Hydroelectric Power Research Articles

Evaluating environmental impacts of micro, mini and small hydropower plants in Norway

Small-scale hydropower plants with an installed capacity <10 MW are an important part of Norway’s local and regional development. Small-scale facilities have been viewed as a relatively environmentally friendly form of energy production because they are assumed to have limited negative environmental impact. However, the plants potentially have environmental impacts related to land use changes from infrastructure installation and also instream effects such as barriers to fish migration or disturbed flow conditions within bypasses. We used a remote sensing and GIS approach to examine the relative environmental impacts of three different size classes of Norwegian small-scale plants – categorized as micro (< 0.1 MW), mini (0.1 – 1 MW) and small (1 – 10 MW). We evaluated 148 small-scale hydropower projects in Trøndelag, central Norway, focusing on their footprint and potential environmental impacts. Our analysis showed a slight preference for siting in forested habitat and, in particular, forested gorges associated with high biodiversity. However, most hydropower plants were not sited in forested gorges, or in areas with high predicted intensities of threatened terrestrial species. Similarly, there was little overlap with known migratory paths of Atlantic salmon and sea trout, or with archived occurrence records of instream fishes: salmon, trout or European eel. A low degree of overlap was attributed to the limited number of projects compared to the extensive distribution of these fish populations. The footprint areas of the projects were small (< 4 ha) but increased with the size of the hydropower plants. Individual micro plants likely had low impact within their footprint because they required the least infrastructure for installation, and lacked dams which may act as barriers to fish movements. However, small plants were more land-use efficient. Our findings suggest that all size classes of small-scale hydropower plant have a role in balancing Norway’s goals of minimizing environmental impacts of energy production while contributing to local and regional development.

Methods to prevent or mitigate total dissolved gas supersaturation in the waterways downstream hydropower plants

Abstract Downstream hydropower plants, a change in water chemistry can lead to the occurrence of a widely unknown problem: total dissolved gas (TDG) supersaturation. It takes place when air is entrained in a water body and exposed to high pressures, which leads to gas dissolution in the water. Re-exposure to atmospheric pressure downstream the power plant results in TDG supersaturation. This is a potential danger for the aquatic environment living in these waters, as the increased saturation poses the risk of experiencing gas bubble disease (GBD). Studies about TDG supersaturation are found in North America (USA and Canada), China, Brazil, and Norway (minor studies include Austria, Germany, and Sweden). Yet, knowledge about the risk of the problem is not widespread, which leads to the repetition of mistakes. Moreover, shifting precipitation patterns induced by climate change are expected to lead to an increase in TDG supersaturation occurrences, as those are associated with flooding. An overview of methods to either prevent or mitigate the problem of TDG supersaturation downstream hydropower plants is presented and recent study results are disseminated. These include civil engineering, operational, and technical methods. Where hydropower plants are in a planning phase, this can contribute to preventing the occurrence of TDG supersaturation in the first place, while existing hydropower plants can implement different measures to reduce the risk of producing TDG supersaturation in the downstream waterways. This helps maintain the aquatic environment as well as local habitat for fish and invertebrates, and therefore counts towards hydropower taxonomy and increases social acceptance of hydropower.

Monitoring and system estimation tool for a hydro power plant in automated islanded grid operation for emergency power supply

Monitoring and system estimation tool for a hydro power plant in automated islanded grid operation for emergency power supply

Investigation on Machine learning based fault detection and estimation in hydro turbines of industrial hydro power plant

Investigation on Machine learning based fault detection and estimation in hydro turbines of industrial hydro power plant

First results of soil and water bioengineering interventions to stabilise and control erosion processes in hydroelectric power plant reservoirs in Brazil

Reservoir banks are highly susceptible to erosion processes that result in a loss of stability. The main factors that cause erosion on reservoir banks are wave action and the oscillation of the water level. The aim of this study was to investigate four different soil and water bioengineering measures to stabilise and control erosion processes on the banks of reservoirs. The selection of plant species must follow various technical and ecological criteria. The study area is located at Itá hydropower plant. The development of the techniques and the used plants were monitored over a period of 28 months. Permanent plots were installed to assess plant development and erosion. When combined with support structures, the plants used were able to develop well. The average diameter and height of the plants increased in all sections. For the average plant height after 5 months, the best results were obtained in section A (1.32 m), and after 28 months the plants in sections C and B had an average height of 2.05 m and 2.01 m respectively. The greatest deposition occurred within the intervention zone, ranging from −6.4 cm/year (section A) to −0.6 cm/year (section D). For the pins 3/7, the largest soil deposition occurred in section B (−3.4 cm/year), while a soil loss (0.1 cm/year) was measured in section C. This confirms the positive technical effect of inert structures in combination with plants. The structures combined with vegetation, creates a barrier effect that protects the shore and enables the deposition/retention of sediments.

