WIND TURBINE BLADE HAVING AN ELECTRO-THERMAL SYSTEM

A wind turbine blade comprising suction and pressure side shell parts of an aerodynamic shell body extending in a longitudinal direction between a root end and a tip end and in a transverse direction between a leading edge and a trailing edge, and an electro-thermal system comprising suction and pressure side heating layers comprising electrically conductive fibres to mitigate ice formation on the wind turbine blade; suction and pressure side metallic lightning protection layers for receiving a lightning strike and arranged exteriorly to and overlapping the heating layers; and a down conductor being electrically connected to the metallic lightning protection layers so as to be able to conduct a lightning strike current from the metallic lightning protection layers to a root of the wind turbine blade, wherein the electro-thermal system comprises at least one equipotential bonding conductor electrically connecting the electrically conductive fibres of the suction side heating layer and the electrically conductive fibres of the pressure side heating layer to form an equipotential bonding;