Head losses in small hydropower plant trash racks (SHP

Directory of Open Access Journals (Sweden)

N. Walczak

2016-12-01

Full Text Available Small hydropower plants (SHP are technical facilities that are part of alternative energy sources [Paish 2002]. They are primarily characterised by low unit power (in Poland below 5 MW and are often constructed on existing barrages. Electrical current produced by these plants is used to meet local demand. Considering the exploitation of SHPs, it is important to ensure a stable flow through turbines. Aggidis et al. [2010] analysed SHP equipment costs depending on the turbine set. The turbines are protected against damage with trash racks applied for capturing water-borne detritus, such as plant debris carried by water. However, trash racks as solid equipment of SHPs cause head losses, and as a consequence reduce the efficiency of the system. These losses result not only from the spacing of bars, their shape and the technical condition of the inlet chamber, but also from plant debris, its nature, and the quantity of accumulated material that effectively limits the flow. The plant debris captured on trash racks is characterised by diversity in terms of species composition related to the vegetation period and the area where hydraulic facilities are located. Therefore, it is important to maintain trash racks clean by regular removal of the accumulated material. In this context, modernised and newly built power plants are fitted with mechanical cleaners. In older facilities, manual intervention for regular cleaning is required. The present study analyses how the bar shape and the orientation angle of trash racks as well as the accumulated plant debris affect head losses. The results were obtained from laboratory tests. The research examined the impact the inclination angle of trash racks (30°, 60° and 80° has on head loss values for three different shapes of bars (cylindrical, angled and flat rectangular and various weight portions of plant debris (0.25, 0.375 and 0.5 kg. The summarised losses were determined by measuring the difference in water

Dataset for case studies of hydropower unit commitment

Directory of Open Access Journals (Sweden)

Jinwen Wang

2018-06-01

Full Text Available This paper presents the data all needed for nine case studies of hydropower unit commitment, which determines the optimal operating zones and generating discharges of units after the quarter-hourly releases and water heads are derived by the operation of cascaded hydropower reservoirs. The power output function and feasible operating zones of units are provided, and optimization solvers are used to acquire the results in detail for the case studies, including the quarter-hourly generating discharges, power generations, as well as operating zones of individual units. Performance indices, including the spillage, energy production, and the low-efficiency generating rate, are summarized for all case studies and can be readily used for comparison between algorithms in future.

Joint irrigation districts hydropower assessment study. Final feasibility assessment report. Volume I

Energy Technology Data Exchange (ETDEWEB)

None

1979-02-01

In August 1978, the United States Department of Energy and the Turlock Irrigation District entered into a cooperative agreement for a Joint District's Low-Head Hydropower Assessment Study. The purpose of the agreement was to carry out a study of the hydropower potential at sites within the borders of the Turlock, Merced, South San Joaquin, and Oakdale Irrigation Districts in California. The required data were gathered and analyzed. The results of this study indicate the total potential small hydropower capacity with the Joint Districts is 19,560 kW installed with an annual energy generation of 68,561,800 kWh. This is equivalent to oil-savings of 118,616 barrels per y.

Siphon-based turbine - Demonstration project: hydropower plant at a paper factory in Perlen, Switzerland; Demonstrationsprojekt Saugheber - Turbinen. Wasserturbinenanlage Papierfabrik Perlen (WTA-PF)

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-07-01

This final report for the Swiss Federal Office of Energy (SFOE) describes the demonstration project that concerned the re-activation and refurbishing of a very low-head hydropower installation. The functional principles of the siphon-turbine used are explained and the potential for its use at many low-head sites examined. The authors are of the opinion that innovative technology and simple mechanical concepts could be used to reactivate out-of-use hydropower plant or be used to refurbish existing plant to provide increased efficiency and reliability. Various other points that are to be considered when planning the refurbishment of a hydropower plant such as retaining mechanical and hydraulic symmetry in the plant are listed and concepts for reducing operating costs are discussed. Figures on the three runner-regulated turbines installed in Perlen are quoted.

Development and optimization design of pit turbine with super low-head

International Nuclear Information System (INIS)

Yang, C X; Li, X X; Huang, F J; Zheng, Y; QZhou, D

2012-01-01

Tubular turbines have many advantages such as large flow, high-speed, high efficiency, wide and high efficiency area, compact structure, simple layout, etc. With those advantages, tubular turbine is becoming one of the most economic and suitable types of turbines to develop low head hydraulic resources. According to the general situation of the hydropower station in the north of Jiangsu, a super low head pit turbine which head is set as about 2m is developed by the research to utilize the low head hydraulic resource.The CFD technology was used to calculate the flow field. The computing zone was meshed with unstructured gird. The whole flow passage of shaft type tubular turbine was calculated by 3-d steady turbulent numerical simulation. The detail of flowthrough the whole flowpassage was attained and the influence to the turbine's performance was analyzed by the low head runner blade's various diameters, airfoils and setting angles. The best turbine runner was obtained by considering all the methods. Meeting the station's requirements, the results show that the runner exhibits the highest performance in the efficiency, hydraulic loss and static pressure sides with 1.75m diameter, optimized airfoil and 23 degree setting angle. The developed super low head pit turbine shows highest efficiency under the design condition of 2.1m water head and 10m 3 /s flow rate. GD-WS-35 turbine model test was carried out tostudy the performance of the turbine. On the basis ofmodel transformation principle,the numerical simulationresultof GD-WS-175turbine was compared with the model results. It's showed that the model test result is basically consistent with numerical simulationresult. The producing error in the numerical computation is not easy to control. The efficiency's error range is ±3%.

Alpine hydropower in a low carbon economy: Assessing the local implication of global policies

Science.gov (United States)

Anghileri, Daniela; Castelletti, Andrea; Burlando, Paolo

2016-04-01

In the global transition towards a more efficient and low-carbon economy, renewable energy plays a major role in displacing fossil fuels, meeting global energy demand while reducing carbon dioxide emissions. In Europe, Variable Renewable Sources (VRS), such as wind and solar power sources, are becoming a relevant share of the generation portfolios in many countries. Beside the indisputable social and environmental advantages of VRS, on the short medium term the VRS-induced lowering energy prices and increasing price's volatility might challenge traditional power sources and, among them, hydropower production, because of smaller incomes and higher maintenance costs associated to a more flexible operation of power systems. In this study, we focus on the Swiss hydropower sector analysing how different low-carbon targets and strategies established at the Swiss and European level might affect energy price formation and thus impact - through hydropower operation - water availability and ecosystems services at the catchment scale. We combine a hydrological model to simulate future water availability and an electricity market model to simulate future evolution of energy prices based on official Swiss and European energy roadmaps and CO2 price trends in the European Union. We use Multi-Objective optimization techniques to design alternative hydropower reservoir operation strategies, aiming to maximise the hydropower companies' income or to provide reliable energy supply with respect to the energy demand. This integrated model allows analysing to which extent global low-carbon policies impact reservoir operation at the local scale, and to gain insight on how to prioritise compensation measures and/or adaptation strategies to mitigate the impact of VRS on hydropower companies in increasingly water constrained settings. Numerical results are shown for a real-world case study in the Swiss Alps.

The potential micro-hydropower projects in Nakhon Ratchasima province, Thailand

International Nuclear Information System (INIS)

Kosa, Preeyaphorn; Chinkulkijniwat, Avirut; Horpibulsuk, Suksun; Kulworawanichpong, Thanatchai; Srivoramas, Rerkchai; Teaumroong, Neung

2011-01-01

At present, fossil fuel energy is commonly used in developing countries, including Thailand. The tendency to use fossil fuel energy is continuously increasing, and the price of fossil fuels is rising. Thus, renewable energy is of interest. Hydropower is one of the oldest renewable energy forms known and one of the best solutions for providing electricity to rural communities. The present paper aims to determine the potential micro-hydropower sites that could provide more than 50 kW but not over 10 MW in Nakhon Ratchasima Province, Thailand. Both reservoir and run-of-the-river schemes are considered for the assessment of potential micro-hydropower sites. For the reservoir scheme, the discharge in the reservoir is employed for generating micro-hydropower electricity. This installation can be carried out without major modifications to the dam. The run-of-the-river scheme diverts water flow from the river mainstream to the intake via a pressure pipe or an open canal, which is then conveyed to the turbine via a penstock to generate electricity. The results showed that there are 6 suitable projects for the reservoir scheme and 11 suitable projects for the run-of-the-river. The maximum power load was 6000 kW and 320 kW for the reservoir and the run-of-the-river schemes, respectively. Hydropower from the run-of-the-river scheme is more suitable than hydropower from the reservoir scheme because of the many mountains in this province. The designed head for the run-of-the-river scheme is thus generally higher than that for the reservoir scheme. Because stream flow during the dry season is very low, electricity can only be produced in the wet season. This research is a pilot study to determine the potential sites of micro-hydropower projects. (author)

Technology Roadmap: Hydropower

Energy Technology Data Exchange (ETDEWEB)

NONE

2012-07-01

Hydropower could double its contribution by 2050, reaching 2,000 GW of global capacity and over 7,000 TWh. This achievement, driven primarily by the quest of clean electricity, could prevent annual emissions of up to 3 billion tonnes of CO2 from fossil-fuel plants. The bulk of this growth would come from large plants in emerging economies and developing countries. Hydroelectricity’s many advantages include reliability, proven technology, large storage capacity, and very low operating and maintenance costs. Hydropower is highly flexible, a precious asset for electricity network operators, especially given rapid expansion of variable generation from other renewable energy technologies such as wind power and photovoltaics. Many hydropower plants also provide flood control, irrigation, navigation and freshwater supply. The technology roadmap for Hydropower details action needed from policy makers to allow hydroelectric production to double, and addresses necessary conditions, including resolving environmental issues and gaining public acceptance.

A light left in the dark: The practice and politics of pico-hydropower in the Lao PDR

NARCIS (Netherlands)

Smits, M.; Bush, S.R.

2010-01-01

The article describes the widespread use of an estimated 60,000 low-head pico-hydropower turbines and well-developed networks of supply and support in the Northern part of the Lao People's Democratic Republic (Lao PDR). This apparent widespread use is contrasted with the policy narratives of key

A light left in the dark: The practice and politics of pico-hydropower in the Lao PDR

International Nuclear Information System (INIS)

Smits, Mattijs; Bush, Simon R.

2010-01-01

The article describes the widespread use of an estimated 60,000 low-head pico-hydropower turbines and well-developed networks of supply and support in the Northern part of the Lao People's Democratic Republic (Lao PDR). This apparent widespread use is contrasted with the policy narratives of key actors in the government, multilateral organisations and the private sector which show an often simplified and overly negative attitude towards pico-hydropower. Based on empirical research carried out in three upland districts and the capital, Vientiane, the paper critically investigates the apparent disjuncture between policy and practice by placing pico-hydropower within the broader political context of rural electrification in the Lao PDR. It is argued that the neglect of pico-hydropower and other off-grid household electrification technologies is a result of an endemic lack of information on which to base policy decisions, the orientation of the government to facilitate large scale foreign investment in large hydropower dams, the universal applicability of solar home systems, and the broader state agenda of centralisation and control over service provision to remote upland areas.

Hydropower

DEFF Research Database (Denmark)

Fenhann, Jørgen Villy; Kofoed, Jens Peter

2010-01-01

This chapter gives an overview of the various forms of hydropower: conventional hydropower, marine currents, tides, power from salinity gradients, ocean thermal energy conversion and wave power.......This chapter gives an overview of the various forms of hydropower: conventional hydropower, marine currents, tides, power from salinity gradients, ocean thermal energy conversion and wave power....

Life cycle greenhouse gas emissions estimation for small hydropower schemes in India

International Nuclear Information System (INIS)

Varun; Prakash, Ravi; Bhat, I.K.

2012-01-01

This paper presents for the first time correlations for greenhouse gas (GHG) emissions from small hydropower schemes in India. In this paper an attempt has been made to develop life cycle GHG emissions correlations for three different types of small hydropower schemes (run-of river, canal based and dam-toe) in India. It has been found out that GHG emissions depend on the head and capacity of the small hydropower project. The results obtained from correlations show good agreement with the estimated results using EIO-LCA (Economic Input–Output-Life Cycle Assessment) technique. These correlations may be useful for the development of new small hydropower (SHP) schemes, as they can be used to predict life cycle GHG emissions based on capacity, head and type of SHP schemes. -- Highlights: ► A study has been carried out for the Life Cycle Greenhouse gas emissions estimation for SHP schemes in India. ► Around 145 SHP schemes have been studied and their GHG emissions have been estimated. ► Based upon these results correlations have been developed for three different types of SHP schemes.

Design of a reliable and low-cost stand-alone micro hydropower station

Energy Technology Data Exchange (ETDEWEB)

Kusakana, K.; Munda, J.L. [Tshwane Univ. of Technology, Pretoria (South Africa)

2008-07-01

A stand-alone micro-hydropower station was presented. The plant was comprised of a squirrel cage induction machine coupled to a Kaplan water turbine. Power converters were used to control the variable frequency and voltage outputs of the generator caused by variations in water flow. The hydropower plant was installed a farm in the Kwazulu-Natal region of South Africa, and was designed to provide electricity in relation to the low power demand of users in the region as well as according to the site's hydrology and topology. Load forecasts for the 8 houses using the system were conducted. A generator with a higher output than the average power needed to feed the load was selected in order to ensure load supply during peak demand. The system was designed to shore energy generated during off-peak periods in batteries. An AC-DC-AC converter was used as an interface between the generator and the load in order to ensure voltage and frequency stabilization. Simulations of plant components were conducted to demonstrate output power supply during water flow variations. Results of the modelling study indicated that power converters are needed to stabilize generator outputs. The hydropower design is a cost-effective means of supplying power to low-income households. 10 refs., 2 tabs., 7 figs.

DOE Hydropower Program Biennial Report for FY 2005-2006

Energy Technology Data Exchange (ETDEWEB)

Sale, Michael J [ORNL; Cada, Glenn F [ORNL; Acker, Thomas L. [Northern Arizona State University and National Renewable Energy Laboratory; Carlson, Thomas [Pacific Northwest National Laboratory (PNNL); Dauble, Dennis D. [Pacific Northwest National Laboratory (PNNL); Hall, Douglas G. [Idaho National Laboratory (INL)

2006-07-01

. Completed a state-of-the-science review of hydropower optimization methods and published reports on alternative operating strategies and opportunities for spill reduction. Carried out feasibility studies of new environmental performance measurements of the new MGR turbine at Wanapum Dam, including measurement of behavioral responses, biomarkers, bioindex testing, and the use of dyes to assess external injuries. Evaluated the benefits of mitigation measures for instream flow releases and the value of surface flow outlets for downstream fish passage. Refined turbulence flow measurement techniques, the computational modeling of unsteady flows, and models of blade strike of fish. Published numerous technical reports, proceedings papers, and peer-reviewed literature, most of which are available on the DOE Hydropower website. Further developed and tested the sensor fish measuring device at hydropower plants in the Columbia River. Data from the sensor fish are coupled with a computational model to yield a more detailed assessment of hydraulic environments in and around dams. Published reports related to the Virtual Hydropower Prospector and the assessment of water energy resources in the U.S. for low head/low power hydroelectric plants. Convened a workshop to consider the environmental and technical issues associated with new hydrokinetic and wave energy technologies. Laboratory and DOE staff participated in numerous workshops, conferences, coordination meetings, planning meetings, implementation meetings, and reviews to transfer the results of DOE-sponsored research to end-users.

A low-cost, ultra-fast and ultra-low noise preamplifier for silicon avalanche photodiodes

Science.gov (United States)

Gasmi, Khaled

2018-02-01

An ultra-fast and ultra-low noise preamplifier for amplifying the fast and weak electrical signals generated by silicon avalanche photodiodes has been designed and developed. It is characterized by its simplicity, compactness, reliability and low cost of construction. A very wide bandwidth of 300 MHz, a very good linearity from 1 kHz to 280 MHz, an ultra-low noise level at the input of only 1.7 nV Hz-1/2 and a very good stability are its key features. The compact size (70 mm  ×  90 mm) and light weight (45 g), as well as its excellent characteristics, make this preamplifier very competitive compared to any commercial preamplifier. The preamplifier, which is a main part of the detection system of a homemade laser remote sensing system, has been successfully tested. In addition, it is versatile and can be used in any optical detection system requiring high speed and very low noise electronics.

Land Systems Impacts of Hydropower Development

Science.gov (United States)

Wu, G. C.; Torn, M. S.

2016-12-01

Hydropower is often seen as the low-cost, low-carbon, and high-return technology for meeting rising electricity demand and fueling economic growth. Despite the magnitude and pace of hydropower expansion in many developing countries, the potential land use and land cover change (LULCC), particularly indirect LULCC, resulting from hydropower development is poorly understood. Hydropower-driven LULCC can have multiple impacts ranging from global and local climate modification (e.g., increased extreme precipitation events or increased greenhouse gas emissions), ecosystem degradation and fragmentation, to feedbacks on hydropower generation (e.g., increased sedimentation of the reservoir). As a result, a better understanding of both direct and indirect LULCC impacts can inform a more integrated and low-impact model for energy planning in countries with transitioning or growing energy portfolios. This study uses multi-scale remote sensing imagery (Landsat, MODIS, fine-resolution commercial imagery) to estimate LULCC from past hydropower projects intended primarily for electricity generation in 12 countries in Africa, South and Central America, South Asia, and Southeast Asia. It is important to examine multiple locations to determine how socio-political and environmental context determines the magnitude of LULCC. Previous studies have called for the need to scale-up local case studies to examine "cumulative impacts" of multiple development activities within a watershed. We use a pre-test/post-test quasi-experimental design using a time series of classified images and vegetation indices before and after hydropower plant construction as the response variable in an interrupted time series regression analysis. This statistical technique measures the "treatment" effect of hydropower development on indirect LULCC. Preliminary results show land use change and landscape fragmentation following hydropower development, primarily agricultural and urban in nature. These results suggest

The chemistry of ultra-low concentrations

International Nuclear Information System (INIS)

Vertes, Attila; Kiss, Istvan

1987-01-01

Methods for the separation and enrichment of radionuclides in the ultra-low concentration range (coprecipitation, adsorption of radioactive substances on crystals) are disscussed in this chapter of the textbook. The properties and behaviour of ultra-dilute solutions, radiocolloids and the electrochemistry of ultra-dilute solution are also overviewed

Acceptance test procedure for the ultra high pressure bore head for use in the self-installing liquid observation well

International Nuclear Information System (INIS)

Hertelendy, N.A.

1995-01-01

In order to monitor waste stored in single-shell tanks, liquid observation wells (LOWs) are installed to permit periodic insertion of instrumentation probes to evaluate the waste cross sections. An ultra high pressure water bore head, developed for installing instrument trees, was adapted for use with the LOWs. The modification facilitates the removal of the high pressure water feed system after installation. This document describes a series of tests that ensures that the design meets all the functional requirements

Ultra-low-power and ultra-low-cost short-range wireless receivers in nanoscale CMOS

CERN Document Server

Lin, Zhicheng; Martins, Rui Paulo

2016-01-01

This book provides readers with a description of state-of-the-art techniques to be used for ultra-low-power (ULP) and ultra-low-cost (ULC), short-range wireless receivers. Readers will learn what is required to deploy these receivers in short-range wireless sensor networks, which are proliferating widely to serve the internet of things (IoT) for “smart cities.” The authors address key challenges involved with the technology and the typical tradeoffs between ULP and ULC. Three design examples with advanced circuit techniques are described in order to address these trade-offs, which specially focus on cost minimization. These three techniques enable respectively, cascading of radio frequency (RF) and baseband (BB) circuits under an ultra-low-voltage (ULV) supply, cascoding of RF and BB circuits in current domain for current reuse, and a novel function-reuse receiver architecture, suitable for ULV and multi-band ULP applications such as the sub-GHz ZigBee. ·         Summarizes the state-of-the-art i...

The potential impacts of climate change on hydropower: An ...

African Journals Online (AJOL)

Osborne

Climate change has the potential to affect hydropower generation by either increasing or reducing flows (discharge) and the head. .... evapotranspiration levels thus reducing the runoff. (Harrison et al., 1998). Therefore .... The discharge rates are determined by factors such as climate, vegetation, soil type, drainage basin ...

The water footprint of electricity from hydropower

NARCIS (Netherlands)

Mekonnen, Mesfin; Hoekstra, Arjen Ysbert

Hydropower accounts for about 16% of the world’s electricity supply. Although dams often have big environmental and social impacts, proponents of hydropower regard it as a comparatively clean, low-cost and renewable form of energy. It has been debated whether hydroelectric generation is merely an

Encoded low swing for ultra low power interconnect

NARCIS (Netherlands)

Krishnan, R.; Pineda de Gyvez, J.

