N.P. Padhy’s research while affiliated with Indian Institute of Technology Roorkee and other places

India has gargantuan renewable energy sources. The ministry of new and renewable energy, Government of India has adopted rigorous process of implementation of number of encouraging renewable energy programs. A road map has been provided in various policies to shore up the deployment of renewable energy across the country. The distributed solar photovoltaic (SPV) power plants are envisaged to have record growth in India owing to due technology diligence, reducing costs and supportive government policies in renewable rich states. Distributed SPV will gradually become a vital component of energy mix of country. The small gestation period of these plants would help to meet power shortages and improve the grid situation. The issues and challenges of connectivity of distributed energy sources into grid are being addressed by adopting suitable technologies and policies framework. The paper provides the comprehensive study of development of SPV power plants in India.

Pumped-hydro energy storage schemes (PHES) are developed for improving the net efficiency of the base load thermal power plants. These schemes are operated only at times of peak demand and during major power plant outages. In India, the first pumped storage plant was commissioned during 1985 and till today eleven plants with on aggregate installed capacity of 4804 MW have been in operation. However all these plants up to the year 2003 have generated energy less than the projected figures. The major reason for less output from the PHES in India, than that envisaged in the planning stage is deficit of off-peak power availability for pumping operation in almost all the regional power grids except north-eastern grid. But gradual increase in efficiency has been realized from PHES operation after introduction of the availability based tariff (ABT) in 2003. Further, the increase in peak power demand, requirement of spinning reserve, increased generation from renewable energy sources have singly and combinedly triggered the necessity for installation of more pumped storage schemes in the country. Under these circumstances, this analysis addresses the economics of pumped storage schemes in India with special reference to Kadamparai PHES. Various costs involved in pumped storage operation are analyzed in the Indian context. The case study reveals considerable techno-economic benefits obtained by more operational hours of the PHES in the state grid after 2003. The analysis and results would be useful for investors and researchers to understand the economics of Indian pumped storage schemes.

This article evaluates the performance of electricity distribution divisions (EDDs) of an Indian state utility namely, Uttarakhand Power Corporation Limited (UPCL) in terms of overall efficiency through data envelopment analysis with an objective to trace the effectiveness of an ongoing restructuring process. Relative efficiencies of the divisions are compared for the period 2005 to 2008. Further using the Malmquist productivity index and its decompositions, productivity change is investigated for EDDs during the same period. This study gives an assessment of UPCL to monitor and diagnose the changes in the productivity of EDDs, so it will help regulators to formulate more effective policies on deregulation and disintegration and to determine the appropriate productivity factor when imposing yardstick competition on electric utilities.

v>This paper presents a minimum deviation index based multi objective methodology for solving reliable/emission/economic dispatch (REED) problem. The REED problem is formulated as a non linear and constrained optimization problem with competing and non commensurable objectives. The three competing objectives such as fuel cost, emission and reliability function are optimized simultaneously using the proposed cuckoo search algorithm (CSA). Here the conflicting functions are formulated as a single objective function using tuned fuzzy weighted minimum deviation index. The proposed algorithm is tested on the standard 6, 10 and 26 unit systems. Simulation results are compared with the solutions available in the literature.

While carrying out renovation and modernization, introducing new technologies for improving the power station performance is a universal practice. In this context a study has been conducted for the 26 year-old Kadamparai pumped storage plant (4 × 100 MW) located in the state of Tamil Nadu, India, with the objective of adopting variable speed technology while undertaking renovation & modernization in not-so distant future. Present peak power demand and the expected capacity addition through thermal, nuclear, solar, wind energy power plants to the state grid needs a review on the existing operation of Kadamparai pumped storage plant to meet out the peak and energy shortage of the state. The existing conventional synchronous machines of this plant can be operated as variable speed machines by adopting static frequency converters (SFC) between stator and grid supply or replacement of existing synchronous machines with variable speed induction generators to utilize the grid load variation effectively. Annual operation of Kadamparai pumped storage scheme with variable speed machines has been analyzed in the existing hydraulic conditions. Additional benefits that is likely to accrue as compared to conventional synchronous speed operation has been calculated. Results show that the variable speed technology has considerably increased the plant performance.

