There is some renewed interest on my part in wind and related non conventional energy. Thanks to a brother of a friend whom I met last month only, I know a bit more about wind mills and the economy around it.
One thing that has come around is that its a entrepreneurial venture best suited for someone who has relatively deeper pockets. Relating to the sheer volatility and the size of investment required for this business, it becomes a hard to get for a normal first generation entrepreneur.
For example, in India, a typical windmill costs around 1.5 crores to set up. Though government provides decent subsidy on taxes and depreciation benefits to make it relatively viable, you still need about 25-30% of the initial investment to be put in. Further, the amount financed by banks needs a separate kind of guarantee, just because the asset is relatively immovable. You know, they cant just get the windmill out of its root and sell it to claim their money, in case the business defaults on the loan.
Further than that, there are open questions on the stability of the returns from the windmill. Though there are devices measuring the wind speed and therein judge the potential of a place to produce wind energy. These devices are put in place by a govt body and data is recorded to be sold to the companies in the business for generating wind energy.
However, there is no certainty that this data will come around. Remember, its a huge investment going to be based on the data produced by these measuring devices.
Some basic economics around windmills in india are found here -