In this paper, an environmental economic dispatch problem with storage, network, and inter-temporal constraints is considered. An approach based on the simultaneousperturbation technique is proposed to deal with the equality and inequality constraints in the economic dispatch problem. The algorithm has been implemented using Matlab and tested on a 6-bus, 5-generator system and a 140-bus, 48-generator system. The effects of cap-and-trade policies, energy storage, and transmission line flow limits in economic dispatch are discussed. The simulations reveal that the method can handle a variety of constraints with good convergence performance.