Water, a crucial input in agricultural production, is distributed based on geographical and topographical patterns. However, anthropogenic climate change has intensified water scarcity in semi-arid regions. This research aims to precisely estimate crop evapotranspiration (ET) and examine the diurnal and seasonal patterns of surface energy fluxes in maize (Zea mays) crops cultivated in a semi-arid region. The precision of our methodology is underscored by the use of a large-aperture scintillometer (LAS), which measured surface energy fluxes at 5-min intervals over two crop-growing seasons. The results, a testament to the accuracy of the LAS, indicated that during the rainy (Kharif) season of 2015-2016, the seasonal sensible heat flux (H) and latent heat flux (LE) values were 185.91 and 242.14 mm, respectively. In the rainy (Kharif) season of 2017-2018, these values were 151.57 mm for H and 373.63 mm for LE. LE values ranged from 0.40 to 6.83 MJ m-2 day-1 throughout the growing season. The findings, which highlight the LAS's ability to accurately estimate surface energy fluxes, provide a deeper understanding of their interactions with microclimatic factors, such as weather, soil, and crop management. These insights, with their significant implications for ecophysiological studies and improving agricultural practices in semi-arid regions, underscore the importance of our research.