AlNiCo magnets, an alloy primarily composed of aluminum (Al), nickel (Ni), and cobalt (Co), have been a cornerstone in the energy sector for decades. Renowned for their exceptional thermal stability, high coercivity, and resistance to demagnetization, these magnets have found critical applications in renewable energy systems, conventional power generation, and advanced energy storage technologies. Despite the rise of rare-earth magnets like neodymium-iron-boron (NdFeB), AlNiCo magnets remain indispensable in scenarios demanding reliability under extreme conditions. This article explores their multifaceted roles in the energy sector, highlighting their technical advantages, historical significance, and evolving applications.