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The main focus of this paper is to address issues related with the impact of the small and medium size hydro power plants connected to the distribution network in Albania, respectively, to 35, 20, 10 and 6 kV distribution network. Considering the significant positive impact in generation they have had also an impact on the distribution system as far as the technical and financial aspects of the distribution network are concerned. The results of the analysis performed indicates that the Middle and South-East areas have been impacted from the deployment of hydro power plants in these area due to the increased power injected from these hydro power plants. Referring to the topology of the network, load demand, constrains and amortization of the distribution network, difficulties faced with the maintenance of the feeders and substations in the subject, this situation has created some problems and issues in respect of very high levels of the voltage in the substations during the minimum load consumption, overloaded of the distribution network as well as frequent outages of lines and feeders in some areas. The analyse performed supports the necessity of reinforcement of the network and the need of clear and strict rules to be followed in respect of connection point of hydro power plants into the distribution network, in order to guarantee a reliable and secured operation of the network and to contribute to the improvement of the performance indicators of the distribution network.

Utilization of microgrids is an integral part of the efforts for increased resiliency and deep integration of renewable energy sources in the power systems, as they allow maximization of the use of locally available resources and operational harmonization of internally interconnected parts of the power systems - either in grid-connected or island mode. Development of laboratory setups for studying different aspects of microgrids has been recognized as a valuable tool for preparation of the real-life implementation. In this paper we present a developed AC/DC laboratory setup that incorporates solar photovoltaic systems, battery energy storage, an electric vehicle charger, a small hydro power plant, electronically controllable loads, as well as resistors and inductors that replicate the topology of the CIGRE low-voltage distribution network. Harmonized operation of the elements of the microgrid is ensured by the implemented supervisory control and data acquisition (SCADA) system. To demonstrate wide potential of the developed setup, we present the results of several experiments in this paper.

To fulfil country’s irrigation and power requirements various large capacity dams have been constructed on major rivers in last 50 years. The long term sustainability of these structures is largely dependent on hydro-environment and the capacity of these structures to resist weathering action, chemical attack, abrasion, or any other process of deterioration. The concrete deterioration is directly influenced by various geographical, climatic and ecological conditions. The chemical reactions between cement and water enable the setting and hardening of cement, resulting in a binding medium for the aggregates and development of strength. Quality of water plays an important role in the production of concrete. There are some chemical environments under which the useful life of even the best concrete will be affected adversely. The aggressiveness of water is dependent on the pH value, the total dissolved salts, the degree of hardness, soluble chlorides, sulphates, carbonation, temperature and alkalinity etc. Understanding these conditions permit measures to be taken to prevent or reduce deterioration.

With the growing energy need, hydro power becomes the most outstanding source of renewable, clean and affordable energy. However, slurry erosion of underwater components reduce the overall efficiency of the power generating system, thus, fails to fulfil energy goals entirely. To prevent erosion damage, protective coatings are highly recommended. In present study, response of microwave cladding against slurry erosion wear is reviewed. The effects of process parameters such as microwave power and exposure time are discussed in detail. Microwave cladding of different material systems and their slurry erosion performance are also summarized.

Design and performance analysis of hydraulic turbines are two very crucial aspects of any hydro power project which ensure economical and efficient functioning of these plants. In this context, numerical hydrodynamic analysis of water turbines has been bringing revolutionary changes in the process since the last decade. In the recent years, advancements in computational resources have made the job quite easier and more reliable but brought new challenges as well. Appropriate use of various models and numerical solution schemes in order to capture different hydrodynamic phenomena is highly debatable, even today, due to the lack of generality and robustness. This paper illustrates various utilities of computational fluid dynamics (CFD) in simulating hydraulic turbine operations. The work is mainly aimed at critically reviewing various computational methodologies for achieving different objectives of hydraulic design and performance evaluation of water turbines. Regarding this, different objectives of computational investigations of hydraulic turbines such as derivation of performance characteristics, analysis of various unsteady phenomena, prediction and analysis of cavitation and determination of various losses are discussed in detail. A discussion on boundary conditions and turbulence modeling for capturing different hydrodynamic phenomena at design and off-design operations of hydraulic turbines is one of the major scopes of the paper. Also, various optimization techniques in combination with CFD for hydraulic performance optimization of the turbines are briefly discussed. This work is a dedicated attempt to bring various aspects of computational hydrodynamic investigation of hydraulic turbines on a single platform. Having done the extensive literature review of the CFD utilities for the turbines along with disseminating the best practices, certain research gaps and loose ends are identified and given as future scopes which are also the major highlights of the work.

