The present invention relates to a method for controlling operation of an electric motor in a height-adjustable furniture arrangement, wherein operation of the electric motor provides a height-adjusting function in the height-adjustable furniture arrangement. The method comprises the steps of providing, by a power supply unit connected to the electric motor, an incoming power comprising an incoming current and an incoming voltage, transforming the incoming current and the incoming voltage to a motor supply current and a motor supply voltage supplied to the electric motor, measuring load on the electric motor, and when the measured load requires a current higher than the incoming current for providing the height-adjusting function, setting the levels of the motor supply current and/or the motor supply voltage such that the motor supply current is higher than the incoming current and the motor supply voltage is lower than the incoming voltage.