Hydroelectric Production Research Articles

Spatial distribution and interactions between mosquitoes (Diptera: Culicidae) and climatic factors in the Amazon, with emphasis on the tribe Mansoniini

This work aimed to evaluate the spatial distribution of mosquitoes in different seasonal periods and the interaction between climatic factors and the abundance of mosquitoes, especially those belonging to the tribe Mansoniini in the area surrounding the Amazon hydroelectric production region (Jirau-HP) of Rondônia state, Brazil. Mosquito specimens were collected in May, July, October, and December 2018, and April, July, September, and November 2019, over periods of three alternating days during the hours of 6:00 p.m. to 8:00 p.m. Mosquito sampling was performed using automatic CDC and Shannon light traps. Canonical correspondence analysis (CCA), combined with Monte Carlo permutations, was used to evaluate the correlation between climatic variables and species distribution. In addition, non-metric multidimensional scaling (NMDS) was used to verify the similarity among the sampled communities from the different collections. After analyzing the total mosquito fauna at all sampling points, 46,564 specimens were identified, with Mansonia dyari showing the highest relative abundance in 2018 (35.9%). In contrast, Mansonia titillans had the highest relative abundance in 2019 (25.34%), followed by Mansonia iguassuensis (24.26%). The CCA showed that maximum temperature significantly influenced the distribution of mosquito populations in the study area (p = 0.0406). The NMDS showed that sampling carried out in the rainy and dry seasons formed two distinct groups. There was a significant correlation between species richness and cumulative precipitation 15 days before the sampling period (R2 = 58.39%; p = 0.0272). Thus, both temperature and precipitation affected mosquito population dynamics. The effect of rainfall on mosquito communities may be due to variations in habitat availability for immature forms.

Amazonian socio-environmental frontier: struggles, resistance and contradictions in confronting the agrarian extractive frontier

Considering the advancement of the agrarian extractive frontier in Brazil, the research question was ‘what were the elements that enabled the formation and resistance of a socio-environmental frontier in the Amazon’? This extractive frontier has been related to the deforestation and environmental degradation caused by the expansion of predatory activities (logging, extensive cattle ranching, soybean cultivation, mineral extraction and hydroelectricity production), aggravating rather than mitigating climate change. The socio-environmental frontier has been created by the convergence of a diversity of experiences and fronts of struggle resisting the agrarian extractive frontier. Answering the question, the objective is to understand the main fronts of struggles, referred to as the environmentalist, peasant and Indigenist fronts. These fronts established the socio-environmental frontier, leading to the creation of protected territories, including Indigenous lands, extractive reserves and conservation units for sustainable use. It achieved recognition and international support, including financing of projects for protecting and consolidating such territories. Despite these conquests and victories, one cannot ignore the challenges and risks of the Amazonian communities becoming trapped by the logic of accumulation. The increasing demand for natural resources could disconnect them from the fundamental elements of their identities and connections to their territories.

Does hydropower production influence agriculture industry growth to achieve sustainable development in the EU economies?

There are many advantages of the hydropower industry, as an environmentally friendly resource, and also some challenges that need to be overcome to fully exploit this sustainable and renewable natural resource. The primary objective of this study is to find out the impact of hydropower factors and economic growth on the agriculture industry output among the EU27 nations within the time factor 1990 to 2021. Adopting the autoregressive distributed lag (ARDL), the findings show a significant positive effect could occur in agriculture industry growth of the European Union (EU13)-emerging economies using hydropower factors than in EU14-emerged economies. On one hand, among additional factors, economic growth and institutional quality contribute more positively to agriculture growth in EU13 economies than in EU14 economies. On the other hand, population density contributes more negatively to agriculture growth in EU13 economies than in EU14 economies. The findings show there can be a positive significant growth increase in the EU13 agriculture industry using fossil fuel output than in EU14 economies. The results show that growth could be sustained in the agricultural industry of the European nations by increasing the level of hydropower production as this will help in attaining sustainable development by the year 2030. This will therefore help in mitigating the effect of climatic changes due to environmental pollution. The projected calculations were seen to be reliable and valid and this was attested to by the three estimators used in the study (pooled mean group, mean group, and dynamic fixed effect). This study recommended that European nations could leverage hydroelectricity to achieve sustainable growth and development. The legislative arms of the government of these European nations should as well show more interest in green energy to achieve security and sustainable development in hydroelectricity production. Decision-makers in the EU nations should buttress more emphasis on sustainable means through which hydropower could be used to attain sustainable irrigation systems for the agriculture industry and thus minimize the demand for fossil fuels and reduce CO2-related emissions in the future tine ahead.