2003-01-01

We present a novel encoded-low swing technique for ultra low power interconnect. Using this technique and an efficient circuit implementation, we achieve an average of 45.7% improvement in the power-delay product over the schemes utilizing low swing techniques alone, for random bit streams. Also, we

Hydropower

CSIR Research Space (South Africa)

Jonker Klunne, W

2012-10-01

Full Text Available Hydropower is currently the most common source of renewable energy, accounting for more than 3,400 terawatts, or about 16 percent of global electricity production, in 2010. As hydropower uses a fuel—water from the hydrologic cycle...

Optimised deployment of hydro-power generation facilities

International Nuclear Information System (INIS)

Werlen, K.

2004-01-01

This article discusses how the opening-up of the European electricity market has led to the creation of more room for manoeuvre in the deployment of the generation capacity of dam and pumped-storage-based hydropower facilities and low-head power stations. Software tools for the optimisation of the operation of power generation facilities that can take care of complex hydraulic interdependencies are described. The use of the software for the assessment of new installations being planned or of older installations being extended is examined. The influence of climatic conditions, market prices for power, the general requirements placed on the system and other influences on financial gain are looked at. The article makes recommendations on those factors influencing the design of the software and for its optimal use in practice

Hydropower assessment of Bolivia—A multisource satellite data and hydrologic modeling approach

Science.gov (United States)

Velpuri, Naga Manohar; Pervez, Shahriar; Cushing, W. Matthew

2016-11-28

This study produced a geospatial database for use in a decision support system by the Bolivian authorities to investigate further development and investment potentials in sustainable hydropower in Bolivia. The study assessed theoretical hydropower of all 1-kilometer (km) stream segments in the country using multisource satellite data and a hydrologic modeling approach. With the assessment covering the 2 million square kilometer (km2) region influencing Bolivia’s drainage network, the potential hydropower figures are based on theoretical yield assuming that the systems generating the power are 100 percent efficient. There are several factors to consider when determining the real-world or technical power potential of a hydropower system, and these factors can vary depending on local conditions. Since this assessment covers a large area, it was necessary to reduce these variables to the two that can be modeled consistently throughout the region, streamflow or discharge, and elevation drop or head. First, the Shuttle Radar Topography Mission high-resolution 30-meter (m) digital elevation model was used to identify stream segments with greater than 10 km2 of upstream drainage. We applied several preconditioning processes to the 30-m digital elevation model to reduce errors and improve the accuracy of stream delineation and head height estimation. A total of 316,500 1-km stream segments were identified and used in this study to assess the total theoretical hydropower potential of Bolivia. Precipitation observations from a total of 463 stations obtained from the Bolivian Servicio Nacional de Meteorología e Hidrología (Bolivian National Meteorology and Hydrology Service) and the Brazilian Agência Nacional de Águas (Brazilian National Water Agency) were used to validate six different gridded precipitation estimates for Bolivia obtained from various sources. Validation results indicated that gridded precipitation estimates from the Tropical Rainfall Measuring Mission

Ultra low bit-rate speech coding

CERN Document Server

Ramasubramanian, V

2015-01-01

"Ultra Low Bit-Rate Speech Coding" focuses on the specialized topic of speech coding at very low bit-rates of 1 Kbits/sec and less, particularly at the lower ends of this range, down to 100 bps. The authors set forth the fundamental results and trends that form the basis for such ultra low bit-rates to be viable and provide a comprehensive overview of various techniques and systems in literature to date, with particular attention to their work in the paradigm of unit-selection based segment quantization. The book is for research students, academic faculty and researchers, and industry practitioners in the areas of speech processing and speech coding.

Hydropower development trends from a technological paradigm perspective

International Nuclear Information System (INIS)

Xu, Jiuping; Ni, Ting; Zheng, Bobo

2015-01-01

Highlights: • We propose a novel concept of hydropower development technological paradigm. • We create a data analysis system to visualize the keyword foci. • Future trajectories include hybrid power systems and resources from seawater. • The HDTP consists of a three-stage evolution and a policy framework. • The HDTP provides a how-to-do solution for the soft path. - Abstract: Hydropower has long been considered the backbone of the power generation sector in low-carbon and sustainable energy systems. Yet, as reliance on hydropower has been generally declining, the world is awakening to the need to fundamentally rethink the way hydropower is developed and managed. The paper proposes a systematic methodology to research the development trends and find a more sustainable hydropower path. Literature mining using the data analysis system and the technological paradigm theory were adopted to conduct the research. The keyword visualization results were found to meet the laws for the three phases of the technological paradigm. Specific key areas, such as small hydropower plants, hybrid power systems, and hydropower from seawater were identified as past, present and near future trajectories. To further accelerate hydropower development, specific subsidies and incentives need to be provided in areas such as capital costs and technological support. The study paves the way for a soft path solution which complements the hard path in hydropower field

Ultra-low power integrated circuit design circuits, systems, and applications

CERN Document Server

Li, Dongmei; Wang, Zhihua

2014-01-01

This book describes the design of CMOS circuits for ultra-low power consumption including analog, radio frequency (RF), and digital signal processing circuits (DSP). The book addresses issues from circuit and system design to production design, and applies the ultra-low power circuits described to systems for digital hearing aids and capsule endoscope devices. Provides a valuable introduction to ultra-low power circuit design, aimed at practicing design engineers; Describes all key building blocks of ultra-low power circuits, from a systems perspective; Applies circuits and systems described to real product examples such as hearing aids and capsule endoscopes.

Ultra Low Concentration Adsorption Equilibria

National Research Council Canada - National Science Library

Mahle, John J; Buettner, Leonard C; LeVan, M. D; Schindler, Bryan J

2006-01-01

.... Specifically this work focuses on novel experimental and modeling methods to characterize and predict at ultra-low chemical vapor concentrations the protection afforded by adsorption-based vapor filtration systems...

Summary Report of Advanced Hydropower Innovations and Cost Reduction Workshop at Arlington, VA, November 5 & 6, 2015

Energy Technology Data Exchange (ETDEWEB)

O' Connor, Patrick [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Rugani, Kelsey [Kearns & West, Inc., San Francisco, CA (United States); West, Anna [Kearns & West, Inc., San Francisco, CA (United States)

2016-03-01

On behalf of the U.S. Department of Energy (DOE) Wind and Water Power Technology Office (WWPTO), Oak Ridge National Laboratory (ORNL), hosted a day and half long workshop on November 5 and 6, 2015 in the Washington, D.C. metro area to discuss cost reduction opportunities in the development of hydropower projects. The workshop had a further targeted focus on the costs of small, low-head1 facilities at both non-powered dams (NPDs) and along undeveloped stream reaches (also known as New Stream-Reach Development or “NSD”). Workshop participants included a cross-section of seasoned experts, including project owners and developers, engineering and construction experts, conventional and next-generation equipment manufacturers, and others to identify the most promising ways to reduce costs and achieve improvements for hydropower projects.

Hydropower Baseline Cost Modeling

Energy Technology Data Exchange (ETDEWEB)

O' Connor, Patrick W. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Zhang, Qin Fen [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); DeNeale, Scott T. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Chalise, Dol Raj [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Centurion, Emma E. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2015-01-01

Recent resource assessments conducted by the United States Department of Energy have identified significant opportunities for expanding hydropower generation through the addition of power to non-powered dams and on undeveloped stream-reaches. Additional interest exists in the powering of existing water resource infrastructure such as conduits and canals, upgrading and expanding existing hydropower facilities, and the construction new pumped storage hydropower. Understanding the potential future role of these hydropower resources in the nation’s energy system requires an assessment of the environmental and techno-economic issues associated with expanding hydropower generation. To facilitate these assessments, this report seeks to fill the current gaps in publically available hydropower cost-estimating tools that can support the national-scale evaluation of hydropower resources.

Dispatch Method for Independently Owned Hydropower Plants in the Same River Flow

Directory of Open Access Journals (Sweden)

Slavko Krajcar

2012-09-01

Full Text Available This paper proposes a coexistence model for two independent companies both operating hydropower plants in the same river flow, based on a case study of the Cetina river basin in Croatia. Companies are participants of the day-ahead electricity market. The incumbent company owns the existing hydropower plants and holds concessions for the water. The new company decides to build a pump storage hydropower plant that uses one of the existing reservoirs as its lower reservoir. Meeting reservoir water balance is affected by decisions by both companies which are independently seeking maximal profit. Methods for water use settlement and preventing of spillage are proposed. A mixed-integer linear programming approach is used. Head effects on output power levels are also considered. Existences of dispatches that satisfy both companies are shown.

Steady and transient regimes in hydropower plants

Science.gov (United States)

Gajic, A.

2013-12-01

Hydropower plant that has been in operation for about 30 years has to be reconstructed. They have already installed 12 Kaplan turbines, the largest in the world at that time. The existing CAM relationship was determined based on hydraulic model tests and checked by efficiency on-site tests. It was also tested based on turbine bearing vibrations. In order to discover vibrations and long cracks on stay vanes detailed on-site measurements were performed. Influence of the modification of the trailing edges on the dynamic stresses of the stay vanes is also shown. In order to improve power output transient regimes were analyzed, both experimentally and numerically. Reversible hydropower plant, a pioneer in Europe since it was the first Pump storage power plant constructed with the highest head pump-turbines in the world. Analyses of transient regimes discover some problems with S-shaped characteristics coupled with non-symmetrical penstock.

Steady and transient regimes in hydropower plants

International Nuclear Information System (INIS)

Gajic, A

2013-01-01

Hydropower plant that has been in operation for about 30 years has to be reconstructed. They have already installed 12 Kaplan turbines, the largest in the world at that time. The existing CAM relationship was determined based on hydraulic model tests and checked by efficiency on-site tests. It was also tested based on turbine bearing vibrations. In order to discover vibrations and long cracks on stay vanes detailed on-site measurements were performed. Influence of the modification of the trailing edges on the dynamic stresses of the stay vanes is also shown. In order to improve power output transient regimes were analyzed, both experimentally and numerically. Reversible hydropower plant, a pioneer in Europe since it was the first Pump storage power plant constructed with the highest head pump-turbines in the world. Analyses of transient regimes discover some problems with S-shaped characteristics coupled with non-symmetrical penstock

Water-quality impact assessment for hydropower

International Nuclear Information System (INIS)

Daniil, E.I.; Gulliver, J.; Thene, J.R.

1991-01-01

A methodology to assess the impact of a hydropower facility on downstream water quality is described. Negative impacts can result from the substitution of discharges aerated over a spillway with minimally aerated turbine discharges that are often withdrawn from lower reservoir levels, where dissolved oxygen (DO) is typically low. Three case studies illustrate the proposed method and problems that can be encountered. Historic data are used to establish the probability of low-dissolved-oxygen occurrences. Synoptic surveys, combined with downstream monitoring, give an overall picture of the water-quality dynamics in the river and the reservoir. Spillway aeration is determined through measurements and adjusted for temperature. Theoretical computations of selective withdrawal are sensitive to boundary conditions, such as the location of the outlet-relative to the reservoir bottom, but withdrawal from the different layers is estimated from measured upstream and downstream temperatures and dissolved-oxygen profiles. Based on field measurements, the downstream water quality under hydropower operation is predicted. Improving selective withdrawal characteristics or diverting part of the flow over the spillway provided cost-effective mitigation solutions for small hydropower facilities (less than 15 MW) because of the low capital investment required

Hydropower in China at present and its further development

Energy Technology Data Exchange (ETDEWEB)

Chang, XiaoLin; Zhou, Wei [State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan 430072 (China); Liu, Xinghong [School of Civil and Architectural Engineering, Wuhan University, Wuhan 430072 (China)

2010-11-15

At present, China's economic development faces energy challenge, and the appropriate solution of energy bottleneck is the key to healthy, rapid and sustainable development. China's gross amount of hydraulic resource ranks first in the world; however, because of low level of development, hydraulic resource has a broad development prospect. Now, China's hydropower development is in its peak period. By the end of 2004, the gross installed hydropower capacity of China broke through 100 million kW. From there, it has remained in the top slot worldwide. The vigorous development of hydropower is necessary because of the energy shortage and environmental pollution in China in order to attain sustainable development of China's economy. Abundant hydraulic resource, huge market demands, the strategy of western development and the favorable environment of economic development provide hydropower construction with unprecedented advantages and opportunities. Chins hydropower development aims at an installed hydropower capacity of up to 194 million kW by 2010, accounting for 23.1% of the gross installed power capacity and 35% of hydropower resource. Finally, we present the general condition of Three Gorges project as well as the new mode of hydropower development of Three Gorges Project Corporation, i.e., cascade development. (author)

Hydropower in Estonia

International Nuclear Information System (INIS)

Raesaar, Peeter

1997-01-01

Long life practice has proved that small hydropower is not a beaten track in the global energy field. Before the Second World War small hydropower was rather well developed in Estonia as well. Being neglected during the years of Soviet occupation, it is rather important to help it to regain its position in the Estonian energy system once again. Our hydropower potential is not big, but it has got a good established position as an energy saving measure. By now we have some good examples of restored hydropower stations on commercial basis to be optimistic about the future

Small Hydropower in the United States

Energy Technology Data Exchange (ETDEWEB)

Hadjerioua, Boualem [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Johnson, Kurt [Telluride Energy, Telluride, CO (United States)

2015-09-01

Small hydropower, defined in this report as hydropower with a generating capacity of up to 10 MW typically built using existing dams, pipelines, and canals has substantial opportunity for growth. Existing small hydropower comprises about 75% of the current US hydropower fleet in terms of number of plants. The economic feasibility of developing new small hydropower projects has substantially improved recently, making small hydropower the type of new hydropower development most likely to occur. In 2013, Congress unanimously approved changes to simplify federal permitting requirements for small hydropower, lowering costs and reducing the amount of time required to receive federal approvals. In 2014, Congress funded a new federal incentive payment program for hydropower, currently worth approximately 1.5 cents/kWh. Federal and state grant and loan programs for small hydropower are becoming available. Pending changes in federal climate policy could benefit all renewable energy sources, including small hydropower. Notwithstanding remaining barriers, development of new small hydropower is expected to accelerate in response to recent policy changes.

Hydropower's future, the environment, and global electricity systems

Energy Technology Data Exchange (ETDEWEB)

Sternberg, R. [Department of Earth and Environmental Studies, Montclair State University, 1 Normal Ave, Montclair, NJ 07043-1624 (United States)

2010-02-15

Hydropower is a well established electricity system on the global scene. Global electricity needs by far exceed the amount of electricity that hydrosystems can provide to meet global electricity needs. Much of the world's hydropower remains to be brought into production. Improved technology, better calibrated environmental parameters for large projects have become the norm in the past 15 years. How and why does hydropower retain a prominent role in electricity production? How and why does hydropower find social acceptance in diverse social systems? How does hydropower project planning address issues beyond electricity generation? How does the systems approach to hydropower installations further analysis of comparative energy sources powering electricity systems? Attention to the environmental impact of hydropower facilities forms an integral part of systems analysis. Similarly, the technical, political and economic variables call for balanced analysis to identify the viability status of hydro projects. Economic competition among energy systems requires in context assessments as these shape decision making in planning of hydropower systems. Moreover, technological change has to be given a time frame during which the sector advances in productivity and share in expanding electricity generation. The low production costs per kWh assure hydropower at this juncture, 2009, a very viable future. (author)

Hydropower Modeling Challenges

Energy Technology Data Exchange (ETDEWEB)

Stoll, Brady [National Renewable Energy Lab. (NREL), Golden, CO (United States); Andrade, Juan [National Renewable Energy Lab. (NREL), Golden, CO (United States); Cohen, Stuart [National Renewable Energy Lab. (NREL), Golden, CO (United States); Brinkman, Greg [National Renewable Energy Lab. (NREL), Golden, CO (United States); Brancucci Martinez-Anido, Carlo [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2017-04-19

Hydropower facilities are important assets for the electric power sector and represent a key source of flexibility for electric grids with large amounts of variable generation. As variable renewable generation sources expand, understanding the capabilities and limitations of the flexibility from hydropower resources is important for grid planning. Appropriately modeling these resources, however, is difficult because of the wide variety of constraints these plants face that other generators do not. These constraints can be broadly categorized as environmental, operational, and regulatory. This report highlights several key issues involving incorporating these constraints when modeling hydropower operations in terms of production cost and capacity expansion. Many of these challenges involve a lack of data to adequately represent the constraints or issues of model complexity and run time. We present several potential methods for improving the accuracy of hydropower representation in these models to allow for a better understanding of hydropower's capabilities.

Intraarterial CT Angiography Using Ultra Low Volume of Iodine Contrast – Own Experiences

International Nuclear Information System (INIS)

Garcarek, Jerzy; Kurcz, Jacek; Guziński, Maciej; Banasik, Mirosław; Miś, Marcin; Gołębiowski, Tomasz

2015-01-01

High volume of intravenous contrast in CT-angiography may result in contrast-induced nephropathy. Intraarterial ultra-low volume of contrast medium results in its satisfactory blood concentration with potentially good image quality. The first main purpose was to assess the influence of the method on function of transplanted kidney in patients with impaired graft function. The second main purpose of the study was to evaluate the usefulness of this method for detection of gastrointestinal and head-and-neck haemorrhages. Between 2010 and 2013 intraarterial CT-angiography was performed in 56 patients, including 28 with chronic kidney disease (CKD). There were three main subgroups: 18 patients after kidney transplantation, 10 patients with gastrointestinal hemorrhage, 8 patients with head-and-neck hemorrhage. Contralateral or ipsilateral inguinal arterial approach was performed. The 4-French vascular sheaths and 4F-catheters were introduced under fluoroscopy. Intraarterial CT was performed using 64-slice scanner. The scanning protocol was as follows: slice thickness 0.625 mm, pitch 1.3, gantry rotation 0.6 sec., scanning delay 1–2 sec. The extent of the study was established on the basis of scout image. In patients with CKD 6–8 mL of Iodixanol (320 mg/mL) diluted with saline to 18–24 mL was administered at a speed of 4–5 mL/s. Vasculature was properly visualized in all patients. In patients with impaired renal function creatinine/eGFR levels remained stable in all but one case. Traditional arteriography failed and CT-angiography demonstrated the site of bleeding in 3 of 10 patients with symptoms of gastrointestinal bleeding (30%). In 8 patients with head-and-neck bleeding CT-angiography did not prove beneficial when compared to traditional arteriography. 1. Ultra-low contrast intraarterial CT-angiography does not deteriorate the function of transplanted kidneys in patients with impaired graft function. 2. 3D reconstructions allow for excellent visualization of

Ultra low-power integrated circuit design for wireless neural interfaces

CERN Document Server

Holleman, Jeremy; Otis, Brian

2014-01-01

Presenting results from real prototype systems, this volume provides an overview of ultra low-power integrated circuits and systems for neural signal processing and wireless communication. Topics include analog, radio, and signal processing theory and design for ultra low-power circuits.

Endometrial safety of ultra-low-dose estradiol vaginal tablets

DEFF Research Database (Denmark)

Simon, James; Nachtigall, Lila; Ulrich, Lian G

2010-01-01

To evaluate the endometrial hyperplasia and carcinoma rate after 52-week treatment with ultra-low-dose 10-microgram 17ß-estradiol vaginal tablets in postmenopausal women with vaginal atrophy.......To evaluate the endometrial hyperplasia and carcinoma rate after 52-week treatment with ultra-low-dose 10-microgram 17ß-estradiol vaginal tablets in postmenopausal women with vaginal atrophy....

Endometrial safety of ultra-low-dose estradiol vaginal tablets

DEFF Research Database (Denmark)

Simon, James; Nachtigall, Lila; Ulrich, Lian G

2010-01-01

To evaluate the endometrial hyperplasia and carcinoma rate after 52-week treatment with ultra-low-dose 10-microgram 17β-estradiol vaginal tablets in postmenopausal women with vaginal atrophy.......To evaluate the endometrial hyperplasia and carcinoma rate after 52-week treatment with ultra-low-dose 10-microgram 17β-estradiol vaginal tablets in postmenopausal women with vaginal atrophy....

Small Hydropower - The comeback of small hydropower stations

International Nuclear Information System (INIS)

Niederhaeusern, A.

2008-01-01

This issue of the 'Erneuerbare Energien' (renewable energies) magazine published by the Swiss Solar Energy Society takes a look at small hydropower projects in Switzerland. In a number of interviews and articles, various topics concerning small hydropower are dealt with. First of all, an interview with Bruno Guggisberg, previously responsible for small hydro at the Swiss Federal Office of Energy, examines the potential of small hydro and the various political, technical and economic influences on such projects. Further articles provide an overview of the various types of small hydro schemes, including power generation using height differences in drinking-water and wastewater installations. As far as the components of small hydro schemes are concerned, various types of turbines and further system components that are needed are examined. A further article takes a look at the small hydro market and the market players involved. Ecological aspects and research activities are discussed in further articles. In a second interview with Martin Boelli, presently responsible for small hydropower at the Swiss Federal Office of Energy, the unused potential for the use of hydropower in Switzerland is discussed. Examples of small-scale hydro schemes are examined and the support offered by the Small Hydropower Program is discussed. Finally the question is asked, if the small hydro market in Switzerland is overheated as a result of promotion schemes such as cost-covering remuneration for electricity from renewable energy sources.

