by stations on the ground because of atmospheric interference and the fact that satellites in GEO do not pass into night. A satellite in Geosynchronous orbit receives 5-15 times as much solar energy per year as any place on earth.
So, SBSP relies on three key technologies: solar photovoltaic cells to create electricity from sunlight, microwaves to beam the energy to earth, and rocket technology. These technologies exist today: solar cells are becoming common, the technology to beam energy to earth is essentially the same as the radars in the nose of a fighter plane, and we have been launching satellites for over 50 years. The problem, of course, is cost. Mostly, the problem is that the cost of launching satellites is too high for this to be competitive. The reason for that cost disparity is that America’s launch systems (rockets) are used so seldom that we are unable to achieve the economies of scale that would inevitably result from a greater demand for launch vehicles.
Although this sounds like Star Trek, it is real, and uses technology that already exists. PG&E, the California-based utility, has entered into a deal to purchase electricity from a startup – Solaren – that will harvest energy from space.
Japan, China, India, and Russia are taking preparing space-based solar programs. India – who has begun a significant investment into a ‘solar mission’ – has expressed interest in partnering with the United States on a SBSP program. If the United States doesn’t lead on this, other countries will.
SBSP could be a future source of baseload power, but for now its major advantage is that it can provide energy on demand anywhere in the world. Remote power should be an obvious benefit to a military looking to power a base in a remote location. This could reduce or eliminate the need to truck-in fuel, which, as I mentioned yesterday, is a major threat to the U.S. military.
Other potential customers would be remote energy exploration – like shale or Arctic exploration – that is far from any electric grid.
A power plant in orbit would be an important way to change our paradigm in space from the choice that NASA faces of either scientific research or human exploration. The truth is that both of these are dead-ends. In an era of reduced budgets, it is very difficult to justify expenditures. However, a commercial paradigm in space would mean that we are trying to use some of the vast, unfiltered solar energy that passes by the earth every day for profit and human gain. With such a profit motive, there would be a real reason to set-up an infrastructure for repeated launches and a permanent space presence.
SBSP needs start-up capital, but ultimately, this may be something that is better handled by the private sector than NASA. There is money to be made, and the company that proves it will have a significant advantage.