Effects of human activities on the surrounding environment that lead to man-made disasters were studied. The main parameters of the cause of the accident on the scale of potential losses and hydroschemes were defined along with an estimation of the potential damage from possible accidents at hydroschemes caused by the release of the potential energy of water stored in reservoirs.

The negative environmental and social consequences of the major era of hydroelectric dam building in the 1950s and 60s generated social and political opposition to similar projects by the 1990s. In Ghana, hydroelectricity’s dependence on unpredictable rainfall also undermined the attractiveness of this source of electricity. The Bui Dam, Ghana’s third hydroelectric dam, faced considerable opposition until 2006, when the Chinese government loaned money for its construction. Gocking details how Chinese companies with similar funding, and constructing infrastructure projects in general in Africa, have contributed to a second era of major dam building in that continent, although there still remains considerable contestation.

This article discusses the design, organization of construction, installation and commissioning processes of the Los Caracoles and Punta Negra Hydro Power Plants (HPPs), as well as a plan for the development of the existing cascade of HPPs on the San Juan River in Argentina through the construction of the Tambolar HPP.

The paper presents the methodology for hydro power plants operation (Long-term and Short-term) in a hydro power cascade system. It includes water managing of generating and/or pumping units taking into accounts technical characteristics of the power plants facilities (turbine/generator and pump/motor systems), reservoirs characteristics considering all hydraulically connected infrastructures which are, as well as the hydrological conditions (for run offs and turbine inflows). The goal of the operation for all hydropower system is to have maximum profit from electricity production taking into account electricity market environment, power system requirements, as well as satisfying technical conditions and at the same time avoiding water spilling as it is maximum possible. Operating modes of the hydro power plants depend on electricity market price, tariff prices and time duration of each tariff (base, peak, and rush hour), technical characteristics of the unit(s), hydro technical conditions, water reservoir’s volumes, run off and others. The application of the model is presented with the results on real hydro power systems consist of different hydraulic connections in various cases depend on hydrological conditions and requirements. The model can be used to make preliminary analysis for additional improvement of hydro systems as having the results for additional installed power of the existing system. The selected output results are presented with appropriated comparing and at the end with conclusion remarks.

Integration of a grid with an under-developed remote hilly area faces various technical and geographical challenges. Thus, generation of power from renewable resources in off-grid conditions has become one of the most cost-effective and reliable solutions for such areas. The present research deals with the possible application of an integrated solar/hydro/biomass/battery-based system to generate power in autonomous mode for a remote hilly town of a northeastern Indian state. Four different cases of the integrated energy system (IES) were designed using the hybrid optimization model for electric renewable (HOMER Pro), examining the performance of each case. The best combination of the integrated system was chosen out of several cases depending upon the optimized solution that can meet the load demand of the proposed hilly town sustainably, reliably and continuously. The simulation results show that the integrated battery/biomass/hydro/solar-based system is the best optimized, cheapest and most suitable solution to generate renewable-based power for the specified location, having the lowest net present cost (NPC) of USD 644,183.70 with a levelized cost of energy (COE) of 0.1282 USD/kWh. Further, the result also indicates that the optimized configuration reduces the emission of CO2 gas in the environment compared to the battery/biomass/hydro system having the worst emission rate. A sensitivity study was also carried out with variation in load, hydro stream flow and solar irradiation, respectively that may largely affect the technical as well as economical aspect of an integrated energy system.