Small hydropower plants in the region of Mariovo (Macedonia)

International Nuclear Information System (INIS)

Panovski, Sotir; Anastasov, Ljupcho

2003-01-01

In this paper the results of an initial Pre-feasibility study within the framework of the PHARE Programme for Cross Border Cooperation between Republic of Macedonia and Republic of Greece. In this study we have looked at the existing research originating from three sources. The Strategies for Economic Development of Republic of Macedonia, the Development Plans of the Electric Power Company of Macedonia as well as the existing technical documentation and studies on a level of idea projects for specific location for small hydropower plants in Mariovo region. Furthermore, analysis and evaluation of this documentation is included. Research done in this region has produced evidence of numerous potential locations for small hydropower plants (total of 46) generating power between 58 kW and 4900 kW, discharging between 0,082 m 3 /s and 30 m 3 /s with a head between 6 m and 208 m for which we have detailed data. Furthermore, in the paper we pay attention to the enormous and so far unrealised hydro energetic power which could be utilised by constructing small hydropower plants in Republic of Macedonia. specifically in the Mariovo region. (Original)

Natural gas price uncertainty and the cost-effectiveness of hedging against low hydropower revenues caused by drought

Science.gov (United States)

Kern, Jordan D.; Characklis, Gregory W.; Foster, Benjamin T.

2015-04-01

Prolonged periods of low reservoir inflows (droughts) significantly reduce a hydropower producer's ability to generate both electricity and revenues. Given the capital intensive nature of the electric power industry, this can impact hydropower producers' ability to pay down outstanding debt, leading to credit rating downgrades, higher interests rates on new debt, and ultimately, greater infrastructure costs. One potential tool for reducing the financial exposure of hydropower producers to drought is hydrologic index insurance, in particular, contracts structured to payout when streamflows drop below a specified level. An ongoing challenge in developing this type of insurance, however, is minimizing contracts' "basis risk," that is, the degree to which contract payouts deviate in timing and/or amount from actual damages experienced by policyholders. In this paper, we show that consideration of year-to-year changes in the value of hydropower (i.e., the cost of replacing it with an alternative energy source during droughts) is critical to reducing contract basis risk. In particular, we find that volatility in the price of natural gas, a key driver of peak electricity prices, can significantly degrade the performance of index insurance unless contracts are designed to explicitly consider natural gas prices when determining payouts. Results show that a combined index whose value is derived from both seasonal streamflows and the spot price of natural gas yields contracts that exhibit both lower basis risk and greater effectiveness in terms of reducing financial exposure.

Renewable Energy Essentials: Hydropower

Energy Technology Data Exchange (ETDEWEB)

NONE

2010-07-01

Hydropower is currently the most common form of renewable energy and plays an important part in global power generation. Worldwide hydropower produced 3 288 TWh, just over 16% of global electricity production in 2008, and the overall technical potential for hydropower is estimated to be more than 16 400 TWh/yr.

Feasibility determination of low head hydroelectric power development at existing sites: Mousam River Project

Energy Technology Data Exchange (ETDEWEB)

1979-06-01

The technical and economic feasibility of low head hydroelectric power development at existing sites along the Mousam River in southeastern Maine was studied. The following areas were investigated: determination of available energy; development of restoration concepts; environmental studies; historical and archeological studies; assessment of civil construction requirements; geotechnical and geologic assessment of existing dams; assessment of turbine alternatives; assessment of generator and utility interface alternatives; economic analysis; and restoration concept evaluation and selection. The results of the hydropower evaluation showed that: of the seven sites evaluated, only four can be considered economically feasible for refurbishment at this time; the use of used and/or rebuilt equipment is more economically attractive than new equipment; the cost of equipment at each site was of the same order as the cost of the dam reconstruction; and the cost of fuel prices will be the determining feature of whether the sites should be reconstructed.

Design of ultra-low power impulse radios

CERN Document Server

Apsel, Alyssa; Dokania, Rajeev

2014-01-01

This book covers the fundamental principles behind the design of ultra-low power radios and how they can form networks to facilitate a variety of applications within healthcare and environmental monitoring, since they may operate for years off a small battery or even harvest energy from the environment. These radios are distinct from conventional radios in that they must operate with very constrained resources and low overhead.  This book provides a thorough discussion of the challenges associated with designing radios with such constrained resources, as well as fundamental design concepts and practical approaches to implementing working designs.  Coverage includes integrated circuit design, timing and control considerations, fundamental theory behind low power and time domain operation, and network/communication protocol considerations.   • Enables detailed understanding of the design space for ultra-low power radio; • Provides detailed discussion and examples of the design of a practical low power ...

Hydropower externalities: A meta-analysis

International Nuclear Information System (INIS)

Mattmann, Matteo; Logar, Ivana; Brouwer, Roy

2016-01-01

This paper presents a meta-analysis of existing research related to the economic valuation of the external effects of hydropower. A database consisting of 81 observations derived from 29 studies valuing the non-market impacts of hydropower electricity generation is constructed with the main aim to quantify and explain the economic values for positive and negative hydropower externalities. Different meta-regression model specifications are used to test the robustness of significant determinants of non-market values, including different types of hydropower impacts. The explanatory and predictive power of the estimated models is relatively high. Whilst controlling for sample and study characteristics, we find significant evidence for public aversion towards deteriorations of landscape, vegetation and wildlife caused by hydropower projects. There is however only weak evidence of willingness to pay for mitigating these effects. The main positive externality of hydropower generation, the avoidance of greenhouse gas emission, positively influences welfare estimates when combined with the share of hydropower in national energy production. Sensitivity to scope is detected, but not linked to specific externalities or non-market valuation methods. - Highlights: • A global meta-analysis of valuation studies of hydropower externalities is presented. • Positive and negative externalities are distinguished. • Welfare losses due to environmental deteriorations outweigh gains of GHG reductions. • There is only weak evidence of public WTP for mitigating negative externalities. • The non-market values of hydropower externalities are sensitive to scope.

Economic implications of climate-driven trends in global hydropower generation

Science.gov (United States)

Turner, S. W. D.; Galelli, S.; Hejazi, M. I.; Clarke, L.; Edmonds, J.; Kim, S. H.

2017-12-01

Recent progress in global scale hydrological and dam modeling has allowed for the study of climate change impacts on global hydropower production. Here we explore how these impacts could affect the composition of global electricity supply, and what those changes could mean for power sector emissions and investment needs in the 21st century. Regional hydropower projections are developed for two emissions scenarios by forcing a coupled global hydrological and dam model (1593 major hydropower dams; 54% global installed capacity) with downscaled, bias-corrected climate realizations derived from sixteen General Circulation Models (GCMs). To incorporate possible non-linearity in hydropower response to climate change, dam simulations incorporate plant specifications (e.g., maximum turbine flow), reservoir storage dynamics, reservoir bathymetry, evaporation losses and bespoke, site specific operations. Consequent impacts on regional and global-level electricity generation and associated emissions and investment costs are examined using the Global Change Assessment Model (GCAM). We show that changes in hydropower generation resulting from climate change can shift power demands onto and away from carbon intensive technologies, resulting in significant impacts on CO2 emissions for several regions. Many of these countries are also highly vulnerable to investment impacts (costs of new electricity generating facilities to make up for shortfalls in hydro), which in some cases amount to tens of billions of dollars by 2100. The Balkans region—typified by weak economies in a drying region that relies heavily on hydropower—emerges as the most vulnerable. Reduced impacts of climate change on hydropower production under a low emissions scenario coincide with increased costs of marginal power generating capacity (low emissions requires greater uptake of clean generating technologies, which are more expensive). This means impacts on power sector investment costs are similar for high

Hydropower Baseline Cost Modeling, Version 2

Energy Technology Data Exchange (ETDEWEB)

O' Connor, Patrick W. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2015-09-01

Recent resource assessments conducted by the United States Department of Energy have identified significant opportunities for expanding hydropower generation through the addition of power to non-powered dams and on undeveloped stream-reaches. Additional interest exists in the powering of existing water resource infrastructure such as conduits and canals, upgrading and expanding existing hydropower facilities, and the construction new pumped storage hydropower. Understanding the potential future role of these hydropower resources in the nation’s energy system requires an assessment of the environmental and techno-economic issues associated with expanding hydropower generation. To facilitate these assessments, this report seeks to fill the current gaps in publically available hydropower cost estimating tools that can support the national-scale evaluation of hydropower resources.

78 FR 14528 - Mayo Hydropower, LLC, Avalon Hydropower, LLC; Notice of Application for Transfer of License, and...

Science.gov (United States)

2013-03-06

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Project No. 11169-029] Mayo Hydropower, LLC, Avalon Hydropower, LLC; Notice of Application for Transfer of License, and Soliciting Comments and Motions To Intervene On November 20, 2012, Mayo Hydropower, LLC (transferor) and Avalon Hydropower...

2014 Hydropower Market Report

Energy Technology Data Exchange (ETDEWEB)

Rocío Uría-Martínez, Patrick W. O’Connor, Megan M. Johnson

2015-04-30

The U.S. hydropower fleet has been providing clean, reliable power for more than a hundred years. However, no systematic documentation exists of the U.S. fleet and the trends influencing it in recent years. This first-ever Hydropower Market Report seeks to fill this gap and provide industry and policy makers with a quantitative baseline on the distribution, capabilities, and status of hydropower in the United States.

Quadrennial Technology Review 2015: Technology Assessments--Hydropower

Energy Technology Data Exchange (ETDEWEB)

Sam Baldwin, Gilbert Bindewald, Austin Brown, Charles Chen, Kerry Cheung, Corrie Clark, Joe Cresko,

2015-10-07

Hydropower has provided reliable and flexible base and peaking power generation in the United States for more than a century, contributing on average 10.5% of cumulative U.S. power sector net generation over the past six and one-half decades (1949–2013). It is the nation’s largest source of renewable electricity, with 79 GW of generating assets and 22 GW of pumped-storage assets in service, with hydropower providing half of all U.S. renewable power-sector generation (50% in 2014). In addition to this capacity, the U.S. Department of Energy (DOE) has identified greater than 80 GW of new hydropower resource potential: at least 5 GW from rehabilitation and expansion of existing generating assets, up to 12 GW of potential at existing dams without power facilities, and over 60 GW of potential low-impact new development (LIND) in undeveloped stream reaches. However, despite this growth potential, hydropower capacity and production growth have stalled in recent years, with existing assets even experiencing decreases in capacity and production from lack of sustaining investments in infrastructure and increasing constraints on water use.

Note: Ultra-low birefringence dodecagonal vacuum glass cell

Energy Technology Data Exchange (ETDEWEB)

Brakhane, Stefan, E-mail: brakhane@iap.uni-bonn.de; Alt, Wolfgang; Meschede, Dieter; Robens, Carsten; Moon, Geol; Alberti, Andrea [Institut für Angewandte Physik, Universität Bonn, Wegelerstr. 8, D-53115 Bonn (Germany)

2015-12-15

We report on an ultra-low birefringence dodecagonal glass cell for ultra-high vacuum applications. The epoxy-bonded trapezoidal windows of the cell are made of SF57 glass, which exhibits a very low stress-induced birefringence. We characterize the birefringence Δn of each window with the cell under vacuum conditions, obtaining values around 10{sup −8}. After baking the cell at 150 °C, we reach a pressure below 10{sup −10} mbar. In addition, each window is antireflection coated on both sides, which is highly desirable for quantum optics experiments and precision measurements.

Climate change impacts and greenhouse gas mitigation effects on U.S. hydropower generation

International Nuclear Information System (INIS)

Boehlert, Brent; Strzepek, Kenneth M.; Gebretsadik, Yohannes; Swanson, Richard; McCluskey, Alyssa; Neumann, James E.; McFarland, James; Martinich, Jeremy

2016-01-01

Highlights: • Analyze contiguous U.S. hydropower generation under various emissions scenarios. • Employ systems model that allocates water to competing uses in 2119 river basins. • Average U.S. generation increases under climate change, but falls under low flows. • Mitigation benefits are $2-$4 billion/year due to high values of carbon-free energy. - Abstract: Climate change will have potentially significant effects on hydropower generation due to changes in the magnitude and seasonality of river runoff and increases in reservoir evaporation. These physical impacts will in turn have economic consequences through both producer revenues and consumer expenditures. We analyze the physical and economic effects of changes in hydropower generation for the contiguous U.S. in futures with and without global-scale greenhouse gas (GHG) mitigation, and across patterns from 18 General Circulation Models. Using a monthly water resources systems model of 2119 river basins that routes simulated river runoff through reservoirs, and allocates water to potentially conflicting and climate dependent demands, we provide a first-order estimate of the impacts of various projected emissions outcomes on hydropower generation, and monetize these impacts using outputs from an electric sector planning model for over 500 of the largest U.S. hydropower facilities. We find that, due to generally increasing river runoff under higher emissions scenarios in the Pacific Northwest, climate change tends to increase overall hydropower generation in the contiguous U.S. During low flow months, generation tends to fall with increasing emissions, potentially threatening the estimated low flow, firm energy from hydropower. Although global GHG mitigation slows the growth in hydropower generation, the higher value placed on carbon-free hydropower leads to annual economic benefits ranging from $1.8 billion to $4.3 billion. The present value of these benefits to the U.S. from global greenhouse gas

Assessment of the economic impact of environmental constraints on short-term hydropower plant operation

International Nuclear Information System (INIS)

Perez-Diaz, Juan I.; Wilhelmi, Jose R.

2010-01-01

Environmental constraints imposed on hydropower plant operation are usually given in the form of minimum environmental flows and, in some cases, in the form of maximum and minimum rates of change of flows, or ramping rates. Environmental constraints reduce the amount of water available to produce electricity and limit the contribution of peak hydropower plants to adapting the power supply to the demand and to providing certain ancillary services to the electrical grid, such as spinning reserve or load-frequency control. The objective of this paper is to assess the economic impact of environmental constraints on short-term hydropower plant operation. For that purpose, a revenue-driven daily optimization model based on mixed integer linear programming is used. The model considers the head variation and its influence on the units' efficiency, as well as the option of starting-up or shutting-down the plant at any hour of the day, should it be advantageous, while releasing the environmental flow through the bottom outlets. In order to illustrate the applicability of the methodology, it is applied in a real hydropower plant under different operating conditions and environmental constraints. (author)

Assessment of the economic impact of environmental constraints on short-term hydropower plant operation

Energy Technology Data Exchange (ETDEWEB)

Perez-Diaz, Juan I.; Wilhelmi, Jose R. [Department of Hydraulic and Energy Engineering, Technical University of Madrid (UPM), c/Profesor Aranguren s/n, 28040 Madrid (Spain)

2010-12-15

Environmental constraints imposed on hydropower plant operation are usually given in the form of minimum environmental flows and, in some cases, in the form of maximum and minimum rates of change of flows, or ramping rates. Environmental constraints reduce the amount of water available to produce electricity and limit the contribution of peak hydropower plants to adapting the power supply to the demand and to providing certain ancillary services to the electrical grid, such as spinning reserve or load-frequency control. The objective of this paper is to assess the economic impact of environmental constraints on short-term hydropower plant operation. For that purpose, a revenue-driven daily optimization model based on mixed integer linear programming is used. The model considers the head variation and its influence on the units' efficiency, as well as the option of starting-up or shutting-down the plant at any hour of the day, should it be advantageous, while releasing the environmental flow through the bottom outlets. In order to illustrate the applicability of the methodology, it is applied in a real hydropower plant under different operating conditions and environmental constraints. (author)

Assessing Climate Change Impacts on Global Hydropower

Directory of Open Access Journals (Sweden)

Aanund Killingtveit

2012-02-01

Full Text Available Currently, hydropower accounts for close to 16% of the world’s total power supply and is the world’s most dominant (86% source of renewable electrical energy. The key resource for hydropower generation is runoff, which is dependent on precipitation. The future global climate is uncertain and thus poses some risk for the hydropower generation sector. The crucial question and challenge then is what will be the impact of climate change on global hydropower generation and what are the resulting regional variations in hydropower generation potential? This paper is a study that aims to evaluate the changes in global hydropower generation resulting from predicted changes in climate. The study uses an ensemble of simulations of regional patterns of changes in runoff, computed from global circulation models (GCM simulations with 12 different models. Based on these runoff changes, hydropower generation is estimated by relating the runoff changes to hydropower generation potential through geographical information system (GIS, based on 2005 hydropower generation. Hydropower data obtained from EIA (energy generation, national sites, FAO (water resources and UNEP were used in the analysis. The countries/states were used as computational units to reduce the complexities of the analysis. The results indicate that there are large variations of changes (increases/decreases in hydropower generation across regions and even within regions. Globally, hydropower generation is predicted to change very little by the year 2050 for the hydropower system in operation today. This change amounts to an increase of less than 1% of the current (2005 generation level although it is necessary to carry out basin level detailed assessment for local impacts which may differ from the country based values. There are many regions where runoff and hydropower generation will increase due to increasing precipitation, but also many regions where there will be a decrease. Based on this

Low-Weight, Durable, and Low-Cost Metal Rubber Sensor System for Ultra Long Duration Scientific Balloons, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — NanoSonic proposes to develop an innovative, low-cost, ultra low mass density, and non-intrusive sensor system for ultra long duration balloons (ULDB) that will...

Hydropower and Sustainable Development: A Journey

Energy Technology Data Exchange (ETDEWEB)

Schumann, Kristin; Saili, Lau; Taylor, Richard; Abdel-Malek, Refaat

2010-09-15

Hydropower produces 16% of our electricity; it is one of the world's major renewable energy resources. It is playing an important role in enabling communities around the world to meet their power and water needs. The pace of hydropower growth has been rapid but sometimes with little guidance to ensure development is based on sustainability principles. Some of the most promising initiatives to fill the void, such as the Hydropower Sustainability Assessment Protocol, have been driven by the hydropower sector itself. Efforts focus on carrying forward this momentum to obtain a tool for hydropower sustainability agreed across sectors and stakeholders.

Ultra-low temperature curable nano-silver conductive adhesive for piezoelectric composite material

Science.gov (United States)

Yan, Chao; Liao, Qingwei; Zhou, Xingli; Wang, Likun; Zhong, Chao; Zhang, Di

2018-01-01

Limited by the low thermal resistance of composite material, ultra-low temperature curable conductive silver adhesive with curing temperature less than 100 °C needed urgently for the surface conduction treatment of piezoelectric composite material. An ultra-low temperature curable nano-silver conductive adhesive with high adhesion strength for the applications of piezoelectric composite material was investigated. The crystal structure of cured adhesive, SEM/EDS analysis, thermal analysis, adhesive properties and conductive properties of different content of nano-silver filler or micron-silver doping samples were studied. The results show that with 60 wt.% nano-silver filler the ultra-low temperature curable conductive silver adhesive had the relatively good conductivity as volume resistivity of 2.37 × 10-4 Ω cm, and good adhesion strength of 5.13 MPa. Minor micron-doping (below 15 wt.%) could improve conductivity, but would decrease other properties. The ultra-low temperature curable nano-silver conductive adhesive could successfully applied to piezoelectric composite material.

Modeling and dynamic behaviour of hydropower plants

CERN Document Server

Kishor, Nand

2017-01-01

This book presents a systematic approach to mathematical modeling of different configurations of hydropower plants over four sections - modeling and simulation approaches; control of hydropower plants; operation and scheduling of hydropower plants, including pumped storage; and special features of small hydropower plants.

Hydropower Vision: Full Report

Energy Technology Data Exchange (ETDEWEB)

None, None

2016-07-01

Hydropower has provided clean, affordable, reliable, and renewable electricity in the United States for more than a century. Building on hydropower’s historical significance, and to inform the continued technical evolution, energy market value, and environmental performance of the industry, the U.S. Department of Energy’s (DOE’s) Wind and Water Power Technologies Office has led a first-of-its-kind comprehensive analysis focused on a set of potential pathways for the environmentally sustainable expansion of hydropower (hydropower generation and pumped storage) in the United States.

