<![CDATA[Conceptual understanding is one of the essential competencies that students must develop in physics learning, particularly in renewable energy topics, which involve various phenomena and their applications in everyday life. However, students’ conceptual understanding is often not optimal due to their limited engagement during the learning process. This study aimed to determine the difference in students’ conceptual understanding between those taught using the Complex Instruction (CI) learning model and those taught through conventional learning on the topic of renewable energy at SMA Negeri 2 Pekanbaru. This research employed a quasi-experimental method with a Posttest-Only Control Group Design. The research sample consisted of Class X.1 as the experimental group, which was taught using the Complex Instruction learning model, and Class X.4 as the control group, which received conventional instruction. The research instrument was a conceptual understanding test developed based on three indicators: translation, interpretation, and extrapolation. Data were analyzed using normality tests, homogeneity tests, and the Independent Sample t-Test. The results showed that the average conceptual understanding score of students in the experimental class was 86.81, categorized as Very Good, while the control class achieved an average score of 78.81, categorized as Good. The hypothesis testing result revealed a significance value of 0.001 < 0.05, indicating a significant difference in conceptual understanding between the experimental and control groups. These findings demonstrate that the Complex Instruction (CI) learning model is effective in improving students’ conceptual understanding of renewable energy. The model provides students with opportunities to actively participate through heterogeneous group work, role assignments, discussions, and the completion of complex tasks, thereby helping them construct a deeper and more meaningful understanding of concepts.]]>
