A solar thermal power system includes a solar receiver for heating thermal energy storage fluid to be stored and utilized from a thermal energy storage arrangement having hot and cold storage tanks. The system includes a steam generator arrangement, which utilizes the heat of the thermal energy storage fluid to produce steam to run a turbine. The arrangement includes a bypass line configured to bypass the hot storage tank from the steam generator arrangement, and to supply the hot thermal energy storage fluid from the solar receiver directly to the steam generator arrangement, during day times, when the solar receiver the steam generator arrangement are both in operating mode, thereby recovering stored potential energy available in the down corner hot thermal energy storage fluid from the solar receiver.