3,018 results
Search Results
2. Measuring Non-Market Values for Hydropower Production and Water Storage on the Colorado River: A White Paper Investigation
- Author
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Janie Chermak, Thomas Stephen Lowry, David Brookshire, Calvin Shaneyfelt, and Peter Holmes Kobos
- Subjects
White paper ,business.industry ,Water storage ,Environmental engineering ,Environmental science ,Production (economics) ,business ,Hydropower - Published
- 2017
3. Review of water and climate adaptation financing and institutional frameworks in South Asia. Background Paper 3
- Author
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Diana Suhardiman, Alan Nicol, Indika Arulingam, Sashan Rodrigo, and Sanjiv de Silva
- Subjects
Food security ,Poverty ,International waters ,business.industry ,Political science ,Regional science ,Population growth ,Water supply ,business ,Risk management ,Hydropower ,Water scarcity - Published
- 2019
4. The on-paper hydropower boom: A case study of corruption in the hydropower sector in Bosnia and Herzegovina
- Author
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Jonas Østergaard Nielsen and Özge Can Dogmus
- Subjects
Sustainable development ,Economics and Econometrics ,010504 meteorology & atmospheric sciences ,business.industry ,Corruption ,Economic policy ,media_common.quotation_subject ,Developing country ,010501 environmental sciences ,01 natural sciences ,Boom ,Sustainability ,Business ,Empirical evidence ,Nexus (standard) ,Hydropower ,0105 earth and related environmental sciences ,General Environmental Science ,media_common - Abstract
The demand for hydropower production, as a prominent sustainable development strategy, has created a boom in the number of planned hydropower projects, especially small ones. These projects are mainly located in post-socialist transition and developing countries. However, emerging evidence suggests that most of the projects remain on paper. One reason for this is prevalent corruption. In the literature, corruption has been identified in megaprojects but a significant number of hydropower projects are smaller in size. This leaves a literature gap and a subsequent lack of understanding regarding corruption and its potential connection to the absence of hydropower construction. We argue that it also creates a ‘safe space’ for corrupt actors who use the sector for personal gain. In this paper, we address this nexus of unfinished hydropower projects, sustainable development in transition countries, corruption, and lack of scholarly attention by presenting empirical evidence from Bosnia and Herzegovina. We highlight that sustainability goals associated with hydropower might be distorted, especially in transition countries as they are intermingled with hydropower projects that are embedded in complex bureaucratic structures. We conclude that focusing on the sector might improve its management, thus contributing to sustainable development, and also help to decrease the corruption risk.
- Published
- 2020
5. Hydro Power Technology in India:A Review Paper
- Author
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Abhishek Kumar and Dil muhammed Akbar Hussain
- Subjects
Engineering ,business.industry ,Financial aspects ,Hydro Development ,Comparison ,Civil engineering ,Indian Strength in Hydro Engineering ,Economic Analysis ,Modeling and simulation ,Hydro power ,Modeling and Simulation ,Economic analysis ,business ,Policies ,Hydropower - Abstract
Encouraged by a maintained monetary process and ascend in economic advantage levels, Asian nation is ready to confront an essential increment in vitality request inside the following couple of decades that conjointly translates into higher interest for power. The hole inside the power request supply situation is featured by the everyday reality that the nation old a pinnacle deficiency of 5.2% and a vitality shortfall of 4.2% in FY 13-141, with the abundance western unfit to offer reparations for the extremely shortage northern, southern and north-eastern areas. Considering partner vitality snap of 0.82, Asian nation is anticipated to need around seven-membered yearly development in power offered to manage an esteem development of around 8.5% p.a. over after a couple of years. This requires stable every potential source to deal with the shortage and take care of the demand development for quick monetary improvement though thinking about worries of long-run property, ecological and social perspectives. Global environmental change and distinctive negative impacts of exploitation of petroleum products for control age together with developing contemplations over vitality security are driving the augmentation of hydropower around the globe. Even though supply based for the most part hydropower returns have come underneath feedback on account of ozone-harming substance and alkane arrangement discharges on the far side good breaking points, most hydro-rich nations have taken after partner coordinated full life-cycle approach for the appraisal of the preferences and effects to ensure property. The examination is a preliminary to bring out strikingly the past, blessing, and way forward for hydro vitality in India; some significant parts of the overall circumstance are specified. Meaningful strategies of the local government are contacted upon ace re data while talking about the bottlenecks experienced in rapid hydropower division advancement.
- Published
- 2018
6. Energy-Water Nexus in Southern Africa : Background Paper to Support Dialogue in the Region
- Author
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World Bank
- Subjects
hydropower ,regional integration ,water resources management ,climate change ,hydrology ,electricity - Abstract
The objective of this paper is to provide high-level background information on the interdependency between the supply of electricity and water in Southern Africa. The paper assimilates information based an extensive review of recent work on the energy and watersectors in the region and beyond, and the World Bank’s sector dialogue in the region. The paper is intended to help facilitate a dialogue on the energy-water nexus in the region, especially fromthe perspective of electricity sector planning, and help the World Bank engage key sectorstakeholders on the issue.The value of this paper is in bringing together the latest knowledge work and other key information relevant for energy-water nexus dialogue in Southern Africa. This information has been derived from a number of fragmented sources, and an effort has been made to present the information in a logical framework, in one document that can help initiate discussions in the region.This paper was conceptualized as a background discussion paper and does not seek to make any recommendations on policy alternatives to tackle challenges facing the region on energy-water nexus issues. Any recommendations should be rooted in a thorough assessment of the specificchallenges, institutions and objectives of the region; and most importantly should follow from aconstructive regional dialogue amongst key stakeholders.The issues and implications that surround the energy-water nexus are numerous. The use of electricity and water as critical inputs to economic activity, implies that there are many interlinkages that can be explored. To increase the usefulness of the information and the framework presented, this paper focuses on the perspective of electricity supply, and highlights nexus issues that are directly relevant to it. Important related nexus issues such as agriculture and its dependence on reliable water and electricity (the energy-water-food nexus) are not considered and are left for future work. Thus, in referring to the energy–water nexus, the paper considers issues on electricity and water sectors in relation to electricity supply and long-term planning around it, including the feedback loop to water. By highlighting key analytical work and drawing insights relevant to Southern Africa, this paper aims to support an informed regional dialogue on decision making about the energy–water nexus in the region.
- Published
- 2016
7. Habitat banking in Swedish rivers and water bodies: A concept paper on implementing the EU Water Framework Directive
- Author
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Stage, Jesper
- Subjects
hydropower ,Sweden ,Water Framework Directive ,habitat banking ,Economics ,Ekonomi - Nationalekonomi ,Nationalekonomi ,Business / Economics - Economics - Abstract
The European Union (EU) Water Framework Directive entails extensive environmental improvement goals for lakes and rivers throughout the Union. Realising these goals in countries such as Sweden, which has tens of thousands of water bodies, many of which are used for commercial activities such as hydropower, presents a considerable challenge for policy. In this paper, habitat banking – where environmental improvements in one location are used to offset measures that reduce environmental quality elsewhere – is discussed as a potential way forward. The conclusion is that although this would likely be limited to banking within individual river systems rather than across the entire country, it would nonetheless be an interesting option to consider. Although habitat banking is more complex in aquatic than in terrestrial systems, because of the migratory nature of many of the keystone species improvements in the downstream parts of a river system can potentially generate enough environmental benefits to offset the impacts of measures further upstream. Godkänd; 2013; 20160304 (jessta) Vatten som ekonomisk resurs, Framtagande av relevant och användaranpassad samhällsekonomisk modell för miljöåtgärder för kraft och liv i vatten (FRAM-KLIV)
- Published
- 2013
8. EPRI-DOE Conference on Environmentally-Enhanced Hydropower Turbines: Technical Papers
- Author
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T. Hogan
- Subjects
Engineering ,business.industry ,Environmental engineering ,business ,Construction engineering ,Hydropower - Published
- 2011
9. Diversion of Excess Water in Badulu Oya for Augmentation of Loggal Oya Reservoir for Generation of Hydropower (Concept Paper)
- Author
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A. K. D. N. Atukorala
- Subjects
Hydrology ,Dry zone ,Excess water ,business.industry ,Water source ,Environmental science ,Economic shortage ,STREAMS ,Water resource management ,business ,Hydropower - Abstract
With the implementation of Uma Oya Multipurpose Diversion Project, part of Uma Oya water will be diverted to the Kirindi Oya basin to compensate for the water shortages in the south-east dry zone. As a result the water received presently at Rantambe from Uma Oya will be reduced approximately by one third. Badulu Oya which joins the Malaweli Ganga downstream of Uma Oya flows underneath the Minipe Right Bank (RB) canal. Hence major part of the water in Badulu Oya at present flows to Mahawel Ganga without being made use. Further, there is certain potential energy in the water of Badulu Oya and adjacent Loggal Oya which can be converted to electrical energy by augmenting the water source of Minipe RB canal. The objective of this article is to identify the most probable means to investigate the possibilities of harnessing both water resource and hydropower potential in the two streams.
