A lightning protection or internal surge device designed to suppress surges on electrical transmission or distribution lines by expending some of the excess energy in the form of corona discharge in both wet and dry conditions. The device is a very thin (of diameter not exceeding 0.1 mm) conducting wire, fiber, filament, or a bundle of such filaments, or a yarn or woven or knitted fabric made of such fibers or wires which is wound around a live conductor or ground wire forming a coil. When the coil is exposed to the fields created by the voltage surges on the line or ground wire it enhances corona losses on the line thereby damping/suppressing the surges as well as prolonging the front time of the surge to reduce its steepness.