Security-Constrained Unit Commitment (SCUC) is one of the most significant problems in secure and optimal operation of modern electricity markets. New sources of uncertainties such as wind speed volatility and price-sensitive loads impose additional challenges to this large-scale proble This paper proposes a new Stochastic SCUC using point estimation method to model the power system uncertainties more efficiently. Conventional scenario-based Stochastic SCUC approaches consider the Mont Carlo method; which presents additional computational burdens to this large-scale problem. In this paper we use point estimation instead of scenario generating to detract computational burdens of the problem. The proposed approach is implemented on a six-bus system and on a modified IEEE 118-bus system with 94 uncertain variables. The efficacy of proposed algorithm is confirmed, especially in the last case with notable reduction in computational burden without considerable loss of precision