Risk of Climate Change for Hydroelectricity Production in China Is Small but Significant Reductions Cannot Be Precluded for More Than a Third of the Installed Capacity

AbstractTo support the implementation of China's carbon neutrality target, this study assesses the impact of future climate change on hydroelectricity production (HP) in China. We developed a hydropower database for mainland China, which covers 92% of the installed capacity indicated by national statistics (352 GW in 2018). An HP model was applied to simulate monthly HP by 3,521 conventional plants at different levels of global warming (1°, 1.5°, 2°, and 3°C above preindustrial) using an ensemble of monthly streamflow time series computed by five global hydrological models (GHMs), where each global hydrological model was driven by four global climate models (GCMs). With a probability of 80%, limiting global warming to 1.5°C will constrain changes of national HP to the range of −1.4%–2.5% as compared to near‐present climate (1°C). In case of a 3°C world, this range more than doubles. HP is projected to likely increase in the two provinces Sichuan and Yunnan that encompass more than half of China's installed capacity. However, with a probability of about 10%, HP may decrease in a 3°C world by more than 15% in five provinces, and 40% of the installed capacity may suffer from an HP decrease of more than 5%. The uncertainty of projected HP changes is mainly due to the GCMs. We found that relative changes in annual HP and streamflow often differ in magnitude and direction as HP depends on seasonal streamflow patterns and installed capacities that determine the maximum flow through the turbines.

Econometric analysis of pricing and energy policy regulations in Japan electric power exchange spot market

This study aims to provide a quantitative overview of the energy policy regulations concerning the Japan spot market liberalization and analyzes the market clearing price (MCP) and the regional spot prices based on the hourly contribution of the supply stack mix and the merit order effect. In addition, it estimates the regional spot prices interdependency on the MCP. The study acquires an hourly dataset in panel data format from 2016 to 2020 with total observations of 438,240 data records. The developed econometric models include panel data regression using fixed-effect estimator, ordinary least square, and two-stage least square equations. From the results, a one GWh addition from nuclear, hydroelectric, geothermal, biomass, solar, or wind power production technologies decreases spot prices. Contrarily, adding one GWh from thermal, hydroelectric storage, or regional interconnections raises the spot prices by 27.4, 606, 103 ¥/MWh, respectively. The spot prices of Hokuriku and Chugoku tend to offset the price spikes in Kansai, while Tokyo and Tohoku spot prices are significantly related. Adding one ¥/kWh to Tohoku spot price is estimated to raise the MCP by 0.35 ¥/kWh, while the addition of one ¥/kWh to Tokyo spot price is estimated to increase the MCP by 0.04 ¥/kWh. Furthermore, Kyushu and Tohoku, followed by Chubu, have appreciable control over the MCP. The study further highlighted policy implications to constrain the applications of hydroelectric storage as the costliest solution to balance the intermittency of renewable energy sources.

Remote sensing and in-situ approach for investigation of pelagic communities in the reservoirs of the electrical power complex.

