In an effort to identify suitable microalgal species for biodiesel production, seven species were isolated from various habitats and their growth characteristics were compared. The results demonstrated that a green alga Scenedesmus obliquus could grow more rapidly and synthesize more lipids than other six microalgal strains. S. obliquus grew well both indoors and outdoors, and reached higher mu(max) indoors than that outdoors. However, the cells achieved higher dry weight (4.36 g L-1), lipid content (49.6%) and productivity (183 mg L-1 day(-1)) outdoors than in indoor cultures. During the 61 days semi-continuous cultivation outdoors, high biomass productivities (450-550 mg L-1 day(-1)) and mu(max) (1.05-1.44 day(-1)) were obtained. The cells could also achieve high lipid productivities (151-193 mg L-1 day(-1)). These results indicated that S. obliquus was promising for lipids production in semi-continuous cultivation outdoors. (c) 2014 Elsevier Ltd. All rights reserved.