And here is number 6 and it is surely less risky:
http://pesn.com/2005/08/02/9600142_IAUS_Solar/
Hello,
They are using a type of turbine I happen to know quite well, but not many others know about it.
It has outstanding efficiency, but it wants to be used and built the right way. It's a bit finicky.
The basics of that kind of turbine got patented over a 100 times.
Re solar I came across something that even outdoes their claims so I don't bother to check this one and check the better one as soon as I get around to do it.