Acoustic monitoring is crucial for assessing the impact of renewable energy projects on biodiversity. However, commonly used Micro Electro Mechanical System (MEMS) microphones are susceptible to electromagnetic interference and ambient noise, which degrades the quality of recordings. This study compared the performance of a MEMS microphone with an electret microphone using bird songs from Monfragüe National Park and metrics such as signal-to-noise ratio (SNR), total harmonic distortion (THD) and acoustic diversity index (ADI). The results revealed that the electret microphones outperformed MEMS in noise reduction, signal clarity and sensitivity, providing higher quality recordings that benefit artificial intelligence analysis for accurate species detection. This improvement is critical for more precise assessments of the environmental impact of renewable energy projects and for informed decision-making in the sustainable management of these infrastructures. These findings support the integration of electret-based systems into large-scale acoustic monitoring networks and the development of long-term biodiversity databases, strengthening the role of bioacoustics in conservation strategies aligned with renewable energy expansion.