International Journal of Scientific Engineering and Science Volume 9, Issue 5, pp. 210-215, 2025. ISSN (Online): 2456-7361 210 http://ijses.com/ All rights reserved A Comparative Study on the Performance of Single- Stage and Cascade Thermoelectric Refrigerators Djuanda 1 , Muhsin Z. 2 , Erniyani 3 , Otniel M. Sariri 4 1,2,3,4 Mechanical Engineering Education, State University of Makassar, Makassar, Indonesia Correspondent author: djuanda@unm.ac.id Abstract— This study aims to compare the performance of thermoelectric modules in terms of their coefficient of performance (COP) betwe en single-stage and cascade configurations. A quantitative approach was employed using an experimental research design. Each configuration was tested under voltage variations of 3V, 6V, 9V, and 12V. Data were collected using a data acquisition system. The experime nts were conducted at the Mechanical Engineering Education Laboratory, Faculty of Engineering, Makassar State University. The single-stage thermoelectric module was tested four times at voltage levels of 3V, 6V, 9V, and 12V. The results indicated that the highest COP for the single- stage configuration was 3.64 at 3V, followed by 1.43 at 6V, 0.72 at 9V, and 0.45 at 12V. Similarly, the cascade thermoelectric module was tested at the same voltage levels. The corresponding COP values were 1.87 at 3V, 0.64 at 6V, 0.22 at 9V, and 0.073 at 12V. Ba sed on the experimental results and data analysis, it can be concluded that the single-stage thermoelectric module exhibits a higher COP compared to the cascade configuration under the tested conditions. Keywords—Thermoelectric, single-stage, cascade-stage, coefficient of performance . I. INTRODUCTION The rapid advancement of technology in the field of alternative energy necessitates that technicians continually enhance their knowledge and skills to avoid being left behind amidst fast-paced technological progress (Sumarjo Jojo, 2017). In line with these developments, innovation is essential to support and drive practical applications in daily life, which begins with the generation of ideas prior to implementation (Simamora, 2019). Cooling systems, in particular, require continuous innovation and development to improve efficiency, practicality, and environmental sustainability. A cooling machine is a system designed to produce low temperatures by transferring heat from within an insulated space to the external environment, thereby lowering the internal temperature relative to its surroundings. Common examples of cooling devices include refrigerators, freezers, and air conditioners (AC). The fundamental working principle of these machines is evaporation, where a refrigerant absorbs heat and undergoes phase change, leading to a cooling effect. During this process, heat from the surrounding air is absorbed and transferred, resulting in reduced temperatures (Ryanuargo, 2013). Cooling systems are widely used in commercial buildings, offices, and households. Among them, AC units not only provide cool air but also regulate humidity for human comfort. Similarly, refrigerators are used to preserve food, cool beverages, and perform other essential functions. Currently, many cooling machines—particularly those designed for food and beverage storage—remain relatively large and heavy, even in their portable versions. This bulkiness poses a challenge for mobility due to the size and weight of the components involved. Furthermore, some conventional cooling machines still utilize refrigerants containing chlorofluorocarbons (CFCs), which are harmful to the ozone layer. These systems also typically consume large amounts of electrical energy, making them less energy efficient and environmentally sustainable. As a result, there is a growing need for cooling technologies that are cost- effective, energy-efficient, and eco-friendly. One promising solution is the thermoelectric cooling system (Mirmanto, 2018). Thermoelectric coolers represent an innovative technology that converts electrical energy into a temperature gradient, enabling cooling without the use of traditional refrigerants. When supplied with a DC voltage of approximately 12–15 volts, one side of a thermoelectric module becomes hot while the other becomes cold (Amrullah et al., 2015). This method of cooling is environmentally friendly, durable, easy to maintain, and suitable for both large-scale and portable applications (Mirmanto, 2018). Thermoelectric modules can be configured in series (multi- array) to enhance performance. Due to their dual-side nature— producing heat on one side and cold on the other—these modules can be arranged in a cascade or multi-stage configuration, where the cold side of one module is used to cool the hot side of another. This setup is particularly effective in applications such as water-cooling systems or portable cool boxes that utilize thermoelectric elements. Based on these considerations, this study aims to compare the performance of single-array and multi-array thermoelectric cooling systems in terms of efficiency and effectiveness. Thermoelectric devices function as tools for the direct conversion of thermal energy into electrical energy—known as thermoelectric generators (TEGs)—or, conversely, for converting electrical energy into a temperature gradient— referred to as thermoelectric coolers (TECs). These devices operate based on the Seebeck effect, which was first discovered by Thomas Johann Seebeck in 1821. The Seebeck effect states that when two dissimilar conductors or semiconductors are joined at two junctions maintained at different temperatures, a voltage is generated, causing an electric current to flow in a closed circuit. The magnitude of