Renewable energy sources, especially wind energy, are widely applied as a mean to reach emission reduction with the increasing concern of environmental protection. Although wind generation does not produce harmful emissions, its effect on the thermal generation dispatch can actually cause an increase of emissions, especially during low or medium power demand periods of a day. A multi-objective energy dispatch that considers environment and fuel cost under large wind energy is proposed. An efficient encoding/decoding scheme that could effectively prevent unviable solutions during the application of stochastic search methods is applied; thereby dramatically improving search efficiency and solution quality. The non-linear characteristics of power generators, and their operational constraints, such as generation limitations, ramp rate limits, prohibited operating zones, and transmission loss, could be considered for practical operation. The effectiveness and feasibility of the proposed approach are demonstrated by a TAI-POWER and IEEE 30-bus test systems study. The experiment shows encouraging results, suggesting that the proposed approach is capable of providing higher quality and a wider range of Pareto-optimal solutions so that the decision makers can have a more flexible and reasonable choice. (c) 2010 Elsevier Ltd. All rights reserved.