- Published
- 2012
10. Design of an Autonomous IoT Node Powered by a Perovskite-Based Wave Energy Converter.
- Author
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Drzewiecki, Marcin and Guziński, Jarosław
- Subjects
WAVE energy ,PIEZOELECTRIC ceramics ,OCEAN wave power ,INTERNET of things ,OCEAN waves ,PEROVSKITE ,LEAD zirconate titanate - Abstract
This paper presents the results of experimental research focused on wave energy harvesting and its conversion to power Internet of Things (IoT) devices. The harvesting and conversion process was performed using a wave energy converter (WEC) consisting of a lead zirconate titanate piezoelectric ceramic perovskite material and a prototype power electronic circuit. The designed WEC was considered as a power supply for an end node device (END) of an IoT network. The END consisted of a long-range radio module and an electronic paper display. A set of physical experiments were carried out, and the results confirmed that an energy surplus was supplied by WEC compared to the energy consumed by the END. Hence, the proposed scheme was experimentally validated as a convenient solution that could enable the autonomous operation of an IoT device. The use case presented here for the proposed WEC was analysed for selected sea areas on the basis of wave statistics. The novelty of this paper arises from an investigation that confirms that WECs can significantly contribute to the development of wireless and mobile IoT communication powered by freely available sea wave energy. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
11. Research on Key Technologies of Solar Photovoltaic Building Integration
- Author
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Jianfeng Zhang, Yan Li, and Yinghao Gan
- Subjects
Nameplate capacity ,Engineering ,Architectural engineering ,Energy development ,White paper ,Wind power ,Electricity generation ,business.industry ,Photovoltaic system ,business ,China ,Hydropower - Abstract
On December 21, 2020, The State Council Information Office issued a white paper titled “China’s Energy Development in the New Era,” in which the installed capacity of hydropower, wind power, photovoltaic power and biomass power generation in China ranked first in the world [1]. Solar photovoltaic power generation is the most important development direction of clean energy in the world. It is an important energy strategy to combine it with the field of construction in China. This paper mainly introduces the characteristics and problems of the key technologies of solar photovoltaic building integration, and explores its future development direction and ways, in order to constantly promote the industrialization of new energy technology in China.
- Published
- 2021
12. Practicing security: securitisation of transboundary rivers by hydrocrats in Himalayan South Asia.
- Author
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Vasani, Harsh
- Subjects
EXPERTISE ,GEOPOLITICS ,CIVIL service - Abstract
This paper examines the intersection of regional geopolitics and the governance of transboundary rivers using the case studies of multipurpose reservoirs in Himalayan South Asia. It uncovers the various ways Indian hydrocracy uses its institutional and technical expertise to strengthen India's centrality in Nepal's water and hydropower sectors. The practices of security undertaken by the hydrocrats are classified as structural, institutional, and statutory acts. By focusing on practices of an epistemic community like hydrocrats, this paper addresses longstanding weaknesses of the securitisation theory of being elitist and ignoring the agency of mid-level bureaucrats. It also highlights the constructivist nature of international politics. The findings contribute empirically to securitisation theory's 'Paris School' of thought. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
13. Isang Paunang Pagsasakasaysayan ng Caliraya Dam sa Silangang Laguna, 1939-1947.
- Author
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AGUSTERO ASUNCION, RUBEN JEFFREY
- Subjects
LANDFORMS ,HISTORICAL source material ,DAM design & construction ,BODIES of water ,ELECTRIC power production - Abstract
Copyright of Daluyan: Journal ng Wikang Filipino is the property of University of the Philippines - Diliman and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2023
14. Implications to the electricity system of Paraguay of different demand scenarios and export prices to Brazil
- Author
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Mark Howells, Carlos Centurion, Eunice Ramos, Thomas Alfstad, Eduardo Ortigoza, Ioannis Pappis, Pedro E. Gardel-Sotomayor, and Silvia Ulloa
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Technology ,Economics and Econometrics ,BARGAINING POWER ,Latin Americans ,Energy & Fuels ,Power station ,Natural resource economics ,020209 energy ,HYDROPOWER ,Investment outlook ,02 engineering and technology ,Demand scenarios ,010501 environmental sciences ,OSEMOSYS SAMBA ,01 natural sciences ,Energy planning ,Cost-optimization ,0202 electrical engineering, electronic engineering, information engineering ,Per capita ,Project finance ,SUPPLY SECTOR ,Hydropower ,0105 earth and related environmental sciences ,BOTTOM-UP ,Consumption (economics) ,Original Paper ,Science & Technology ,business.industry ,Investment (macroeconomics) ,MODEL BASE ,0906 Electrical and Electronic Engineering ,General Energy ,Electricity generation ,Modeling and Simulation ,ENERGY-POLICY ,Electricity ,business ,OSeMOSYS ,INTEGRATION - Abstract
Paraguay's power system is based entirely on hydropower. It serves as the largest net electricity exporter in Latin America. Nonetheless, the country´s electricity consumption per capita is one of the lowest in the world and the transmission and distribution network has one of the highest losses in Latin America. This paper presents an electricity expansion investment outlook (2018–2040) for Paraguay using OSeMOSYS, analyzing three electricity demand scenarios under different electricity export prices to Brazil. The study identifies the least-cost power generation mix, future investments and the financial requirements to meet the needs of different demand scenarios. We find that Paraguay will need to invest in hydropower plants, by mainly expanding the capacity of Yacyreta to cover its electricity needs and sustain national electricity exports levels. In the High demand scenario, where the electricity demand could approximately double by 2040, the country's overall electricity exports decrease by 50% compared to the Reference scenario. Based on the different scenarios examined, the government spends approximately 18.3–31.2 billion USD on power plant investments for the period 2018–2040 to cover future electricity demand. The findings could be useful in supporting decision-making concerning socio-economic development pathways in the country. Supplementary Information The online version contains supplementary material available at 10.1007/s12667-020-00420-w.
- Published
- 2021
15. Research on hydro-photovoltaic complementary analysis of Yangfanggou hydropower station on Yalong River.
- Author
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Bin He, Weixuan Yin, Guohua Liang, and Lei Jiang
- Subjects
WATER power ,PHOTOVOLTAIC power generation ,CLEAN energy ,WATER supply ,CONSTRUCTION planning ,ELECTRIC fields - Abstract
Hydropower and photovoltaic power are widely used as clean energy sources around the world. Hydro-Photovoltaic complementary is precisely the use of the regulation performance of hydropower stations and the peak regulation performance of PV electric fields to improve the system's power generation efficiency. The Yalong River basin as one of China's clean energy bases, is rich in water and light resources. And now its midstream Yangfanggou hydropower station has just been completed, and the relevant PV electric field is in the construction planning stage. It is worth studying how to effectively utilize its hydropower and PV output resources. Therefore, Yangfanggou hydropower station and its PV electric field are taken as the research objects in this paper. The possibility of hydro-photovoltaic complementarity is analyzed within the year and day respectively. Then, a short-term scheduling model of hydrophotovoltaic complementarity is constructed according to the principle, and its operation mode and effect are optimized using the genetic algorithm NSGA-II. The results indicate that the annual power generation of the system is increased by about 1.4 billion kWh from the original hydropower through the hydrophotovoltaic complementary, and the annual guaranteed output is also increased with a large increase degree at the same time. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
16. Stable operating limits and improvement methods for hydropower and photovoltaic integration through MMC-HVDC systems.