Small hydropower spot prediction using SWAT and a diversion algorithm, case study: Upper Citarum Basin

Science.gov (United States)

Kardhana, Hadi; Arya, Doni Khaira; Hadihardaja, Iwan K.; Widyaningtyas, Riawan, Edi; Lubis, Atika

2017-11-01

Small-Scale Hydropower (SHP) had been important electric energy power source in Indonesia. Indonesia is vast countries, consists of more than 17.000 islands. It has large fresh water resource about 3 m of rainfall and 2 m of runoff. Much of its topography is mountainous, remote but abundant with potential energy. Millions of people do not have sufficient access to electricity, some live in the remote places. Recently, SHP development was encouraged for energy supply of the places. Development of global hydrology data provides opportunity to predict distribution of hydropower potential. In this paper, we demonstrate run-of-river type SHP spot prediction tool using SWAT and a river diversion algorithm. The use of Soil and Water Assessment Tool (SWAT) with input of CFSR (Climate Forecast System Re-analysis) of 10 years period had been implemented to predict spatially distributed flow cumulative distribution function (CDF). A simple algorithm to maximize potential head of a location by a river diversion expressing head race and penstock had been applied. Firm flow and power of the SHP were estimated from the CDF and the algorithm. The tool applied to Upper Citarum River Basin and three out of four existing hydropower locations had been well predicted. The result implies that this tool is able to support acceleration of SHP development at earlier phase.

Path Transmissibility Analysis Considering Two Types of Correlations in Hydropower Stations

Directory of Open Access Journals (Sweden)

Baoping Zhi

2013-01-01

Full Text Available A new vibration model is built by introducing the head-cover vibration transfer path based on a previous analysis of the vertical vibration model for hydropower station units and powerhouses. This research focuses on disturbance- and parameter-related transfer paths in a practical situation. In a complex situation, the application of the stochastic perturbation method is expanded using an algebra synthesis method the Hadamard product, and theoretical analyses, and numerical simulations of transfer paths in the new vibration model are carried out through the expanded perturbation method. The path transfer force, the path transmissibility, and the path disturbance ranges in the frequency domain are provided. The results indicate that the methods proposed in this study can efficiently reduce the disturbance range and can accurately analyze the transfer paths of hydraulic-source vertical vibration in hydropower stations.

Biodiesel as a lubricity additive for ultra low sulfur diesel

Directory of Open Access Journals (Sweden)

Subongkoj Topaiboul1 and 2,*

2010-05-01

Full Text Available With the worldwide trend to reduce emission from diesel engines, ultra low sulfur diesel has been introduced with thesulfur concentration of less than 10 ppm. Unfortunately, the desulfurization process inevitably reduces the lubricity of dieselfuel significantly. Alternatively, biodiesel, with almost zero sulfur content, has been added to enhance lubricity in an ultralow sulfur diesel. This work has evaluated the effectiveness of the biodiesel amount, sourced from palm and jatropha oil,and origin in ultra low sulfur diesel locally available in the market. Wear scar from a high-frequency reciprocating rig isbenchmarked to the standard value (460 m of diesel fuel lubricity. It was found that very small amount (less than 1% ofbiodiesel from either source significantly improves the lubricity in ultra low sulfur diesel, and the biodiesel from jatropha oilis a superior lubricity enhancer.

Wear resistant performance of highly cross-linked and annealed ultra-high molecular weight polyethylene against ceramic heads in total hip arthroplasty.

Science.gov (United States)

Sato, Taishi; Nakashima, Yasuharu; Akiyama, Mio; Yamamoto, Takuaki; Mawatari, Taro; Itokawa, Takashi; Ohishi, Masanobu; Motomura, Goro; Hirata, Masanobu; Iwamoto, Yukihide

2012-12-01

The purpose of this study was to examine the effects of ceramic femoral head material, size, and implantation periods on the wear of annealed, cross-linked ultra-high molecular weight polyethylene (UHMWPE) (XLPE) in total hip arthroplasty compared to non-cross-linked conventional UHMWPE (CPE). XLPE was fabricated by cross-linking with 60 kGy irradiation and annealing. Femoral heads made from zirconia and alumina ceramics and cobalt-chrome (CoCr) of 22 or 26 mm diameter were used. In this retrospective cohort study, the femoral head penetration into the cup was measured digitally on radiographs of 367 hips with XLPE and 64 hips with CPE. The average follow-up periods were 6.3 and 11.9 years, respectively. Both XLPE creep and wear rates were significantly lower than those of CPE (0.19 mm vs. 0.44 mm, 0.0001 mm/year vs. 0.09 mm/year, respectively). Zirconia displayed increased wear rates compared to alumina in CPE; however, there was no difference among head materials in XLPE (0.0008, 0.00007, and -0.009 mm/year for zirconia, alumina, and CoCr, respectively). Neither head size or implantation period impacted XLPE wear. In contrast to CPE, XLPE displayed low wear rates surpassing the effects of varying femoral head material, size, implantation period, and patient demographics. Further follow-up is required to determine the long-term clinical performance of the annealed XLPE. Copyright © 2012 Orthopaedic Research Society.

An ultra-low power output capacitor-less low-dropout regulator with slew-rate-enhanced circuit

Science.gov (United States)

Cheng, Xin; Zhang, Yu; Xie, Guangjun; Yang, Yizhong; Zhang, Zhang

2018-03-01

An ultra-low power output-capacitorless low-dropout (LDO) regulator with a slew-rate-enhanced (SRE) circuit is introduced. The increased slew rate is achieved by sensing the transient output voltage of the LDO and then charging (or discharging) the gate capacitor quickly. In addition, a buffer with ultra-low output impedance is presented to improve line and load regulations. This design is fabricated by SMIC 0.18 μm CMOS technology. Experimental results show that, the proposed LDO regulator only consumes an ultra-low quiescent current of 1.2 μA. The output current range is from 10 μA to 200 mA and the corresponding variation of output voltage is less than 40 mV. Moreover, the measured line regulation and load regulation are 15.38 mV/V and 0.4 mV/mA respectively. Project supported by the National Natural Science Foundation of China (Nos. 61401137, 61404043, 61674049).

Along-the-net reconstruction of hydropower potential with consideration of anthropic alterations

Directory of Open Access Journals (Sweden)

A. Masoero

2014-09-01

Full Text Available Even in regions with mature hydropower development, requirements for stable renewable power sources suggest revision of plans of exploitation of water resources, while taking care of the environmental regulations. Mean Annual Flow (MAF is a key parameter when trying to represent water availability for hydropower purposes. MAF is usually determined in ungauged basins by means of regional statistical analysis. For this study a regional estimation method consistent along-the-river network has been developed for MAF estimation; the method uses a multi-regressive approach based on geomorphoclimatic descriptors, and it is applied on 100 gauged basins located in NW Italy. The method has been designed to keep the estimates of mean annual flow congruent at the confluences, by considering only raster-summable explanatory variables. Also, the influence of human alterations in the regional analysis of MAF has been studied: impact due to the presence of existing hydropower plants has been taken into account, restoring the "natural" value of runoff through analytical corrections. To exemplify the representation of the assessment of residual hydropower potential, the model has been applied extensively to two specific mountain watersheds by mapping the estimated mean flow for the basins draining into each pixel of a the DEM-derived river network. Spatial algorithms were developed using the OpenSource Software GRASS GIS and PostgreSQL/PostGIS. Spatial representation of the hydropower potential was obtained using different mean flow vs hydraulic-head relations for each pixel. Final potential indices have been represented and mapped through the Google Earth platform, providing a complete and interactive picture of the available potential, useful for planning and regulation purposes.

Regulatory approaches for addressing dissolved oxygen concerns at hydropower facilities

Energy Technology Data Exchange (ETDEWEB)

Peterson, Mark J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Cada, Glenn F. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Sale, Michael J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Eddlemon, Gerald K. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2003-03-01

Low dissolved oxygen (DO) concentrations are a common water quality problem downstream of hydropower facilities. At some facilities, structural improvements (e.g. installation of weir dams or aerating turbines) or operational changes (e.g., spilling water over the dam) can be made to improve DO levels. In other cases, structural and operational approaches are too costly for the project to implement or are likely to be of limited effectiveness. Despite improvements in overall water quality below dams in recent years, many hydropower projects are unable to meet state water quality standards for DO. Regulatory agencies in the U.S. are considering or implementing dramatic changes in their approach to protecting the quality of the Nation’s waters. New policies and initiatives have emphasized flexibility, increased collaboration and shared responsibility among all parties, and market-based, economic incentives. The use of new regulatory approaches may now be a viable option for addressing the DO problem at some hydropower facilities. This report summarizes some of the regulatory-related options available to hydropower projects, including negotiation of site-specific water quality criteria, use of biological monitoring, watershed-based strategies for the management of water quality, and watershed-based trading. Key decision points center on the health of the local biological communities and whether there are contributing impacts (i.e., other sources of low DO effluents) in the watershed. If the biological communities downstream of the hydropower project are healthy, negotiation for site-specific water quality standards or biocriteria (discharge performance criteria based on characteristics of the aquatic biota) might be pursued. If there are other effluent dischargers in the watershed that contribute to low DO problems, watershed-scale strategies and effluent trading may be effective. This report examines the value of regulatory approaches by reviewing their use in

Environmental impact of hydropower systems

International Nuclear Information System (INIS)

Malai, Marius

1996-01-01

The installed hydropower potential of Romania is evaluated to 15,700 MW and 42 billion MWh/year power generation. Only 39% of this potential are currently being utilized. In this note, the impact of Somes-Tarnita and Mariselu-Cluj hydropower systems on the environment is presented. Also, the socio-economic effects on the local communities are considered. These two hydropower systems supply a total electric power of 470 GWh/year

Ultra low power full adder topologies

DEFF Research Database (Denmark)

Moradi, Farshad; Wisland, Dag T.; Mahmoodi, Hamid

In this paper several low power full adder topologies are presented. The main idea of these circuits is based on the sense energy recovery full adder (SERF) design and the GDI (gate diffusion input) technique. These subthreshold circuits are employed for ultra low power applications. While the pr...... the proposed circuits have some area overhead that is negligible, they have at least 62% less power dissipation when compared with existing designs. In this paper, 65 nm standard models are used for simulations....

Hydropower annual report 2003

Energy Technology Data Exchange (ETDEWEB)

Cada, Glenn F. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Carlson, Thomas J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Dauble, Dennis D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hunt, Richard T. [Idaho National Lab. (INL), Idaho Falls, ID (United States). Idaho National Engineering Lab. (INEL); Sale, Michael J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Sommers, Garold L. [Idaho National Lab. (INL), Idaho Falls, ID (United States). Idaho National Engineering Lab. (INEL)

2004-02-01

This report describes hydropower activities supported by the U.S. Department of Energy (DOE) Wind and Hydropower Program during Fiscal Year 2003 (October 1, 2002 to September 30, 2003). Background on the program, FY03 accomplishments, and future plans are presented in the following sections.

Feasibility study of VLH hydro turbine installation at Nam Pung hydropower plant, Thailand

Directory of Open Access Journals (Sweden)

Weerapon Nuantong

2016-10-01

Full Text Available The aim of this research was to study the feasibility of installing a Very Low Head (VLH hydro turbine at downstream of the Nam Pung hydropower plant by increasing the potential of renewable energy sources for the Electricity Generating Authority of Thailand (EGAT. Due to the constraints of the local site, the water head level was limited to less than 2 meters and the flow rate to below 5 m3/ s. The hydro turbine selected was an axial flow turbine with performance of 86.4%. The outcome of the power output was 84.61 kW. Investment analysis was subsequently applied to estimate feasibility of the project using engineering economics. The analyses of results have shown that the project is worthwhile in terms of an investment decision. The payback period of actual price was 0.83 and 0.88 years and general price case of 3.68 and 4.04 years, along with an interest rate of 6.75% and 12.625% respectively. Projected project lifespan is 25 years.

U.S. Hydropower Resource Assessment - California

Energy Technology Data Exchange (ETDEWEB)

A. M. Conner; B. N. Rinehart; J. E. Francfort

1998-10-01

The U.S. Department of Energy is developing an estimate of the underdeveloped hydropower potential in the United States. For this purpose, the Idaho National Engineering and Environmental Laboratory developed a computer model called Hydropower Evaluation Software (HES). HES measures the undeveloped hydropower resources available in the United States, using uniform criteria for measurement. The software was developed and tested using hydropower information and data provided by the Southwestern Power Administration. It is a menu-driven program that allows the personal computer user to assign environmental attributes to potential hydropower sites, calculate development suitability factors for each site based on the environmental attributes present, and generate reports based on these suitability factors. This report describes the resource assessment results for the State of California.

US Hydropower Resource Assessment for Massachusetts

Energy Technology Data Exchange (ETDEWEB)

Francfort, J.E.; Rinehart, B.N.

1995-07-01

The Department of Energy is developing an estimate of the undeveloped hydropower potential in the United States. The Hydropower Evaluation Software (HES) is a computer model that was developed by the Idaho National Engineering Laboratory for this purpose. The software measures the undeveloped hydropower resources available in the United States, using uniform criteria for measurement. The software was developed and tested using hydropower information and data provided by the Southwestern Power Administration. It is a menu-driven software program that allows the personal computer user to assign environmental attributes to potential hydropower sites, calculate development suitability factors for each site based on the environmental attributes present, and generate reports based on these suitability factors. This report details the resource assessment results for the Commonwealth of Massachusetts.

The importance of hydropower in Austria

International Nuclear Information System (INIS)

Kobau, R.; Pirker, O.; Spolwind, R.; Weiss, B.

2009-01-01

This article discusses the importance of hydropower-based power generation in Austria as a clean and emission-free source of electricity. The contribution made to total electricity generation is examined and figures are quoted. Hydropower is provided from both storage dams and run-of-river power stations such as those on the river Danube. The use of the various types of hydropower in connection with their economic optimisation, for example for the supply of valuable peak power, is discussed. The promotion of hydropower within the scope of European climate-protection efforts is examined. Projects concerning the augmentation of hydropower capacities are discussed and three exemplary projects are briefly described. Finally, the situation in Austria is compared with that to be found in neighbouring Switzerland.

US hydropower resource assessment for Texas

Energy Technology Data Exchange (ETDEWEB)

Francfort, J.E.

1993-12-01

The Department of Energy is developing an estimate of the hydropower development potential in this country. The Hydropower Evaluation Software (HES) is a computer model that was developed by the Idaho National Engineering Laboratory for this purpose. The HES measures the potential hydropower resources available in the United States, using uniform criteria for measurement. The software was developed and tested using hydropower information and data provided by the Southwestern Power Administration. It is a dBASE menu-driven software application that allows the personal computer user to assign environmental attributes to potential hydropower sites, calculate development suitability factors for each site based on the environmental attributes present, and generate reports based on these suitability factors. This report details the resource assessment results for the state of Texas.

US hydropower resource assessment for Montana

Energy Technology Data Exchange (ETDEWEB)

Francfort, J.E.

1993-12-01

The Department of Energy is developing an estimate of the hydropower development potential in this country. The Hydropower Evaluation Software (HES) is a computer model that was developed by the Idaho National Engineering Laboratory for this purpose. The HES measures the potential hydropower resources available in the United States, using uniform criteria for measurement. The software was developed and tested using hydropower information and data provided by the Southwestern Power Administration. It is a dBASE menu-driven software application that allows the personal computer user to assign environmental attributes to potential hydropower sites, calculate development suitability factors for each site based on the environmental attributes present, and generate reports based on these suitability factors. This report details the resource assessment results for the state of Montana.

US hydropower resource assessment for Kansas

Energy Technology Data Exchange (ETDEWEB)

Francfort, J.E.

1993-12-01

The Department of Energy is developing an estimate of the hydropower development potential in this country. The Hydropower Evaluation Software (HES) is a computer model that was developed by the Idaho National Engineering Laboratory for this purpose. The HES measures the potential hydropower resources available in the United States, using uniform criteria for measurement. The software was developed and tested using hydropower information and data provided by the Southwestern Power Administration. It is a dBASE menu-driven software application that allows the personal computer user to assign environmental attributes to potential hydropower sites, calculate development suitability factors for each site based on the environmental attributes present, and generate reports based on these suitability factors. This report details the resource assessment results for the state of Kansas.

Hydropower - internalized costs and externalized benefits

International Nuclear Information System (INIS)

Koch, F.H.

2002-01-01

The benefits of hydropower consist of the minimal level of noxious and greenhouse gas emissions, it's energy security from political instability, and its renewable, non-depletable nature. The costs of hydropower consist of negative effects on the river ecosystem and of social changes in communities in the vicinity of large projects. Public awareness of these costs has increased dramatically during the past two decades, and new hydro projects will not get approval unless adequate mitigation measures are taken to avoid, offset, or compensate for adverse environmental and social effects. To a very large extent, the hydropower industry has internalized what were previously social and environmental externalities. However, hydropower operators do not receive any compensation for the benefits, and to date their competitors (coal, natural gas, oil) have not been required to internalize their adverse environmental externalities. (emissions, depletion of supplies, and sometimes dependence on imported primary energy sources). This creates an uneven playing field, and the hydropower industry enthusiastically welcomes a discussion of this issue, and eventually measures to rectify the situation. The IEA Hydropower Agreement has completed a major international study on the environmental and social impacts of hydropower, and one major component of this study was a Life Cycle Assessment and comparison of all the most important electricity generation technologies. (author)

Hydropower research and development

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-03-01

This report is a compilation of information on hydropower research and development (R and D) activities of the Federal government and hydropower industry. The report includes descriptions of on-going and planned R and D activities, 1996 funding, and anticipated future funding. Summary information on R and D projects and funding is classified into eight categories: fish passage, behavior, and response; turbine-related; monitoring tool development; hydrology; water quality; dam safety; operations and maintenance; and water resources management. Several issues in hydropower R and D are briefly discussed: duplication; priorities; coordination; technical/peer review; and technology transfer/commercialization. Project information sheets from contributors are included as an appendix.

Hydropower Resource Assessment of Brazilian Streams

Energy Technology Data Exchange (ETDEWEB)

Douglas G. Hall

2011-09-01

The Idaho National Laboratory (INL) in collaboration with the U.S. Geological Survey (USGS) with the assistance of the Empresa de Pesquisa Energetica (EPE) and the Agencia Nacional de Energia Electrica (ANEEL) has performed a comprehensive assessment of the hydropower potential of all Brazilian natural streams. The methodology by which the assessment was performed is described. The results of the assessment are presented including an estimate of the hydropower potential for all of Brazil, and the spatial distribution of hydropower potential thus providing results on a state by state basis. The assessment results have been incorporated into a geographic information system (GIS) application for the Internet called the Virtual Hydropower Prospector do Brasil. VHP do Brasil displays potential hydropower sites on a map of Brazil in the context of topography and hydrography, existing power and transportation infrastructure, populated places and political boundaries, and land use. The features of the application, which includes tools for finding and selecting potential hydropower sites and other features and displaying their attributes, is fully described.

Hydropower, an integral part of Canada's climate change strategy

International Nuclear Information System (INIS)

Fortin, P.

1999-01-01

The development and implementation of a climate change policy could be among the most far-reaching environmental initiatives ever embarked upon in Canada and abroad. If Canada is to stabilize or reduce its Greenhouse Gas (GHG) emissions over the long term, a significant adjustment to Canadian industry will be required as we move away from fossil fuel-intensive and GHG producing activities. Future hydroelectric projects provide Canada with a unique opportunity to significantly reduce the costs associated with stabilizing its GHG emissions. In addition, the energy storage and dispatchability associated with hydropower can support development of other low emitting renewable resources such as wind and solar. This document discusses the potential role of hydropower as a tool to reduce emissions, recommends action to reduce barriers facing hydropower and comments on some of the policy tools available to manage Canada's GHG emissions. (author)

Ultra-low magnetic damping in metallic and half-metallic systems

Science.gov (United States)

Shaw, Justin

The phenomenology of magnetic damping is of critical importance to devices which seek to exploit the electronic spin degree of freedom since damping strongly affects the energy required and speed at which a device can operate. However, theory has struggled to quantitatively predict the damping, even in common ferromagnetic materials. This presents a challenge for a broad range of applications in magnonics, spintronics and spin-orbitronics that depend on the ability to precisely control the damping of a material. I will discuss our recent work to precisely measure the intrinsic damping in several metallic and half-metallic material systems and compare experiment with several theoretical models. This investigation uncovered a metallic material composed of Co and Fe that exhibit ultra-low values of damping that approach values found in thin film YIG. Such ultra-low damping is unexpected in a metal since magnon-electron scattering dominates the damping in conductors. However, this system possesses a distinctive feature in the bandstructure that minimizes the density of states at the Fermi energy n(EF). These findings provide the theoretical framework by which such ultra-low damping can be achieved in metallic ferromagnets and may enable a new class of experiments where ultra-low damping can be combined with a charge current. Half-metallic Heusler compounds by definition have a bandgap in one of the spin channels at the Fermi energy. This feature can also lead to exceptionally low values of the damping parameter. Our results show a strong correlation of the damping with the order parameter in Co2MnGe. Finally, I will provide an overview of the recent advances in achieving low damping in thin film Heusler compounds.

Small hydropower station in Schluein, Switzerland

International Nuclear Information System (INIS)

Merz, F.; Thoeny, F.

