Due to nonlinear I-V characteristics of photovoltaic cells, an maximum power point tracking algorithm is adopted to maximize the output power. In this paper, an approach for peak power tracking using the sliding mode control is proposed. The proposed controller is robust to environment changes and load variations. The stability and robustness of the controller are addressed. The performance of the controller is verified through simulations and experiments. It demonstrated that the proposed approach can be implemented effectively and economically. (C) 2009 Elsevier Ltd. All rights reserved.