This paper presents a discussion on Quebec’s pegmatite lithium resources and potential markets. It also evaluates the opportunities of lithium battery production for electric vehicles (EV) in the province while reducing greenhouse gas emissions. The paper shows that mining Quebec’s lithium ore deposits would be sufficient to satisfy the province’s lithium demand and also for exporting abroad lithium-ion batteries. By considering only the projects whose final product is LMH or LCE, Quebec would be able to produce between 10 and 21 million lithium-ion batteries for electric vehicles with a greenhouse gas emissions footprint of only 43% of the international average value due to Quebec’s hydro power. Finally, considering Quebec’s lithium mining project economics, the increased future demand for lithium would render Quebec’s lithium pegmatite projects competitive compared with those reported for brine projects.

The average depth of Yamansu hydropower station foundation pit is 70 m. The foundation pit was excavated with five-level slopes. The lowering of groundwater level is significant for excavation. Drainage and pumping were adopted in dewatering. Pumping tests were performed to reverse hydraulic parameters and calibrate numerical models. Numerical simulations were performed to evaluate the dewatering scheme. In the first stage, powerhouse tailrace canal was excavated and utilized as a drainage channel to lower the groundwater level. The drawdown and hydraulic gradient were evaluated to prevent potential water inrush, erosion, piping, and slope failure. In the second stage, cutoff wall and pumping wells were evaluated to lower the groundwater level. The influences of depth, permeability, and thickness of the cutoff wall were evaluated. Dewatering scheme was revised accordingly based on the evaluation. The optimized dewatering scheme, which can be referred by similar engineering, was performed and verified successfully.

This paper proposes a novel 1D-3D approach for the stability characteristics of the hydropower generation system (HGS) in transition processes. First, a 1D-3D coupling model was established for the HGS in the load-reduction process. Second, a sensitivity analysis of the HGS’s parameters to the rotation speed and discharge was conducted. Third, the pressure pulsation characteristics of the HGS with three typical guide vane openings were analyzed during the load-reduction process. The results show that with the closure of the guide vane, the discharge gradually decreases and it is sensitive to the change in hydraulic parameters. The rotation speed fluctuates at the early stage of the transition process and is easily affected by mechanical parameters. In addition, the pressure pulsation inside the Francis turbine is more intense under small openings than large openings, and the primary frequency of pressure pulsation under three opening degrees is the blade frequency. The 1D-3D coupling model successfully integrates the advantages of traditional methods and provides a reference for predicting system stability and exploring the stability mechanism.

Renewable energy, is the primary load bearer of a sustainable circular economy and hydropower being one of the earliest forms of it, has a wide application base. With unprecedented situations being faced by the people every day, power consumption patterns and requirements are changing and so are the faces of the leading economies. However, like other renewable strategies it is assayed based on the greenhouse gas emissions during its operation. This unfortunately presents a true but blurry picture. Some of the long-term issues with creating a dam, are soil quality degradation in downstream regions, loss of aquatic life due to high-speed turbine blades, disbalance in the nutrient cycle of aquatic systems, water contamination with machinery oils, displacement of local communities, loss of soil fertility near the site due to drilling and tunnelling, landslides and seismic issues due to excavation of land which loosens the nearby soil cover. Therefore, our goal is to analyze and compile various case studies of hydro power projects throughout the globe which caused some environmental or social disruption in their respective regions and the various steps that were taken by the government or the locals to tackle these problems. Many areas faced seismic problems, environmental degradation, water profile alterations and social displacement. But, by opting for new turbine technologies, fish friendly channel designs and landscaping procedures featuring indigenous vegetation to restore surrounding ecology, those regions were able to amend the problems with their hydropower project.