- Author
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Maolan Peng, Lei Feng, Shuwen Zhang, and Wei Zhao
- Subjects
WATER power ,RENEWABLE energy sources ,ELECTRICAL load shedding ,HIGH voltages ,FACTOR analysis - Abstract
This paper addresses the critical need to determine the stable operating limit of modular multilevel converter-based high voltage direct current (MMC-HVDC) systems, particularly concerning the integration of extensive renewable energy sources. To achieve this, the steady-state mathematical model and state-space model of bundled hydropower and photovoltaic integration through MMCHVDC systems are established. A novel methodology considering steady-state and small-signal stability constraints is proposed to compute the stable operating region of the system. The quantitative assessment reveals that diminishing AC system short-circuit capacities amplify restrictions from small-signal stability constraints, thereby reducing the system's stable operating region. Eigenvalue and participation factor analyses shed light on the pivotal factors affecting smallsignal stability in weak AC systems. To expand the system's stable operating region, a supplementary frequency damping control strategy is proposed. The theoretical analysis and calculation results are validated by building a simulation model for the bundled hydropower and photovoltaic integration through MMCHVDC systems in PSCAD/EMTDC. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
17. Design and Evaluation of the Compact and Autonomous Energy Subsystem of a Wave Energy Converter.
- Author
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Drzewiecki, Marcin and Guziński, Jarosław
- Subjects
WAVE energy ,OCEAN waves ,ENERGY development ,RENEWABLE energy sources ,ENERGY conversion ,MICROGRIDS ,ENERGY harvesting ,WIRELESS communications - Abstract
This paper presents the results of the design process focused on the development of the energy subsystem (ES) of a wave energy converter (WEC). The ES is an important electrical part that significantly affects the energy reliability and energy efficiency of the entire WEC device. The designed ES was intended for compact WECs powering IoT network devices working in the distributed grid. The developed ES is an electronic circuit consisting of three cooperating subsystems used for energy conversion, energy storage, and energy management. The energy conversion subsystem was implemented as a set of single-phase bridge rectifiers. The energy storage subsystem was a battery-less implementation based on the capacitors. The energy management subsystem was implemented as a supervisory circuit and boost converter assembly. The designed ES was verified using the physical experiment method. The model experiment reflected the operation of the designed ES with a piezoelectric PZT-based WEC. The experimental results showed a 41.5% surplus of the energy supplied by ES over the energy demanded by the considered load at a duty cycle of ca. 6 min—37.2 mJ over 26.3 mJ, respectively. The obtained results have been evaluated and discussed. The results confirmed the designed ES as a convenient solution, which makes a significant contribution to the compact WECs that can be applied among others to a distributed grid of autonomous IoT network devices powered by free and renewable energy of sea waves. Finally, it will also enable sustainable development of mobile and wireless communication in those maritime areas where other forms of renewable energy may not be available. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
18. The electricity supply industry in the Democratic Republic of the Congo
- Author
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Ernst Uken and JM Lukamba-Muhiya
- Subjects
lcsh:GE1-350 ,Economic growth ,Mains electricity ,General Computer Science ,business.industry ,Natural resource economics ,electricity use ,Democratic Republic of Congo (DRC) ,hydropower ,Public–private partnership ,General Energy ,White paper ,Electrification ,lcsh:Energy conservation ,Economics ,Electricity ,lcsh:TJ163.26-163.5 ,business ,Electricity retailing ,Monopoly ,public private partnership ,Hydropower ,lcsh:Environmental sciences - Abstract
The electricity supply industry of the Democratic Republic of Congo is reviewed, from the formation of the Societé National d’Electricité (SNEL) in 1970 until today. The DRC government established a national utility, because electricity is a key element in the socio -economic development of a country. Due to the national monopoly of SNEL, hydropower plants could be constructed such as Inga1 and Inga2. They supply power to mining in the Katanga province, and to a steel company in Maluku, not far from Kinshasa. Currently, Inga1 and Inga 2 are not operating at full capacity. Many hydropower and thermal plants are located in different provinces and need to be refurbished to increase their capacity of electricity for the DRC. Due to technical problems, SNEL only generates 1150 MW. The electrification programme in urban and rural areas across the DRC caters for less than 10% of the 60 million inhabitants. In 1980, the government implemented a policy called Plan Directeur de SNEL for electrification, but the policies never reached their objectives. No Energy White Paper exists which outlines the entire policy framework for energy supply and demand. Power sector reform has also not been implemented in the electricity sector. This paper outlines future government options in the electricity sector. Accordingly, the Public Private Partnership model could play a major role in attracting private partners to invest in the electricity sector in order to have different hydropower and thermal plants refurbished.
- Published
- 2017
19. Species diversity of fishes in the Dingqu River Basin, tributary of the upper Yangtze River, China
- Author
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Baoxiang Liu, Jie Bai, Huiqin Li, Yingchun Xing, and Yahui Zhao
- Subjects
Asia ,QH301-705.5 ,Qinghai-Tibet Plateau ,Biodiversity & Conservation ,Endangered species ,Drainage basin ,Biodiversity ,Tributary ,distribution ,Animalia ,Biology (General) ,Endemism ,Ecology, Evolution, Behavior and Systematics ,geography ,geography.geographical_feature_category ,Plateau ,Ecology ,Cenozoic ,Species diversity ,endangered species ,Data Paper (Biosciences) ,habitat condition ,hydropower ,Fishery ,Habitat ,endemism - Abstract
The Dingqu River Basin, a major tributary of the upper Yangtze River, is located at southeast edge of the Qinghai-Tibet Plateau of China. The fishes of this plateau constitute a major faunal component of this basin, particularly Schizothoracinae (Cypriniformes: Cyprinidae) and Triplophysa (Cypriniformes: Nemacheilidae). Hydropower development is an impact that affects natural habitats and biological resources of the upper Yangtze River and this has led to a decrease in biodiversity. This study investigated the species diversity of fishes of the Dingqu River Basin and accumulated basic data for conservation of biodiversity and assessment of ecological health of the upper Yangtze River. The upper streams of the Jinshajiang River harbours numerous endemic fish species in China. Most of them belong to the Qianghai-Tibet Plateau fish fauna. However, while the fish species of the Jinshajiang River have been well studied, there is still a gap in the research on fish species diversity of the Dingqu River Basin tributary. This study provides information for 18 native fish species belonging to two orders, four families, three subfamilies and eight genera, and is the first complete record of fishes in the Dingqu River Basin, a primary tributary of the Yangtze River. Supplemental information of species diversity in the Jinshajiang River is also provided. The study includes two datasets, which present taxonomic, distribution, habitat condition, endemism and threat information for each species collected from the Dingqu River Basin and historical literature, respectively. In particular, these fish species all have limited distribution within the south-eastern Qinghai-Tibet Plateau areas of China and could determine the importance of habitat protection for the upper Yangtze River.
- Published
- 2021
20. The Quest for Resilient Sustainable Development and Low-Carbon Energy Transitions: Investigating the Challenges and Success Factors for Mini-Grids in Malawi.
- Author
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Mwale, Vincent, Blanchard, Richard, Ngonda, Tiyamike, Nkhoma, Richard, Ogunna, Chukwudi, and To, Long Seng
- Abstract
Renewable energy mini-grids are considered a cost-effective way to provide electricity for a large proportion of the population in developing countries who do not have access to it. Compared with standalone home systems and national grid systems, mini-grids can potentially offer a better service. They can be deployed faster, making them essential for sustainable development, especially in rural and semi-urban areas of developing countries. However, mini-grids often face challenges regarding their resilience, and many fail to survive beyond their pilot phases. This paper aims to identify the factors contributing to the success of mini-grids and to identify common themes that can help existing and future mini-grid developments become more resilient and influence policy decision making. To achieve this goal, we developed a database of the status of mini-grids in Malawi, with the energy generation resource(s) of their installed capacity, enabling factors, and challenges. We undertook a more detailed investigation of two hydro mini-grid systems—Bondo and Chipopoma. We collected qualitative and quantitative data through literature reviews, site visits, interviews, and observations. The study identified 19 mini-grids with a combined installed capacity of 26 MW. Of these, seven had been abandoned, and one was under development. Several factors that affect successful mini-grid efficacy in Malawi were identified, including financial resourcefulness, technical resourcefulness, policies and regulations, community engagement and capacity building, cross-sector linkages, and institutional organisational frameworks. These factors need to be integrated into decision making by all stakeholders to ensure the enhancement of resilience and the sustainable development of mini-grids. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
21. Assessing the Impacts of Changing Connectivity of Hydropower Dams on the Distribution of Fish Species in the 3S Rivers, a Tributary of the Lower Mekong.
