It is a system for supplying power to at least one load. The system comprises at least one power source, load bank and control device coupled to the at least one load. The load bank is coupled to at least one power source and at least one load. The load bank comprises a controllable voltage source, at least three resistors coupled between an output side of the controllable voltage source and the at least one power source, and at least one storage element. The controllable voltage source comprises more than one switches. And the at least one storage element comprises one or more capacitors, batteries, or combinations thereof. The control device is configured for controlling the switches during a first condition such that, to the extent that an output power of the at least one power source exceeds a requisite power of the at least one load, any excess output power is either supplied to the at least one storage element or consumed by the at least three resistors. This invention also provides a method for supplying power to at least one load.