2007-04-01

This preliminary study elaborated for the Swiss Federal Office of Energy (SFOE) describes a project concerning the building of a small-scale hydropower installation in Schluein in the Grisons, Switzerland. The requirements placed on the water intake point in this mountainous region are discussed. The installation includes a 1230 metre long pressurised conduit and uses a multi-jet Pelton turbine to provide 720 kW of electrical power, the hydraulic head amounting to 140 m. The paper discusses the amounts of water available over the year, production costs and the economic feasibility of the project. The power production is estimated to 3,150,000 kWh/y. Environmental aspects are examined and details still to be defined are briefly mentioned.

Influence of El Niño Southern Oscillation on global hydropower production

Science.gov (United States)

Ng, Jia Yi; Turner, Sean; Galelli, Stefano

2016-04-01

Hydropower contributes significantly to meeting the world's energy demand, accounting for at least 16% of total electrical output. Its role as a mature and cost competitive renewable energy source is expected to become increasingly important as the world transits to a low-carbon economy. A key component of hydropower production is runoff, which is highly dependent on precipitation and other climate variables. As such, it becomes critical to understand how the drivers of climate variability impact hydropower production. One globally-important driver is the El Niño Southern Oscillation (ENSO). While it is known that ENSO influences hydrological processes, the potential value of its associated teleconnection in design related tasks has yet to be explored at the global scale. Our work seeks to characterize the impact of ENSO on global hydropower production so as to quantify the potential for increased production brought about by incorporating climate information within reservoir operating models. We study over 1,500 hydropower reservoirs - representing more than half the world's hydropower capacity. A historical monthly reservoir inflow time series is assigned to each reservoir from a 0.5 degree gridded global runoff dataset. Reservoir operating rules are designed using stochastic dynamic programming, and storage dynamics are simulated to assess performance under the climate conditions of the 20th century. Results show that hydropower reservoirs in the United States, Brazil, Argentina, Australia, and Eastern China are strongly influenced by ENSO episodes. Statistically significant lag correlations between ENSO indicators and hydropower production demonstrate predictive skill with lead times up to several months. Our work highlights the potential for using these indicators to increase the contribution of existing hydropower plants to global energy supplies.

Ultra-low dose dual-source high-pitch computed tomography of the paranasal sinus: diagnostic sensitivity and radiation dose

International Nuclear Information System (INIS)

Schulz, Boris; Zangos, Stefan; Friedrichs, Ingke; Bauer, Ralf W.; Kerl, Matthias; Vogl, Thomas J.; Martin M Mack, Martin M.; Potente, Stefan

2012-01-01

Background: Today's gold standard for diagnostic imaging of inflammatory diseases of the paranasal sinus is computed tomography (CT). Purpose: To evaluate diagnostic sensitivity and radiation dose of an ultra-low dose dual-source CT technique. Material and Methods: Paranasal sinuses of 14 cadaveric heads were independently evaluated by two readers using a modern dual-source CT with lowest reasonable dosage in high-pitch mode (100 kV, 10 mAs, collimation 0.6 mm, pitch value 3.0). Additionally the head part of an anthropomorphic Alderson-Rando phantom was equipped with thermoluminescent detectors to measure radiation exposure to the eye lenses and thyroid gland. Results: Diagnostic accuracy regarding sinusoidal fluid, nasal septum deviation, and mucosal swelling was 100%. Mastoid fluid was detected in 76% and 92%, respectively. In the phantom study, average measured eye lens dosage was 0.64 mGy; radiation exposure of the thyroid gland was 0.085 mGy. Conclusion: Regarding evaluation of inflammatory diseases of the paranasal sinus this study indicates sufficient accuracy of the proposed CT protocol at a very low dosage level

assessment of the hydropower potential of kangimi reservoir

African Journals Online (AJOL)

2012-11-03

Nov 3, 2012 ... other renewable energy sources such as wind, small or mini hydropower ... plied to Kaduna treatment plant during the periods of low flow in River .... following functional reservoir relationships that are very site specific: i.

Ultra-low-energy wide electron exposure unit

International Nuclear Information System (INIS)

Yonago, Akinobu; Oono, Yukihiko; Tokunaga, Kazutoshi; Kishimoto, Junichi; Wakamoto, Ikuo

2001-01-01

Heat and ultraviolet ray processes are used in surface dryness of paint, surface treatment of construction materials and surface sterilization of food containers. A process using a low-energy wide-area electron beam (EB) has been developed that features high speed and low drive cost. EB processing is not widespread in general industry, however, due to high equipment cost and difficult maintenance. We developed an ultra-low-energy wide-area electron beam exposure unit, the Mitsubishi Wide Electron Exposure Unit (MIWEL) to solve these problems. (author)

Hydropower and its development

Directory of Open Access Journals (Sweden)

Janusz Steller

2013-09-01

Full Text Available Even if the documented history of hydropower reaches back as far as 5000 years ago, it owes its rapid acceleration in growth to the industrial revolution at the beginning of the nineteenth century. The end of the twentieth century brought about new challenges associated, on the one hand, with a growing demand for ancillary grid services, and on the other with new requirements for mitigating the environmental impact. Hydropower technology expansion had come about in a manner aiming to at least partially exploit the mechanical energy of sea and ocean waters. This study points out to the most important trends in and barriers to hydropower development, with particular focus on the situation in Poland. This author sees the main threats to Polish hydropower development in how it is perceived solely through the prism of the generation of a particular volume of green energy, and a total underestimation of the quality of electricity supply and the numerous non-energy benefits resulting from hydroelectric power plant operation.

PHYSICS WITH ULTRA-LOW ENERGY ANTIPROTONS

Energy Technology Data Exchange (ETDEWEB)

M. HOLZSCHEITER

2001-02-01

In this report the author describes the current status of the antiproton deceleration (AD) facility at CERN, and highlights the physics program with ultra-low energy antiproton at this installation. He also comments on future possibilities provided higher intensity antiproton beams become available at Fermilab, and review possibilities for initial experiments using direct degrading of high energy antiprotons in material has been developed and proven at CERN.

Present situation and future prospect of hydropower in China

Energy Technology Data Exchange (ETDEWEB)

Huang, Hailun; Yan, Zheng [Department of Electrical Engineering, Shanghai Jiaotong University, Shanghai 200240 (China)

2009-08-15

Hydropower is a clean and renewable energy source. Considering the economic, technical and environmental benefits of hydropower, most countries give priority to its development. China has the richest hydro resources on the planet with a total theoretical hydropower potential of 694 GW. Developing hydropower is of great importance to alleviate the energy crisis and environmental pollution resulting from the rapid economic growth of China in the 21st century. This paper provides a survey of hydropower development in China. Over the last five decades, China's hydropower has developed quickly. The installed capacity of hydropower is 145.26 GW presently. Some large hydropower plants have been in operation and many are still under construction, including the Three Gorges Project (TGP) and pumped-storage power stations. Small hydropower development accelerates rural electrification of this country. (author)

Hydropower and local community : A case study of the Kamchay dam, a China-funded hydropower project in Cambodia

NARCIS (Netherlands)

Pheakdey, Heng

2017-01-01

To solve its chronic power shortage, the Government of Cambodia has placed the development of hydropower as one of the national priorities. With a total of US$2.4bn in investment, China is the most prominent player in hydropower development in Cambodia. The increase of hydropower projects and

Climate impacts on hydropower and consequences for global electricity supply investment needs

Energy Technology Data Exchange (ETDEWEB)

Turner, Sean W. D.; Hejazi, Mohamad; Kim, Son H.; Clarke, Leon; Edmonds, Jae

2017-12-01

Recent progress in global scale hydrological and dam modeling has allowed for the study of climate change impacts on global hydropower production. Here we explore the possible consequences of these impacts for the electricity supply sector. Regional hydropower projections are developed for two emissions scenarios by forcing a coupled global hydrological and dam model with downscaled, bias-corrected climate realizations derived from sixteen general circulation models. Consequent impacts on power sector composition and associated emissions and investment costs are explored using the Global Change Assessment Model (GCAM). Changes in hydropower generation resulting from climate change can shift power demands onto and away from carbon intensive technologies, resulting in significant impacts on power sector CO2 emissions for certain world regions—primarily those located in Latin America, as well as Canada and parts of Europe. Reduced impacts of climate change on hydropower production under a low emissions scenario coincide with increased costs of marginal power generating capacity—meaning impacts on power sector investment costs are similar for high and low emissions scenarios. Individual countries where impacts on investment costs imply significant risks or opportunities are identified.

Hydropower development in India

Energy Technology Data Exchange (ETDEWEB)

Saxena, Praveen [Govt. of India, New Delhi (India). Ministry of New and Renewable Energy], E-mail: psaxena_98@yahoo.com; Kumar, Arun [Indian Institute of Technology Roorkee, Uttarakhand (India). Alternate Hydro Energy Centre], E-mail: aheciitr@gmail.com

2011-04-15

India is posed for large deployment of hydropower in present conducive policy and investment environment. Growing energy demand and concern for carbon emission is making hydropower development more favorable. The Government of India is ensuring a good performance of the new SHP stations by linking the incentives to the SHP developers with the performance of the station. (author)

FORMULATING ULTRA-LOW-VOC WOOD FURNITURE COATINGS

Science.gov (United States)

The article discusses the formulation of ultra-low volatile organic compound (VOC) wood furniture coatings. The annual U.S. market for wood coatings is about 240, 000 cu m (63 million gal). In this basis, between 57 and 91 million kg (125 and 200 million lb) of VOCs are emitted i...

China's rising hydropower demand challenges water sector

NARCIS (Netherlands)

Liu, Junguo; Zhao, Dandan; Gerbens-Leenes, Winnie; Guan, Dabo

2015-01-01

Demand for hydropower is increasing, yet the water footprints (WFs) of reservoirs and hydropower, and their contributions to water scarcity, are poorly understood. Here, we calculate reservoir WFs (freshwater that evaporates from reservoirs) and hydropower WFs (the WF of hydroelectricity) in China

State Models to Incentivize and Streamline Small Hydropower Development

Energy Technology Data Exchange (ETDEWEB)

Curtis, Taylor [National Renewable Energy Lab. (NREL), Golden, CO (United States); Levine, Aaron [National Renewable Energy Lab. (NREL), Golden, CO (United States); Johnson, Kurt [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2017-10-31

In 2016, the hydropower fleet in the United States produced more than 6 percent (approximately 265,829 gigawatt-hours [GWh]) of the total net electricity generation. The median-size hydroelectric facility in the United States is 1.6 MW and 75 percent of total facilities have a nameplate capacity of 10 MW or less. Moreover, the U.S. Department of Energy's Hydropower Vision study identified approximately 79 GW hydroelectric potential beyond what is already developed. Much of the potential identified is at low-impact new stream-reaches, existing conduits, and non-powered dams with a median project size of 10 MW or less. To optimize the potential and value of small hydropower development, state governments are crafting policies that provide financial assistance and expedite state and federal review processes for small hydroelectric projects. This report analyzes state-led initiatives and programs that incentivize and streamline small hydroelectric development.

Hydropower: Setting a Course for Our Energy Future

Energy Technology Data Exchange (ETDEWEB)

2004-07-01

Hydropower is an annual publication that provides an overview of the Department of Energy's Hydropower Program. The mission of the program is to conduct research and development that will increase the technical, societal, and environmental benefits of hydropower and provide cost-competitive technologies that enable the development of new and incremental hydropower capacity.

Ultra Low Energy Binary Decision Diagram Circuits Using Few Electron Transistors

Science.gov (United States)

Saripalli, Vinay; Narayanan, Vijay; Datta, Suman

Novel medical applications involving embedded sensors, require ultra low energy dissipation with low-to-moderate performance (10kHz-100MHz) driving the conventional MOSFETs into sub-threshold operation regime. In this paper, we present an alternate ultra-low power computing architecture using Binary Decision Diagram based logic circuits implemented using Single Electron Transistors (SETs) operating in the Coulomb blockade regime with very low supply voltages. We evaluate the energy - performance tradeoff metrics of such BDD circuits using time domain Monte Carlo simulations and compare them with the energy-optimized CMOS logic circuits. Simulation results show that the proposed approach achieves better energy-delay characteristics than CMOS realizations.

Extending ultra-short pulse laser texturing over large area

Energy Technology Data Exchange (ETDEWEB)

Mincuzzi, G., E-mail: girolamo.mincuzzi@alphanov.com; Gemini, L.; Faucon, M.; Kling, R.

2016-11-15

Highlights: • We carried out metal surface texturing (Ripples, micro grooves, Spikes) using a high power, high repetition rate, industrial, Ultra-short pulses laser. • Extremely Fast processing is shown (Laser Scan speed as high as 90 m/s) with a polygon scanner head. • Stainless steel surface blackening with Ultra-short pulses laser has been obtained with unprecedented scanspeed. • Full SEM surface characterization was carried out for all the different structures obtained. • Reflectance measurements were carried out to characterize surface reflectance. - Abstract: Surface texturing by Ultra-Short Pulses Laser (UPL) for industrial applications passes through the use of both fast beam scanning systems and high repetition rate, high average power P, UPL. Nevertheless unwanted thermal effects are expected when P exceeds some tens of W. An interesting strategy for a reliable heat management would consists in texturing with a low fluence values (slightly higher than the ablation threshold) and utilising a Polygon Scanner Heads delivering laser pulses with unrepeated speed. Here we show for the first time that with relatively low fluence it is possible over stainless steel, to obtain surface texturing by utilising a 2 MHz femtosecond laser jointly with a polygonal scanner head in a relatively low fluence regime (0.11 J cm{sup −2}). Different surface textures (Ripples, micro grooves and spikes) can be obtained varying the scan speed from 90 m s{sup −1} to 25 m s{sup −1}. In particular, spikes formation process has been shown and optimised at 25 m s{sup −1} and a full morphology characterization by SEM has been carried out. Reflectance measurements with integrating sphere are presented to compare reference surface with high scan rate textures. In the best case we show a black surface with reflectance value < 5%.

Greenhouse gas emissions of hydropower in the Mekong River Basin

Science.gov (United States)

Räsänen, Timo A.; Varis, Olli; Scherer, Laura; Kummu, Matti

2018-03-01

The Mekong River Basin in Southeast Asia is undergoing extensive hydropower development, but the magnitudes of related greenhouse gas emissions (GHG) are not well known. We provide the first screening of GHG emissions of 141 existing and planned reservoirs in the basin, with a focus on atmospheric gross emissions through the reservoir water surface. The emissions were estimated using statistical models that are based on global emission measurements. The hydropower reservoirs (119) were found to have an emission range of 0.2-1994 kg CO2e MWh-1 over a 100 year lifetime with a median of 26 kg CO2e MWh-1. Hydropower reservoirs facilitating irrigation (22) had generally higher emissions reaching over 22 000 kg CO2e MWh-1. The emission fluxes for all reservoirs (141) had a range of 26-1813 000 t CO2e yr-1 over a 100 year lifetime with a median of 28 000 t CO2e yr-1. Altogether, 82% of hydropower reservoirs (119) and 45% of reservoirs also facilitating irrigation (22) have emissions comparable to other renewable energy sources (equalling even the emission from fossil fuel power plants (>380 kg CO2e MWh-1). These results are tentative and they suggest that hydropower in the Mekong Region cannot be considered categorically as low-emission energy. Instead, the GHG emissions of hydropower should be carefully considered case-by-case together with the other impacts on the natural and social environment.

Food provisioning experiences of ultra poor female heads of household living in Bangladesh.

Science.gov (United States)

McIntyre, Lynn; Rondeau, Krista; Kirkpatrick, Sharon; Hatfield, Jennifer; Islam, Khaled Shamsul; Huda, Syed Nazmul

2011-03-01

Ultra poor women in Bangladesh are especially vulnerable to poverty and food insecurity, and they have generally been excluded from recent improvements in hunger and poverty rates in the country. An examination of the food provisioning narratives of 43 ultra poor female heads of household in Bangladesh was conducted in order to deepen understanding of this obstacle to the country's achievement of the First Millennium Development Goal. All participants were the household's sole income provider, had dependent children, and earned less than $1 USD per day. Women were purposively selected based on occupational group, context, and personal characteristics. Ethnographic interviews were conducted in January and February, 2008. Analysis of women's accounts of their daily food routine revealed chronic and pervasive food insecurity punctuated by acute episodes of absolute food deprivation that resulted from seasonal fluctuations in earnings, rising food prices, illness disrupting work, and healthcare costs. Women's accounts of their daily food provisioning experiences suggested compromises in, and trade-offs between, multiple basic needs as a result of inadequate income. Women were further constrained by social norms and gender roles that influenced their ability to work outside the home. Our method of inquiry led us to construct an organizing framework that extends knowledge of ultra poor women in Bangladesh's complex and multi-sphered experience of poverty and food insecurity. Based on these findings, we propose a strategy called whole person development (WPD), which seeks small adjustments to services, programs, and policies based on leverage points identified through in-depth narratives. Copyright © 2011 Elsevier Ltd. All rights reserved.

System and method for magnetic current density imaging at ultra low magnetic fields

Science.gov (United States)

Espy, Michelle A.; George, John Stevens; Kraus, Robert Henry; Magnelind, Per; Matlashov, Andrei Nikolaevich; Tucker, Don; Turovets, Sergei; Volegov, Petr Lvovich

2016-02-09

Preferred systems can include an electrical impedance tomography apparatus electrically connectable to an object; an ultra low field magnetic resonance imaging apparatus including a plurality of field directions and disposable about the object; a controller connected to the ultra low field magnetic resonance imaging apparatus and configured to implement a sequencing of one or more ultra low magnetic fields substantially along one or more of the plurality of field directions; and a display connected to the controller, and wherein the controller is further configured to reconstruct a displayable image of an electrical current density in the object. Preferred methods, apparatuses, and computer program products are also disclosed.

Development potential for hydropower

International Nuclear Information System (INIS)

Laufer, F.; Groetzinger, S.; Peter, M.; Schmutz, A.

2004-11-01

This comprehensive report for the Swiss Federal Office of Energy (SFOE) takes a look at the potential for the development of hydropower in Switzerland. The report updates the energy perspectives made ten years earlier. An overview of Swiss electricity production and consumption is presented and the proportion provided by hydropower is noted. Figures on installed capacity and import/export quantities are presented and discussed. Technological developments and the economical frameworks involved are discussed, as are regulatory measures that can be taken. Theoretical and technically realisable potentials for increased use of hydropower are discussed. The methods used to do this are examined. Strategies and measures to be taken are listed and discussed. An appendix includes data sheets on power plant modelling, including examples

An ultra-low-power CMOS temperature sensor for RFID applications

Energy Technology Data Exchange (ETDEWEB)

Xu Conghui; Gao Peijun; Che Wenyi; Tan Xi; Yan Na; Min Hao, E-mail: yanna@fudan.edu.c [State Key Laboratory of ASIC and System, Fudan University, Shanghai 201203 (China)

2009-04-15

An ultra-low-power CMOS temperature sensor with analog-to-digital readout circuitry for RFID applications was implemented in a 0.18-mum CMOS process. To achieve ultra-low power consumption, an error model is proposed and the corresponding novel temperature sensor front-end with a new double-measure method is presented. Analog-to-digital conversion is accomplished by a sigma-delta converter. The complete system consumes only 26 muA and 1.8 V for continuous operation and achieves an accuracy of +-0.65 deg. C from -20 to 120 deg. C after calibration at one temperature.

An ultra-low-power CMOS temperature sensor for RFID applications

International Nuclear Information System (INIS)

Xu Conghui; Gao Peijun; Che Wenyi; Tan Xi; Yan Na; Min Hao

2009-01-01

An ultra-low-power CMOS temperature sensor with analog-to-digital readout circuitry for RFID applications was implemented in a 0.18-μm CMOS process. To achieve ultra-low power consumption, an error model is proposed and the corresponding novel temperature sensor front-end with a new double-measure method is presented. Analog-to-digital conversion is accomplished by a sigma-delta converter. The complete system consumes only 26 μA and 1.8 V for continuous operation and achieves an accuracy of ±0.65 deg. C from -20 to 120 deg. C after calibration at one temperature.

PREDICTION OF TOTAL DISSOLVED GAS EXCHANGE AT HYDROPOWER DAMS

Energy Technology Data Exchange (ETDEWEB)

Hadjerioua, Boualem [ORNL; Pasha, MD Fayzul K [ORNL; Stewart, Kevin M [ORNL; Bender, Merlynn [Bureau of Reclamation; Schneider, Michael L. [U.S. Army Corps of Engineers

2012-07-01

powerhouse flows in the tailrace channel and resultant exchange in route to the next downstream dam. Currently, there exists a need to summarize the general finding from operational and structural TDG abatement programs conducted throughout the CRB and for the development of a generalized prediction model that pools data collected at multiple projects with similar structural attributes. A generalized TDG exchange model can be tuned to specific projects and coupled with water regulation models to allow the formulation of optimal daily water regulation schedules subject to water quality constraints for TDG supersaturation. A generalized TDG exchange model can also be applied to other hydropower dams that affect TDG pressures in tailraces and can be used to develop alternative operational and structural measures to minimize TDG generation. It is proposed to develop a methodology for predicting TDG levels downstream of hydropower facilities with similar structural properties as a function of a set of variables that affect TDG exchange; such as tailwater depth, spill discharge and pattern, project head, and entrainment of powerhouse releases. TDG data from hydropower facilities located throughout the northwest region of the United States will be used to identify relationships between TDG exchange and relevant dependent variables. Data analysis and regression techniques will be used to develop predictive TDG exchange expressions for various structural categories.