- Author
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Meynell, Peter-John, Metzger, Marc J., and Stuart, Neil
- Subjects
GEOGRAPHICAL distribution of fishes ,SPECIES distribution ,DAMS ,NUMBERS of species ,WATER power ,FISH conservation - Abstract
Hydropower plants (HPPs) create barriers across rivers and fragment aquatic ecosystems, river reaches and habitats. The reservoirs they create slow the flowing water and convert the riverine into lacustrine ecosystems. The barriers created by HPPs interrupt the seasonal migrations of many fish species, while the reservoirs drive away fish species that are dependent on flowing water habitats. This paper assesses the distribution of fish species in the 3S rivers—Sekong, Sesan and Sre Pok, in Cambodia, Laos and Viet Nam—using IUCN Red List-assessed species distribution by HydroBasin Level 8 from the freshwater reports of the Integrated Biodiversity Assessment Tool (IBAT) and their connectivity with the Mekong. There are currently 61 commissioned dams in the 3S basins and a further 2 under construction, 23 of which are larger than the 30 MW installed capacity. A further 24 HPPs are proposed or planned in these basins. The changes in connectivity caused by the dams are measured by adapting the River Class Connectivity Index (RCI
CLASS ); the original connectivity of the 3S basin taking into account the two major waterfalls in the Sesan and Sre Pok rivers was estimated at 80.9%. With existing dams, the connectivity has been reduced to 23.5%, and with all planned dams, it is reduced further to 10.9%. The resulting re-distribution of fish species occurring throughout the 3S basins is explored, by focusing on migratory guilds and threatened and endemic fish species. With all dams built, it is predicted that the total numbers of species in HydroBasins above the dams will be reduced by 40–50%. The Threatened Species Index is estimated to fall from over 30 near the confluence of the three rivers to less than 10 above the lowest dams on the 3S rivers. The analysis demonstrates how widely available global and regional datasets can be used to assess the impacts of dams on fish biodiversity in this region. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
22. Intelligent Low-Consumption Optimization Strategies: Economic Operation of Hydropower Stations Based on Improved LSTM and Random Forest Machine Learning Algorithm.
- Author
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Pan, Hong, Yang, Jie, Yu, Yang, Zheng, Yuan, Zheng, Xiaonan, and Hang, Chenyang
- Subjects
MACHINE learning ,RANDOM forest algorithms ,WATER consumption ,WATER power ,PARTICLE swarm optimization ,WATER efficiency ,RENEWABLE energy sources - Abstract
The economic operation of hydropower stations has the potential to increase water use efficiency. However, there are some challenges, such as the fixed and unchangeable flow characteristic curve of the hydraulic turbines, and the large number of variables in optimal load distribution, which limit the progress of research. In this paper, we propose a new optimal method of the economic operation of hydropower stations based on improved Long Short-Term Memory neural network (I-LSTM) and Random Forest (RF) algorithm. Firstly, in order to accurately estimate the water consumption, the LSTM model's hyperparameters are optimized using improved particle swarm optimization, and the I-LSTM method is proposed to fit the flow characteristic curve of the hydraulic turbines. Secondly, the Random Forest machine learning algorithm is introduced to establish a load-distribution model with its powerful feature extraction and learning ability. To improve the accuracy of the load-distribution model, we use the K-means algorithm to cluster the historical data and optimize the parameters of the Random Forest model. A Hydropower Station in China is selected for a case study. It is shown that (1) the I-LSTM method fits the operating characteristics under various working conditions and actual operating characteristics of hydraulic turbines, ensuring that they are closest to the actual operating state; (2) the I-LSTM method is compared with Support Vector Machine (SVM), Extreme Learning Machine (ELM) and Long Short-Term Memory neural network (LSTM). The prediction results of SVM have a large error, but compared with ELM and LSTM, MSE is reduced by about 46% and 38% respectively. MAE is reduced by about 25% and 21%, respectively. RMSE is reduced by about 27% and 24%, respectively; (3) the RF algorithm performs better than the traditional dynamic programming algorithm in load distribution. With the passage of time and the increase in training samples, the prediction accuracy of the Random Forest model has steadily improved, which helps to achieve optimal operation of the units, reducing their average total water consumption by 1.24%. This study provides strong support for the application of intelligent low-consumption optimization strategies in hydropower fields, which can bring higher economic benefits and resource savings to renewable energy production. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
23. Exploring the Macroeconomic Effects of Renewable Energy in Tajikistan: An Empirical Analysis.
- Author
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Sultonov, Mirzosaid, Hasanov, Behruz, Valizoda, Pirumsho, and Inagaki, Fumiaki
- Subjects
RENEWABLE energy sources ,COINTEGRATION ,GROSS domestic product ,ACADEMIC discourse ,ELECTRIC power consumption ,CAPITAL investments ,SUSTAINABLE development - Abstract
Tajikistan holds the eighth position globally in terms of hydropower potential, estimated at 527 terawatt-hours (TWh), with a technically exploitable capacity of 317 TWh. Only 4–6 percent of this immense potential is currently utilized. In this paper, employing a combination of the Johansen cointegration test, vector autoregression, and the Granger-causality test on annual data from 1993 to 2021, we examine the causality relationship between electricity production and key macroeconomic variables, including gross domestic product (GDP), GDP per capita, exports, imports, final consumption, capital investment, and employment, in Tajikistan. The empirical findings reveal a positive unidirectional causality from electricity production to exports and imports. A positive bidirectional or feedback causality is found between electricity production and variables such as GDP, GDP per capita, final consumption, and employment. No causality relationship between electricity production and variables such as trade openness and capital investment is observed. The exploration of complex causal relationships between electricity production and key macroeconomic variables in Tajikistan, as revealed in this study, offers a modest yet meaningful addition to academic discourse. It presents insights that may inform policymakers and stakeholders, albeit with a recognition of the limitations inherent in the findings. These insights could potentially guide the formulation of sustainable development strategies and shed light on the underutilized potential of the country's hydropower resources. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
24. Hydropower computerized reconnaissance package version 2. 0. [HYDRO-CAL, PAPER-ECON, and HYDRO-ECON]
- Author
-
C.R. Broadus
- Subjects
Engineering ,business.industry ,Hydroelectricity ,Hydro energy ,Economic analysis ,Sample (statistics) ,business ,Engineering program ,Turbine ,Simulation ,Manufacturing engineering ,Hydropower - Abstract
The Hydropower Computerized Reconnaissance (HCR) Package is a computerized preliminary engineering and economic study package for small hydroelectric projects which consists of three programs developed at the Idaho National Engineering Laboratory. One engineering program evaluates the flow characteristics of a site and determines the energy generated for various turbine configurations and two economic programs provide two levels of economic studies depending upon the amount of site-specific information available. An Apple II computer is utilized to provide a quick-turnaround capability. The models and methods used in the HCR package are described, and information is provided on program application, sample run sessions, program outputs, and listings of the main programs.
- Published
- 1981
25. Value–Risk Calculator for Blended Finance: A Systems Perspective of the Nachtigal Hydropower Project.
- Author
-
Swanson, A. Richard and Sakhrani, Vivek
- Abstract
Hydropower as a renewable source can help many countries achieve their sustainable energy and climate goals, but large projects are challenging to finance because of their costs and risks. To fully realize the climate benefits of such projects, sponsors have recently fashioned complex financing arrangements that structure and allocate risks to reduce financing costs. This paper focuses on the blended financing approach adopted for the Nachtigal Hydropower Plant (NHP) in Cameroon. The purpose of the paper is to present a detailed systems analysis of Nachtigal's financial arrangement to address the question of why the complex financing approach worked in practice. We accomplish this by creating a "financial simulator"—a computational model for evaluating risks and incentives embedded within the financing structure under different contract architectures and risk–event scenarios. Our simulator is a dynamic value–risk calculator that can be easily updated to study other climate-oriented projects that involve complex financial arrangements. We evaluated three aspects of the financing/contractual arrangements that made Nachtigal "bankable:" (i) guarantees that covered nonpayments, (ii) financial options on locally sourced loans; and (iii) an interest rate swap. We found: (i) the guarantees recovered project value threatened by four specific risks often associated with large hydropower investments (cost overruns, schedule delays, offtake risk, and low flow due to climate change); (ii) the mechanism significantly lowered interest rate charges; and (iii) private finance was mobilized—especially due to the options. The financial safeguards employed increased the likelihood of capturing the long-run sustainability benefits from NHP. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
26. Hydropower & HDI Nexus in Nordic Countries Using VAR Techniques.
- Author
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Metwally, Abdelmoneim B. M., Nabil, Shahd M., and Yasser, Mai M.
- Subjects
HYDROELECTRIC power plants ,WATER power ,IMPULSE response ,GRANGER causality test ,ENERGY consumption ,HUMAN Development Index ,LABOR mobility - Abstract
Although the movement of people from rural to urban areas has caused the increased use of energy, the abundance of water resources can be made into a form of renewable energy known as hydroelectricity. As European countries are ranked as the first users and exporters of hydropower, the production of renewable energy in developed countries such as the Nordic region has caused great impacts on economic growth and human development. The importance of this paper is to investigate the relationship between hydroelectricity and the Human Development Index by depending on some variables such as urbanization, rule of law, corruption, trade openness, and GDP per capita from 2002 to 2021 in Nordic countries. The results were estimated depending on impulse response function after conducting the Vector autoregressive model (VAR) model and Granger causality test. Results showed a negative impact from hydro plants in the short run but a significant positive impact in the long run in Nordic countries. The long-term sustainment of Human Development Index (HDI) is due to policies limiting the immigration of labor as well as protection of energy use. Water batteries are gaining popularity across Europe and their implementation is near mandatory. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
27. Representing Hourly Energy Prices in a Large-Scale Monthly Water System Model.
- Author
-
Dogan, Mustafa Sahin, White, Ellie, Yao, Yiqing, and Lund, Jay R.
