A method to adaptively and dynamically set a bias scheme of a crossbar array for a write operation includes: performing a read-before-write operation to determine a number of cells n to be written during a write operation; comparing n to a predetermined threshold value to determine an efficient bias scheme; setting at least one voltage regulator to provide a bias voltage according to the efficient bias scheme; and performing the write operation. A method to determine threshold value to determine an efficient bias scheme of a crossbar array and an energy efficient crossbar array device are also described.