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Although a recent report by the U.S. Energy Information Administration indicates that CO 2 emissions from power generation have now fallen below emissions from the transportation sector, electricity use remains a significant part of human's environmental footprint since fossil fuels are the major energy resource for electricity generation worldwide. This explains the continual effort by policy makers to develop a remedy to mitigate carbon emissions. It is then critically important to properly account for the emissions associated with electricity generation, delivery, and consumption. In particular, it is critical to be able to allocate emissions to the relevant electricity consumers creating the demand that results in a polluting emission. Therefore, in this paper a virtual carbon emission tracing method in power systems is thoroughly presented to facilitate allotting carbon obligation. The method is developed based on the proportional sharing principle that has been used in power system operation. The proposed methodology is implemented on the IEEE 5-bus and 9-bus systems, two widely used and recognized power grid benchmarks.

Various technical limitations of generating units and ancillary services requirements have more complicated the power generation control and operation. This paper introduces a novel methodology for day-ahead unit commitment, which is a crucial challenge in restructured power systems, considering primary frequency control reserve. In addition, also spinning reserve uncertainty as a practical constraint has been taken into account. In this paper, we formulate and solve simultaneous scheduling of energy and primary reserve as a mixed integer non linear programming problem that simultaneously accounts aforementioned constraints. In proposed formulation, system frequency is allowed to fall from nominal value to a critical specified limit. Finally, the proposed approach is implemented to the scheduling of a 17-unit isolated power system over 24-hours. Case studies and numerical results present significant outcomes and verify the robustness of the proposed method, while it creates a schedule consistent with the primary frequency control and spinning reserve uncertainty.

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Summary Electricity consumption has been increasing worldwide, and the growth is still significant, particularly in developing countries. When power consumption increases, the entire system is at a risk of voltage collapse. Power distribution companies have been using step‐up transformers or on‐load tap changing systems to overcome this crucial challenge. These devices are capable of increasing voltage and consequently promoting static voltage stability margin of the network. To use such equipment, it is essential to determine the optimal location and voltage ratio. This paper analytically investigates the presence of a step‐up transformer in a medium‐voltage radial feeder for improving voltage stability. The paper also introduces an easy‐to‐use coordinate rotation that provides a more tangible graphical representation of static stability of power systems. Furthermore, an open‐source software application, developed by the authors, to calculate voltage stability limit of power systems is introduced in this paper that is publicly available.