## 1 Introduction  
The conflict between fast-rising global energy demand and climate change is a major challenge that requires significant science and technology innovations. Advanced manufacturing has the potential to reduce greenhouse gas emissions and pollution significantly and shorten the time-to-market [1]. Additive manufacturing (AM) is defined by the ASTM society as the \"process of joining materials to make parts from 3D model data, usually layer upon layer, as opposed to subtractive manufacturing and formative manufacturing methodologies\" [2]. In general, AM eliminates the design and fabrication restrictions of conventional manufacturing (CM) methods to a large extent. As an emerging and transformative technology, AM and 3D printing offer great potential for the energy sector by decreasing the lead time, improving energy efficiency, eliminating the cost of molds and special tools, and allowing for increased customization of parts [3]. According to estimations, the global power system of 2050 will require four times today's generation capacity and will need to transfer three times as much electrical energy [4]. Therefore, more sustainable manufacturing technologies (such as additive manufacturing) and advanced design concepts will play an important role in the minimization of material usage and reduction in waste material generated. Despite the positive aspects, several challenges eliminate the adaption of this technology to the industry application. Production volume,standards compliance, product quality and properties, post-processing, size limitations, and metal AM cost are some of the most important drawbacks in the path of using AM [5]. In the energy sector, AM has already demonstrated its potential in producing customized parts for wind turbines, gas turbines, solar energy production equipment, fuel cells, and batteries [6; 7; 8; 9]. In addition, the possibility of employing AM technologies on-site to produce spare parts for the replacement of damaged components in oil and gas equipment and facilities has been considered. Although the reduction in production downtime and replacement costs are considered benefits, the future of AM in the oil and gas industry needs further research in the area of new materials development processing, the improved surface finish of AM fabricated parts, enhanced fabrication speed, and parametric optimization to improve the mechanical properties of the fabricated components [9]. AM in energy will undoubtedly bring the expanded application to nuclear energy. Numerous investigators will join early adopters in applying existing commercial AM methods and developing new approaches to nuclear fuel fabrication [10]. Moreover, AM and 3D printing in power electronics and converter applications have been explored, focusing mostly on inductors and copper-printed windings [11]. Printing of magnetic materials with respect to the topology optimization for electrical machines has been discussed [12]. The application of 3D printing for the manufacturing of high-voltage transformer insulation has been investigated, and several challenges have been identified when considering 3D printing. The presence of internal voids in the printed insulation is one of the main issues for high-voltage transformer insulation [13]. In another study related to AM for HV application, additive manufacturing of polymeric components used in an HV apparatus was discussed, indicating that because of printing limitations, such technology can be used only for non-critical parts [14]. Considering the previous publications, it is clear that AM for high-voltage applications has not been investigated deeply, especially for metallic alloy parts. This could be related to specific requirements in such applications, as well as the large sizes of the products. Therefore, this study focused on the feasibility of AM in high-voltage products and considered a gas-insulated high-voltage switchgear as a case study.