Reviewing High Voltage Transmission Technologies for Future Transmission Grids

The European Union's ambitious decarbonization goals by 2050 foresee a considerable amount of renewable energy sources capacity installed in its territory. This goal calls for a fundamental upgrade of the transmission grid to deliver the generated renewable power to the load centers distributed in the different countries. This paper presents a comprehensive review of different multi-GW high voltage transmission technologies, including high voltage AC and DC (for both overhead lines and cable Systems), superconducting cables, gas-insulated lines, and hydrogen technologies. The review evaluates each transmission technology based on key parameters such as capacity, use of materials, spatial requirements, reliability, and the need for auxiliary equipment. The results provide a comparative analysis, with a highlight of the potential and challenges of each technology. These findings focus on the critical role of high voltage transmission systems in enabling large-scale renewable energy integration and achieving a net-zero emission future grid by 2050.