-Deregulation and an increasing competition in electricity markets urge energy suppliers to optimize the utilization of their equipment, focusing on technical and cost-effective aspects.As a respond to these requirements utilities introduce methods formerly used by investment managers or insurance companies. The article describes the usage of these methods, particularly with regard to asset management and risk management within electrical grids. The essential information needed to set up an appropriate asset management system and differences between asset management systems in transmission and distribution systems are discussed.The bulk of costs in electrical grids can be found in costs for maintenance and capital depreciation. A comprehensive approach for an asset management in transmission systems thus focuses on the "life-cycle costs" of the individual equipment. The objective of the life management process is the optimal utilisation of the remaining life time regarding a given reliability of service and a constant distribution of costs for reinvestment and maintenance ensuring a suitable return.In distribution systems the high number of components would require an enormous effort for the consideration of single individuals. Therefore statistical approaches have been used successfully in practical applications. Newest insights gained by a German research project on asset management systems in distribution grids give an outlook to future developments.

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The area-wide installation of smart meters in low voltage (LV) grids prospectively provides information about the relevant operational system parameters, e.g. complex node voltages and line loads. Under the condition of neglected house to grid connection lines, a positive local measurement redundancy at every network node is obtainable. In general, this enables the implementation of special three-phase LV state estimation (SE) systems with the ability of bad data detection. In the future, such SE systems might be the basis for closed-loop network control systems without any operator interventions. This paper proposes a concept for a LV state estimation system based on smart meter data. In contrast to other approaches, a linear SE algorithm is used, so that the SE system is not prone to convergence issues. Input variables are voltage and current magnitudes as well as active and reactive currents. The bad data detection process is generally based on the well-known method of normalized residuals. To ensure correctly applied network topologies also in meshed networks, a novel algorithm for detecting topology faults is used. The presented results gathered from simulations and a field test are promising, showing appropriate accuracies and bad data detection probabilities especially for voltage magnitude and active current bad data.