Leonardo Journal of Sciences ISSN 1583-0233 Issue 22, January-June 2013 p. 49-64 49 http://lejpt.academicdirect.org Different Versions of Harmony Search Algorithm to Solve Dynamic Economic-Environmental Dispatch Abderrahim BELMADANI 1 , Lahouaria BENASLA 2* and Mustapha RAHLI 2 1 Department of Computer Science U.S.T.O, B.P 1505, Oran El M’naouar, Oran, Algeria. 2 Department of Electrical Engineering,U.S.T.O, B.P 1505, Oran El M’naouar, Oran, Algeria. E-mail(s): jbenasla@yahoo.fr; belmadan@univ-usto.dz; rahlim@yahoo.fr Abstract This paper presents an application of different versions of Harmony Search algorithm (Harmony Search Algorithm (HSA), Improved Harmony Search Algorithm (IHSA), Global Harmony Search Algorithm (GHSA) and Fast Harmony Search algorithm (FHSA)) to solve the Dynamic Economic- Environmental Dispatch (DEED) problem under some equality and inequality constraints. The equality constraints reflect a real power balance, and the inequality constraint reflects the limits of real generation. The voltage levels and security are assumed to be constant. Dynamic Economic-Environmental Dispatch problem is obtained by considering both the economy and emission objectives. This bi-objective problem is converted into a single objective function using a price penalty factor. In this paper different versions of HSA are tested on six generators system and its results are compared with the previously published solutions. The results are quite encouraging and useful in the economic emission environment. Keywords Dynamic Economic-Environmental Dispatch (DEED); Pollution Emission; Fuel cost; Harmony Search Algorithm (HSA); Improved Harmony Search Algorithm (IHS); Global Harmony Search Algorithm (GHSA); Fast Harmony Search Algorithm (FHSA).