This paper scrutinizes and goes beyond previously published results on the analysis of the energy flow during friction stir welding/processing (FSW/P). An in-depth scientific method was used to assess the individual energetic contribution arising from the main components within the FSW/P system. This investigation was performed during FSW/P of AA7075 with different tool rotations and travel speeds. The main contributors to energy losses during the FSW/P process include the FSW/P tool, anvil, unprocessed base material, and the surrounding environment. It was found that only about 25 % of the total energy is effectively used to perform the welding/processing, while the remaining energy dissipates through heat into the tooling and clamping system. Additionally, around 6 % of the energy is lost towards the base material, forming the heat-affected zone (HAZ). These results suggest that proper selection of the anvil material offers a promising opportunity to enhance effective energy efficiency, considering that approximately 60 % of the total energy input is lost through this component. Addressing this substantial energy loss becomes essential for achieving a more energetically sustainable industrial application of the FSW/P process.