U.S. hydropower resource assessment for Nevada

Energy Technology Data Exchange (ETDEWEB)

Conner, A.M.; Francfort, J.E.

1997-10-01

The US Department of Energy is developing an estimate of the undeveloped hydropower potential in the US. The Hydropower Evaluation Software (HES) is a computer model that was developed by the Idaho National Engineering Laboratory for this purpose. HES measures the undeveloped hydropower resources available in the US, using uniform criteria for measurement. The software was developed and tested using hydropower information and data provided by the Southwestern Power Administration. It is a menu-driven program that allows the personal computer user to assign environmental attributes to potential hydropower sites, calculate development suitability factors for each site based on the environmental attributes present, and generate reports based on these suitability factors. This report describes the resource assessment results for the State of Nevada.

U.S. hydropower resource assessment for Idaho

Energy Technology Data Exchange (ETDEWEB)

Conner, A.M.; Francfort, J.E.

1998-08-01

The US Department of Energy is developing an estimate of the undeveloped hydropower potential in the US. The Hydropower Evaluation Software (HES) is a computer model that was developed by the Idaho National Engineering and Environmental Laboratory for this purpose. HES measures the undeveloped hydropower resources available in the US, using uniform criteria for measurement. The software was developed and tested using hydropower information and data provided by the Southwestern Power Administration. It is a menu-driven program that allows the personal computer user to assign environmental attributes to potential hydropower sites, calculate development suitability factors for each site based on the environmental attributes present, and generate reports based on these suitability factors. This report describes the resource assessment results for the State of Idaho.

US hydropower resource assessment for New Jersey

Energy Technology Data Exchange (ETDEWEB)

Connor, A.M.; Francfort, J.E.

1996-03-01

The Department of Energy is developing an estimate of the undeveloped hydropower potential in this country. The Hydropower Evaluation Software is a computer model that was developed by the Idaho National Engineering Laboratory for this purpose. The software measures the undeveloped hydropower resources available in the United States, using uniform criteria for measurement. The software was developed and tested using hydropower information and data provided by the Southwestern Power Administration. It is a menu-driven software program that allows the personal computer user to assign environmental attributes to potential hydropower sites, calculate development suitability factors for each site based on the environmental attributes present, and generate reports based on these suitability factors. This report details the resource assessment results for the State of New Jersey.

Greaseless Bushings for Hydropower Applications: Program, Testing, and Results

National Research Council Canada - National Science Library

Jones, John

1999-01-01

...) bushings at its hydropower and navigation facilities. Products of this type currently on the market, however, were not specifically developed for the high-load, low-speed oscillating operating conditions typical for power-generation machinery...

World Small Hydropower Development Report

Energy Technology Data Exchange (ETDEWEB)

Liu, Heng; Esser, Lara [ICSGP (China); Masera, Diego [UNIDO, Vienna (Austria)

2013-07-01

Currently, small hydropower plants with a capacity of 10 MW, exist in 148 countries or territories worldwide. Four other countries have been identified with resource potential. This report aims to identify the development status and resource potential of small hydro in various countries, territories and regions throughout the world. Working with experts at the ground level to compile and share existing information, experiences and challenges, one comprehensive report was created. Decision-makers, stakeholders and potential investors clearly need this comprehensive information to more effectively promote small hydropower as a renewable and rural energy source for sustainable development and to overcome the existing development barriers. The findings of this report show that small hydropower potential globally is approximated at almost 173 GW. The figure is arrived by totaling data from a wide range of sources with potential compromise of data integrity to varying degrees. For example, research data on economically feasible potential were more readily available in developed countries than those in the least developed or developing countries. More than half of the world's known hydropower potential is located in Asia, around one third can be found in Europe and the Americas. It is possible in the future that more small hydropower potential might be identified both on the African and American continents. The installed small hydropower capacity (up to 10 MW) is estimated to be 75 GW in 2011/2012. The report provides detailed data for each country/region, including recommendations on the national, regional and international level.

World Small Hydropower Development Report

Energy Technology Data Exchange (ETDEWEB)

Liu, Heng; Esser, Lara (ICSGP (China)); Masera, Diego (UNIDO, Vienna (Austria))

2013-07-01

Currently, small hydropower plants with a capacity of 10 MW, exist in 148 countries or territories worldwide. Four other countries have been identified with resource potential. This report aims to identify the development status and resource potential of small hydro in various countries, territories and regions throughout the world. Working with experts at the ground level to compile and share existing information, experiences and challenges, one comprehensive report was created. Decision-makers, stakeholders and potential investors clearly need this comprehensive information to more effectively promote small hydropower as a renewable and rural energy source for sustainable development and to overcome the existing development barriers. The findings of this report show that small hydropower potential globally is approximated at almost 173 GW. The figure is arrived by totaling data from a wide range of sources with potential compromise of data integrity to varying degrees. For example, research data on economically feasible potential were more readily available in developed countries than those in the least developed or developing countries. More than half of the world's known hydropower potential is located in Asia, around one third can be found in Europe and the Americas. It is possible in the future that more small hydropower potential might be identified both on the African and American continents. The installed small hydropower capacity (up to 10 MW) is estimated to be 75 GW in 2011/2012. The report provides detailed data for each country/region, including recommendations on the national, regional and international level.

Exemplary Design Envelope Specification for Standard Modular Hydropower Technology

Energy Technology Data Exchange (ETDEWEB)

Witt, Adam M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Smith, Brennan T. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Tsakiris, Achilleas [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Univ. of Tennessee, Knoxville, TN (United States); Papanicolaou, Thanos [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Univ. of Tennessee, Knoxville, TN (United States); Pries, Jason L. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Burress, Timothy A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Stewart, Kevin M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Lee, Kyutae [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); DeNeale, Scott T. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bevelhimer, Mark S. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Pracheil, Brenda M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); McManamay, Ryan A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Ekici, Kivanc [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Univ. of Tennessee, Knoxville, TN (United States); Kutz, Benjamin [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Univ. of Tennessee, Knoxville, TN (United States); Curd, Shelaine L. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bishop, Norm [Knight Piesold, Denver, CO (United States); Welch, Tim [U.S. Department of Energy (DOE), Washington, DC (United States). Office of Energy Efficiency and Renewable Energy (EERE); Rabon, Daniel [U.S. Department of Energy (DOE), Washington, DC (United States). Office of Energy Efficiency and Renewable Energy (EERE); Fernandez, Alisha [McKeown and Associates, Moberly, MO (United States)

2017-02-01

Hydropower is an established, affordable renewable energy generation technology supplying nearly 18% of the electricity consumed globally. A hydropower facility interacts continuously with the surrounding water resource environment, causing alterations of varying magnitude in the natural flow of water, energy, fish, sediment, and recreation upstream and downstream. A universal challenge in facility design is balancing the extraction of useful energy and power system services from a stream with the need to maintain ecosystem processes and natural environmental function. On one hand, hydroelectric power is a carbon-free, renewable, and flexible asset to the power system. On the other, the disruption of longitudinal connectivity and the artificial barrier to aquatic movement created by hydraulic structures can produce negative impacts that stress fresh water environments. The growing need for carbon-free, reliable, efficient distributed energy sources suggests there is significant potential for hydropower projects that can deploy with low installed costs, enhanced ecosystem service offerings, and minimal disruptions of the stream environment.

Reaching ultra low phosphorus concentrations by filtration techniques

NARCIS (Netherlands)

Scherrenberg, S.M.

2011-01-01

This research deals with tertiary treatment techniques used for the removal of phosphorus from wastewater treatment plant (WWTP) effluent. The main objective of this research is to obtain ultra low total phosphorus (<0.15 mg total phosphorus/L) concentrations by coagulation, flocculation and

Hydro-power

International Nuclear Information System (INIS)

Piro, P.

2010-01-01

On average the hydro-power sector produces 12% of the electrical power in France. A quarter of this production might pass to another operator than EDF because the end of some grants is nearing (2012 for 12 installations). In France the power of rivers belongs to the state that gives operators grants to harness it. The allowance lasts 75 years usually but for installations below 4.5 MW a permanent and definitive grant is allowed. Most installations are ancient and their investment have been paid off since a long, so hydro-power is the most profitable renewable energy in France. A lot of bidders are expected. Each bid will be assessed on 3 criteria: -) the global energy efficiency of the waterfall, -) a balanced management of the water resource, and -) an economic and financial offer to the state. The balance between the different uses of water is getting more delicate to reach and this renewal of grants will be an opportunity for the state to impose a better preservation of the environment. In July 2008, the French government announced a program for the re launching of the hydro-power, this program has been reduced and now only 3000 GWh supplementary are expected by 2020. (A.C.)

China's rising hydropower demand challenges water sector.

Science.gov (United States)

Liu, Junguo; Zhao, Dandan; Gerbens-Leenes, P W; Guan, Dabo

2015-07-09

Demand for hydropower is increasing, yet the water footprints (WFs) of reservoirs and hydropower, and their contributions to water scarcity, are poorly understood. Here, we calculate reservoir WFs (freshwater that evaporates from reservoirs) and hydropower WFs (the WF of hydroelectricity) in China based on data from 875 representative reservoirs (209 with power plants). In 2010, the reservoir WF totaled 27.9 × 10(9) m(3) (Gm(3)), or 22% of China's total water consumption. Ignoring the reservoir WF seriously underestimates human water appropriation. The reservoir WF associated with industrial, domestic and agricultural WFs caused water scarcity in 6 of the 10 major Chinese river basins from 2 to 12 months annually. The hydropower WF was 6.6 Gm(3) yr(-1) or 3.6 m(3) of water to produce a GJ (10(9) J) of electricity. Hydropower is a water intensive energy carrier. As a response to global climate change, the Chinese government has promoted a further increase in hydropower energy by 70% by 2020 compared to 2012. This energy policy imposes pressure on available freshwater resources and increases water scarcity. The water-energy nexus requires strategic and coordinated implementations of hydropower development among geographical regions, as well as trade-off analysis between rising energy demand and water use sustainability.

Hydropower externalities: a meta analysis

NARCIS (Netherlands)

Mattmann, M.; Logar, I.; Brouwer, R.

2016-01-01

This paper presents a meta-analysis of existing research related to the economic valuation of the external effects of hydropower. A database consisting of 81 observations derived from 29 studies valuing the non-market impacts of hydropower electricity generation is constructed with the main aim to

Ultra-low energy storage ring at FLAIR

International Nuclear Information System (INIS)

Welsch, Carsten P.; Papash, A. I.; Gorda, O.; Harasimowicz, J.; Karamyshev, O.; Karamysheva, G.; Newton, D.; Panniello, M.; Putignano, M.; Siggel-King, M. R. F.; Smirnov, A.

2012-01-01

The Ultra-low energy electrostatic Storage Ring (USR) at the future Facility for Low-energy Antiproton and Ion Research (FLAIR) will provide cooled beams of antiprotons in the energy range between 300 keV down to 20 keV and possibly less. The USR has been completely redesigned over the past three years. The ring structure is based on a “split achromat” lattice that allows in-ring experiments with internal gas jet target. Beam parameters might be adjusted in a wide range: from very short pulses in the nanosecond regime to a Coasting beam. In addition, a combined fast and slow extraction scheme was developed that allows for providing external experiments with cooled beams of different time structure. Detailed investigations of the USR, including studies into the ring’s long term beam dynamics, life time, equilibrium momentum spread and equilibrium lateral spread during collisions with an internal target were carried out. New tools and beam handling techniques for diagnostics of ultra-low energy ions at beam intensities less than 10 6 were developed by the QUASAR Group. In this paper, progress on the USR project will be presented with an emphasis on the expected beam parameters available to the experiments at FLAIR.

Hydropower developments in Canada: greenhouse gas emissions, energy outputs and review of environmental impacts

Energy Technology Data Exchange (ETDEWEB)

Lee, Peter G.; Cheng, Ryan; Scheelar, Catherine [Global Forest Watch Canada (Canada)

2011-11-15

Hydropower is an important source of energy for Canada, accounting for 60% of the electricity generation mix. It is therefore important to understand the environmental performance of such developments in terms of greenhouse gas emissions and environmental impacts. From study of the Eastmain-1 reservoir, it has been extrapolated that hydropower facilities emit between 20 and 36 kilograms of CO2 per megawatt-hour. Hydropower facilities emissions are thus significantly lower than those of fossil fuel facilities, which can emit up to 1,000 kg of CO2 per MW/h. However, hydro projects have several other environmental impacts, such as habitat degradation, bio-accumulation of methyl mercury, and important sediment flow changes. The 271 large hydropower facilities affect 130,000 km of rivers and tens of thousands square kilometres of adjacent habitat. This study pointed out that despite being a low emitter of carbon dioxide, the hydropower sector has significant environmental impacts which require further assessment.

Mini and micro hydropower systems in India

International Nuclear Information System (INIS)

Kothari, D.P.

1992-01-01

Hydropower is one of the renewable sources of energy. In the field of hydropower, even though small/mini/micro hydropower systems make fractional increases in the overall energy production, their impact on the local areas in which they are sited can be significant in stimulating growth of rural industry and in meeting the basic energy needs of the local population for domestic and agricultural use. They also help in reducing demand on other non-renewable polluting resources like fossil fuels. Moreover as compared to big hydropower systems, small hydropower systems are cost competitive and minimally disruptive to the environment. They require less time for construction and reduce transmission losses. They can be designed to suit the limits of water resources available and can be tailored to the needs of the end-use market. Aspects of small hydropower projects which needs to be studied are listed. Modelling of turbines and generators for such projects, and factors to be considered in selection of suitable turbine and generator for a particular small hydropower system are discussed. The technology for small hydropower systems is well developed and available in India. The present estimated potential of such systems in India is 5000 MW out of which 207 MW is harnessed. These small hydropower plants are mostly located in the northern states like Jammu and Kashmir, Uttar Pradesh, Punjab, and Rajasthan. Construction works for 234 MW at 88 sites are going on. During the 8th plan period, 218.5 MW is planned to be developed with an outlay of Rs. 548.25 crores. It is suggested that special subsidies and liberal term loans should be made available for implementing such systems. (M.G.B.). 8 refs., 2 tabs., 1 fig

Critical evaluation of the hydropower applications in Greece

Energy Technology Data Exchange (ETDEWEB)

Kaldellis, J.K. [Laboratory of Soft Energy Applications and Environmental Protection, TEI Piraeus, P.O. Box 41046, Athens 12201 (Greece)

2008-01-15

Hydropower is a proven technology for electricity generation, contributing with almost 20% to the fulfilment of the planet electricity demand. Hydropower is also renewable because it draws its essential energy from the sun and particularly from the hydrological cycle. Greece and more precisely the west and north part of the mainland possesses significant hydropower potential that is up to now partially exploited. In the present survey, one investigates the existing situation concerning the applications of hydropower plants in Greece, while the results obtained are compared with the corresponding international and European situation. Subsequently, emphasis is laid on estimating the electricity-generation utilization degree of the existing large hydropower stations, using 25-year long official data. The results obtained underline the fact that the electricity generation is not a priority for the national water management policy and most Greek hydropower stations are used mainly to meet the corresponding peak load demand. On the other hand, increased interest to create numerous new small hydropower plants throughout Greece has been expressed during the last 5 years. According to the information gathered and analyzed, one may state that the available local hydropower potential is quite promising and can substantially contribute to the accomplishment of the national-EU target to cover the 21% of the corresponding electricity consumption from renewable resources. For this purpose one should first define an approved and rational water resources management plan and secondly support the increased utilization of large and small hydropower plants for electricity generation. In this case, properly designed hydropower plants should lead to considerable profits, contributing also in the country's independency from imported oil and accomplishing the Kyoto protocol obligations. (author)

Evaluation of economic rent of hydropower projects

International Nuclear Information System (INIS)

Shrestha, Ram M.; Abeygunawardana, A.M.A.K.

2009-01-01

Existing studies have mostly estimated the ex post economic rent of hydropower for the hydroelectric system of a province or a country as a whole and have ignored the site- or project-specific variations in the economic rent of hydropower plants. Further, most of the existing studies have used simplified methods to calculate the rent ex post. This paper presents a rigorous methodology for estimation of site-specific (i.e., project specific) economic rent of hydropower ex ante. It applies the methodology in the case of a hydropower project and analyzes the sensitivity of the rent to variations in some key parameters.

Advanced Technology for Ultra-Low Power System-on-Chip (SoC)

Science.gov (United States)

2017-06-01

was proposed for lower power applications with Ioff=10pA/μm and VDD=0.5V. In this project, the optimized structure shows great potential in both Lg...AFRL-RY-WP-TR-2017-0115 ADVANCED TECHNOLOGY FOR ULTRA-LOW POWER SYSTEM-ON-CHIP (SoC) Jason Woo, Weicong Li, and Peng Lu University of California...September 2015 – 31 March 2017 4. TITLE AND SUBTITLE ADVANCED TECHNOLOGY FOR ULTRA-LOW POWER SYSTEM-ON- CHIP (SoC) 5a. CONTRACT NUMBER FA8650-15-1-7574 5b

Hydro-power: a long history, a bright future

Energy Technology Data Exchange (ETDEWEB)

Deudney, D

1981-07-01

A brief history of the spread of hydro-power in the world was given. Tables showing hydro-power potential and use, and the % electricity from hydro-power for 13 countries were included along with a graph showing % hydro-power operating, planned and under construction by region. The need for committed and farsighted political leadership for future development and the possibility of hydro production reaching 4 to 6 times its present level were discussed.

Physics with ultra-low energy antiprotons

International Nuclear Information System (INIS)

Holtkamp, D.B.; Holzscheiter, M.H.; Hughes, R.J.

1989-01-01

The experimental observation that all forms of matter experience the same gravitational acceleration is embodied in the weak equivalence principle of gravitational physics. However no experiment has tested this principle for particles of antimatter such as the antiproton or the antihydrogen atom. Clearly the question of whether antimatter is in compliance with weak equivalence is a fundamental experimental issue, which can best be addressed at an ultra-low energy antiproton facility. This paper addresses the issue. 20 refs

Ultra-Low-Dropout Linear Regulator

Science.gov (United States)

Thornton, Trevor; Lepkowski, William; Wilk, Seth

2011-01-01

A radiation-tolerant, ultra-low-dropout linear regulator can operate between -150 and 150 C. Prototype components were demonstrated to be performing well after a total ionizing dose of 1 Mrad (Si). Unlike existing components, the linear regulator developed during this activity is unconditionally stable over all operating regimes without the need for an external compensation capacitor. The absence of an external capacitor reduces overall system mass/volume, increases reliability, and lowers cost. Linear regulators generate a precisely controlled voltage for electronic circuits regardless of fluctuations in the load current that the circuit draws from the regulator.

Hearing loss due to concurrent daily low-dose cisplatin chemoradiation for locally advanced head and neck cancer

International Nuclear Information System (INIS)

Zuur, Charlotte L.; Simis, Yvonne J.W.; Verkaik, Roxanna S.; Schornagel, Jan H.; Balm, Alfons J.M.; Dreschler, Wouter A.; Rasch, Coen R.N.

2008-01-01

Background and purpose: Cisplatin-based chemo-irradiation (CRT) is increasingly used for head and neck squamous cell carcinoma (HNSCC). We aimed to assess hearing deterioration due to low-dose cisplatin chemoradiation and to compare the observed hearing loss with hearing loss in our previously described high-dose cisplatin CRT cohort. Materials and methods: A prospective analysis of hearing thresholds at low and (ultra)-high frequencies obtained before and after treatment in 60 patients. Patients received low-dose cisplatin (6 mg/m 2 , daily infusions, 20-25 days) with concomitant accelerated radiotherapy (70 Gy). Results: Audiometry up to 16 kHz was performed before therapy and 31 days (median) post-treatment. The total incidence of ototoxicity in CTCAEv3.0 was 31% in audiograms up to 8 kHz, and 5% of ears tested qualified for HAs due to treatment. The mean hearing loss at speech frequencies was 2.6 dB (SD 5.7) and 2.3 dB (SD 9.2) at PTA 1-2-4 kHz air-conduction and bone-conduction, respectively. The mean hearing loss at ultra-high frequencies (PTA AC 8-10-12.5 kHz) was 9.0 dB (SD 8.1). Low-dose cisplatin CRT caused less acute hearing loss (CTCAE 31%), compared to high-dose cisplatin CRT (CTCAE 78%). Conclusions: Low-dose cisplatin chemo-irradiation for HNSCC is a relatively safe treatment protocol with respect to ototoxicity

Ultra-Low Noise Germanium Neutrino Detection system (ULGeN).

