It is common knowledge that transmission systems are being pushed ever closer to their stability and thermal limits. Traditional solutions for upgrading electrical transmission system infrastructure have been primarily in the form of new power plants, new transmission lines, substations, and associated equipment. However, as experience has proven, the process of authorizing, locating, and constructing new transmission lines has become extremely difficult, expensive and time-consuming. This is the reason why during the last few years interest in dispersed generation, power flow controlling or/and energy storage has increased significantly – interest in solutions which can improve the efficiency of the distributed power system. With respect to the above the major aim of this paper is to present the fundamental problems of the Power Systems and the improvement methods which arise using Distributed Generation. The paper introduces also a system for the utilization of energy generated on the customerside – this arrangement is realised using a Voltage Active Power Filter. The experimental results presented in the paper confirm the flexibility of this arrangement in efficiency improvement processes.