Decision making under the situation of certain parameters for each factor is easy. However in real world, due to the complexity which arises from uncertainty, decision making is really difficult. So when managers are about to making investment decisions, they should be aware of uncertainty and act according to it. Most used techniques for analyzing and evaluating investments is capital budgeting criteria. In this paper, in order to take uncertainty into account, capital budgeting criteria is studied using fuzzy cash flows and discount rates. Later, two wind farm projects thought to be established in two different locations in Turkey are analyzed and evaluated according to both crisp and fuzzy capital budgeting techniques.