They aren't all as much of a con as people make out. Wind turbines account for 4% of global energy production, which is a pretty decent amount, and about 9% of the UK's total for a year (and, on occasion, has even generated 20% of the electricty we needed in a single day). It's not a con, so long as it's stressed that wind power forms only a part of the future energy provision the world needs. I think that "Only a part" is often missing or under-stressed when it's discussed.