PROSPECTS FOR OBTAINING GREEN HYDROGEN AT MINI-HYDROELECTRIC POWER PLANTS FOR TRANSPORT

The use of hydrogen transport is an important step towards carbon neutrality. Unlike traditional transport running on hydrocarbon fuel, hydrogen cars do not hurt the environment during their operation. New green technologies for public transport deserve special attention since they are a key source of pollution in large cities. Achieving carbon neutrality is impossible without using new hydrogen technologies in all industries. Hydrogen, in its final form, should become the main fuel for transport (cars, buses, trains, and river vessels), which, unlike electric transport, is not limited by the speed of refueling.Hydrogen energy in the process of its development faces a large number of tasks and challenges, such as the production of "environmentally friendly" hydrogen, namely "green", which is in greatest demand during the transition to a carbon-free economy, as a result of the problems arising during the storage of hydrogen.Russia has huge water resources and one of the promising, energy-efficient and economically inexpensive technologies is the production of hydrogen fuel at hydroelectric power plants. This study presents a scheme for producing green hydrogen at a mini-hydroelectric power station with subsequent use for public transport purposes. In the Russian Federation, various domestic companies are developing and designing hydrogen-fueled transport. In the near future, hydrogen public transport may become a good alternative to diesel buses.

The role of hydropower on energy market: a comparative study in four EU countries

Abstract The development of energy prices over time has depended on several factors. Difficulties and disruptions in local and global energy markets caused by climate change, pandemics and wars have accelerated the transition to clean energy. The overview of electricity generation in four countries (e.g. Lithuania, Italy, Iceland and Austria) is examined. The energy policy outlined in the REPowerEU program focuses on saving energy, producing clean energy and diversifying the energy supply at EU level and in the member states. However, more electricity production from non-dispatchable renewable energy sources has introduced a phenomenon of negative electricity prices, highlighting importance of energy storage. This paper focuses on the contribution that hydropower can bring to the energy market. Two contributions of hydropower assets are crucial in the European energy market for the regulation of the power grid. The flexibility and storage capabilities of reservoir and pumped storage power plants are unmatched by any other technology. These contributions of the hydropower sector to the energy market and the new challenges in the operation of hydropower plants are discussed involving critical analysis of four countries.

Spatial and temporal variability of physicochemical characteristics in Lancang River sediments amid hydropower development

The construction of river dams disrupts river continuity and sediment transport, altering the riverbed between sediment “sources” and “sinks” and changing the sediment characteristics of the river. In this study, 256 sediment samples from 54 major control cross-sections of the Lancang River (LCR) were analyzed to examine the spatial and temporal distribution of clay and non-clay minerals in the sediment and their relationship with the environmental changes caused by the construction 11 hydropower plants. The results indicate that the construction of terrace dams on the LCR interrupted the downstream refinement trend of sediments, which reappeared once the terrace reservoirs stabilized. Additionally, the interception of the dam increased the accumulation of clay mineral in sediments. From 2011 to 2023, the relative abundance of clay mineral in the regulated reaches (RRs) increased by 2.4 %, the quartz content decreased by 26.2 %, and the contents of calcite, mica, kaolinite, and chlorite increased, respectively. Consequently, the main non-clay mineral assemblage in the sediments shifted from quartz+feldspar to quartz+feldspar+mica. Furthermore, the clay mineral content was higher upstream the main dams (15.3 %) than downstream (14.8 %), with the sediment quartz and calcite contents being higher downstream, and mica and chlorite contents being higher upstream. The feldspar content showed a minimal change. However, the mineral composition of the sediments in individual reservoirs varied significantly, owing to the specific environmental conditions of each reservoir. The distribution of sediment clay also differed between the dry and rainy seasons. This study provides a scientific basis for managing reservoir sediment scheduling and regulating the ecological and environmental safety in watersheds.

