The prevailing energy harvester utilizes a convectional magnet that limits the output power due to the imperfect coupling of the flux linkage and the leakage of the magnetic fluxes away from the coil. Herein, a circular Halbach array magnet comprising the arc magnets is proposed as a high-performance rotational energy harvester for preventing flux leakage by concentrating the magnetic flux in a particular path. The Halbach magnet is made up of eight individual arc magnet segments that are kept apart by 1 mm to induce a fourfold increase in magnetic flux density over a conventional magnet. The proposed rotational energy harvester can deliver an exceptional 603.2 W m⁻³ power density, which is attributed to a three times increase in the power density. The harvested power is utilized to charge a 30 mAh battery for driving a complete IoT system for the development of self-powered wireless environmental monitoring systems. Furthermore, an intelligent system is designed using cutting-edge artificial intelligence (AI) technology which accounts for Mxene/P(VDF-TRFE)-based triboelectric sensor output data and considers different weather parameters to accord a high accuracy of 99% in wind speed prediction.