Apparatus and methods for controlling an ultraviolet (UV) sterilization system that has one or more UV sources to achieve proper sterilization with minimal time and usage of power for the UV sterilization system. The UV sources are operated according to a set of control parameters including intensity of the UV light energy and an exposure time. The device may include: one or more sensors that are configured to measure UV light energy emitted by the UV sources and develop one or more signals; and a microcontroller that has an access to information of UV energy doses for various types of microorganisms. The microcontroller is configured to receive the signals from the sensors, determine a set of optimum values corresponding to the set of control parameters using the signals and the information, and send the set of optimum values to the UV sources to control the UV sources.