what are some disadvantages of using energy generated by wind?

Mainly cost and reliability. Cost could come down with further use and technological innovation. Can’t improve on the reliability, though, and that will always keep wind power as only a partial solution to the world’s needs.

Think of it, as we use more and more wind power, that means more and more the risk that we might need power when it’s not available (no wind that day). That greatly increases the instability of the power system. Estimates in Ontario, Canada, recently suggested switching to more wind power would have to be limited to something like 20% of total output. Some locals would be able to use higher ratios, but nobody would be able to use 100% except in very small areas backed up as part of very large, massively redundant (read overbuilt) distribution systems to bring in power from elsewhere when needed.

Wind power also is noisy and takes up large areas (some other disadvantages)