The hosting capacity for distributed energy resources (DER) identifies the acceptable degree of DER penetration under given circumstances. It depends on various parameters such as the characteristics of the generation units, the configuration and operation of the network, the requirements of the loads as well as national and regional requirements. To determine the hosting capacity and to find ways to expand it by overcoming existing barriers is one subject of the ongoing European research project EU-DEEP. This paper describes the impacts of non-controlled DER units on the resulting voltage profiles as these impacts showed to be a main limitation for the hosting capacity for DER in existing distribution networks. The methodology for the analysis is introduced and basic results of the case studies performed are demonstrated. Generally the hosting capacity for DER can be extended applying different technical measures all leading to additional investments into the network. In future active distributions networks will provide a cost-effective solution to increase DER penetration. IMPACT OF DER ON VOLTAGE PROFILE Voltage control in existing distribution systems is based on radial power flows from the substation to the loads and on the fact that real power magnitude decreases with increasing distance from the substation. But, the introduction of DER in distribution systems impacts the methods of voltage control. DER may change the direction of power flows. This may lead to a reduced performance of the voltage control. It remains required that the system operates with adequate security and within statutory limits,. despite the fact that the Distribution System Operator (DSO) does not exert control over the generation..

This paper presents the main features and the use of the security constrained optimal power flow program, called IPSO (Integrated Power System Optimizer), in the electricity market environment. The finding of the optimal power flow solution is realized with the KNITRO solver developed at Ziena Optimization, Inc. The paper emphasizes the original features of IPSO software such as security constrained modeling in both preventive and corrective strategy, the discrete variables modeling, the modeling of units' capability curves, the modeling of the primary active power-frequency control as well as the modeling of the primary active power-frequency control. Finally, is presented the utilization of the SCOPF program to evaluate the steady state TTC (Total Transfer Capability).

An organic–inorganic hybrid compound [(CH3)2NH2]2ZnBr4 has been prepared at room temperature under the slow evaporation method. Its structure was solved at 150 K using the single‐crystal X‐ray diffraction method. [(CH3)2NH2]2ZnBr4 crystallizes in the monoclinic system – a = 8.5512 (12) Å, b = 11.825 (2) Å, c = 13.499 (2) Å, β = 90.358 (6)°, V = 1365 (4) Å3, and Z = 4, space group P21/n. In the structure of [(CH3)2NH2]2ZnBr4, tetrabromozincate anions are connected to organic cations through N–H⋯Br hydrogen bonds. Differential scanning calorimetry (DSC) measurements indicate that [(CH3)2NH2]2ZnBr4 undergoes four phase transitions at T1 = 281 K, T2 = 340 K, T3 = 377 K, and T4 = 408 K. Meanwhile, several studies including DSC measurements and variable‐temperature structural analyses were performed to reveal the structural phase transition at T = 281 K in [(CH3)2NH2]2ZnBr4. Conductivity and dielectric study as a function of temperature (378 < T [K] < 423) and frequency (10−1 < f [Hz] < 106) were investigated. Analysis of equivalent circuit, alternating current conductivity, and dielectric studies confirmed the phase transition at T4. Conduction takes place by correlated barrier hopping in each phase.

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A disodium cobalt(ii) orthosilicate material has been synthesized using improved solid-state and co-precipitation methods of synthesis. The Rietveld refinement of the XRD pattern of Na2CoSiO4 demonstrated an orthorhombic crystal system.

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