Energy efficiency is emerging as a key concern in sustainable software engineering, yet little is known about how modern frontend frameworks differ in their energy consumption. While performance comparisons of Angular and React are well documented, their environmental impact remains unexplored. This paper presents an empirical study comparing the energy consumption of equivalent applications implemented in Angular and React under controlled execution scenarios. Using the Firefox Power Profiler and automated execution scenarios, we measure energy consumption across multiple workloads. Results show that Angular consumes 21.66% less energy on average than React. Our findings highlight the importance of considering energy efficiency when selecting frontend technologies.