Energy Technology Data Exchange (ETDEWEB)

Cabrera-Palmer, Belkis [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Barton, Paul [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

2017-07-01

Monitoring nuclear power plant operation by measuring the antineutrino flux has become an active research field for safeguards and non-proliferation. We describe various efforts to demonstrate the feasibility of reactor monitoring based on the detection of the Coherent Neutrino Nucleus Scattering (CNNS) process with High Purity Germanium (HPGe) technology. CNNS detection for reactor antineutrino energies requires lowering the electronic noise in low-capacitance kg-scale HPGe detectors below 100 eV as well as stringent reduction in other particle backgrounds. Existing state- of-the-art detectors are limited to an electronic noise of 95 eV-FWHM. In this work, we employed an ultra-low capacitance point-contact detector with a commercial integrated circuit preamplifier- on-a-chip in an ultra-low vibration mechanically cooled cryostat to achieve an electronic noise of 39 eV-FWHM at 43 K. We also present the results of a background measurement campaign at the Spallation Neutron Source to select the area with sufficient low background to allow a successful first-time measurement of the CNNS process.

Ultra-Low Noise Germanium Neutrino Detection system (ULGeN)

International Nuclear Information System (INIS)

Cabrera-Palmer, Belkis; Barton, Paul

2017-01-01

Monitoring nuclear power plant operation by measuring the antineutrino flux has become an active research field for safeguards and non-proliferation. We describe various efforts to demonstrate the feasibility of reactor monitoring based on the detection of the Coherent Neutrino Nucleus Scattering (CNNS) process with High Purity Germanium (HPGe) technology. CNNS detection for reactor antineutrino energies requires lowering the electronic noise in low-capacitance kg-scale HPGe detectors below 100 eV as well as stringent reduction in other particle backgrounds. Existing state- of-the-art detectors are limited to an electronic noise of 95 eV-FWHM. In this work, we employed an ultra-low capacitance point-contact detector with a commercial integrated circuit preamplifier- on-a-chip in an ultra-low vibration mechanically cooled cryostat to achieve an electronic noise of 39 eV-FWHM at 43 K. We also present the results of a background measurement campaign at the Spallation Neutron Source to select the area with sufficient low background to allow a successful first-time measurement of the CNNS process.

Climate Risk in Southern and Eastern Africa's Hydropower Generation

Science.gov (United States)

Dalin, C.; Conway, D.; Landman, W.; Osborn, T.

2016-12-01

Hydropower comprises a major proportion of electricity production in southern and eastern Africa and is undergoing rapid expansion. Hydropower production in both regions is exposed to high levels of climate variability and regional linkages are strong, yet an understanding of aggregate climate risk is lacking. Here we map regions of coherent precipitation variability with current and planned (2030) hydropower sites, river basin configuration and regional energy grids to assess aggregate exposure to hydropower supply disruption. If fully implemented hydropower will be increasingly concentrated in the Nile basin in eastern Africa and the Zambezi basin in southern Africa. Regions of similar rainfall variability show close alignment with the main sites of hydropower. Future concentration of hydropower will greatly increase the concurrent risk of climate related electricity supply disruption. Nascent electricity sharing mechanisms could mitigate risk but face considerable political and infrastructural challenges.

Hydropower engineering. Paper no. IGEC-1-005

International Nuclear Information System (INIS)

Cervantes, M.

2005-01-01

Hydropower, one of the corner stones of sustainable energy development, is the largest renewable source of energy. There is a large demand worldwide for people trained to design, operate, maintain and optimise hydropower systems. Hydro Power University, a name which encompasses both education, research and development within hydropower in Sweden, offers a unique and broad international masters programme within hydropower engineering including civil, mechanical and electrical engineering. The programme is the result of a close collaboration between Lulea University of Technology and Uppsala University, at the research and education level. This master programme, Hydropower Engineering, is open to both Swedish and foreign students free of charge. It aims to provide students with state of the art knowledge and experience on parts of the hydropower system such as turbine technology, generator design, rotor dynamics, tribology, dams/dam safety, maintenance and operation and environmental aspects. World unique laboratory experiments are offered to the students at Porjus and Alvkarleby, Sweden. The Porjus Hydropower Centre offers world unique facilities: two full scale turbines of 10 MW each, one with the latest generator technology - Powerformer. The turbines are exclusively dedicated for use in education, research and development. State of the art in measurement technology is available. Both units are at the centre of each education programme offered by the Hydro Power University. In Alvkarleby, spillways, discharge capacity and turbines model testing can be undertaken at the Vattenfall laboratory also with state of the art experimental material and highly qualified staff. The large number of applications from developing countries indicates a need of scholarships, which needs to be resolved for the development of hydropower. (author)

Environmental impacts of Ghazi Barotha hydropower project on river Indus and surrounding areas

International Nuclear Information System (INIS)

Soomro, G.A.; Sufi, A.B.

2005-01-01

WAPDA being an esteemed organization of the country is involved in development of Water and Power Sector Projects. Ghazi Barotha Hydropower Project is another huge hydropower generation project in the country after Tarbela. The barrage to feed power channel of Ghazi Barotha Power Station are built over River Indus 7 Km down of Tarbela Dam. The project has been constructed to utilize the hydraulic head for power generation that is available between the tailrace of Tarbela Dam and the confluence of Haro River. In this reach river Indus drops by 76 m in distance of 63 Km. This is solely a power generation project with an installed capacity of 1450 MW. The purpose of this paper is to assess the negative impacts on the River Indus due to the construction of GBHP as Water of river Indus will be diverted to the power channel and the river Indus flows go to its lowest in low flow season. The reduction in river flow may change the ecology of the river - belas and people dependant on river water. In this context a study was made to keep the negative environmental impacts as low as possible and suggest mitigation measures to reduce negative impacts and provide enhancement measure to compensate the losses to be sustained by the area people and maintain the social life along with the ecology of the area less disturbed. The study demonstrated that the project is technically sound, economically viable and has limited environmental and social impacts on the area overall and specific the belas and people dependant on the Indus Water from Tarbela downstream up to confluence of Kabul River. (author)

Ultra-low-angle boundary networks within recrystallizing grains

DEFF Research Database (Denmark)

Ahl, Sonja Rosenlund; Simons, Hugh; Zhang, Yubin

2017-01-01

We present direct evidence of a network of well-defined ultra-low-angle boundaries in bulk recrystallizing grains of 99.5% pure aluminium (AA1050) by means of a new, three-dimensional X-ray mapping technique; dark-field X-ray microscopy. These boundaries separate lattice orientation differences o...

Implications of the sedimentation phenomenon in the design of hydropower reservoirs

International Nuclear Information System (INIS)

Scvortov, Felix; Armencea, Gheorghe

1992-01-01

The influence of sedimentation phenomena on the operational parameters of the hydropower reservoirs built on several Romanian rivers was assessed. A cascade of eight reservoirs on the Olt river, with initial volumes of 20-50 M m 3 , lost about 30% of the conservation capacity and about 3-7% of head as well. Smaller reservoirs, with volumes of 2-10 M m 3 , lost 60-85% of their capacity. Dredging operations had to be done, thus, increasing the initial costs by 20%. The acquired experience revealed that the evolution in time of the reservoir capacity over the operation period should be as accurately as possible taken into account in the designing stage. The operation conditions and designing criterions for small and medium hydropower reservoir have to be reassessed also from the environmental and efficiency points of view. The content of the paper is the following: 1. Sedimentation knowledge and planning concepts for inland rivers; 2. Implications of the sedimentation phenomenon; 3. Forecast of the sedimentation phenomenon; 4. Retrospective and perspective; 5. Conclusions. (authors)

Pumped Storage and Potential Hydropower from Conduits

Energy Technology Data Exchange (ETDEWEB)

none,

2015-02-25

Th is Congressional Report, Pumped Storage Hydropower and Potential Hydropower from Conduits, addresses the technical flexibility that existing pumped storage facilities can provide to support intermittent renewable energy generation. This study considered potential upgrades or retrofit of these facilities, the technical potential of existing and new pumped storage facilities to provide grid reliability benefits, and the range of conduit hydropower opportunities available in the United States.

Health implications of hydropower development

International Nuclear Information System (INIS)

Biswas, A.K.

1982-01-01

Hydropower development had been neglected in many countries during the past few decades, but the situation dramatically changed during the 1970s owing to the constantly increasing costs of electricity generation by fossil-fuel and nuclear power plants. Currently, hydroelectric generation accounts for approximately 23% of total global electricity supply. Much of the hydropower potential in developing countries of Africa, Asia and Latin America still remains to be exploited. Like any other source of energy, hydropower development has several health impacts. Conceptually, health implications of hydropower development can be divided into two broad categories: short-term and long-term problems. Short-term health impacts occur during the planning, construction and immediate post-construction phases, whereas long-term impacts stem from the presence of large man-made lakes, development of extensive canal systems, alteration of the ecosystem of the area, and changing socio-economic conditions. Longer-term impacts are further classified into two categories: introduction of new diseases and/or intensification of existing ones due to the improvements of the habitats of disease-carrying vectors, and health problems arising from resettlement of the people whose homes and land-holdings are inundated by the reservoirs. All these impacts are discussed in detail. Health impacts of hydropower developments have not yet been studied extensively. It is often implicitly assumed that health impacts of major dams are minor compared with other social and environmental impacts. Future studies could possibly reverse this assumption. (author)

Ultra-low Temperature Curable Conductive Silver Adhesive with different Resin Matrix

Science.gov (United States)

Zhou, Xingli; Wang, Likun; Liao, Qingwei; Yan, Chao; Li, Xing; Qin, Lei

2018-03-01

The ultra-low temperature curable conductive silver adhesive with curing temperature less than 100 °C needed urgently for the surface conductive treatment of piezoelectric composite material due to the low thermal resistance of composite material and low adhesion strength of adhesive. An ultra-low temperature curable conductive adhesive with high adhesion strength was obtained for the applications of piezoelectric composite material. The microstructure, conductive properties and adhesive properties with different resin matrix were investigated. The conductive adhesive with AG-80 as the resin matrix has the shorter curing time (20min), lower curing temperature (90°C) and higher adhesion strength (7.6MPa). The resistivity of AG-80 sample has the lower value (2.13 × 10-4Ω·cm) than the 618 sample (4.44 × 10-4Ω·cm).

Ultra-Low Voltage Class AB Switched Current Memory Cell

DEFF Research Database (Denmark)

Igor, Mucha

1996-01-01

This paper presents the theoretical basis for the design of class AB switched current memory cells employing floating-gate MOS transistors, suitable for ultra-low-voltage applications. To support the theoretical assumptions circuits based on these cells were designed using a CMOS process with thr......This paper presents the theoretical basis for the design of class AB switched current memory cells employing floating-gate MOS transistors, suitable for ultra-low-voltage applications. To support the theoretical assumptions circuits based on these cells were designed using a CMOS process...... with threshold voltages of 0.9V. Both hand calculations and PSPICE simulations showed that the cells designed allowed a maximum signal range better than +/-13 micoamp, with a supply voltage down to 1V and a quiescent bias current of 1 microamp, resulting in a very high current efficiency and effective power...

Risk management of hydropower development in China

International Nuclear Information System (INIS)

Tang, Wenzhe; Li, Zhuoyu; Qiang, Maoshan; Wang, Shuli; Lu, Youmei

2013-01-01

There is a rapidly increasing demand for hydropower in China. However, little research has been conducted to systematically investigate the overall aspects of hydropower development risks. With support of the data collected from a fieldwork survey, this study reports the multiple facets of hydropower development risks in China as perceived by main project participants. All groups have a common view on the criticality of safety, and the groups also have their own priorities, i.e., resettlement of migrants, incompetence of subcontractors, project delay, inadequate or incorrect design, premature failure of facilities and ecological and environmental impacts are the key risks to clients, whereas quality of work, financial related risks, reputation, and claims and disputes are the main concerns to contractors. A case study of Three Gorges Project further demonstrates that, hydropower development risks can be effectively managed by encouraging joint efforts of all participants to achieve the goals on producing renewable energy, reducing emissions of CO 2 , and providing important social/economical benefits. Future hydropower development should emphasize the interactions between project delivery, environmental, and economical processes to reach appropriate trade-offs among involving stakeholders, by adequately considering the inter-relations between project participants' risks as well as hydropower project's externalities on a broad view. - Highlights: • Largely attributed to unforeseen geology conditions, safety is critical in hydropower development. • Resettlement of migrants is the principal risk to clients, whereas quality of works is the first concern to contractors. • One group's risks are typically related to others', needing collaborative risk management by participants. • Three Gorges Project plays a key role on producing renewable energy, and providing social/economical benefits. • Hydropower development should emphasize the interactions between

Estimation of the cost of electro-mechanical equipment for small hydropower plants – review and comparison of methods

Directory of Open Access Journals (Sweden)

Lipiński Seweryn

2017-01-01

Full Text Available The estimate of the cost of electro-mechanical equipment for new small hydropower plants most often amounts to about 30-40% of the total budget. In case of modernization of existing installations, this estimation represents the main cost. This matter constitutes a research problem for at least few decades. Many models have been developed for that purpose. The aim of our work was to collect and analyse formulas that allow estimation of the cost of investment in electro-mechanical equipment for small hydropower plants. Over a dozen functions were analysed. To achieve the aim of our work, these functions were converted into the form allowing their comparison. Then the costs were simulated with respect to plants’ powers and net heads; such approach is novel and allows deeper discussion of the problem, as well as drawing broader conclusions. The following conclusions can be drawn: significant differences in results obtained by using various formulas were observed; there is a need for a wide study based on national investments in small hydropower plants that would allow to develop equations based on local data; the obtained formulas would let to determinate the costs of modernization or a new construction of small hydropower plant more precisely; special attention should be payed to formulas considering turbine type.

A future role for cascade hydropower in the electricity system of China

International Nuclear Information System (INIS)

Tang, Xinhua; Zhou, Jianjun

2012-01-01

Due to the dominance of coal power, the electricity sector is the primary contributor of greenhouse gas emissions in China. The increase of peak-load and intermittent renewable power requires significant resources of regulation facilities. Comprehensively utilizing large-scale cascade hydropower plants (CHPPs), which are being rapidly developed in China, as renewable regulating facilities would be a strategic decision, considering the flexibility of hydropower. Jointly modeling a set of CHPP in the upstream Yangtze River indicated that the CHPP can regulate peak-load up to 30–40 GW and intermittent renewables to scales of nearly 15 GW from wind and solar sources with the help of ±800 KV ultra-high voltage direct current (UHVDC) transmissions. The present study shows that the hydraulic stability of the concerned river reaches can be preserved easily and the comprehensive efficiency of regulation and transmission by CHPPs is much higher than that of pumped hydro energy storage (PHES) stations. As increasingly more giant CHPPs emerge in west China, using them primarily as regulating facilities can enhance the structure of power grids, promote the development of renewables, save energy and reduce emissions. Thus we propose to shift the CHPPs that were originally projected mainly for electricity to facility primarily for power improvement. - Highlights: ► Large cascade hydropower plant (CHPP) is efficient and renewable peaking facility (PF). ► CHPPs can easily anti-regulate the hydro-fluctuations caused by power regulations. ► Remote CHPPs with UHVDC transmission can massively replace the traditional PFs.► Shift China's CHPPs mainly as PF to promote intermittent renewables are proposed.

Norwegian hydropower a valuable peak power source

Energy Technology Data Exchange (ETDEWEB)

Brekke, Hermod

2010-07-01

Full text: The paper gives a historical technical review of the development and installation of approximately 20 000 MW of hydraulic turbines in Norway after World War II. The non polluting production of electricity was consumed for lightening and heating for civil consume and the growing electric furnace industry in Norway in addition to export in rainy years. The paper is mainly based on the authors experience in the design of large turbines, and control systems for operation of Francis Turbines and Reversible Pump Turbines for high and medium heads and Pelton turbines for high heads. During the last 15 years the development of small hydro power plants has also given an increasing contribution to the power production. A brief discussion will be given on the choice of equipment for small hydro production with a very small winter production and overload during the summer. The possibility of operation of a small hydropower plants connected to an isolated grid will also briefly be presented. In addition to the general design of turbines and control systems for large hydro plants, a detailed description will be given of the stability analysis for the governing system which was developed for the large high head plants with long high pressure tunnels systems. A discussion will be included on the introduction of the air cushioned surge chambers for fast stable operation of power plants with long tunnels, connected to isolated grids. Also the principle of stabilizing unstable turbine governing system by means of pressure feed back systems, will be presented and discussed. A description of such system developed in 1992, will be given proving that stability could be obtained in a system with long conduits connected to the turbines. However, the 'governing speed' needed for isolated operation could not be fulfilled without a fast by pass pressure relieve system for Francis turbines, which was not installed in the case for the analysis. Finally a discussion will be

Ultra low and negative expansion glass–ceramic materials ...

Indian Academy of Sciences (India)

Ultra low and negative expansion glass–ceramic materials have been obtained from pyrophyllite and blast furnace slag. The batch composition was modified with the addition of lithium carbonate, hydrated alumina, boric acid and nucleating agent (titania). The batch was melted at 1400°C followed by casting in the form of ...

Optimal short-term operation schedule of a hydropower plant in a competitive electricity market

International Nuclear Information System (INIS)

Perez-Diaz, Juan I.; Wilhelmi, Jose R.; Arevalo, Luis A.

2010-01-01

This paper presents a dynamic programming model to solve the short-term scheduling problem of a hydropower plant that sells energy in a pool-based electricity market with the objective of maximizing the revenue. This is a nonlinear and non-concave problem subject to strong technical and strategic constraints, and in which discrete and continuous variables take part. The model described in this paper determines, in each hour of the planning horizon (typically from one day to one week), both the optimal number of units in operation (unit commitment) and the power to be generated by the committed units (generation dispatch). The power generated by each unit is considered as a nonlinear function of the actual water discharge and volume of the associated reservoir. The dependence of the units' efficiency and operating limits with the available gross head is also accounted for in this model. The application of this model to a real hydropower plant demonstrates its capabilities in providing the operation schedule that maximizes the revenue of the hydro plant while satisfying several constraints of different classes. In addition, the use of this model as a supporting tool to estimate the economic feasibility of a hydropower plant development project is also analyzed in the paper. (author)

Ultra-low-power short-range radios

CERN Document Server

Chandrakasan, Anantha

2015-01-01

This book explores the design of ultra-low-power radio-frequency integrated circuits (RFICs), with communication distances ranging from a few centimeters to a few meters. Such radios have unique challenges compared to longer-range, higher-powered systems. As a result, many different applications are covered, ranging from body-area networks to transcutaneous implant communications and Internet-of-Things devices. A mix of introductory and cutting-edge design techniques and architectures which facilitate each of these applications are discussed in detail. Specifically, this book covers:.

75 FR 16456 - Inglis Hydropower, LLC; Notice Soliciting Scoping Comments

Science.gov (United States)

2010-04-01

... Hydropower, LLC; Notice Soliciting Scoping Comments March 26, 2010. Take notice that the following...: Inglis Hydropower, LLC. e. Name of Project: Inglis Hydropower Project. f. Location: The proposed project... Commission staff intends to prepare a single Environmental Assessment (EA) for the Inglis Hydropower Project...

A University Consortium on Low Temperature Combustion for High Efficiency, Ultra-Low Emission Engines

Energy Technology Data Exchange (ETDEWEB)

Assanis, Dennis N. [Univ. of Michigan, Ann Arbor, MI (United States); Atreya, Arvind [Univ. of Michigan, Ann Arbor, MI (United States); Chen, Jyh-Yuan [Univ. of California, Berkeley, CA (United States); Cheng, Wai K. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Dibble, Robert W. [Univ. of California, Berkeley, CA (United States); Edwards, Chris [Stanford Univ., CA (United States); Filipi, Zoran S. [Univ. of Michigan, Ann Arbor, MI (United States); Gerdes, Christian [Stanford Univ., CA (United States); Im, Hong [Univ. of Michigan, Ann Arbor, MI (United States); Lavoie, George A. [Univ. of Michigan, Ann Arbor, MI (United States); Wooldridge, Margaret S. [Univ. of Michigan, Ann Arbor, MI (United States)

2009-12-31

The objective of the University consortium was to investigate the fundamental processes that determine the practical boundaries of Low Temperature Combustion (LTC) engines and develop methods to extend those boundaries to improve the fuel economy of these engines, while operating with ultra low emissions. This work involved studies of thermal effects, thermal transients and engine management, internal mixing and stratification, and direct injection strategies for affecting combustion stability. This work also examined spark-assisted Homogenous Charge Compression Ignition (HCCI) and exhaust after-treatment so as to extend the range and maximize the benefit of Homogenous Charge Compression Ignition (HCCI)/ Partially Premixed Compression Ignition (PPCI) operation. In summary the overall goals were; Investigate the fundamental processes that determine the practical boundaries of Low Temperature Combustion (LTC) engines; Develop methods to extend LTC boundaries to improve the fuel economy of HCCI engines fueled on gasoline and alternative blends, while operating with ultra low emissions; and Investigate alternate fuels, ignition and after-treatment for LTC and Partially Premixed compression Ignition (PPCI) engines.

