This paper presents a new optimization technique based on a multiple tabu search algorithm (NITS) to solve the dynamic economic dispatch (ED) problem with generator constraints. In the constrained dynamic ED problem, the load demand and spinning reserve capacity as well as some practical operation constraints of generators, such as ramp rate limits and prohibited operating zone are taken into consideration. The NITS algorithm introduces additional mechanisms such as initialization, adaptive searches, multiple searches, crossover and restarting process. To show its efficiency, the NITS algorithm is applied to solve constrained dynamic ED problems of power systems with 6 and 15 units. The results obtained from the NITS algorithm are compared to those achieved from the conventional approaches, such as simulated annealing (SA), genetic algorithm (GA), tabu search (TS) algorithm and particle swarm optimization (PSO). The experimental results show that the proposed NITS algorithm approaches is able to obtain higher quality solutions efficiently and with less computational time than the conventional approaches. (c) 2007 Elsevier Ltd. All rights reserved.