Within this paper the gate-level power-simulation tool GliPS (Glitch Power Simulator) is presented, which gives excellent accuracy (in the range of transistor-level simulators) at high performance. The high accuracy is achieved by putting emphasis on delay- and power-modelling. The impact of these modelling factors on accuracy and performance is demonstrated by comparing GliPS to other tools on circuit-level and a simple toggle count based power simulator TPS on gate level.