This is the stuff of science fiction movies which are, by the way, my favorite genre. I have been amazed over and over again how the stuff of science fiction eventually becomes scientific fact. I have always loved science and was pretty good at it in school. Now I just write about it on blogs. One scientific dream that was once science fiction is now becoming a fact and that is the collecting of the Sun’s energy in space and beaming it back to earth. This has, in fact, been an idea bounced around in the scientific world for over 40 years. But Ray Bradbury and Richard Matheson aside, this idea has now garnered interest from the US Military as well and thanks to advances in technology is close to becoming reality today.

One of the drawbacks in the development of sources for solar power is that it requires the Sun 24/7, which is just not possible from the surface of an orbiting planet. This requirement is the result of the need for electricity every day, around the clock and the drawback is that the Sun is not available all the time and even when it is, it is often reduced by clouds or rain. So how do you fill in the blanks? So that solar power becomes a viable, around the clock source of electrical power?


From: Fox News

Launch solar panels into space and beam the power back to Earth.

This idea, which seems difficult and expensive at first blush, also solves other problems related to solar power. The hottest surfaces on the planet, the desert, for instance, are never the areas where large populations reside. So in order to build big solar arrays and put them where the sun shines the hottest is to place them in areas where people are not comfortable living. The end result of this is that you’d have to send electricity many hundreds of miles to the grid over.. what? Invisible transmission lines? I don’t think so.

So these problems plague solar power and have cut into the enthusiasm that many have had for it over the years. But now there is a solution! Or at least one that they think they can make work. I know the concept sounds far-fetched and wildly impractical, hard to accomplish and super expensive. When it was first discussed, at one time by the Pentagon and space enthusiasts, back in the 1960s and 1970s, it was ridiculous. Recently, however, the idea of space-based solar power has begun to look less like science fiction and more like a technology whose time may be coming. Mostly because the Pentagon and private companies are ramping up efforts to make space-based solar power a reality.

Known as SBSP (space based solar power), the exciting plan requires beaming space-based solar power back to Earth. This involves launching a series of large satellites into space, using robotic technology to assemble the solar arrays, transmitting the energy 22,000 miles to earth using microwave technology, and then converting that energy to electricity on the ground. Whew. I get exhausted just writing about it! But the fact is, all of that is now feasible (although still pricey) thanks to technological advances in recent years. These include cheaper and more reliable launch technology, lighter and stronger materials for solar stations, significant improvements in the robotic technology needed to assemble the solar arrays, far more efficient solar cells, more precise digital devices to direct that energy accurately to earth, and significantly smaller and more powerful microwave transmitters and receivers.

As well, as recent as a year ago, engineers did a small but successful experiment in taking energy from solar cells, converting it to microwaves, and then beaming it 92 miles from Maui to the Big Island of Hawaii, where it was converted back into 20 watts worth of electricity. This provided proof that such a thing could actually be done. And then also last spring, the California-based Solaren Corporation signed a contract with Pacific Gas & Electric (PG&E) to provide 200 megawatts of power – about half the output of an average coal-fired power plant – by 2016 by launching solar arrays into space. I realize this is small and doesn’t seem immediately useful to millions when the planned output is so tiny and the span of time so great but it is a promising start. It proves at last that such a process is possible. To the credit of this great idea, several other companies have announced their intentions to put up solar satellites of their own.

But the big question still looms. Can this feat be accomplished at a price competitive with terrestrial solar power? So far, the Pentagon’s estimate of what it will cost – $10 billion to put a 10-megawatt experimental solar station in orbit by 2016 – is five times higher than Solaren’s and would produce far less power. There is no way this would ever be feasible for powering small plants or residential properties but it has promise for large scale operations and for military use. In fact, of the factors driving the renewed interest in space-based solar power are the current push to cut greenhouse-gas emissions and a growing interest from the military. But the truth is none of this interest or even the strongest desire will make a wit of difference if the cost is outrageous.

Back in 1968 this concept was first offered by Peter Glaser, an engineer in 1968. He worked with the consulting firm Arthur D Little on space related projects. He was excited by the solar cells and microwave transmitters that had come into existence during that time as well as the winding down of the Apollo program, leaving NASA eager to start new research for interesting projects. One of those projects, launching “space habitats” evolved into our current Space Shuttle program which allows people to actually live and work in space. With people on the Space Station there was and still is a desire to have them build solar powered satellites.