- Subjects
ENERGY industries ,WATER supply ,MUNICIPAL water supply ,ENERGY consumption ,FLOOD control ,CHILLED water systems - Abstract
Water system management models represent different purposes, such as water supply, flood control, recreation, and hydropower. When building large-scale system models to represent these diverse objectives, their most appropriate time steps for each purpose often do not coincide. A monthly time step is usually sufficient for water supply modeling, but it can be too coarse for flood control, hydropower, and energy operations, where hourly time steps are preferred. Large-scale water management and planning models mostly employ monthly time steps, but using monthly average energy prices underestimates hydropower revenue and overestimates pumping energy cost because these plants tend to operate during times with above- or below-average energy prices within any month. The approach developed here uses hourly varying prices depending on the percent of monthly operating hours. This paper examines an approach that approximately incorporates hourly energy price variations for hydropower and pumping into large-scale monthly time-step water system model operations without affecting water delivery results. Results from including hourly varying energy prices in a large-scale monthly water supply model of California (CALVIN) are presented. CALVIN is a hydroeconomic linear programming optimization model that allocates water to agricultural and urban users with an objective to minimize total scarcity costs, operating costs, and hydropower revenue loss. Thirteen hydropower plants are modeled with hourly varying prices, and their revenue increased by 25 to 58% compared to revenue calculated with monthly average constant energy prices. Hydropower revenue improvements are greater in critically dry years. For pumping plants modeled with hourly varying prices, the energy use cost decreased by 10 to 59%. This study improves system representation and results for large-scale modeling. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
28. Methodology for Exploring Water and Hydropower Operating Criteria That Simultaneously Improve Economic and Environmental Considerations.
- Author
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Ploussard, Quentin, Veselka, Thomas, and De Silva, Thushara
- Subjects
HYDROELECTRIC power plants ,MONTE Carlo method ,SEDIMENT transport ,ENVIRONMENTAL impact statements ,FISH growth - Abstract
Despite the reliability and flexibility of hydropower, the operation of hydroelectric power plants may have significant impacts on the downstream river system, including its water stage, sediment transport, and water temperature, ultimately affecting the ecology. To address these challenges, there is a need to identify water scheduling patterns that improve both hydropower economics and the environment relative to current operations. This paper presents a new methodology to explore promising operational criteria/rules that can achieve such improvements. Typical environmental impact statements and relicensing processes generally perform detailed site-specific analyses of a few alternatives that focus on reservoir water release operating rules and their associated environmental impacts. In contrast, the methodology presented in this article uses a widely applicable approach that explores a much larger solution space. This large set of potential alternatives can be represented in a multidimensional space for which one axis represents the economic value and the other axis quantify individual environmental impacts (e.g., sediment transport and fish growth), and they are explored via two approaches: a Monte Carlo simulation that identifies "win–win" alternatives and a multi-objective optimization problem that identifies Pareto-optimal alternatives. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
29. Análisis de la Integración del Hidrógeno en Sistemas Híbridos de Energía Renovable en el marco de Escenarios Energéticos.
- Author
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García, Andrés, Ángel, Enrique, Jaramilo, Andrés, and Ortega, Santiago
- Subjects
GREEN fuels ,HYDROGEN as fuel ,RENEWABLE energy sources ,LITERATURE reviews ,WIND power - Abstract
Copyright of Revista EIA is the property of Escuela de Ingenieria de Antioquia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2024
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- View/download PDF
30. Development of a Novel High Head Impulse Hydro Turbine.
- Author
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Aggidis, George, Židonis, Audrius, Burtenshaw, Luke, Dubois, Marc, Orritt, Stephen, Pickston, Dominic, Prigov, George, and Wilmot, Luke
- Abstract
The Pelton turbine has been widely regarded as the most efficient hydro turbine for high-head applications. However, the Pelton turbine buckets, especially the area commonly referred to as the 'splitter', are highly susceptible to erosion, drastically reducing efficiency over prolonged periods of time. This paper demonstrates a novel turbine idea that has been validated through both computational and experimental methods. This turbine addresses the issues associated with the erosion of the splitter through a redesign of the Pelton turbine to remove the need for a splitter and therefore potentially reducing downtime due to maintenance. The computational fluid dynamics (CFD) simulation results show that the turbine is capable of efficiencies greater than 82% with room for further improvement. The practical experimental results also show efficiencies within 6% of an optimized Pelton turbine. The results from this study indicate that through further optimization this turbine design could provide a means to produce power outputs similar to conventional Pelton turbines, with the added benefit of lower maintenance costs. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
31. Influence Analysis and Control Method of Ultra-Low Frequency Oscillation in a Hydro-Dominant Sending Power System with Wind Power Integration.
- Author
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Chen, Gang, Zeng, Xueyang, Shi, Huabo, Wang, Biao, Li, Gan, Jiang, Qin, Wang, Yongfei, and Li, Baohong
- Subjects
FREQUENCIES of oscillating systems ,WIND power ,ROBUST control ,RENEWABLE energy sources ,HIGH voltages ,RISK assessment - Abstract
To make clear the influence of renewable energy on ultra-low-frequency oscillation (ULFO) in a hydro-dominant system via an high voltage direct current (HVDC) transmission system, this paper studies the damping characteristics when wind power is integrated into the sending power system. The damping torque method is applied for the mechanism study and risk evaluation of ULFO. The study of the inner cause and outer performance proves that ULFO belongs to frequency oscillation rather than conventional power oscillation. According to the theoretical analysis, the suggested control mode is identified to reduce the risk of ULFO. Moreover, a robust controller is designed for wind units based on mixed H
2 /H∞ robust control theory, and the control method makes use of the fast response ability of the converter without compromising the primary frequency regulation ability. Finally, a simulation model of a hydro-dominant sending power system with wind integration is established in PSCAD Version 4.6 software. The simulations verify the proposed control can suppress ULFO effectively. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
32. Common Failures in Hydraulic Kaplan Turbine Blades and Practical Solutions.
- Author
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Khalid Mohammed Ridha, Waleed, Reza Kashyzadeh, Kazem, and Ghorbani, Siamak
- Subjects
HYDRAULIC turbines ,TURBINE blades ,FOREIGN bodies ,FRACTURE mechanics ,MANUFACTURING processes ,MATERIAL fatigue ,GAS power plants ,POWER plants - Abstract
Kaplan turbines, as one of the well-known hydraulic turbines, are generally utilized worldwide for low-head and high-flow conditions. Any failure in each of the turbine components can result in long-term downtime and high repair costs. In a particular case, if other parts are damaged due to the impact of the broken blades (e.g., the main shaft of the turbine), the whole power plant may be shut down. On the other hand, further research on the primary causes of failures in turbines can help improve the present failure evaluation methodologies in power plants. Hence, the main objective of this paper is to present the major causes of Kaplan turbine failures to prevent excessive damage to the equipment and provide practical solutions for them. In general, turbines are mainly subjected to both Internal Object Damage (IOD) and Foreign Object Damage (FOD). Accordingly, this paper presents a state-of-the-art review of Kaplan turbine failures related to material and physical defects, deficiencies in design, deficits in manufacturing and assembly processes, corrosion failures, fatigue failure, cavitation wear, types of cavitation in hydro turbines, hydro-abrasive problems, and hydro-erosion problems. Eventually, the authors have attempted to discuss practical hints (e.g., nanostructured coatings) to prevent damages and improve the performance of Kaplan turbines. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
33. Dynamic simulation and assessment of the ecological benefits of hydropower as an alternative energy for thermal power under ecological civilization construction: A case study of Fujian, China.