Two closely located reservoirs on the Southern Bug River and its tributary in the southern region of Ukraine were compared to study the impact of temperature on hydrobionts and pelagic communities, a major ecologic issue in the climate warming context, using in-situ and satellite remote sensing data. These reservoirs are parts of the South-Ukraine electric power-producing complex. The Tashlyk reservoir is a cooling reservoir for the nuclear power plant, and Oleksandrivske reservoir is used for production of hydroelectricity and irrigation. The cooling reservoir is replenished by pumping water from the upper part of the Oleksandrivske reservoir. The relationships of temperature, transparency, and distribution of phytoplankton and zooplankton communities were established based on satellite remote sensing data and in-situ during 2013-2021. The main variables of phytoplankton and zooplankton were compared, and for improved understanding features, spatial distribution maps were created. It was found that the distribution of coenotic groups of phytoplankton and zoonplankton in the cooling reservoir (Tashlyk) corresponds to thermal conditions. Three communities of phytoplankton and two communities of zooplankton were identified in the Tashlyk reservoir. However, in the Oleksandrivske reservoir, separate communities of phytoplankton and zooplankton were reported along its length. It was shown that both on land and in the Oleksandrivske reservoir, there is an increase in temperature in summer, an increasing trend in the global warming context, but that was not observed in the cooling reservoir of the nuclear power plant (NPP). It let us assume that the factors such as temperature or nutrients impact can be assessed as external significant factors related to the catchment area for the reservoirs with different types of using.

A two-layer control architecture for operational management and hydroelectricity production maximization in inland waterways using model predictive control

This work presents the design of a combined control and state estimation approach to simultaneously maintain optimal water levels and maximize hydroelectricity generation in inland waterways using gates and ON/OFF pumps. The latter objective can be achieved by installing turbines within canal locks, which harness the energy generated during lock filling and draining operations. Hence, the two objectives are antagonistic in nature, as energy generation maximization results from optimizing the number of lock operations, which in turn causes unbalanced upstream and downstream water levels. To overcome this problem, a two-layer control architecture is proposed. The upper layer receives external information regarding the current tidal period, and determines control actions that maintain optimal navigation conditions and maximize energy production using model predictive control (MPC) and moving horizon estimation (MHE). This information is provided to the lower layer, in which a scheduling problem is solved to determine the activation instants of the pumps that minimize the error with respect to the optimal pumping references. The strategy is applied to a realistic case study, using a section of the inland waterways in northern France, which allows to showcase its efficacy.

Nehru’s Vision of Swaraj and Socialism

The thought of socialism is an age old phenomenon in the human society. Its traces can be found in the writings of Greek philosophers like Plato and Aristotle. Shades of socialistic thoughts can also be discovered in the Santan Dharma scriptures, Islamic scriptures and the teachings of Jesus Christ. But it was only in the beginning of the 19th century that socialism as a political, social and economic philosophy gained momentum.
 Jawaharlal Nehru believed that no country or individual could develop much without social freedom and a socialist structure of the society and the state. The idea of socialism had been a constant thought in his mind since the pre-independence days. As an economic modernist of his times, Nehru believed in the development of large-scale industries, which he thought was the only key to overcome poverty in the country. Nehru’s concept of socialism was not merely a rigid theoretical doctrine. Theories when put to practice entertain pragmatic difficulties. When Nehru got the opportunity to apply his concept of socialism as the first Prime Minister of India, he had to confront with many complications. His idea of socialism was subjected to many changes looking to the vast population of India. A strict adherence to any doctrine may prove detrimental at times, more so in a country, like, India. Nehru, therefore, envisaged a policy of mixed economy, of course socialist in nature, which would be best suitable to the needs of the country. India has both a rural and an urban economy and what is required is a harmonious blend between the two for the growth and development of the country. The construction of a series of big dams for agricultural irrigation along with the production of hydroelectricity i.e. energy for industrial purposes reflects Nehru’s idea of drawing a balance between the two major sectors of the country. 
 What Nehru meant by Swaraj was not merely political freedom but beside political freedom it should include social and economic justice for the Indian masses. Independence should bring not only a change of the officials but should also bring a change in the fundamentals of the life of a nation.
 The year 1991 will always be remembered in India as a year which is witness to a drastic change in the Indian economy policy. This was the year when the Government of India drifted from Nehru’s policy of mixed economy and announced the new economic policy which consisted of a wide range of reforms. Thirty years have passed under this new economic system and now the time has come when we should evaluate and analyze how far this new approach has been beneficial to the country.
 Today, the country is face to face with innumerable problems; problems related to inflation, unemployment, caste, class and religious activism. The country needs to address these problems in a determined way before it is too late. I understand that the time has come when we need to once again look back to Nehru’s vision of Swaraj and socialism for a pragmatic solution to these problems.

