The Power of the Sun
Space-based solar power has had a slow start, but the technology may finally take off in the next few decades. Since its inception, solar power has had a severe limitation as a renewable energy: it only works when the Sun is shining. This has restricted the areas where solar panels can be effectively used to sunnier, drier regions, such as California and Arizona. And even on cloudless days, the atmosphere itself absorbs some of the energy emitted by the Sun, cutting back the efficiency of solar energy. And let's not forget that, even in the best of circumstances, Earth-bound solar panels are pointed away from the Sun half of the time, during the night.
So, for over half a decade, researchers from NASA and the Pentagon have dreamed of ways for solar panels to rise above these difficulties, and have come up with some plausible solutions. There have been several proposals for making extra-atmospheric solar panels a reality, many of which call for a spacecraft equipped with an array of mirrors to reflect sunlight into a power-conversion device. The collected energy could be beamed to Earth via a laser or microwave emitter. There are even ways to modulate the waves' energy to protect any birds or planes that might wander into the beam's path.
The energy from these space-based solar panels would not be limited by clouds, the atmosphere, or our night cycle. Additionally, because solar energy would be continuously absorbed, there would be no reason to store the energy for later use, a process which can cost up to 50 percent of the energy stored.
Proponents of this energy strategy argue that we have all the basic science necessary to design and deploy space-based solar panels, but opponents, like Tesla’s Elon Musk, counter that the upfront costs are too high. In 2012, Musk suggested to Popular Mechanics that we should “stab that thing in the heart.”
Getting off the Ground
As climate evidence continues to demonstrate, energy production has more costs to consider than simply the dollars and cents on the price tag. An efficient, renewable source of energy with a small carbon footprint and virtually no waste seems to attractive to ignore for many environmentally conscience individuals including Paul Jaffe, spacecraft engineer at the U.S. Naval Research Laboratory.
Last March, Jaffe presented his plan for implementing space-based solar at the Department of Defense's first-ever Diplomacy, Development, and Defense (D3) Innovation Summit Pitch Challenge. Out of 500 submissions, Jaffe’s plan for implementing space-based solar took home four of seven awards. Jaffe presented a plan that he said would have demo orbital power station capable of powering more than 150,000 homes in orbit within 10 years for $10 billion. Jaffe said that investment would pay off in the long run.
“Over time, things become more efficient. Wind and solar literally took decades to get competitive with carbon-based alternatives. I see similar potential here," Jaffe said in an interview to Salon. "In many ways, the future of space solar rests less on scientists and engineers, and more on people who decide what they want to pay for.”
Jeffe is not the only one who sees promise in this strategy. Both Japan and China have plans for launching their own space solar stations in the next 25 to 30 years. In the United States, the private company Solaren Corp. is raising money for a design and demonstration phase. It has already drawn some lucrative interest, having been awarded a contract with major electric utility provider PG&E.
None of these projects will see energy returns for the next decade or more, and the average energy user can only hope this will be soon enough. Last year, the U.S. Energy Information Administration projected that world energy consumption will grow by almost 50 percent between 2012 and 2040.