Development of Portable Pico Hydro Power Plant for Low Head Applications Using Cross-Flow Turbine

The purpose of this research is to develop a portable Pico Hydro Power Plant (PHPP) using a cross-flow turbine type utilizing a head of less than 3 m with a target output electric power of 20 W which is sufficient for lighting or charging laptops and smartphones for activities in remote areas. Previous research has resulted in a prototype of a portable PHPP with a cross-flow type, but because the prototype construction was made using a 3D printing process; many obstacles were still encountered during manufacturing, installation, and testing. The development carried out in this study includes changes to the turbine housing, nozzle, outlet, bearing housing placement, and turbine runner. The resulting PHPP has advantages in simplicity in the manufacturing process, installation, and operation. Based on experiments or tests carried out at a head of 2.3 m, it shows that the electrical output power had met the output target of 20.5 W with a turbine efficiency of 39.6%.

A Milestone Vision on The Applied Methodologies for Concrete Dam Health Monitoring

This research reviews the applied various methodologies for concrete dams’ health monitoring and assessment. The main type of dams focused on this review is the embankment fill dams that serves as an important function in water supply, irrigation, and hydroelectric power. The emphasis is devoted on the integration and assessment of static and dynamic methods for dams monitoring in order to improve safety and increase the life span of dams. Static methods are usually monitor changes that are prolonged over time and are critical for the assessment of the enduring structural health. Whereas, dynamic methods are considered as real-time data crucial to address immediate changes in the environment and operation. Mathematical models and structural health monitoring techniques were surveyed that improves the encompass of hydraulic, thermal, crack, and time (HTCT) model for extreme conditions. In addition, the use of artificial intelligence (AI) was explored and particularly for internal erosion monitoring. Comparison of such analyses reveals that static monitoring is efficient in its approach to assessment over the long term, while dynamic monitoring performs better in coping with instant changes. Based on the review findings, therefore, it could be concluded that an integrated approach with the use of static and dynamic methods, supported by advanced computational models, would enhance the effectiveness of monitoring systems. The future work shall focus on the development of such integrated systems to increase the resilience of dam infrastructures, while the monitoring technologies have to be adapted continuously to the environmental challenges and the complexity of dam systems.

Techno-economic analysis of floating solar photovoltaic plant in reservoir-based hydropower station in India: a case study

ABSTRACT India's grid stability and sustainable energy transition encounter challenges posed by the unpredictable nature of solar power and the low plant load factor (PLF) of hydroelectric stations caused by water scarcity. It is worth noting that traditional energy sources still account for 78% of the country's energy demand. This study aims to present a solution to these problems by analysing the feasibility of a floating solar photovoltaic (FSPV) plant on the reservoir of Tehri hydro plant, Uttarakhand, India. The study determined that a 175 MW FSPV system has the potential to generate 298 million units (MU) of energy and reduce CO2 emissions by 265 million kg. The estimated increase in hydropower production by preventing water loss through evaporation amounts to 7.05 million units per year. The estimated tariff for the proposed 175 MW FSPV is 5.25 US Cents/Unit, in accordance with current regulations. In addition, the System Advisor Model (SAM) software calculates the net present value and payback duration of capital invested to be 18.05 million US$ and 8.8 years, respectively. The analysis also determined that there is no need for additional transmission infrastructure to evacuate FSPV power from the existing Tehri hydro plant. The proposed model of FSPV with hydropower stations enables the reservoirs to function as virtual batteries, hence optimising power generation. Furthermore, the viability of FSPV installations have been assessed at sixteen reservoir-based hydropower stations with a capacity factor less than 30%. Annually, installing FSPV systems at these locations may yield total power output of 11446 MW and generate 17310 MU of electricity. The integration of these sites would lead to substantial reductions in CO2 emissions, amounting to 15406 million kg, as well as an increase in hydropower generation by 341.30 million units per year.