- Author
-
Zhang, Lihui, Chai, Jianxue, Zhu, Jinrong, and Zhao, Zhenli
- Subjects
ALTERNATIVE fuels ,WATER power ,HEAT ,DYNAMIC simulation ,CLEAN energy ,ECOLOGICAL assessment - Abstract
As ecological civilization construction receives growing attention in China, the eco‐friendliness of the power supply structure is becoming increasingly important. Thermal power and hydropower are the two major power sources in China. Hydropower has both positive and negative effects on the ecosystem. However, there are few studies on the comprehensive impact of hydropower on the ecosystem. Therefore, the main innovation of this article is to integrally and comprehensively study the impact of hydropower to propose recommendations for hydropower development. The study of hydropower's effects on the overall ecosystem including resources, the environment, and economic society reflects the integrity, and the simultaneous study of hydropower's positive and negative effects reflects the comprehensiveness. First, this paper constructs a system dynamics (SD) model that can analyze the impact of replacing thermal power with hydropower on the ecosystem and proposes an improved coupling coordination degree (CCD) model. Then, this paper takes the province of Fujian as an example for SD scenario simulation and proposes recommendations for each indicator in the ecology subsystem. Finally, this paper performs CCD analysis on subsystems of the ecology subsystem in different policy scenarios and provides suggestions for future hydropower development in Fujian. Results show that hydropower technology improvement and efficiency increase (HTIEI) is more conducive to the development of the overall ecosystem. The scientificity of the current hydropower policy in Fujian is proven through theoretical analysis, and further hydropower development proposals are proposed. This paper provides a basis for the formulation of power generation policies and promotes ecological civilization construction for Fujian. The proposed methods in this paper can also provide tools for policy research on clean energy power generation. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
34. The Water–Energy Nexus of Leakages in Water Distribution Systems.
- Author
-
Souza, Rui Gabriel, Barbosa, Alan, and Meirelles, Gustavo
- Subjects
WATER distribution ,WATER levels ,POWER resources ,WATER supply ,WATER use ,WATER leakage - Abstract
Leakages in water distribution systems (WDSs) profoundly affect their operations, elevating water production demand and treatment and pumping costs. Moreover, they strain the energy system by increasing power requirements at pumping stations. In regions heavily reliant on hydropower, such as Brazil, there is a nuanced implication: diminishing reservoir water levels due to increased WDS flow withdrawal. This not only immediately affects hydropower generation by reducing available head but, over time, may lead to interruptions in hydropower generation. This paper investigates the water–energy nexus, specifically focusing on WDS leakages in Brazil. It begins with an overview of the current situation and future outlook, considering evolving policies to enhance WDS efficiency and also the evaluation of different climate change scenarios. A more in-depth case study explores a reservoir utilized for both energy and water production. In this context, leakage management assumes critical importance, given the various water uses within the reservoir that impact the available energy and water resources. Overall, this study offers a comprehensive perspective on the water–energy nexus within WDSs, underscoring the critical importance of leakage control and its direct and indirect consequences, particularly on energy generation capacity, the environment, and the economy. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
35. Long-Term Hydropower Planning for Ethiopia: A Rolling Horizon Stochastic Programming Approach with Uncertain Inflow.
- Author
-
Dires, Firehiwot Girma, Amelin, Mikael, and Bekele, Getachew
- Subjects
STOCHASTIC programming ,STOCHASTIC models ,VALUE at risk ,DECISION making ,ELECTRICAL load shedding - Abstract
All long-term hydropower planning problems require a forecast of the inflow during the planning period. However, it is challenging to accurately forecast inflows for a year or more. Therefore, it is common to use stochastic models considering the uncertainties of the inflow. This paper compares deterministic and stochastic models in a weekly rolling horizon framework considering inflow uncertainty. The stochastic model is tested in both a risk-neutral and a risk-averse version. The rolling horizon framework helps make periodic decisions and update the information in each rolling week, which minimizes the errors in prolonged forecasts. The models aim to utilize the water stored in the rainy season throughout the year with minimum load shedding while storing as much water as possible at the end of the planning horizon. The Conditional Value at Risk ( C V a R ) risk measure is used to develop the risk-averse stochastic model. Three different risk measures are investigated to choose the risk measure that yields the best outcome in the risk-averse problem, and the two best measures are compared to a deterministic and risk-neutral model in a weekly rolling horizon framework. The results show that the risk-neutral and best risk-averse models perform almost equally and are better than the deterministic model. Hence, using a stochastic model would be an improvement to the actual planning performed in the Ethiopian and other African countries' power systems. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
36. Development versus displacement: re-examining India's hydropower-based development model.
- Author
-
Singha, Komol
- Subjects
COLD War, 1945-1991 ,SECONDARY analysis ,DAMS ,CIVIL society - Abstract
Since the early 1970s, as part of India's developmentalist agenda, a number of hydropower dams have been built in Manipur, the country's north-eastern-most State bordering Myanmar. However, none of the mega-dams built in the State have proven to be effective and fully functional today. Civil Society Organisations (CSOs) have been vocal in their opposition to mega-dams due to their negative effects on the environment and the livelihood security of local populations. Based on secondary data, historical antecedents, personal field information, and observable facts, this paper indicates that the Indian state's developmentalist approach begun in Manipur is roughly analogous to the western development model initiated during the cold war period. Despite overwhelming proof of Manipur's mega-dam failure, the Centre refuses to admit it and ignores CSO demands, and the failed mega-dams are unlikely to be decommissioned due to the Centre's clandestine objective. The hanger-on approach of several CSO leaders and local political figures who are subservient to the Centre's high command has gradually delegitimised and politicised genuine dam campaigns in Manipur. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
37. Integrating Open-Source Datasets to Analyze the Transboundary Water–Food–Energy–Climate Nexus in Central Asia.
- Author
-
De Keyser, Jan, Hayes, Daniel S., Marti, Beatrice, Siegfried, Tobias, Seliger, Carina, Schwedhelm, Hannah, Anarbekov, Oyture, Gafurov, Zafar, López Fernández, Raquel M., Ramos Diez, Ivan, Alapfy, Bertalan, Carey, Justine, Karimov, Bakhtiyor, Karimov, Erkin, Wagner, Beatrice, and Habersack, Helmut
- Subjects
WATER supply ,WATER management ,TRANSBOUNDARY waters ,HYDROLOGY ,FOOD security ,RESEARCH personnel - Abstract
In today's intrinsically connected world, the Water–Food–Energy–Climate Nexus (WFEC Nexus) concept provides a starting point for informed and transparent decision-making based on the trade-offs and synergies between different sectors, including aquatic ecosystems, food security, energy production, and climate neutrality. The WFEC Nexus approach is particularly applicable in regions requiring transboundary water management, such as Central Asia. Unfortunately, this region with unevenly distributed water resources—consisting of Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan, and Uzbekistan—is characterized by data scarcity, which limits informed decision-making. However, open-source geodata is becoming increasingly available. This paper aims to fill Central Asia's WFEC Nexus data gap by providing an overview of key data. We collected geodata through an integrated survey of stakeholders and researchers, stakeholder consultation, and literature screening. Sixty unique datasets were identified, belonging to one of six thematic categories: (1) climate, (2) hydrology, (3) geography and topography, (4) geomorphology, (5) ecology, and (6) anthropogenic uses. For each dataset, a succinct description, including a link to the online source, is provided. We also provide possible applications of using the presented datasets, demonstrating how they can assist in conducting various studies linked to the WFEC Nexus in Central Asia and worldwide. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
38. The limits of renewable energy.
- Author
-
Moriarty, Patrick and Honnery, Damon
- Subjects
NUCLEAR energy ,CLIMATE change ,GEOTHERMAL resources ,ENERGY futures ,EARTH (Planet) - Abstract
Planet Earth is simultaneously approaching a number of ecological and resource limits. The resulting uncertainties will heavily impact future energy choices, both the level of primary energy used globally and the shares of fossil, renewable and nuclear fuels in the energy mix. This paper reviews the possible futures for the various types of renewable energy. To be viable, all potential energy sources must be assessed on their energy return on energy invested (energy return). Given that renewable energy RE growth is considered important for sustainability reasons, renewable energy must be assessed on its ecologically sustainable or 'green' energy return, which includes the energy costs of ecosystem maintenance as input energy costs. The green energy return is accordingly much lower than the conventional value, so that ecologically sustainable renewable energy is unlikely to deliver anything near existing global energy use. The paper further argues that such constraints on renewable energy growth rates mean it cannot be a timely response to global climate change. The paper concludes that energy reductions will be essential, mainly in high energy use countries. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
39. Hydropower in the Energy Market in Poland and the Baltic States in the Light of the Challenges of Sustainable Development-An Overview of the Current State and Development Potential.
