Efficiency of HVAC power transmission from offshore-windmills to the grid

For large offshore windparks far away from the coast, not only the investment costs of the transmission system but, moreover, the costs of the transmission losses play a decisive role for the economy of the total power system. In this paper some basic problems in determining the losses of HVAC transmission systems are discussed, taking into account the longitudinal distributions of current and temperature as well as the time-dependence of the power flow.