The Mekong Subregional Cooperation Framework: A Geopolitical Dilemma and the Ways Forward

The Mekong Subregional Cooperation Framework:A Geopolitical Dilemma and the Ways Forward Charadine Pich (bio) In the current environment of regional security architecture dynamics, complex geopolitical dilemmas, and the congestion of subregional cooperation mechanisms, the Mekong is no longer just a river but also a core ground for competition in a broader context for power play among the major powers. Some observers have even highlighted that the issue of Mekong geopolitics could follow the trajectory of the South China Sea disputes in the near future if it is not taken seriously. For the riparian states of the Association of Southeast Asian Nations (ASEAN), successfully managing geopolitical contestation over the river and its resources is of critical importance. ASEAN and the Mekong: A Diverging Path? The Mekong River (known as the Lancang in China) begins in the Tibetan Plateau and passes through China, Myanmar, Laos, Thailand, Cambodia, and Vietnam before joining the South China Sea. The Mekong basin is one of the most biodiverse areas in the world, sustaining around sixty-six million people. This figure amounts to 10% of ASEAN's total population and includes "most of the population of Laos and Cambodia, one-third of Thailand's sixty-five million, and one-fifth of Vietnam's ninety million people."1 At stake in the river's management are issues such as water sharing, dams and hydroelectricity production, fisheries, irrigation, environmental conservation, and climate change mitigation. The ASEAN countries are mostly divided into two camps over issues pertaining to the river: mainland Southeast Asia and maritime Southeast Asia. States in the former put the Mekong River among their top priorities because of the river's importance to the livelihoods of their people as well as their vulnerability to changes in the water flow from upstream by virtue of residing in the Lower Mekong region. States in the latter group, on the other hand, do not have a share of the river and consider issues regarding [End Page 57] the Mekong not primarily as security concerns but more in terms of their technical and environmental aspects. The troubles over the Mekong River have been largely viewed through an environmental and socioeconomic lens and seen as affecting only the mainland countries of ASEAN rather than ASEAN as a whole. Hence, the river's linkages with the region's broader security and geopolitical considerations have been given less attention. In contrast, although not all ASEAN member states are claimants in the South China Sea disputes, this particular issue is largely considered a wider security dilemma in the broader region of Southeast Asia and beyond and a major threat to regional peace, security, and stability. Although it might not be entirely fair to compare Mekong geopolitics to those of the South China Sea, there is no better approach to understand the Mekong security dilemma than to look at it through that benchmark. The disputes have been widely regarded as an alarming security threat for all of Southeast Asia that could jeopardize regional peace and security if not cautiously monitored. This risk is due to the diverse military presence and, to a certain extent, the arms race surrounding the area. While the Mekong security dilemma has not yet warranted this same level of heightened concern, many regional analysts are cautious of unprecedented trends in the Mekong given the increasing involvement of external actors and development partners alike. The Mekong issue has not yet attained a regional status or posed "alarming" threats that encourage discussions at the regional level among all the ASEAN member states or priority placement on any existing ASEAN agenda. In fact, Vietnam tried to slot the Mekong agenda into the wider discourse within ASEAN platforms during its 2020 chairmanship but found "very limited success."2 In part, this omission was due to the Covid-19 outbreak, which disrupted traditional ASEAN practices and shifted regional attention to focus more on public health and economic recovery. Nonetheless, Vietnam's attempt to highlight the Mekong on the ASEAN agenda was met with reservations from both maritime and mainland members. The maritime ASEAN states see Mekong issues as only affecting the mainland states and thus believe they should be dealt with through existing frameworks at the...

