Additive manufacturing (AM) is used in metal part forming for its innovative character but its potential for sustainability is uncertain. The energy and material consumption required for manufacturing are significant. Thus, the research question of this article is: "What are the current uses of AM that present a real potential for reducing environmental impact?". The WAAM (Wire Arc Additive Manufacturing) process appears to be the most energy-efficient in comparison to other AM processes. A process parameters study shows that deposition rate has a substantial impact on energy consumption. This parameter represents the amount of material deposited in a unit of time and is directly linked to productivity. It appears that an increase of the deposition rate leads to a reduction in energy consumption. Experiments on WAAM with a high deposition rate permits to create a database of energy and material consumption. This database is then used to identify cases of parts made with WAAM that offer a significant impact reduction compared with conventional manufacturing processes.