- Author
-
Chomać-Pierzecka, Ewa, Kokiel, Andrzej, Rogozińska-Mitrut, Joanna, Sobczak, Anna, Soboń, Dariusz, and Stasiak, Jacek
- Subjects
RENEWABLE energy sources ,RUSSIAN invasion of Ukraine, 2022- ,POWER resources ,CLEAN energy ,ENERGY shortages - Abstract
The energy crisis is affecting a number of countries, but particularly those that are heavily dependent on the traditional energy generation formula (e.g., Poland), as well as those neighbouring the territory of the ongoing war in Ukraine, i.e., Poland, Lithuania, Latvia and Estonia. With this in mind, the authors of this study decided to explore the issue of water energy as a source of green (cheap and environmentally safe) energy in these countries. The main objective of the paper is to review the available literature, which is needed to identify the role hydropower plays in energy security and energy transition in these energy markets. This paper is based on a review and critical appraisal of the available literature and studies together with an inference. The structure of the paper consists of an introduction, the main part of the review and conclusions. The geopolitical location and socio-economic conditions of the adopted set of countries, form the basis of the review of the existing literature on the theme explored and the substantive inference. The main findings of this review indicate that the literature is most strongly focused on the overall assessment of the energy transition of the adopted countries for review, where the hydropower thread is most often taken up as one source of renewable energy supply. Hydropower, due to its relatively low share in the energy systems of the adopted set of countries, is, according to the authors, insufficiently explored. The most significant gap relates to the aspect of the potential for hydropower development in these areas, considering both the construction of new hydropower plants and opportunities signalled in the literature for the modernisation or restoration of existing ones. In this respect, the need for analyses (studies and simulations) of hydropower development, considering the economic benefits associated with their development juxtaposed with the safety dimension of this course of action for the environment (analysis and assessment of environmental costs) is indicated, which is the main recommendation of the review. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
40. Scale-Resolving Hybrid RANS-LES Simulation of a Model Kaplan Turbine on a 400-Million-Element Mesh †.
- Author
-
Joßberger, Simon and Riedelbauch, Stefan
- Subjects
HYBRID computer simulation ,DRAFT tubes ,TURBINES ,SIMULATION methods & models ,COMPUTATIONAL fluid dynamics ,DIFFUSERS (Fluid dynamics) - Abstract
Double-regulated Kaplan turbines with adjustable guide vanes and runner blades offer a high degree of flexibility and good efficiency for a wide range of operating points. However, this also leads to a complex geometry and flow guidance with, for example, vortices of different sizes and strengths. The flow in a draft tube is especially challenging to simulate mainly due to flow phenomena, like swirl, separation and strong adverse pressure gradients, and a strong dependency on the upstream flow conditions. Standard simulation approaches with RANS turbulence models, a coarse mesh and large time step size often fail to correctly predict performance and can even lead to wrong tendencies in the overall behavior. To reveal occurring flow phenomena and physical effects, a scale-resolving hybrid RANS-LES simulation on a block structured mesh of about 400 million hexahedral elements of a double-regulated five-blade model Kaplan turbine is carried out. In this paper, first, the results of the ongoing simulation are presented. The major part of the simulation domain is running in LES mode and seems to be properly resolved. The validation of the simulation results with the experimental data shows mean deviations of less than 0.8% in the global results, i.e., total head and power, and a good visual agreement with the three-dimensional PIV measurements of the velocity in the cone and both diffuser channels of the draft tube. In particular, the trend of total head and the results for the draft tube differ significantly between the scale-resolving simulation and a standard RANS simulation. The standard RANS simulation exhibits a highly unsteady behavior of flow, which is not observed in the experiments or scale-resolving simulation. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
41. Assessment of Fiber Bragg Grating Sensors for Monitoring Shaft Vibrations of Hydraulic Turbines.
- Author
-
Sánchez-Botello, Xavier, Roig, Rafel, de la Torre, Oscar, Madrigal, Javier, Sales, Salvador, and Escaler, Xavier
- Subjects
HYDRAULIC turbines ,FIBER Bragg gratings ,MODE shapes ,DETECTORS ,AIR speed ,OPTICAL gratings ,ELECTROCHEMICAL cutting - Abstract
The structural dynamic response of hydraulic turbines needs to be continuously monitored to predict incipient failures and avoid catastrophic breakdowns. Current methods based on traditional off-board vibration sensors mounted on fixed components do not permit inferring loads induced on rotating parts with enough accuracy. Therefore, the present paper assesses the performance of fiber Bragg grating sensors to measure the vibrations induced on a rotating shaft–disc assembly partially submerged in water resembling a hydraulic turbine rotor. An innovative mounting procedure for installing the sensors is developed and tested, which consists of machining a thin groove along a shaft line to embed a fiber-optic array that can pass through the bearings. At the top of the shaft, a rotary joint is used to extract, in real time, the signals to the interrogator. The shaft strain distribution is measured with high spatial resolution at different rotating speeds in air and water. From this, the natural frequencies, damping ratios, and their associated mode shapes are quantified at different operating conditions. Additionally, the change induced in the modes of vibration by the rotation effects is well captured. All in all, these results validate the suitability of this new fiber-optic technology for such applications and its overall better performance in terms of sensitivity and spatial resolution relative to traditional equipment. The next steps will consist of testing this new sensing technology in actual full-scale hydraulic turbines. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
42. A Review of Gravitational Water Vortex Hydro Turbine Systems for Hydropower Generation.
- Author
-
Maika, Nosare, Lin, Wenxian, and Khatamifar, Mehdi
- Subjects
TURBINE blades ,RENEWABLE energy sources ,TURBINES ,JOB performance ,RURAL geography ,WATER power - Abstract
Hydropower is one of the most sustainable and desirable renewable energy sources. Gravitational water vortex hydro turbine (GWVHT) systems are one of the most suitable and sustainable renewable power generation devices for remote and rural areas, particularly in developing countries, owing to their small scales and low costs. There are various GWVHT systems with different configurations and various operating conditions. The main components of a GWVHT system include the inlet and outlet channels, a basin, and a turbine on which there are a number of blades attached. This paper presents a comprehensive review regarding the progress and development of various GWVHT systems, covering broad aspects of GWVHT systems, particularly various types of basins, inlet and outlet channels, turbines with blades which have different shapes, orientations, sizes, numbers, etc. The nature of the previous studies is summarised. The fundamentals of the vortex dynamics involved and the quantitative analysis of the performance of GWVHT systems are also described. The turbulence models and multiphase models used in some leading numerical simulation studies have been reviewed. As a case study, the implementation of a GWVHT system in PNG is presented. Based on the review of previous studies regarding GWVHT systems, the major issues and challenges are summarised, and some key topics are recommended for future research work on the performance of GWVHT systems. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
43. Analysis of System Balancing and Wind Power Curtailment Challenges in the Ethiopian Power System under Different Scenarios.
- Author
-
Nefabas, Kena Likassa, Mamo, Mengesha, and Söder, Lennart
- Abstract
In this paper, an hourly dispatch model was developed to analyze the system balancing and wind power curtailment challenges in the future of the Ethiopian electric power grid system. The developed model was validated using historical data and was used for the analysis of the grid system in 2030 with different scenarios. The model was used to examine the impacts of transmission capacity, regulation reserve requirement, and daily minimum generation of hydropower for irrigation with three cases of wind annual energy share of 14.5%, 17.8%, and 25.2%. Thus, the curtailment was found to be below 0.2%, 1.1%, and 9.8% for each case, respectively. The cost of wind energy increases in proportion to the percentage of curtailment and the increase in transmission line capacity. Reducing the minimum hydropower generation results in smaller wind power curtailment and better generation–consumption balancing. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
44. DEVELOPMENT OF THE ALTERNATIVE ENERGY MARKET: CASE OF CENTRAL EUROPE.
- Author
-
KOHUT-FERENS, Oksana and RYBCHUK, Roman
- Subjects
ALTERNATIVE fuels ,ENERGY industries ,RENEWABLE energy sources ,LABOR market ,EMPLOYMENT statistics - Abstract
The paper presents an analysis of the development of the alternative energy market between 2010 and 2022 in seven Central European countries, namely Poland, the Czech Republic, Slovakia, Romania, Lithuania, Hungary, and Bulgaria. Analyzing changes in electricity generation from hydro, solar, wind and bioresources makes it possible to comprehensively assess trends in the development of alternative energy. The countries of Central and Eastern Europe are economically and climatically similar to Ukraine, so studying the development of their renewable energy is of scientific value for the drafting of both Ukrainian and European energy strategies in the context of the transforming global energy system. Additionally, the article discusses the impact of renewable energy development on the labor market, outlining potential challenges and threats to regional labor markets. Research conclusions confirm the practical development and effective implementation of RES in the European energy system, even in countries that do not take the lead in generating energy from renewable sources, i.e., in Central Europe. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
45. Estimating Hydropower Generation Flexibilities of a Hybrid Hydro–Wind Power System: From the Perspective of Multi-Time Scales.
