Gas-insulated lines

Gas-insulated lines (GIL) consist of two concentric aluminum pipes: a guide pipe and an encapsulated pipe. The space between the two pipes is filled with an insulating mixture of nitrogen and sulfur hexafluoride. In transmitting energy in high-voltage power grids, GILs are suitable for direct and alternating current and can be laid both above and below ground. They feature high transmission capacities, very weak electromagnetic fields and a high degree of reliability. Their transmission losses are up to 70% lower than those of overhead lines.