Corrosion of mild steel in acidic environments poses a significant challenge to energy intensive industrial processes, as it accelerates material degradation and contributes to increased energy consumption through higher fluid friction, pressure losses, heat transfer inefficiency, and frequent maintenance requirements. In this work, the corrosion inhibition performance of 1 (furan 2 yl) 2 phenylethanol (FPE) for mild steel in 1.0 M hydrochloric acid was systematically investigated, with particular emphasis on interfacial protection and its implications for energy efficiency during industrial acid cleaning operations. Potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS) techniques revealed that FPE behaves as a mixed type corrosion inhibitor, predominantly suppressing the anodic dissolution of iron. The inhibition efficiency increased with inhibitor concentration, reaching a maximum of 95.3% at 5.0 × 10⁻⁴ M at 298 K. EIS results showed a pronounced increase in charge transfer resistance and a corresponding decrease in double layer capacitance, confirming the formation of a compact and adherent protective film on the mild steel surface. Adsorption studies indicated that the adsorption of FPE molecules follows the Langmuir adsorption isotherm, suggesting monolayer adsorption with strong interfacial interactions. Density Functional Theory (DFT) calculations supported the experimental findings by demonstrating that the π electron systems of the furan and phenyl rings, along with the oxygen atom of the hydroxyl group, act as effective adsorption centers, facilitating electron donation to surface iron atoms. By mitigating electrochemical corrosion reactions and preserving surface integrity, FPE indirectly contributes to reduced energy losses and improved operational efficiency. These results identify FPE as an efficient and environmentally compatible corrosion inhibitor suitable for energy conscious industrial applications in acidic media.