Alkali Metal Thermo Electric Convertor (AMTEC) uses infrared radiation to knock out electrons from some alkali metal acting as the working material. In the present paper sodium is chosen as the alkali metal. The freed electrons after going through a circuit and having done the prescribed work meet the sodium ions. A solid electrolyte, called beta" alumina solid electrolyte (BASE) is used for diffusing the working material ions. The system is closed and continues working as long as the heat source is kept turned on. The longevity, power and efficiency of the device depend inversely to some extent on the thickness of the electrolyte and electrodes. In this work we have optimized the thickness of electrodes. This optimization improved the efficiency and power output by 28 and 14.8% points respectively. (C) 2014 Elsevier B.V. All rights reserved.