Discrete Electronic Load Controller for minimizing Total Harmonic Distortion in Micro Hydro Power Plants

Discrete Electronic Load Controller for minimizing Total Harmonic Distortion in Micro Hydro Power Plants

Future cities and sustainable development: Integrating renewable energy, advanced materials, and civil engineering for urban resilience

This review focuses on the integration of renewable energy, advanced materials, and civil engineering to foster urban resilience in future cities. As urban populations continue to grow, the demand for sustainable solutions to mitigate environmental impact and enhance quality of life becomes increasingly urgent. This review explores how the convergence of renewable energy sources, innovative materials, and civil engineering practices can contribute to the development of resilient cities capable of meeting the challenges of the 21st century. The integration of renewable energy sources, such as solar, wind, and hydroelectric power, offers opportunities to reduce dependence on fossil fuels and mitigate greenhouse gas emissions. Advancements in renewable energy technologies allow for the generation of clean, reliable energy within urban environments, promoting energy independence and reducing carbon footprints. Additionally, the utilization of advanced materials in urban infrastructure can enhance durability, efficiency, and sustainability. Nanotechnology, for example, enables the development of high-performance materials with superior strength, flexibility, and resilience. These materials can be used in construction, transportation, and water management systems to improve infrastructure resilience and longevity. Furthermore, civil engineering plays a crucial role in designing and implementing sustainable urban infrastructure. From green building practices to resilient urban planning, civil engineers are instrumental in creating cities that can withstand environmental hazards and adapt to changing conditions. By integrating renewable energy, advanced materials, and innovative engineering solutions, cities can enhance their resilience to climate change, natural disasters, and other challenges. This review examines case studies and examples of successful integration of renewable energy, advanced materials, and civil engineering in urban development projects worldwide. It also discusses the challenges and opportunities associated with implementing these solutions, including technological barriers, financial considerations, and policy frameworks. The integration of renewable energy, advanced materials, and civil engineering is essential for building resilient and sustainable cities of the future. By embracing innovation and collaboration across disciplines, cities can enhance their capacity to thrive in the face of environmental, social, and economic challenges, ultimately improving the quality of life for urban residents while preserving the planet for future generations.

Dimensioning of a hybrid photovoltaic-electricity grid installation: Case of the computer rooms of the IST of Mamou, Guinea

The objective of this research is to propose a technical and economically viable solution to efficiently and sustainably power the computer rooms of the Higher Institute of Technology of Mamou using a hybrid photovoltaic-electric grid installation. This research will contribute to optimizing the use of solar energy and reducing electricity consumption from the grid, while improving the resilience and sustainability of IT installations. During this research, we used two (2) sizing methods, namely: the manual method based on empirical formulas and the method using HOMER software. These two methods led to several results, the main ones being: Concerning photovoltaic solar: one hundred and ninety-two (192) 500WC panels for an installed power of 96,000 WC; one hundred and forty-four (144) 200 Ah batteries for an installed capacity of 28,800 Ah; two converters (Sunny boy and Sunny Island) with a power of 107 kW each and the EDG electrical network of 29,604 kWh/year: The annual production of electrical energy of the entire hybrid system is 171,665 kWh, of which 29,604 kWh for the electrical network supplied by the Garafiri hydroelectric power plant (75 MW) for a voltage level of 110kV/30kV, or 13%. According to our analyses, this research shows that the use of renewable energy sources such as photovoltaic solar energy coupled with the electrical network via a hydroelectric power plant remains the best optimal solution for providing clean and less polluting energy to an isolated site in general and that of Guinea in particular, whose hydroelectric potential is estimated at 6000 MW and very considerable solar irradiation

A Poem on the Sea of Tears, or the Chronicles of a Disaster. Oleksandr Dovzhenko about Kakhovka Hydroelectric Power Plant

