Wind power has become cheaper and more widespread than most other renewable energy sources. The strong growth in wind power capacity is attributable to the promotion of models of renewable energy sources, energy supply security, fuel diversity concerns, ecological awareness and economic reasons. But with growing scale, investments need to be made more carefully to be successful. The employment and development of renewable energy projects will depend on how they are valued and risk-assessed accurately. This paper proposes a cost benefit model for the wind energy project investment and calculates risk using Value-at-Risk (VaR).