A method of operating a Heating, Ventilating, and Air Conditioning (HVAC) arrangement for a building, the HVAC arrangement comprising an Air Handling Unit loop with at least one AHU, with at least one electric chilled water pump, and with at least one electric AHU fan for supplying air to the building from the AHU, wherein cooling water is circulating in the AHU loop, a cooling tower loop with at least two cooling towers, each cooling tower comprising at least one electric cooling tower fan, and with at least one electric condenser water pump, wherein condenser water is circulating in the cooling tower loop, at least one chiller, the chiller comprising an evaporator, an electric compressor, a condenser, an expansion valve, and a refrigerant, which form a thermodynamic refrigeration cycle which interconnects with the AHU loop and with the cooling tower loop such that heat is transferred from the cooling water to the condenser water, and a Master Controller for controlling the at least one electric chilled water pump, the least one electric AHU fan, the at least one electric cooling tower fan, and the at least one electric condenser water pump, the method comprising the MC changing speed of the at least one electric chilled water pump such that a return chilled water temperature does not exceed a predetermined upper limit of return chilled water temperature and such that a delta T value of the chilled water does not exceed a predetermined thermal comfort delta T limit, the MC changing speed of the at least one electric condenser water pump such that a return condenser water temperature does not exceed a predetermined upper limit of return condenser water temperature and such that a delta T value of the condenser water does not exceed a predetermined delta T limit, and the MC selecting a number of active cooling towers with adjusting speed of their respective cooling tower fan, wherein the aforementioned steps are provided in a balanced state of heat transport rate from the AHU to the cooling tower, and such that the same heat transport rate between the AHU and the chiller is maintained, while overall energy consumption is reduced. an Air Handling Unit loop with at least one AHU, with at least one electric chilled water pump, and with at least one electric AHU fan for supplying air to the building from the AHU, wherein cooling water is circulating in the AHU loop, a cooling tower loop with at least two cooling towers, each cooling tower comprising at least one electric cooling tower fan, and with at least one electric condenser water pump, wherein condenser water is circulating in the cooling tower loop, at least one chiller, the chiller comprising an evaporator, an electric compressor, a condenser, an expansion valve, and a refrigerant, which form a thermodynamic refrigeration cycle which interconnects with the AHU loop and with the cooling tower loop such that heat is transferred from the cooling water to the condenser water, and a Master Controller for controlling the at least one electric chilled water pump, the least one electric AHU fan, the at least one electric cooling tower fan, and the at least one electric condenser water pump, the method comprising the MC changing speed of the at least one electric chilled water pump such that a return chilled water temperature does not exceed a predetermined upper limit of return chilled water temperature and such that a delta T value of the chilled water does not exceed a predetermined thermal comfort delta T limit, the MC changing speed of the at least one electric condenser water pump such that a return condenser water temperature does not exceed a predetermined upper limit of return condenser water temperature and such that a delta T value of the condenser water does not exceed a predetermined delta T limit, and the MC selecting a number of active cooling towers with adjusting speed of their respective cooling tower fan, the MC changing speed of the at least one electric chilled water pump such that a return chilled water temperature does not exceed a predetermined upper limit of return chilled water temperature and such that a delta T value of the chilled water does not exceed a predetermined thermal comfort delta T limit, the MC changing speed of the at least one electric condenser water pump such that a return condenser water temperature does not exceed a predetermined upper limit of return condenser water temperature and such that a delta T value of the condenser water does not exceed a predetermined delta T limit, and the MC selecting a number of active cooling towers with adjusting speed of their respective cooling tower fan, wherein the aforementioned steps are provided in a balanced state of heat transport rate from the AHU to the cooling tower, and such that the same heat transport rate between the AHU and the chiller is maintained, while overall energy consumption is reduced.