В горных реках Северного Кавказа расход воды в паводок увеличивается в десятки раз. Часто в горных условиях технически проще и дешевле построить не плотинную станцию с большим водохранилищем, а деривационную ГЭС с небольшим водохранилищем или с бассейном суточного регулирования. Горные реки несут большое количество песка и ила. Во время паводков вода переносит и мелкие камни, и гальку. Если не принимать мер для очистки от речных наносов водохранилищ, то через несколько лет полезный объем водохранилищ будет исчерпан. В статье рассматривается один из способов поддержания водохранилищ и бассейнов суточного регулирования в рабочем состоянии. Предложено речные наносы (аллювий) регулярно извлекать из водохранилищ, обрабатывать и использовать как сырье для производства строительных песчано-гравийных смесей и щебня. Есть большая потребность в этих материалах при строительстве автомобильных дорог, в промышленном и гражданском строительстве. Одновременно можно использовать тонкие фракции аллювия в виде ила, глины и тонкого песка в качестве основы для приготовления почвенного субстрата с целью применения его для улучшения пойменных земель. Обсуждаются вопросы организации при водохранилищах каскада ГЭС на горных реках механизированных участков по утилизации донных отложений. In the mountain rivers of the North Caucasus, the water discharge during a flood increases tenfold. Often, in mountainous conditions, it is technically easier and cheaper to build a derivation hydroelectric power station with a small reservoir or with a daily regulation pool than a dam station with a large reservoir. Mountain rivers carry large amounts of sand and silt. During floods, the water carries lots of small stones and pebbles. If no measures are taken to cleanse reservoirs from river sediments, their useful volume would be exhausted in a few years of operation. The article discusses one of the ways to maintain reservoirs and basins of daily regulation in working order. It is proposed that river sediments (alluvium) be regularly removed from reservoirs, processed and used as raw materials for the production of construction sand and gravel mixtures and crushed stone. The demand for these materials in the construction of highways, in industrial and civil construction is high. At the same time, it is possible to use fine fractions of alluvium in the form of silt, clay and fine sand as a basis for preparing a soil substrate to improve floodplain lands. The issues of organizing mechanized teams for utilization of bottom sediments at reservoirs of a cascade of hydroelectric power stations on mountain rivers are discussed.

A question of local sources of carbon dioxide have considered in this work that were detected during of tunneling of water-supply tunnel of Lukhuni hydго power. This event led to the termination of tunnel works, since formed an unfavorable environment for breathing and have had poisoned staff. As a result of various measurements of carbon dioxide concentration was varied in the range of 4.5-5.5%.

This paper describes the design and development of a test rig, for the experimental assessment of performance characteristics of thrust bearing used in hydro power plants. This test rig has features to study experimentally the conventional pad-based thrust bearing and the newly designed water cooling enabled pad. In this paper, a cooling circuit designated as Circuit-I has been installed and then testing is performed. The shaft speed and axial load has been set at 1400 r/min and 5.0 kN. The lubricating oil used SAE-30 and inlet temperature of oil was maintained at 40℃. The main focus of the present work is to compute the influence on the temperature distribution in the oil film on the top surface of the pad with the embodiment of cooling circuit arrangement. From the experimental results, the overall reduction in the oil film temperature or on the top surface of the pad has been found to be 14% when the conventional thrust bearing set up is replaced by water cooling enabled pad of this kind.

This paper evaluates performance indices based on industry-wide practice and suggests possible approach for improving the operational efficiencies of Jebba, Kainji and Shiroro hydro power generating stations. To actualize that, data including average daily gross operating head, daily flow rate and daily energy generated were obtained from Jebba, Kainji and Shiroro power stations and the National Control Center (N.C.C.) Osogbo. From the energy (MWh) generated the average daily power generated (MW) was computed. Consequently, the average operational efficiencies of Jebba, Kainji and Shiroro hydro schemes were evaluated and found to be 89.43%, 88.45% and 94.03% respectively. Similarly, performance indicators including deemed generation, auxiliary energy consumption, availability factor, capacity index, workforce deployment, forced outage factor and scheduled outage factor were evaluated and technical inferences made. The study was limited to the year 2010 due to non-availability of data for other years.