The article is based on the diary entries of Oleksandr Dovzhenko. The realities of the construction of the Kakhovka hydroelectric power station (1950–1956), which has become another stage of Stalin’s plan to “tame nature” are investigated in the article. As a result of thoughtless, ideologically driven decisions, irreparable damage has been done to Ukraine’s ecology, its demographic and settlement structure, cultural and historical heritage. On June 6, 2023, the dam of the reservoir has been blown up by Russian occupation forces, causing a global environmental disaster. In this regard, interest in the history of construction and true testimonies about that time has grown. Oleksandr Dovzhenko has worked here for five years to create a film about the man-made sea. Communication with construction workers, people who have been forced to move, losing their small homeland forever, enabled him to create his own chronicle of events in their artistic comprehension. The communist pathos of the diaries is caused by the artist’s passion for the idea of irrigating the arid steppes and, to a certain extent, the self-censorship of a person forced to survive under ideological and power pressure, which later gives way to doubts about the expediency of what is happening. A record on a sense of something terrible and inevitable that is about to happen appears. The writer witnesses a catastrophe, and eschatological plots of the destruction of the unique Ukrainian world unfold before his eyes. Three main themes on which the author’s attention is focused: nature, history, and people, are analyzed in the study. The loss of centuries-old natural landscapes (the Great Meadow), the flooding of thousands of historical monuments (Scythian burials, places of the Cossack Sich), the destruction of folk architecture, sacred buildings, farmlands, and broken human destinies have prompted O. Dovzhenko to search for options to prevent the disaster. His memoranda to the Council of Ministers and the Academy of Architecture have allowed him to add national color to the urban space of Nova Kakhovka, to mark the gates of the Kakhovka hydroelectric power station sluices with Cossack symbols – gull ships. The start of construction and the consequences it caused have led the artist to believe that it is inexpedient to continue building artificial reservoirs on the Dnipro. He has tried unsuccessfully to convey this idea to the specialists involved. Further experience has confirmed the truth of his conclusions. About 80 villages have been flooded again after the Kakhovka hydroelectric power station is blown up in 2023. After the water has receded, contrary to the pessimistic predictions of environmentalists, a willow forest has grown in this area within a year, and archaeological sites are once again on dry land. The first timid assumptions about the possibility to return the Velykyi Luh (the Great Meadow) have appeared. It seems that, following Dovzhenko, believing in the unconquerability of Ukrainianhood and the power of the national spirit, we can consider this a deeply symbolic phenomenon that gives us hope that all evil will be inevitably defeated.

Pressure Drop Analysis of Turbine Housing Model with Circular Sliced Pipe for Micro Hydropower Generation

Energy independence is a government program aiming to meet society's energy needs evenly. Steps to increase energy independence in the new and renewable energy sector include hydro-energy generation. One of the important components of a hydro generator is the penstock pipe and turbine housing, which channels water and then pushes and drives (spins) the turbine with the flow of water to produce electrical energy. The turbine housing flow design innovation must provide a function as an optimal fluid conductor by minimizing the resistance that occurs when fluid flows towards the turbine housing and rotates the turbine optimally. The scope of this research includes analysis of the phenomenon of energy loss flowing in circular pipe slices in hydroelectric power plant turbine housings with influencing factors such as friction, turbulence, and flow resistance, as well as measuring the pressure drop in circular pipe slices. The model developed is a circular slice bend with angles of 180 degrees, 270 degrees, 360 degrees, and 450 degrees, taking into account the optimal curvature ratio (R/D) of 3.5. Based on previous research, 90-degree wedge bends with many slices (n_(90-degree)) 4 to 6 or  4 and pressure drop coefficient (C_(pd-th)) obtained 180-degree (0.333 – 0.200), 270-degree (0.445 – 0.277), 360-degree (0.527¬ – 0.339), 450-degree (0.587 – 0.390) with a bend length L, an elevation reduction angle  and a 1.5D upstream-downstream elevation difference to avoid contact between the upstream and downstream bends. The results obtained from this research are the slice modules that can be used and the resistance coefficient values that arise from the slice modules. The more slices selected according to the angle of inclination chosen, the smoother the resulting circular bend shape and the lower the resistance value, but the work will be more difficult. The most optimal slice module is the number of slices that allow its implementation, and the resistance coefficient is small. By knowing the optimal resistance coefficient value, the resulting pressure drop can be predicted to maximize the thrust to rotate the turbine.

Predicting fine-scale downstream migratory movement of Atlantic salmon smolt (Salmo salar) in front of a hydropower plant

The Atlantic salmon (Salmo salar) is an iconic species of significant ecological and economic importance. Their downstream migration as smolts represents a critical life-history stage that exposes them to numerous challenges, including passage through hydropower plants. Understanding and predicting fine-scale movement patterns of smolts near hydropower plants is therefore essential for adaptive and effective management and conservation of this species. We present a spatially explicit individual-based model for predicting the movement of Atlantic salmon smolts in regulated rivers in Norway, parameterised for smolt movements in the River Mandal and the River Orkla. The model is rooted in statistically derived relationships between observed smolt swimming behaviour and the hydraulic variables they encounter. The aim of the model was to provide fast yet representative swimming patterns past hydropower plants, based on the hydraulic conditions experienced by the smolts. The model outperformed a ‘drift-only’ model in portraying observed swim tracks when comparing simulated and observed tracks. It was found to represent smolt swimming behaviour well. Our results show that by constructing swim models using relatively simple and general statistical relationships between smolt swimming behaviour and the hydraulic environment, we can produce fast and relevant outputs for an adaptive management process, aimed at exploring how physical implementations or changes in flow regulations might affect smolt populations.