Continuous Piecewise Linear Approximation of Plant-Based Hydro Production Function for Generation Scheduling Problems

An essential challenge in generation scheduling (GS) problems of hydrothermal power systems is the inclusion of adequate modeling of the hydroelectric production function (HPF). The HPF is a nonlinear and nonconvex function that depends on the head and turbined outflow. Although the hydropower plants have multiple generating units (GUs), due to a series of complexities, the most attractive modeling practice is to represent one HPF per plant, i.e., a single function is built for representing the plant generation instead of the generation of each GU. Furthermore, due to the computation time constraints and representation of nonlinearities, the HPF must be given by a piecewise linear (PWL) model. This paper presented some continuous PWL models to include the HPF per plant in GS problems of hydrothermal systems. Depending on the type of application, the framework allows a choice between the concave PWL for HPF modeled with one or two variables and the nonconvex (more accurate) PWL for HPF dependent only on the turbined outflow. Basically, in both PWL models, offline, mixed-integer linear (or quadratic) programming techniques are used with an optimized pre-selection of the original HPF dataset obtained through the Ramer-Douglas-Peucker algorithm. As a highlight, the framework allows the control of the number of hyperplanes and, consequently, the number of variables and constraints of the PWL model. To this end, we offer two possibilities: (i) minimizing the error for a fixed number of hyperplanes, or (ii) minimizing the number of hyperplanes for a given error. We assessed the performance of the proposed framework using data from two large hydropower plants of the Brazilian system. The first has 3568 MW distributed in 50 Bulb-type GUs and operates as a run-of-river hydro plant. In turn, the second, which can vary the reservoir volume by up to 1000 hm3, possesses 1140 MW distributed in three Francis-type units. The results showed a variation from 0.040% to 1.583% in terms of mean absolute error and 0.306% to 6.356% regarding the maximum absolute error even with few approximations.

Optimal management of hydropower production: Case of Memve’ele hydropower reservoir policy

Optimizing the production of electrical energy through the efficient management of reservoirs is one of the major concerns in power supply. Then, optimization methods have been employed to solve the problem of service continuity in a generation. Many reservoir management issues are indeed addressed without achieving a desired solution in line with demand. The main motivation for state-of-the-art technology is to develop robust and intelligent methods that enable strict compliance with production restrictions while meeting energy demand. This paper follows this perspective by proposing the water supply and hydroelectric production through a hybrid method combining the differential evolution and two constraints processing treatments (TCPT). The interest of the constraint method using here, including its superiority of feasible solutions (SF) and auto-adaptative penalty (AP) is its ability to overcome premature convergence and to obtain very accuracy near optimal solutions. AP technique improve by its ability process through tedious trial and error methods to select the best penalty coefficient during implementation. SF, for its part, is a technique for comparing unrealistic solutions on the basis of the violation of global constraint aimed at pushing unrealistic solutions towards the feasible region, while comparing two workable solutions on objective value improves the overall solution. To compare the performance of the proposed hybrid method of optimization with the SF and AP techniques as a constraint method, a series of experiments was firstly carried out using 25 well know benchmark functions. The obtained results as opposed to the current hybrid method such as TCPT-PSO, TCPT-ABC and TCPT-GA have exhibited the method’s superiority. Based on these performances, we employed the proposed hybrid method to manage the water supply and hydroelectric production of the Memve’ele reservoir. The application on the management of Memve’ele Reservoir demonstrates its accuracy in providing a near-optimal solution on the order of 99.7% for 1945s, 1985s and 1988s of demand during the seven hydrological years of the Ntem Valley with real mean square error (RMSE) in order of 10−7 for water supply and hundredth for hydropower reservoir operation.

