Wind power generation is becoming increasingly common in the portfolio mix of many utilities around the world. Wind turbines are presently available up to 5MW. Smaller turbines may be installed for individual customers and connected to the grid at the distribution level, and larger units are typically combined in a wind “farms” connected to bulk power systems at the transmission level. Turbines ranging from 1 to 3MW are very commonly used in on-shore wind farms and larger units become more practical when installed off-shore. This paper will focus on the procedures used in designing a large scale wind farm and the methods to estimate the expected energy generated.