a scale of cost is used.
wind power and solar power have lower variable costs(operating cost) but higher fixed costs(plant cost) than fossil fuel plants.
The only variable cost of wind power is maintenance (lubrication etc) and management, which is a very minor cost.
cost of a wind power plant of about 1mw is roughly 10-15crore. For the same money, you can buy roughly 10mw worth of diesel plants.
Cost of around 100kw wind plant is roughly 1.5-2crore. Where as the same in diesel cost about 25lacs.
So cost of wind power plant increases alot more compared to diesel plants as size decreases.
How ever after the 1-1.5mw range the cost of wind power remains relatively constant due to the fact that a wind power plant consists of individual 1-1.5mw turbines. Where as diesel or other fuel plant price per mw falls alot.
This means that apart from energy companies, wind power is feasible for private companies with a power requirement of over 1 megawatt and a bank balance of over 15 crore.
Also, capsat didn't mention that there are areas inland as well with good amount of wind available. These areas can be developed into industrial zones so factories can shift their facilities to such areas and use wind to power their businesses...
As far as solar power is concerned, photo-voltaic cells are not yet cheap enough for countries like ours to utilize at a large scale. The only feasible solar power is solar thermal energy. Same could be utilized at a household level for water filtration..