The process of electrification in Darjeeling hills with special reference to Sidrapong hydropower project

The paper gives an overview of the origins and development of hydroelectricity in Darjeeling hills during colonial period and the process of electrification of the region. As the history of the city gained lots of attention from scholars due to its colonial heritage, but its legacy in the production of hydroelectric power wasn’t gained so much attention till now. Darjeeling was one those earliest cities in India, which experienced the luxury of electricity in 19th century India. Here the special focus will be shifted on the Sidrapong power plant, which is known as the earliest hydroelectricity plant in India. Even the production of hydroelectricity was started here with the Sidrapng plant, later various other production units and extensions were installed in the areas like Lebong, Karseong and Kalimpong. In this article, an attempt was made to discuss factors behind the establishment of the project, important events during its developmental stages, production capacity, management, later extensions and other related things elaborately. The paper also contains several unknown data and details and statistics about those projects.

Hydroelectric production in Akosombo, and the development of irrigated agriculture upstream, a fair balance to be found to reconcile regional energy and food security. - Challenges of the Volta Basin Water Charter

The Volta River is a West African river that flows from Burkina Faso to Ghana where it empties into the Atlantic Ocean. It basin extends over six countries: Benin, Burkina Faso, Côte d’Ivoire, Ghana, Mali and Togo. These states, members of the Volta Basin Authority, have committed themselves to drawing up a Water Charter. One of the challenges of this international agreement is to agree on a reasonable level of abstraction to reconcile food and energy security for the populations, while guaranteeing the minimum needs of the ecosystems. Supported by an appropriation of the needs-resources balance through the use of Lego® bricks, their reflection was supported by a hydro-economic analysis. This analysis consisted in comparing the added value associated with an agricultural abstraction - which leads to a definitive consumption of water upstream of the basin, for example in Bagré in Burkina Faso - and the one associated with the same quantity of water if it had been allowed to flow and turbined in one of the hydroelectric facilities located further downstream, for example in the large Akosombo dam in Ghana. The results show that the agricultural valorisation of a continuous abstraction of one m3/s, i.e. 30 Mm3 per year, allows to irrigate 1,500 ha and generates an added value of 1,300 M FCFA per year, i.e. 44 FCFA/m3. This volume of 30 Mm3, taken upstream of the dam would induce a loss of hydroelectric production of 6 GWh/year, worth 297 M FCFA, i.e. 10 FCFA/m3. The economic value of each m3 withdrawn to develop irrigated agriculture upstream of the basin is thus higher than that of each m3 turbined in the Akosombo-Kpong complex. Within the limit of an acceptable reduction of hydropower production, the economic development of the basin as a whole would thus benefit from the development of irrigated agriculture.

Effects of hydropower management on the sediment composition and metabolism of a small Alpine lake

The ecological equilibrium of water reservoirs may differ from that of natural lakes. We questioned this difference by analysing the sediments of a small oligotrophic Alpine lake, whose management was modified for hydroelectric production since 1976. Corne Lake is formed by a shallow depression connected to a deep depression. The hydropower management induced water level fluctuations (+2 m in summer; −8 m in winter) that emptied the shallow depression during the winter months and promoted the erosion of littoral soils and tributary channel sediment and the sedimentation in the deep depression. The sediment of the original lake was a low-density organic mud. The sediment composition varied according to 3 phases, which chronology is debated. During a first phase we measured an increase in the ratio of Diatom/Chrysophycea and bioavailable P, as well as a decrease in the C/N ratio and bulk radiocarbon age of the sediment, suggesting a trophic surge. A second phase was characterised by a high rate of mineral sedimentation, an increase of benthic diatom genera in the deep depression of the lake and acidophilic diatoms in the shallow depression. In the third phase covering the last upper cm of the cores, the sediment tended to return to its initial composition, but the algae community differed from its initial state. We suggest that the management of Alpine lakes as reservoirs induce long-term ecological changes in relation to water level fluctuations and littoral habitats degradation.

