In a recent publication, Chen et al. (2011) [1] studied the thermogravimetric behavior of the combustion of the microalgae Chlorella vulgaris and described a kinetic analysis based on Kissinger-Akahira-Sunose (KAS) and Flynn-Wall-Ozawa (FWO) methods in the work entitled: "Thermogravimetric analysis of microalgae combustion under different oxygen supply concentrations" (Appl. Energy 88 (2011) 3189-3196). Some comments about this work are discussed in the present letter to the editor. (c) 2011 Elsevier Ltd. All rights reserved.