- Author
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Man, Xiaokun, Song, Hongyan, and Li, Huanhuan
- Subjects
HYBRID power systems ,WIND power ,WATER power ,ELECTRIC power systems ,POWER resources ,WIND pressure ,RENEWABLE energy sources - Abstract
The increasing penetration of wind energy in electric power systems leads to a great demand for flexible resources to regulate power fluctuations. This paper focuses on investigating the impacts of the operational flexibility of hydropower generation systems on reducing wind curtailment and load shedding in a hybrid hydro–wind power system. Considering timescale variabilities of wind power, the upward and downward regulation capabilities of hydro flexibility under sub-hour and hour dispatch scales are estimated. Based on developed flexible indicators, the ultimate access ratio of wind power penetration into the power system is obtained by using the estimated probability of insufficient regulation reserves. All these analyses are carried out under the wet and dry periods to better understand their differences with the hydro flexibility. The method and obtained results provide important guidance for the stable and high-efficiency operation of hybrid power systems. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
46. Trademark Application for "CALI-CHEK" Filed by Fluke.
- Subjects
ELECTRONIC equipment ,SOFTWARE upgrades ,SYSTEMS software ,SOFTWARE measurement ,COMPUTER equipment ,COMPUTER software testing ,ELECTRONIC spreadsheets - Abstract
Fluke, a company represented by Caldwell A. Camero, has filed a trademark application for "CALI-CHEK." The application includes goods and services related to measuring, counting, aligning, and calibrating industrial machinery, as well as software for data recording and analysis. Fluke also offers installation, maintenance, and repair services for sensors, software development, and quality control services. The owner of the application is Caldwell A. Camero, and the company is located in Everett, Washington. The trademark application is related to industries such as automotive, food and beverage, power plants, hydropower plants, printing, pulp and paper, rolling mills, and wind energy. [Extracted from the article]
- Published
- 2024
47. A Methodology for Protective Vibration Monitoring of Hydropower Units Based on the Mechanical Properties
- Author
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Rolf Gustavsson, Mattias Nässelqvist, and Jan-Olov Aidanpää
- Subjects
Engineering ,Bearing (mechanical) ,business.industry ,Stator ,Mechanical Engineering ,Rotational speed ,Structural engineering ,Accelerometer ,Research Papers ,Load cell ,Computer Science Applications ,law.invention ,Vibration ,Control and Systems Engineering ,law ,business ,Air gap (plumbing) ,Instrumentation ,Hydropower ,Information Systems - Abstract
Different methods are used to monitor and protect the hydropower unit from harmful operation modes. Eccentricities and shape deviations in generators [1], mass unbalances in rotors [2], dynamic flow properties in turbines [3], etc. cause radial loads on the bearings and supporting structures. Figure Figure11 presents the components in a hydropower unit. Demands on the unit's instrumentation are dependent upon the importance of the unit and the cost of outage. Some older units do not have an installed vibration monitoring system, but most units are equipped with shaft displacement sensors or accelerometers to monitor vibrations in the unit. There are also units equipped with air gap sensors that measure the distance between the generator's rotor and stator. In some hydropower units, load cells are installed inside the bearing or bearing bracket in order to monitor radial loads on the structure. Several different types of sensors and methods can be used to monitor vibrations in a hydropower unit; the key issue with vibration monitoring is to protect the machine and avoid outage. Fig. 1 Components in a hydropower unit The recommendations in various standards for permitted vibration level values are often used as an aid to determine and decide if a unit is to be stopped for maintenance. The standards ISO 7919-5 [4] and ISO 10816-5 [5] divide vibration levels into classes with increasing levels from Class A to Class D, where Class A is a good machine that does not need attention while Class D is a machine that should be stopped for immediate corrective action. The permitted levels for each class vary with the unit's rotational speed; a low speed permits higher values of vibration levels in each class, compared to high speed. According to Totir et al. [6], ISO 7919-5 and ISO 10816-5 are not sufficient as vibration monitoring standards. The recommended vibration levels for each class are based on the unit's rotational speed and statistical data; consideration of the physical properties of bearings and brackets is not taken, which strongly affect the relationship between the radial load and vibration levels and which vibration levels the components can withstand. The objective of this paper is to present a vibration monitoring methodology based on the physical properties of the hydropower units, i.e., based on the design criteria of the hydropower unit and the measured radial loads in the machine during operation. The structure of this paper is to first describe the theoretical background regarding how to determine vibrations and forces in hydropower units. Following this, an example of design criteria for hydropower units is presented. Subsequently, Secs. 4 and 5 present a proposed methodology for vibration monitoring and an example of how the methodology is applied to a hydropower unit. Finally, discussions and conclusions regarding the methodology are presented.
- Published
- 2013
48. Perspectives on the environmental implications of sustainable hydro-power: comparing countries, problems and approaches.
- Author
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Alfredsen, K., Helland, I. P., Martins, E. G., and Power, M.
- Subjects
SPECIES diversity ,FISH populations ,DEVELOPING countries ,COUNTRIES ,ECOSYSTEMS ,ADAPTIVE natural resource management - Abstract
Perspectives on the Environmental Implications of Sustainable Hydropower gathers scientific papers from three of the worlds most important hydropower producers to discuss aspects of sustainable hydropower and the means by which it can be studied and achieved. The papers examine the application and use of new technologies and protocols for studying hydropower, adaptive management and the implications and use of long-term data sets for minimizing hydropower impacts on fish populations. The papers include a cross section of biological and hydrological experts. The implicit among country comparisons highlight a number of common hydropower themes, particularly the need to expand from single species studies to include broader consideration of the ecosystem, the importance of maintaining habitat, trait and species diversity and the need for consistently collected long-term data sets. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
49. Importance of Variable Turbine Efficiency in Run‐Of‐River Hydropower Design Under Deep Uncertainty.
- Author
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Yildiz, Veysel, Brown, Solomon, and Rougé, Charles
- Subjects
TURBINE efficiency ,NET present value ,FACTORY design & construction ,SOCIOECONOMIC factors ,PLANT yields ,WATER power - Abstract
When less water is available, hydropower turbines are less efficient, or have to stop altogether. This reality is often neglected in recent work on the planning and operations of hydropower systems, despite widespread expected increases in drought intensity, frequency and duration. This paper is the first to integrate variable‐efficiency turbines into a hydropower plant design framework that accounts for design optimization as well as deep uncertainty in climatic and socio‐economic variables. Specifically, this framework focuses on leveraging multi‐objective robust decision making for the financially robust design of run‐of‐river hydropower plants, whose output is highly sensitive to flow variability. Application to five plants in Türkiye challenges two key design assumptions, use of net present value as a design objective and use of identical turbines. Instead, maximizing the benefit‐cost ratio yields plants with better financial viability over a range of plausible futures. They tend to have smaller capacity, and feature a small turbine that is well‐adapted to low‐flow periods. Another key insight is that socio‐economic uncertainties have as much or even more impact on robustness than climate conditions. In fact, these uncertainties have the potential to make many small hydropower projects too risky to build. Our findings are of considerable practical relevance at a time where 140 GW of unexploited small hydropower potential could help power the energy transition. They also highlight the need for similar research in reservoir‐based plants, considering over 3,000 such plants planned or in construction worldwide. Key Points: Traditional approaches to hydropower planning need to be revisited to account for the impact of a variable climate on turbine efficiencyMaximizing the benefit cost ratio rather than the net present value promotes smaller designs, better adapted to a drought‐prone worldSocio‐economic and climatic factors are both crucial to design financial robustness [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
50. AI-Based Scheduling Models, Optimization, and Prediction for Hydropower Generation: Opportunities, Issues, and Future Directions.
- Author
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Villeneuve, Yoan, Séguin, Sara, and Chehri, Abdellah
- Subjects
ARTIFICIAL intelligence ,WATER power ,RENEWABLE energy sources ,ARTIFICIAL neural networks ,SUSTAINABILITY ,IRRIGATION scheduling - Abstract
Hydropower is the most prevalent source of renewable energy production worldwide. As the global demand for robust and ecologically sustainable energy production increases, developing and enhancing the current energy production processes is essential. In the past decade, machine learning has contributed significantly to various fields, and hydropower is no exception. All three horizons of hydropower models could benefit from machine learning: short-term, medium-term, and long-term. Currently, dynamic programming is used in the majority of hydropower scheduling models. In this paper, we review the present state of the hydropower scheduling problem as well as the development of machine learning as a type of optimization problem and prediction tool. To the best of our knowledge, this is the first survey article that provides a comprehensive overview of machine learning and artificial intelligence applications in the hydroelectric power industry for scheduling, optimization, and prediction. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
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