Environmental Flow Scenarios for a Regulated River System: Projecting Catchment‐Wide Ecosystem Benefits and Consequences for Hydroelectric Production

AbstractTo enable prioritization among measures for ecological restoration, knowing the expected benefits and consequences of implementation is imperative but rarely explicitly quantified. We developed a novel method to prioritize among environmental flow measures to rehabilitate ecosystems in the Ume River catchment in northern Sweden, a river system heavily regulated for hydropower production. Our strategy was to identify measures with minimal impact on hydropower production while providing substantial environmental benefits. Based on field surveys of remaining natural values and potential for ecological rehabilitation, we quantified the projected gain in habitat area of implementing environmental flows for target organism groups, for example, lotic fish species and riparian vegetation, along the whole river length. We quantified the consequences for hydropower production by identifying a set of hydropower operational rules reflecting the constraints added by environmental flows. We then used production optimization software to calculate changes in hydropower production and revenues. Implementing restrictions on zero‐flow events by mandating minimum discharge at all run‐of‐river hydropower stations and allocating 1%–12% of mean annual discharge to bypassed reaches in the entire catchment would result in a 2.1% loss of annual electricity production. Adding flow to fishways would increase the loss to 3.1% per year. With implementation of more natural water‐level fluctuations in run‐of‐river impoundments, the loss increases to 3.8%. These actions would increase the habitat for lotic species like the grayling Thymallus more than threefold and increase the area of riparian vegetation by about 66%. Our method forms a basis for ongoing implementation of nationwide environmental rehabilitation schemes.

Hydrological Drought Analysis for Bolu City with Streamflow Drought Index

Hydrological drought refers to the decrease in the amount of water found in surface or groundwater resources and monitoring of this natural disaster is very important due to causing serious problems in drinking and irrigation water supply and hydroelectric energy production. In this study, hydrological drought analysis was made for two streams in Bolu city located in the Western Black Sea Region in the north of Turkey and 3, 6 and 12 month streamflow drought indices were calculated by using the Streamflow Drought Index method. For this aim, the streamflow data of Bolu stream - Beşdeğirmen and Ulusu - Afatlar streamflow monitoring stations were used. According to the results, extreme and severedroughts were determined for two stream flow stations and it is seen that drought periods varied between 1 and 9 years. The most severe and longest droughts were detected for Bolu stream - Beşdeğirmen station. Mild droughts are much higher than moderate, severe and extreme droughts. It has been observed that the severity and number of drought for Bolu stream - Beşdeğirmen station have increased in recent years. In order to reduce the effects of hydrological drought, hydrological drought should be monitored continuously and necessary precautions should be taken regarding the management of water resources. People should be informed about water consumption and so waste should be prevented. Interms of irrigation water, drip irrigation method should be used instead of flood irrigation or sprinkler irrigation methods. For this aim, farmers should be made aware of this issue. Alternative renewable energy sources or other energy sources should be used for reductions in hydroelectric energy production.

The need for stewardship of lands exposed by deglaciation from climate change

AbstractAlpine glaciers worldwide will lose most of their volume by the end of the 21st century, placing alpine ecosystems and human populations at risk. The new lands that emerge from retreating glaciers provide a host of challenges for ecological and human adaptation to climate change. In these novel proglacial landscapes, ecological succession and natural hazards interplay with local agriculture, hydroelectric production, mining activities, and tourism. Research has emphasized the importance of understanding adaptation around socio‐environmental systems, but regional and global management efforts that support local initiatives and connect novel proglacial landscapes to ecological, social, and cultural conservation opportunities are rare and nascent. The characteristics of these emerging lands reflect the nexus of alpine ecosystems with socio‐political histories. Often overlooked in glacial‐influenced systems are the interdependencies, feedbacks, and tradeoffs between these biophysical systems and local populations. There is no coordinated strategy to manage and anticipate these shifting dynamics, while affirming local practices and contexts. There is an opportunity to initiate a new conversation and co‐create a governance structure around these novel landscapes and develop a new framework suitable to the Anthropocene era. This article first synthesizes the rapid socio‐environmental changes that are occurring in proglacial landscapes. Second, we consider the need for integrating “bottom‐up” with “top‐down” approaches for the sustainable management of proglacial landscapes. Finally, we propose establishing a transdisciplinary initiative with policy‐related goals to further dialogues around the governance and sustainable management of proglacial landscapes. We call for increased cooperation between actors, sectors, and regions, favoring multiscale and integrated approaches.This article is categorized under:Climate, Ecology, and Conservation > Conservation Strategies

