Source of ATP in RBC&;s is

Glycolysis is the only source of energy in erythrocytes. During anaerobic (oxygen deficient) condition, when one molecule of glucose is conveed to 2 molecules of lactate, there is a net yield of 2 molecules of ATP. 4 molecules of ATP are synthesized by the 2 substrate level phosphorylations (steps 6 and 9). But 2 molecules of ATP are used in the steps 1 and 3, hence the net yield is only 2 ATP (Table 9.4). The whole reaction is summarized as Glucose + 2 Pi + 2 ADP --> 2 Lactate + 2 ATPRef: DM Vasudevan Textbook of Medical Biochemistry, 6th edition, page no: 93 & 96