DESIGN AND ANALYSIS OF HYDRO TURBINES FOR ELECTRICAL POWER GENERATION

In designing a hydropower plant, the design of turbine type depends on the head and water flow. Researchers suggest that Axial/Propeller turbines can perform efficiently in lower heads because of their high specific speeds, Francis turbines can perform efficiently in medium to medium/high heads with high water discharge and medium specific speeds whereas Pelton turbines can perform efficiently in high heads with low water discharge and low specific speeds. In this paper the output performance of Axial/ Propeller, Francis and Pelton turbines are designed, analyzed and compared using TURBNPRO software for the existing Jamshill Turen More HPP. The site head and water discharge are 117m and 305 m³/s. The feasibility recommends 4 vertical shaft Francis turbines. From the results we conclude that if a low head, high specific speed, Axial/Propeller turbine is designed for a medium head site, then its specific speeds exceed its limitations for the same electrical power output per turbine. Similarly, if a high head, low specific speed, Pelton turbine is designed for medium head site, then its runner diameter exceeds its limitations. Four Francis turbines can have the same electrical power output as a minimum of twelve Pelton turbines for the same medium head range

PROBLEMS OF CHEBOKSARY RESERVOIR AT PRESENT STAGE

The history of creation and development of Cheboksary hydroelectric power plant has always been of interest to researchers. The reservoir has been at a low level for many years. This condition results in numerous problems. The relevance of the study lies in the fact that currently the problem of the reservoir affects the interests of the population in three regions. The purpose of the study is to examine the problems of Cheboksary reservoir in the light of the economic development of the regions at present stage. Materials and methods. Various sources were used to work on the topic: archival documents, journalistic literature, articles in scientific journals and periodicals. The study was carried out using the comparative-historical method and the method of system analysis, which made it possible to generalize the data of sources and group heterogeneous judgments and assessments. Study results. In the 2010s, the Program of Comprehensive Survey of the Cheboksary Reservoir Zone was carried out. The survey revealed a number of problems related to the operation of the reservoir and the state of engineering protection. The Cheboksary hydroelectric complex is currently operated at an off-design level, in which the station does not produce electricity necessary for the economic development of the regions. In addition, there is a destruction of engineering protection facilities, territories and settlements are flooded, erosive processes are progressing, and water quality is deteriorating. Power engineers propose to solve this problem by raising the water level in the reservoir to the design level. However, not everyone agrees with this decision. Conclusions. There are various federal programs to improve the ecological condition of the reservoir and reduce its negative impact on the environment. The participation of municipal organizations in the programs has a positive effect.

Feasibility Study and Economic Analysis for Hydroelectric-PV Hybrid System Performed with PVsyst Software

While energy demand is increasing day by day with the developing technology, the decrease in traditional energy sources and the negative effects of carbon emissions on the environment encourage countries to turn to sustainable and environmentally friendly renewable energy sources. Requirements such as the periodic change of renewable energy resources depending on weather conditions and the optimum use of existing resources have made it attractive to use different renewable energy resources together. In this paper, the feasibility study of a hybrid energy system for Akfen Renewable Energy's Gelinkaya Hydroelectric Power Plant (HPP) with an installed capacity of 6,866 MW, located in Aziziye district of Erzurum province. In the study, the economic analysis of the hybrid model resulting from the integration of Gelinkaya HPP with SPP (Solar Power Plant) using PVsyst software is discussed. The acceptance of Gelinkaya HPP by the Ministry of Energy was made on June 14, 2013 and the power plant started electricity generation activities. Since this date, the average annual electricity generation value of the power plant has been 10.062.411 MWh and the capacity factor has been realized as 16.73%. With the analysis of the HPP-SPP hybrid system, it was observed that the power plant was able to generate an average of 12.491 MWh more electricity per year by contributing to electricity generation, especially during irrigation periods, and the capacity factor increased to 37.50%.