Development in Africa is undergoing an infrastructure turn, no more so than in resurgent dam building. But how are new projects planned and constructed? Are we seeing the repetition of much maligned practices that underestimated economic, environmental and social costs, or have past critiques changed infrastructure building in the twenty-first century? Using the concept of the technician’s realm that describes short-sighted and expert-centric twentieth century practices of dam building, this article analyses the incorporation of reformist ideas about knowledge production, mitigation and compensation. It uses a detailed case study of the Rusumo Dam, and examines the decision-making processes of the World Bank and a new dam-building organisation, Nelsap. Significantly, this case involved a marked design revision to reduce impact, but also top–down and depoliticising impact assessment and policymaking. It therefore demonstrates nuanced change in the infrastructure turn, the incorporation of reform and continued relevance of past critiques.

In the hilly regions of India, hydro power potential is available, but it is not completely utilized for power generation till date due to the unavailability of proper electrical structure....

This paper reviews motivations and solutions for variable-speed operation in large hydro power plants with a special emphasis on full-size converter operated synchronous generators. First, the established concepts of conventional pumped storage power plants are briefly described. Then, the implemented applications with use of power converters and synchronous machines in hydro power plants, their power ratings, power converter topologies used, and the experiences obtained during operation are reviewed. Concerning its state-of-the-art position in variable-speed pumped storage power plants, the variable-speed capability offered by doubly-fed induction machines is also briefly described, including the power range that can be achieved in pumping mode as well as the power converter ratings of existing power plants. Following this comprehensive analysis, this paper identifies the requirements of today’s power converters and synchronous machines for utilization in large pumped storage power plants as full-size converter operated synchronous generators. It analyzes the design implications on the electric machines driven by such converters, and investigates the advantages of the additional possibilities given by the full-size converter operation that may outweigh the added cost, system complexity, and power loss.

Most prime movers have vibrational problems due to the inherent unbalance due to some reason or other, the mass centre of the rotor does not coincide with the geometrical axis of the shaft known as...

This paper analyzes the application of moment-SOS (sum of squares) relaxation to solve the medium term hydrothermal dispatch (MTHD) problem for predominantly hydro systems. The optimal dispatch is formulated as a two stage stochastic programming problem, which is nonconvex due to constraints that represent hydro power production, and may have multiple solutions. The size and conditioning of the problem pose challenges to the use of the semidefinite programming (SDP) techniques that are discussed in the text. The size of the problem restricts this study to first order moment relaxations. Therefore, to improve the quality of relaxed solutions, additional meaningful constraints are introduced in the SDP problems. Subsequently, the problem re-scalded to achieve numerical stability in SDP relaxation. Results obtained for different test systems, most of them being partitions of the Brazilian hydroelectric system, indicate that the procedures used to improve the quality of SDP solutions are effective.

The design of load frequency control (LFC) for the hydro-hydro power system suffers from poor dynamic performance owing to large time constants associated with hydro power generations. The dynamic ...

The Zambezi River Authority which manages and operates the Kariba Dam complex on behalf of the Governments of Zambia and Zimbabwe, is currently financed through direct disbursements from the two countries. This was a transitional agreement entered into at the dissolution of the Central African Power Corporation, the predecessor to time Zambezi River Authority. To move away from direct disbursements and with the prevailing privatisation, it was prudent for the Authority to work out a mechanism to raise finances through tariffs, fees and other charges for the services provided. In this light the Electricity Utilities have to pay for the water used in power generation. The manner in which the finances are raised is the subject of this paper. An integral part is the discussion of the concept of water banking and how this can be applied at Kariba by the two national Electricity Utilities.