But the whole idea was scrapped back them because it was logistically difficult because the Satellites themselves would make the Space Shuttle look like a toy and they had not yet developed the robotic arms they use today and such an idea seemed impossible. If they had gone forward with it back then the cost would have been astronomical. Something like a trillion dollars, I kid you not, just to get the first kilowatt of power! And overall, it would have taken 20 years.. and it was not worth it. It is still very pricey today even with our new developments.

The up side is that, at 22,000 miles up in the atmosphere, a geostationary satellite is in full sunlight virtually all the time. So the idea never really went away. In fact, as early as the mid-1990s, NASA did revisit the concept. At that time a team of engineers was assembled to see whether advances in technology made space-based solar power more feasible. It was at this time that the idea first appeared to be doable. Especially today, with the new information regarding climate change and other factors that require we use less oil and coal. One popular notion is energy independence. So the desire to reduce carbon emissions combined with the desire to create our own energy sources, this idea has taken on new momentum.

And as far as the cost, it is almost inevitable that carbon emissions will end up being taxed one way or another, and when they are, renewables like SBSP will immediately become more competitive economically. It will be a matter of whether industry will wish to continue cranking it’s engines on the old gas at a higher tax expense or make the switch to solar at a similar price. And this is what motivates companies like Solaren and PG&E. Although they are unwilling to reveal the details of their very secret research, Solaren has said publicly that it will cost roughly $2 billion to launch a handful of satellites carrying the equipment that will be robotically assembled into a single, large solar station. That’s a big hunk of cash but it’s actually very little when you consider that America spends almost as much a day on our wars.

One way the company plans to boost efficiency is to use parabolic reflectors to concentrate sunlight onto the solar cells. The biggest expense will be getting the equipment into space but if they can lower the overall weight of that equipment they can reduce the overall number of launches and, hence, the overall cost. Solaren has big plans for this medium, with a desire to put satellites into orbit that can generate enough electricity for 1 million homes. Their “rectanna” will consist of an array of smaller antennas that will cover about a square kilometer – far less real estate than you’d need if you were using ground-based solar cells to gather an equivalent amount of power. And because Solaren’s satellite will be in geostationary orbit, the antennas won’t have to track it across the sky. Just like a satellite TV receiver, they’ll always aim at a fixed point in the sky.

The microwaves are spread out over a square kilometer and this means that they’d be relatively harmless to creatures like a flock of birds that might fly through them. And if the beam should wander, the satellite will be programmed to scatter it. Pretty cool stuff, no? Writing this I feel like I’m writing a segment for Star Trek. It really does feel a lot like science fiction.

Solaren isn’t the only company trying to commercialize SBSP. PowerSat an Space Energy are fast on the track. PowerSat is based in Everett, Wash. and has recently filed patents for its own space-power system, which will use an array of hundreds of small satellites linked together rather than a single large one. PowerSat also claims it can reduce some of the high costs of putting the technology in space by using solar energy to power electronic thrusters to maneuver the satellites into orbit. Sort of a double solar benefit, I guess. And Space Energy, which is a Swiss company, is also working on SBSP. Solaren is the only one, though, with a contract with a brick and mortar utility. This is an important advancement because it has always been thought that Solar Energy is a hard sell and so expensive it could be a no sell at all.

But consumer interest is there these days, with fears of global warming and concern over the environment. Where there is money, there is a will. And, of course, with interest from the military, SBSP could give a major boost to the technology. First and foremost, the military is interested in energy security and this concept offers that. They are also interested in getting off fossil fuels because climate change could pose national security risks. But there would also be a tactical advantage to space-based solar when you consider that the military uses diesel generators to supply their bases with power in remote regions such as Iraq, Afghanistan and in undeveloped countries as well. They end up having a significant footprint getting energy in to these remote places with frequent convoys of oil tankers, the soldiers needed to protect them, and air support. This all adds to the overall expense and danger of using oil. A solar solution would fix all of that.

Consider also what a fantastic effect this technology would have on disaster response. There would be no need to move tankers, trucks, boats or aircraft over destroyed land areas after hurricanes or earthquakes just to get energy to the people saving lives. Such huge benefits has fueled government interest in this technology as well as interest from the private sector and the military. NASA is particularly entangled in the research, development and future use of SBSP. By undertaking some of the research and being an early customer for SBSP, the government could rapidly accelerate development of the technology. And this sort of investment both of money and of time is necessary to get this done.

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