Hydropower production prediction using artificial neural networks: an Ecuadorian application case

Hydropower is among the most efficient technologies to produce renewable electrical energy. Hydropower systems present multiple advantages since they provide sustainable and controllable energy. However, hydropower plants’ effectiveness is affected by multiple factors such as river/reservoir inflows, temperature, electricity price, among others. The mentioned factors make the prediction and recommendation of a station’s operational output a difficult challenge. Therefore, reliable and accurate energy production forecasts are vital and of great importance for capacity planning, scheduling, and power systems operation. This research aims to develop and apply artificial neural network (ANN) models to predict hydroelectric production in Ecuador’s short and medium term, considering historical data such as hydropower production and precipitations. For this purpose, two scenarios based on the prediction horizon have been considered, i.e., one-step and multi-step forecasted problems. Sixteen ANN structures based on multilayer perceptron (MLP), long short-term memory (LSTM), and sequence-to-sequence (seq2seq) LSTM were designed. More than 3000 models were configured, trained, and validated using a grid search algorithm based on hyperparameters. The results show that the MLP univariate and differentiated model of one-step scenario outperforms the other architectures analyzed in both scenarios. The obtained model can be an important tool for energy planning and decision-making for sustainable hydropower production.

Structural health monitoring of concrete gravity dams

The ageing of dams is one of the major challenges in specifically Slovenian and generally global dam engineering. Dams are exposed to environmental (climate) changes, as well as time-dependent effects, such as changes in the operating schedules of dams intended primarily for hydroelectric production. These changes can accelerate dams’ ageing and lead to a decrease in their structural and operational safety. Dams are an important part of the infrastructure, as they bring about numerous benefits and at the same time they are also sources of risk. For example, in the event of partial or total failure they pose significant risk to downstream areas. Aging of dams, preserving their functionality, and maintaining their structural health are currently the main challenges of dam engineering. The mean age of Slovenian dams is already over 40 years, although Slovenia is not unique in this situation. In this paper there is presented a novel methodology to monitor structural health of concrete dams, with the use of noncontact and contact measurements through observation of structural vibrations. We present the in-situ experiment on the Brežice dam that began during the dam’s construction and continued into the first year of its operation.

Resilience of hydropower plants to flow variation through the concept of flow elasticity of power: Theoretical development

Fluctuation in hydro-electricity production is primarily attributed to natural and human-induced flow variations. Reduced electricity generation because of unavailability of flow inflicts significant upward pressure on the sources and prices. Despite studies on the impact of externalities on river flow variation, there is a distinct research gap on the responsiveness of hydropower plants to change in flow. This study has introduced a novel concept of flow elasticity of power (ε) to assess the resilience of hydropower projects to flow variation. The theoretical aspect has been established for run-of-river (ROR) and storage-type (ST) cases separately and validated at two projects, one of each type, located in the Budhigandaki Basin in central Nepal. Responsiveness of hydro-projects to the topographical parameters are also dealt with here. For ROR systems, wide-ranging values of ε indicate varying levels of resilience to power generation and loss of resources. For ST projects, the response differs according to emptying, filling and ROR-equivalent phases. Furthermore, strong topographical implications on power production and its elasticity are evident. This concept of ε sets out a significant research contribution in the hydropower sector and demonstrates its possibility of direct application in projects ‘inpriori’ as well as ‘posteriori’ while planning/designing and operating/updating stages, respectively. The ε coefficient scientifically informs the planners and developers on the sensitivity of the powerplants to hydrological variations and topography ultimately benefitting the existing global challenge to minimize the loss of precious resources for sustainable hydropower development.