The increasing amount of decentralized and fluctuating power generation and an increasing number of electric vehicles, heat pumps and other new consumption appliances pose major challenges to distribution system operators. However, this also offers new opportunities for improved usage of distribution grid assets. Instead of extending grid assets in the conventional way (e.g. with additional and/or higher capacity of cables and transformers), the supply to consumers may be better achieved by exploiting the flexibility of appropriate devices using ICT. This approach is the objective of a "Smart Operator", which is conceptually presented in this paper.

The massive integration of dispersed generation of combined heat and power units (CHP units) brings up challenges for today's distribution networks that they not have been planned for. However, it is not yet fully understood in which areas and under which precondition, CHP units shall be installed and could be efficiently operated with minimum environmental impacts. In this paper an analysis of different energy supply scenarios for different distribution networks in Germany in 2030 evaluating the environmental impacts and the effects on grid planning is presented. Based on a comparison of these scenarios recommendations are given in which areas and under which preconditions a local heat and power supply with CHP units is more environmental friendly compared to centralized power generation in large power plants combined with conventional heating systems.

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Thanks to the fast expansion of Dispersed Generation (DG), Germany's rural electric distribution grids are undergoing a process of rapid transformation to multidirectional energy networks. Latest analysis shows that new Voltage Controlled Distribution Transformers (VCDT) using an integrated on-load tap changer can not only be used for highly efficient LV grids, but might possibly be applied area-wide to avoid rural MV network expansion. VCDT technology opens up the static connection of conventional local transformers between MV and LV grids. It allows for the use of the entire voltage bandwidth of EN 50160 in each voltage level in an efficient way.In this paper, the idea of using VCDT-technology for an area-wide dispersed voltage control is at first explained, then shown in its effects on rural MV grids and finally discussed in its advantages and disadvantages.

Curtailment of distributed generation and demand side management may be a feasible alternative to network expansions in future medium voltage networks. Hence both must be considered in network planning today to develop cost efficient networks. Different control strategies are possible and each will result in a distinct optimal network structure. Network and energy costs will also differ. So far network operators and regulators do not know what control strategy should be striven for. Furthermore no planning algorithm exists that allows considering different control strategies. In this paper, a new algorithm is presented in this paper to solve the planning and control problem in an integrated manner. The distribution system operator of the city of Aachen (STAWAG) has decided to use this algorithm to evaluate different control strategies and derive an optimal long term network structure. The results of this study are also elaborated in the following.