Access
This article is part of Nature's premium content.
Published online 16 September 2008 | Nature | doi:10.1038/news.2008.1109
News
Beaming energy from space
A small step towards a very grand vision
The idea that Earth's energy needs might be met by giant arrays of orbiting solar panels has been around since the 1960s1. As president of the Space Power Association, an international organization focused on this visionary scheme, John Mankins has long experience of the scepticism it engenders.
To read this story in full you will need to login or make a payment (see right).
Comments
Reader comments are usually moderated after posting. If you find something offensive or inappropriate, you can speed this process by clicking 'Report this comment' (or, if that doesn't work for you, email webadmin@nature.com). For more controversial topics, we reserve the right to moderate before comments are published.
How many decades are required for a 10 megawatt orbital energy system to pay back at ground level the energy required to manufacture, emplace, and maintain it? China adds 1000 megawatts of coal-fired electrial generation capacity every week.
This is a very interesting concept that is obviously generations down the line. I think this is leading us in the right direction for long term renewable energy solutions. Also, comparing it to China's fossil-fuel based capacity is just silly because expanding an already well developed non-renewable resource is not anything special.
What about this "space elevator" I've been hearing about? If just one of these elevators could be built, we could haul the materials for these power collectors up and down all day for a very small fraction of the cost of sending an equal amount of mass into space with a rocket engine (after the elevator is built, that is. The elevator might be pretty expensive, but well worth it.) With a space elevator, I think we could have lots of these collectors (as well as anything else you can think of) in space in relatively little time. It's like any resource here on earth: If you want to get to it, you have to build a road to it first. Just my layman's opinion.
Lifting the mass from Earth to construct orbiting power satellites is not the economically preferable strategy, as Gerard O'Neill and the Space Studies Institute established 25+ years ago. The better option is to use mined lunar regolith propelled into orbit through a mass-driver launch facility, with the raw material then captured and refined with a rather simple solar-powered furnace. Once the refined material is cast and machined into the structural shapes required for the collection array, the finished components can then be moved with tugs (using either chemical- or ion-powered rocket motors) to the construction orbit for assembly. The technology and materials to accomplish a lunar-based source of construction material under that concept is largely within humankind's current capabilities. Although a very good idea, the technology and materials necessary to construct a space elevator are not yet within our current capability and probably won't be for some time.
It is better to build buildings with windows for natural light.
"Earth's atmosphere absorbs or scatters half of the Sun's rays". That means that putting the system in orbit must have a cost, capital and operating, of less than twice the equivalent ground base photo-voltaic system. The economics of this don't look very good, now or ever!
. I think that ALL scientific magazines/websites (like Nature) should DEBUNK all FOOLISH and NONSENSE projects like the HOAX/ILLUSION "Space Solar Power" URBAN LEGEND!!! However, I've DEBUNKED it in this article: http://www.ghostnasa.com/posts/038sspdebunked.html .
There is a parallel universe where grown-ups use elementary physics, economics, and arithmetic to test their logic. The fact that this article represents a different universe is no reason to dismiss space solar power.