This study examined impact of climate variability on reservoir-based hydro-power-generation in Jebba dam, Niger State of Nigeria. Data of rainfall, temperature, evaporation, reservoir inflow and outflow and power output for thirty-one years were obtained from Jebba Hydropower Station [JHP]. The Man-Kendall and Pearson’s Product Moment Correlation Coefficient (PPMCC) were used to establish the influence of weather parameters on the reservoir inflow and outflow. Findings showed increased electricity generation during dry season than wet season. The highest annual mean amount of the electricity generated was in 2016 having mean of 689.12mwh, dry season (352.26mwh) and wet season (336.86mwh). Reservoir inflow showed negative trend with severe fluctuations in 1998 (1436.42M3/Sec), 1999 (1581.08M3/Sec) and 2010 (1641.08M3/Sec) with steady increase in 2016 (1556.0042M3/Sec), 2017 (1556.4242M3/Sec) and 2018 (1635.7542M3/Sec). The reservoir outflow pattern showed tremendous and negative trend in fluctuation with increase in 1998 (1421.75M3/Sec) 1999 (1581.58M3/Sec) and 2010 (1641.16M3/Sec) and a steady increase in 2016 (1535.00M3/Sec), 2017 1558.83M3/Sec and 2018 (1632.00M3/Sec). Thus, rainfall and reservoir inflow had strong relationships with the amount of power generated than temperature and evaporation. Therefore, the government should increase the water carrying capacity of the reservoir construction by storing water to be used during dry periods.

The Russian electric power complex operates mini hydroelectric power plants with installed capacity up to 5 MW. The quantity and installed capacity of such power plants are not significant, but they, along with large power plants, perform the function of ensuring reliable power supply to consumers in regional power systems or in remote areas.

In today's world, large scale hydroelectric power plants have an impact in the energy demography; although, the huge potential of pico, micro and mini-hydropower plants are still very much untapped. In this work, a techno-economic viability, of mini hydro power potential from drainage water, has been investigated in four areas of Dhaka city. Considering the head of water fall and the flow rate in the drainage system, technical, economic and environmental parameters are studied. 100 kW to 500 kW power can be generated from the proposed system with economic benefit of around BDT 3. 9M to 28M per year, and emissions reduction of around 500 to 3000 ton- CO2/year.

This chapter research at the sharp expansion that renewable and intermittent sources have been promoting in electrical systems worldwide. In Brazil, a country with unique characteristics with a high degree of renewability due to the marked presence of water resources, the scenario is no different. Although these sources are marked by desirable attributes such as low operating cost and low impacts, their intermittence causes a series of difficulties that must become obstacles to unlimited expansion, as advocated by some actors in the environmental movements. The chapter summarizes the main points of difficulties and highlights from the international experience that there are limits that should restrict this expansion until a penetration of the order of 30% of the installed capacity of generation. This scenario may change in the meantime due to the greater presence of storage systems (possibly provided by the scale of penetration of electric mobility equipment and batteries), as well as in the Brazilian case if the environmental licensing conditions for the construction of hydroelectric plants with reservoirs could be changed to a more flexible level, so the Hydro power plants could function as large storage systems. It should be noted however that this hypothesis is today outside the context of Brazilian electric sector planning.

The main objective of this paper is to study the variations of the different parameters included in the tariff regulations of the Large Hydro Power Generating Plants. The data from various sources, primarily found on the central government site CERC has been carefully segregated, recorded and further partitioned into five sections based on their practical and mathematical applicability, namely Returns and Interests, Expenses, Depreciation, Auxiliary Consumption and Transmission Norms. The tariff regulations considered under this project are CERC 2004, CERC 2009, CERC 2014, CERC 2019, APERC 2017 and RERC 2019. The data from individual states, depending upon their availability, have been recorded in a similar manner, respectively. They were plotted graphically and tabulated to generate a detailed analysis of their trends and the differences were provided for better understanding and the preemptive prediction of the same parameters.

This paper deals with uncertainty and economical risks in hydropower projects. It discusses the different items that influence the economics of a hydropower project and the uncertainty each item (ie. dam, power house, etc) is burdened with. Different methods for assessing the uncertainty associated with each item, and their influence on the overall project uncertainty are discussed. The use of Monte Carlo simulation for computing risk is illustrated with an example.

this paper considers possibility of conducting unusable volume of energy generated by hydro power stations of Angara-Yenisei cascade during high water from years to energy system of European part of Russia and estimates possible quantity of energy and capacity conducted noting carrying capacity of inter-system power lines.