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As businesses grow, trust among participating stakeholders assumes prime importance. The transparency and efficiency in the transactions that occur in these businesses are equally valuable as the profits. Digitization of the economy helps ease-out the conduct of business; however, the increase in vulnerability to cyber-attacks is also on the rise. Blockchain technology revolutionizes the way digital transactions can occur and holds much promise in securing the flow of information that primarily drives them. Such a distributed ledger framework allows the traceability of a transaction through its immutable chain of blocks. Each block registers a time-stamped information set, verified by all the stakeholders involved in the business. These sets of features and much more make the blockchain technology an immensely powerful force to bring in transparency, efficiency, and trust in various industries. The paper’s primary focus is given the features that empower a blockchain to facilitate various tasks securely, efficiently, and smoothly in a power sector. It also gives impressions of pilot projects in India with blockchain applications in different sectors. Glimpses of a prototype developed by the authors for managing the trading of rooftop solar energy among a set of consumers have been provided as one of the applications in power distribution.

In this paper, a Battery Energy Storage System (BESS) based solution has been proposed to reduce the fluctuations in the output power of large solar Photovoltaic (PV) parks. This will contribute to reduction in the frequency deviations of large power systems and moderating pressure on conventional power plants with the increasing penetration of solar power. Solar PV smoothening is one such application of BESS to moderate inherent intermittencies of solar PV power plants. Different methods adopted for smoothening of solar PV output could lead to arrival of different sizes of the batteries. Thus, assessment of various methods to smoothen PV output power and scope of smoothening becomes significant. A technique has been proposed and has been evaluated against different existing methods for comparing the performance. The results from the proposed technique have been found to be encouraging in terms of determining the battery life and size.

Electric Vehicles (EVs) are becoming an integral part of the transportation fleet in many countries. They have substantially progressed to become a mainstream component of the smart electricity grid and are catalyzing changes in policies and regulations relating to power distribution systems. EVs represent distributed storage units whose load depends on the driving patterns and the battery charging characteristics. Random and uncontrolled EV charging has implications on both the network loading and the charging cost since time-based pricing is in effect for many utility companies. A well-managed charging system is thus important and must consider asset loading as well as time-varying tariff. This paper presents a regulated charging scheme that takes into account the charging cost which is reflective of both the transformer loading and the utility-level Time of Day (ToD) tariff. The task of finding a charging schedule that gives the least overall charging cost for the day has been formulated as an optimization problem for an actual distribution utility in India. The driving pattern was estimated based on a survey of EV owners plying in the utility license area. The results demonstrate how such a controlled charging scheme can save on the customers’ money and help the utility manage its load curve by ensuring that the distribution transformers serving the EVs are not overloaded.

Widespread adoption of Electric Vehicles (EVs) for light, medium, and heavy-duty applications has gained significant interest. Based on ownership and user preferences, light duty and local delivery medium-duty EVs are typically connected to grid distribution networks whereas larger medium duty and heavy-duty EVs are typically connected to distribution or even sub-transmission networks. Challenges with at-scale EVs and charging infrastructure supporting them include interoperability, distribution network upgrades, surge in demand charges, power quality issues, voltage stability, etc. Based on real-world data, steady-state and dynamic assessments of light-duty EV charging with a focus on DC Fast Charging (DCFC) for weak distribution grids is presented. Three main areas of contributions in this paper include - steady state and dynamic power quality measurements and assessments using real world data, transient assessments of light duty EV integration with weak distribution networks (IEEE 13 node feeder system) under grid-connected and microgrid modes, and formulation of an intelligent charging decision algorithm to enable an impact-minimal charging.

The number of Electric vehicles (EVs) in the transportation fleet of many countries is increasing rapidly to tackle rising air pollution levels. In terms of running costs and ability to support the utility power grid, electric mobility clearly standsout amongst the non-fossil fuel based transportation alternatives. Electric vehicles are distributed energy storage units that can act as energy sources to the local distribution network. Therefore, EVs can work in two modes that support bidirectional power flow: charging or discharging known as Grid to Vehicle (G2V) and Vehicle to Grid (V2G) modes respectively. In the V2G mode, EVs can help the grid by providing reactive power support and also mainly by discharging during peak load times to improve efficiency & reliability, provide V/f regulation, manage renewable energy intermittency and provide load balancing with Demand Side Management (DSM) as a set of possible ancillary services. The challenges associated with V2G system include life cycles lost and battery degradation, changes required in the grid infrastructure/equipment, energy losses and the huge investment cost involved. This paper gives an account of the advantages and disadvantages of V2G system for EV owners and grid operators.

Distribution transformers are one of the critical components of a distribution network involving huge capital investments and requiring special care to be ensured during their operation. Overloading of distribution transformers must be avoided beyond a certain threshold after which the capital-intensive process of their augmentation or replacement becomes inevitable. The cumulative peak demands of many distribution transformers contribute to the feeder peak and conditions of overloading lead to costly peak power purchases. Increasing penetration levels of distributed solar photovoltaic power on distribution transformers is also adding to the stress in the form of sudden variations in the net-load. Installation of battery energy storage systems at the secondary side of distribution transformers can provide a lot of techno-economic benefits in mitigating these conditions. This paper presents a two-stage approach for sizing such a system for one of the selected distribution transformers on an actual distribution feeder operational in Delhi, India. The intended application is overload management and peak shaving. The results of the preliminary sizing stage are rigorously tested against different sensitivity scenarios in terms of the number of continuous overloading instances in a year. In the advanced stage, the charge rate and the total amount of unmet energy are used as a feedback to fine tune the size so as to optimally meet the application.

Rooftop solar photovoltaic installations have grown rapidly across India. Their integration with the local distribution networks may throw some operational challenges with increasing penetration levels. Voltage rise or unbalance and reverse power flows are some of the anticipated concerns. The current grid-connectivity regulations in India only encourage unity power factor operation of solar photovoltaic inverters although reactive power support features are available in commercial models. However, with increasing solar power into the distribution network, smart inverter functionality will assume importance. This paper analyzes the effect of Volt-VAr control mode of solar photovoltaic inverters in providing localized voltage control and reducing reverse power flow. An actual feeder of a distribution utility in Kolkata, West Bengal, India has been extensively modeled and distribution load flow studies have been performed. The preliminary results of this modeling exercise have shown encouraging results in simulation, in support of smart inverter functionality. The need for modeling distribution networks in greater detail beyond the distribution transformer secondary has also been established in order to have a realistic assessment of the impacts of integration of rooftop solar systems.