"Diverse geopolitical, market integration and techno-economic dynamics push for further interconnecting the higher voltage systems across countries and continents. The best locations for the generation of renewable electricity are not uniformly distributed across the European continent and worldwide. Sizable renewable energy potential is concentrated in sites far from the power grid (e.g. offshore sea) or where grid transfer capacity is low. The energy production from renewable sources also greatly depends on local weather conditions. To fully utilise these resources, the power grid must be enhanced to allow electricity to be transported to the main demand and storage centres. A more flexible, yet robust, transmission grid may be instrumental to interlink distant electricity markets and take advantage of the low-carbon resources temporal and spatial complementarity. All the above may drive the realisation of a transcontinental higher transfer capacity system to transport large amounts of electricity over long distances. High Voltage Direct Current (HVDC) technologies, due to their lower losses and smaller environmental impact, promise to be the cornerstones of such global power grid..."