This article describes the growth of transmission sector and basic concept for the allocation of tariffs in the Indian scenario. Different phases of transmission pricing reform have been discussed. The article focuses on the existing transmission pricing mechanism with its limitations and the different initiatives taken by the Central Electricity Regulatory Commission for reforming the pricing mechanism as mandated by the Electricity Act 2003. Finally, some challenges for reforming transmission pricing have been discussed.

The growing economy with corresponding increase in power demand causes more challenges in power sector of developing countries. In India, the increase in peak power demand necessitates energy storage schemes over and above the storage-hydro-, oil- and gas-based peak power plants to ensure power system stability. In utility energy storage schemes, the Pumped storage schemes attract more attention even in the developed countries due to its unique operational flexibility over other energy storage systems. In India, the availability of suitable topographies, hydro-thermal ratio imbalance in various regions, and optimal storage capacity for flexible power system operation gives a thought for the planers and executors to implement these schemes to meet peak demands. This paper presents a critical review of the necessity of pumped storage schemes in India. This review reveals that the major constraint for pumped storage operation in India is the deficit of off-peak power available in all the regional grids except north-east region for pumping at present. But the current adversity is likely to be gradually solved by the commissioning of newly proposed power projects. Fixing of a separate operational tariff for pumped storage schemes throughout the country is another requirement for which the government has set up a one man committee to analyze the feasibility for this peak tariff. Non-availability of lower tail pools and irrigation needs also causes poor pumping operations in some cases. However, most of the states in India are evincing interest in pumped storage schemes and proposals are being submitted to central government for securing stations clearance.

This paper evaluates relative performance of the Electric Distribution Divisions (EDDs) of an Indian State, Uttarakhand for the period 2005–2008, through application of Data Envelopment Analysis (DEA). To improve the operational efficiency of EDDs, Uttarakhand Power Corporation Limited (UPCL) disintegrated several divisions into smaller ones over this period. However, microlevel examination revealed the ineffectiveness of this process during the period of analysis. Therefore, in the present work an alternative reorganization model for selecting the EDDs for disintegration and for selecting the optimum scale for disintegration is proposed based on the efficiency analysis of 2007. The model is verified by comparing the mean efficiency score of the EDDs derived using proposed model with that of existing ones. It is found that overall efficiency of proposed model is higher than the existing system. Reliability of the overall efficient EDDs is also examined to check the robustness of the CCR result for the same year. This study gives an assessment of UPCL to monitor and diagnose the changes in the efficiency of EDDs, so it will help regulators to formulate more effective policies on deregulation and disintegration and to determine the appropriate efficiency improvement measures when imposing yardstick competition on electric utilities.

Security-constrained unit commitment (SCUC) problem is solved using ABC algorithm incorporating Interline Power Flow Controller (IPFC). The percentage of cost recovered with the installation of IPFC is also analyzed. The objective of the SCUC problem is to obtain the minimum operating cost simultaneously maintaining the system security. The SCUC problem involves unit commitment problem as the main problem and security-constrained Economic Dispatch (SCED) as the sub problem. The prevailing generation constraints, such as hourly power demand, fuel and emission limits, system reserves, and minimum up/down time limits, ramp up/down limits, are included in the SCUC problem formulation. The capability of IPFC to control the power flow through transmission lines is discussed. The gain obtained with the installation of IPFC is demonstrated with respect to the Equated Monthly Installment (EMI) paid and the installation cost. Binary coded artificial bee colony (BABC) is used for solving the UC problem (master problem) and real coded artificial bee colony algorithm (RABC) is used for solving the SCED sub problem. The effectiveness of the proposed methodology is tested and validated on an IEEE 118 bus test system and a practical South Indian 86 bus utility.

Network pricing is a complex issue, considering the network size and other facets. For distribution networks, reference network aids in quick decision making, for network operation and pricing. There is a sustained interest for development of dynamic network pricing mechanisms to reflect network cost on a real time basis. Recent developments in smart grid technologies have offered opportunities to utilise these innovative technologies for real time network pricing. The paper proposes an integrated framework for providing dynamic network pricing for practical distribution networks. This framework introduces an integration of network reconfiguration algorithm in association with reference network formation algorithm. Considering the dynamic nature of networks, their reference network would also change with them. With real time inputs, it is possible to form a reference network for every eventuality in the system in real time, and carry out quick analyses based on these smart reference networks, and offer real time dynamic network pricing.