I've read about this for a long time, didn't find it that interesting, but with the recent setback on nuclear power with the Fukushima Daiichi crisis, I think this warrants a strong second look:
Will Space-Based Solar Power Finally See the Light of Day?: Scientific American
Space-based solar power offers huge advantages:
- No greenhouse gas emissions
- Very little negative impact to the environment
- Solar heat is 5 to 10 times more intense in space, and can generate power 24/7 if the solar power satellite is in geostationary orbit.
- Highly flexible and maneuverable; with wireless power transmission, you can simply redirect energy transmission to another ground based receiver if needed. This is something that the military loves, as it is constantly challenged with protecting fuel supply lines.
Some challenges remain however:
- Launch costs for these satellites are going to be immense, not to mention that it will contribute to more greenhouse gas emissions (rocket launches, etc.). This can be rectified however if we somehow are willing to go back to the moon, stay there permanently (build a moon base) and get the raw materials there instead. Given the moon's low gravity, launch costs are going to be much lower there.
- It is still uncertain on how much energy will be lost during wireless transmission. Microwave transmission is the most favorable from what I heard, but we have yet to test it in the real world. Someone needs to really send a prototype to space so that we can find out for sure.
- Solar panel technology, while having been improved over the past few decades, still is quite expensive, not to mention fragile. For example, how do we protect these solar panels from micrometeoroid impacts? What about the space junk problem?
Someone has to foot the bill. Badly. We will be facing an energy crisis soon, and I think this technology deserves a good second look.