The development of an ultra-low-emission gas-fired cyclonic combustor

International Nuclear Information System (INIS)

Xiong, Tian-yu; Khinkis, M.J.; Coppin, W.P.

1991-01-01

A gas-fired cyclonic combustor has been developed for relatively low-temperature direct-air heating applications that require ultra-low pollutant emissions. High-lean premixed combustion with a flame stabilizer is adopted to achieve ultra-low emissions and high turndown operation. On the basis of analytical studies and cold modeling, a 350-kW test combustor was designed and successfully tested. Experimental results obtained using natural gas and ambient air demonstrated that the test combustor can operate steadily at high excess air up to 80% to 100% over a large turndown range up to 40:1. At design operating conditions, NO x emissions as low as 0.6 vppm and CO and total hydrocarbon (THC) emissions below 3 vppm were achieved. Over the full operating range, NO x emissions from 0.3 to 1.0 vppm and CO and THC emissions below 4 vppm were demonstrated. In all tests, concentrations of NO 2 were less than 40% of the total NO x emissions -- lower than the level of NO 2 emissions from combustion processes required for good indoor air quality (0.5 vppm). This paper presents the concept of high-lean premixed ultra-low-emission cyclonic combustion, design specifications for the combustion system, and the major experimental results, including flame stability, emissions, and turndown performance. 13 refs., 12 figs., 1 tab

Resource and utilization of Estonian hydropower

International Nuclear Information System (INIS)

Raesaar, P.

2005-01-01

An overview of the Estonian hydropower resources and their utilization at present as well as prospective for the future are presented in this paper. A short overview of advantages of small hydropower stations and related issues is given. Some technological aspects are treated briefly. (authors)

Experiences of ultra-low-crud high-nickel control in Onagawa nuclear power station

International Nuclear Information System (INIS)

Saito, M.; Goto, Y.; Shinomiya, T.; Sato, M.; Yamazaki, K.; Hirasawa, H.; Yotsuyanagi, T.

2002-01-01

We have adopted various countermeasures for worker dose reduction to plants in Onagawa Nuclear Power Station. ''Ni/Fe ratio control'' has been adopted to Unit 1, and ''ultra-low-crud high-nickel control'' has been adopted to Unit 2 and 3, along with other countermeasures like wide utilization of low Co materials, for the purpose of dose rate reduction of primary recirculation piping which is thought to be one of the main exposure sources. In this paper, we describe, first, the reason and background that ultra-low-crud high-nickel control has been adopted to Unit 2, and, second, water chemistry of Unit 2 up to the 5. cycle under ultra-low-crud high-nickel control compared to that of Unit 1 under Ni/Fe ratio control. Following those, we show brief analysis of the fuel crud of Unit 2 and water chemistry of Unit 3 only at the startup stage. (authors)

A model of the environmental impacts of hydropower projects

International Nuclear Information System (INIS)

Kemppainen, T.; Haemaelaeinen, I.

1992-01-01

The aim was to create a model of the effects of hydropower modernization and extension projects in Finland. To illustrate the effects of hydropower projects a checklist in the form of matrice was constructed. In this matrice all issues that could be significant in future hydropower projects were collected. Stable physical environmental changes are the starting-point for this matrice. The temporary change of hydropower constructions have also been under consideration. These are mainly environmental changes during construction. In chapter two the effects of hydropower modernization and extension projects physical environmental changes were examined. In chapter three the matrice was applied to some example cases. The cases were chosen to represent future hydropower projects. In addition these example cases represent urban areas, rural areas and uninhabited areas. The example cases were the extension of Tainionkoski hydropower plant at Vuoksi river, the modernization of Aeetsae power plant at Kokemaeenjoki river, the modernization of Stadsfors power plant at Lapuanjoki river in the centre of Uusikaarlepyy town and the construction of Kaitfors power plant at Perhonjoki river. Conclusions from usability of the model can be drawn on the ground of the example cases. The purpose of the model is to produce a checklist of estimated environmental effects in hydropower project of various kinds. Examination of issues within the model depends on local circumstances. Endangered animal and plant species, for example, can be studied and estimated only if endangered animal and plant species exist in the area of hydropower plant. Furthermore, the direction and extent of environmental effects depend on the local circumstances. The model is mainly a checklist of environmental effects caused by hydropower plant projects

Willingness to pay for environmental improvements in hydropower regulated rivers

International Nuclear Information System (INIS)

Kataria, Mitesh

2009-01-01

This paper uses a choice experiment to estimate how Swedish households value different environmental improvements for the hydropower regulated rivers. We obtained clear evidence that Swedish households have preferences for environmental improvement in hydropower regulated waters, at least when the cost is relatively low. Remedial measures that improve the conditions for all of the included environmental attributes i.e. fish, benthic invertebrates, river-margin vegetation and birds were found to have a significant welfare increasing impact. The results can be of value for the implementation of the Water Framework Directives in Sweden, which aims to reform the use of all surface water and ground water in the member states. (author)

Gis-based procedures for hydropower potential spotting

Energy Technology Data Exchange (ETDEWEB)

Larentis, Dante G.; Collischonn, Walter; Tucci, Carlos E.M. [Instituto de Pesquisas Hidraulicas da UFRGS, Av. Bento Goncalves, 9500, CEP 91501-970, Caixa Postal 15029, Porto Alegre, RS (Brazil); Olivera, Francisco (Texas A and M University, Zachry Department of Civil Engineering 3136 TAMU, College Station, TX 77843-3136, US)

2010-10-15

The increasing demand for energy, especially from renewable and sustainable sources, spurs the development of small hydropower plants and encourages investment in new survey studies. Preliminary hydropower survey studies usually carry huge uncertainties about the technical, economic and environmental feasibility of the undeveloped potential. This paper presents a methodology for large-scale survey of hydropower potential sites to be applied in the inception phase of hydroelectric development planning. The sequence of procedures to identify hydropower sites is based on remote sensing and regional streamflow data and was automated within a GIS-based computational program: Hydrospot. The program allows spotting more potential sites along the drainage network than it would be possible in a traditional survey study, providing different types of dam-powerhouse layouts and two types (operating modes) of projects: run-of-the-river and storage projects. Preliminary results from its applications in a hydropower-developed basin in Brazil have shown Hydrospot's limitations and potentialities in giving support to the mid-to-long-term planning of the electricity sector. (author)

A programmable ultra-low noise X-band exciter.

Science.gov (United States)

MacMullen, A; Hoover, L R; Justice, R D; Callahan, B S

2001-07-01

A programmable ultra-low noise X-band exciter has been developed using commercial off-the-shelf components. Its phase noise is more than 10 dB below the best available microwave synthesizers. It covers a 7% frequency band with 0.1-Hz resolution. The X-band output at +23 dBm is a combination of signals from an X-band sapphire-loaded cavity oscillator (SLCO), a low noise UHF frequency synthesizer, and special-purpose frequency translation and up-conversion circuitry.

Ultra-low loss nano-taper coupler for Silicon-on-Insulator ridge waveguide

DEFF Research Database (Denmark)

Pu, Minhao; Liu, Liu; Ou, Haiyan

2010-01-01

A nano-taper coupler is optimized specially for the transverse-magnetic mode for interfacing light between a silicon-on-insulator ridge waveguide and a single-mode fiber. An ultra-low coupling loss of ~0.36dB is achieved for the nano-taper coupler.......A nano-taper coupler is optimized specially for the transverse-magnetic mode for interfacing light between a silicon-on-insulator ridge waveguide and a single-mode fiber. An ultra-low coupling loss of ~0.36dB is achieved for the nano-taper coupler....

Ultra-low friction and excellent elastic recovery of fullerene-like ...

Indian Academy of Sciences (India)

2017-08-24

Aug 24, 2017 ... a high elastic recovery (∼90%), ultra-low friction coefficient (∼0.019) and low wear rate ... Y Meng et al .... [3] Liu D G, Tu J P, Gu C D, Hong C F, Chen R and Yang W S ... [7] Cumings J and Zettl A 2000 Science 289 602.

China’s rising hydropower demand challenges water sector

Science.gov (United States)

Liu, Junguo; Zhao, Dandan; Gerbens-Leenes, P. W.; Guan, Dabo

2015-01-01

Demand for hydropower is increasing, yet the water footprints (WFs) of reservoirs and hydropower, and their contributions to water scarcity, are poorly understood. Here, we calculate reservoir WFs (freshwater that evaporates from reservoirs) and hydropower WFs (the WF of hydroelectricity) in China based on data from 875 representative reservoirs (209 with power plants). In 2010, the reservoir WF totaled 27.9 × 109 m3 (Gm3), or 22% of China’s total water consumption. Ignoring the reservoir WF seriously underestimates human water appropriation. The reservoir WF associated with industrial, domestic and agricultural WFs caused water scarcity in 6 of the 10 major Chinese river basins from 2 to 12 months annually. The hydropower WF was 6.6 Gm3 yr−1 or 3.6 m3 of water to produce a GJ (109 J) of electricity. Hydropower is a water intensive energy carrier. As a response to global climate change, the Chinese government has promoted a further increase in hydropower energy by 70% by 2020 compared to 2012. This energy policy imposes pressure on available freshwater resources and increases water scarcity. The water-energy nexus requires strategic and coordinated implementations of hydropower development among geographical regions, as well as trade-off analysis between rising energy demand and water use sustainability. PMID:26158871

Optimizing Parameters of Axial Pressure-Compounded Ultra-Low Power Impulse Turbines at Preliminary Design

Science.gov (United States)

Kalabukhov, D. S.; Radko, V. M.; Grigoriev, V. A.

2018-01-01

Ultra-low power turbine drives are used as energy sources in auxiliary power systems, energy units, terrestrial, marine, air and space transport within the confines of shaft power N td = 0.01…10 kW. In this paper we propose a new approach to the development of surrogate models for evaluating the integrated efficiency of multistage ultra-low power impulse turbine with pressure stages. This method is based on the use of existing mathematical models of ultra-low power turbine stage efficiency and mass. It has been used in a method for selecting the rational parameters of two-stage axial ultra-low power turbine. The article describes the basic features of an algorithm for two-stage turbine parameters optimization and for efficiency criteria evaluating. Pledged mathematical models are intended for use at the preliminary design of turbine drive. The optimization method was tested at preliminary design of an air starter turbine. Validation was carried out by comparing the results of optimization calculations and numerical gas-dynamic simulation in the Ansys CFX package. The results indicate a sufficient accuracy of used surrogate models for axial two-stage turbine parameters selection

The role of hydropower in environment ally sustainable energy development

International Nuclear Information System (INIS)

Gabriel, H.F.

2005-01-01

Hydropower has historically been the renewable energy leader, and from a technical-cost perspective, is very likely to remain the only viable renewable energy source for many countries. In recent years, hydropower has been much maligned, especially by NGOs, for not being a sustainable source of energy. Though hydropower is clearly a renewable source of energy, but the question arises whether it can also be sustainable. Hydropower can play an increasingly important role in enabling communities around the world to meet sustainability objectives. To become more accepted as a key contributor to sustainable energy systems, new and existing hydropower projects need to be built and operated in an environmentally, socially and economically sustainable manner. This paper highlights the sustain ability aspects of hydropower and discusses the criteria for selection of environmentally friendly hydropower project sites so that that hydropower can be developed in a sustainable manner and once again be considered favorably in the planning of generation mix for new energy development. Sustainability of hydropower projects involves treating both the social and environmental sustainability of the project at an early stage and including the interests of all stakeholders of the project. As a case study, the Ghazi- Barotha Hydropower Project (GBHP) in Pakistan has been selected, as it is the best example in managing the social issues and gaining public acceptance because of proper planning and addressing environmental and social issues at an early stage. (author)

A feasibility and implementation model of small-scale hydropower ...

African Journals Online (AJOL)

Large numbers of households and communities will not be connected to the national electricity grid for the foreseeable future due to high cost of transmission and distribution systems to remote communities and the relatively low electricity demand within rural communities. Small-scale hydropower used to play a very ...

Oxidation of ultra low carbon and silicon bearing steels

Energy Technology Data Exchange (ETDEWEB)

Suarez, Lucia [CTM - Technologic Centre, Materials Technology Area, Manresa, Barcelona (Spain)], E-mail: lucia.suarez@ctm.com.es; Rodriguez-Calvillo, Pablo [CTM - Technologic Centre, Materials Technology Area, Manresa, Barcelona (Spain)], E-mail: pablo.rodriguez@ctm.com.es; Houbaert, Yvan [Department of Materials Science and Engineering, University of Ghent (Belgium)], E-mail: Yvan.Houbaert@UGent.be; Colas, Rafael [Facultad de Ingenieria Mecanica y Electrica, Universidad Autonoma de Nuevo Leon (Mexico)], E-mail: rcolas@mail.uanl.mx

2010-06-15

Oxidation tests were carried out in samples from an ultra low carbon and two silicon bearing steels to determine the distribution and morphology of the oxide species present. The ultra low carbon steel was oxidized for short periods of time within a chamber designed to obtain thin oxide layers by controlling the atmosphere, and for longer times in an electric furnace; the silicon steels were reheated only in the electric furnace. The chamber was constructed to study the behaviour encountered during the short period of time between descaling and rolling in modern continuous mills. It was found that the oxide layers formed on the samples reheated in the electric furnace were made of different oxide species. The specimens treated in the chamber had layers made almost exclusively of wustite. Selected oxide samples were studied by scanning electron microscopy to obtain electron backscattered diffraction patterns, which were used to identify the oxide species in the layer.

Role of hydropower development for improving energy mix with reference to India

Energy Technology Data Exchange (ETDEWEB)

Jose, P.C.

2010-09-15

With more than 70% of the electricity requirement in India being contributed from thermal sources and various issues and problems such as peaking shortage, low PLF operation of many thermal generating stations etc., there is an urgent need to review the prevailing energy mix. Hydropower potential is abundantly available to the tune of about 148,700 MW and more than 75% of which remaining untapped and with all the inherent advantages associated with hydropower, the energy mix can be improved by the development of the balance huge potential.

Projected impacts of climate change on hydropower potential in China

Energy Technology Data Exchange (ETDEWEB)

Liu, Xingcai; Tang, Qiuhong; Voisin, Nathalie; Cui, Huijuan

2016-01-01

Hydropower is an important renewable energy source in China, but it is sensitive to climate change, because the changing climate may alter hydrological conditions (e.g., river flow and reservoir storage). Future changes and associated uncertainties in China's gross hydropower potential (GHP) and developed hydropower potential (DHP) are projected using simulations from eight global hydrological models (GHMs), including a large-scale reservoir regulation model, forced by five general circulation models (GCMs) with climate data under two representative concentration pathways (RCP2.6 and RCP8.5). Results show that the estimation of the present GHP of China is comparable to other studies; overall, the annual GHP is projected to change by −1.7 to 2 % in the near future (2020–2050) and increase by 3 to 6 % in the late 21st century (2070–2099). The annual DHP is projected to change by −2.2 to −5.4 % (0.7–1.7 % of the total installed hydropower capacity (IHC)) and −1.3 to −4 % (0.4–1.3 % of total IHC) for 2020–2050 and 2070–2099, respectively. Regional variations emerge: GHP will increase in northern China but decrease in southern China – mostly in south central China and eastern China – where numerous reservoirs and large IHCs currently are located. The area with the highest GHP in southwest China will have more GHP, while DHP will reduce in the regions with high IHC (e.g., Sichuan and Hubei) in the future. The largest decrease in DHP (in %) will occur in autumn or winter, when streamflow is relatively low and water use is competitive. Large ranges in hydropower estimates across GHMs and GCMs highlight the necessity of using multimodel assessments under climate change conditions. This study prompts the consideration of climate change in planning for hydropower development and operations in China, to be further combined with a socioeconomic analysis for strategic expansion.

Controlling low-rate signal path microdischarge for an ultra-low-background proportional counter

International Nuclear Information System (INIS)

Mace, E.K.; Aalseth, C.E.; Bonicalzi, R.M.; Day, A.R.; Hoppe, E.W.; Keillor, M.E.; Myers, A.W.; Overman, C.T.; Seifert, A.

2013-01-01

Pacific Northwest National Laboratory (PNNL) has developed an ultra-low-background proportional counter (ULBPC) made of high purity copper. These detectors are part of an ultra-low-background counting system (ULBCS) in the newly constructed shallow underground laboratory at PNNL (at a depth of ∼30 m water-equivalent). To control backgrounds, the current preamplifier electronics are located outside the ULBCS shielding. Thus the signal from the detector travels through ∼1 m of cable and is potentially susceptible to high voltage microdischarge and other sources of electronic noise. Based on initial successful tests, commercial cables and connectors were used for this critical signal path. Subsequent testing across different batches of commercial cables and connectors, however, showed unwanted (but still low) rates of microdischarge noise. To control this noise source, two approaches were pursued: first, to carefully validate cables, connectors, and other commercial components in this critical signal path, making modifications where necessary; second, to develop a custom low-noise, low-background preamplifier that can be integrated with the ULBPC and thus remove most commercial components from the critical signal path. This integrated preamplifier approach is based on the Amptek A250 low-noise charge-integrating preamplifier module. The initial microdischarge signals observed are presented and characterized according to the suspected source. Each of the approaches for mitigation is described, and the results from both are compared with each other and with the original performance seen with commercial cables and connectors. (author)

Ultra-low coupling loss fully-etched apodized grating coupler with bonded metal mirror

DEFF Research Database (Denmark)

Ding, Yunhong; Peucheret, Christophe; Ou, Haiyan

2014-01-01

A fully etched apodized grating coupler with bonded metal mirror is designed and demonstrated on the silicon-on-insulator platform, showing an ultra-low coupling loss of only 1.25 dB with 3 dB bandwidth of 69 nm.......A fully etched apodized grating coupler with bonded metal mirror is designed and demonstrated on the silicon-on-insulator platform, showing an ultra-low coupling loss of only 1.25 dB with 3 dB bandwidth of 69 nm....

An estimation of the Swiss hydropower rent

International Nuclear Information System (INIS)

Banfi, Silvia; Filippini, Massimo; Mueller, Adrian

2005-01-01

The electricity generation in Switzerland is mostly based on hydropower (∼58%) and nuclear power (∼38%). The exploitation of water in the hydropower sector can generate significant economic rent. One possibility to capture this rent is through royalties or fees. This system has been used in Switzerland since many decades. However, the actual water fee system is not flexible and does not take into consideration different production costs between the type and location of hydropower plants. Furthermore, storage plants can sell electricity to a higher price than run-of-river plants. A flexible system is needed in a liberalized electricity market, to take into account these different production situations and the fact that prices may vary considerably over time. The main goal of this paper is to calculate the potential economic rent that could be generated in the Swiss hydropower sector under a future liberalized market. Based on the results of the paper, it can be concluded that the introduction of a flexible fee system could improve the competitiveness of the hydropower sector and promote an energy system based on renewable energy sources

Stimulatory and protective effects of alkylating agents applied in ultra-low concentrations.

Science.gov (United States)

Pukhalsky, A L; Shmarina, G V

2001-01-01

Alkylating drugs belonging to the nitrogen mustard family are known as cytostatic and immunosuppressive agents. Ultra-low doses of these drugs may demonstrate pharmacological effects unlike this category of drugs. In the case of a gradual dose decrease, the number of targets for alkylation is also reduced and the drug switches from cytostatic to cell growth modifier. We postulate that application of ultra-low doses of alkylating drugs may result in a beneficial effect in the therapy of diseases associated with chronic inflammation of the mucosa, especially with the signs of epithelial atrophy. Copyright 2001 S. Karger AG, Basel

Conflicting hydropower development and aquatic ecosystem conservation in Bhutan

Science.gov (United States)

Wi, S.; Yang, Y. C. E.

2017-12-01

Hydropower is one of the clean energy sources that many Himalayan countries are eager to develop to solve their domestic energy deficit issue such as India, Nepal and Pakistan. Like other Himalayan countries, Bhutan also has a great potential for hydropower development. However, Bhutan is one of few countries that has a domestic energy surplus and export its hydropower generation to neighboring countries (mainly to India). Exporting hydropower is one of the major economic sources in Bhutan. However, constructions of dams and reservoirs for hydropower development inevitably involve habitat fragmentation, causing a conflict of interest with the pursuit of value in aquatic ecosystem conservation. The objectives of this study is to 1) develop a distributed hydrologic model with snow and glacier module to simulate the hydrologic regimes of seven major watersheds in Bhutan; 2) apply the hydrologic model to compute hydropower generation for all existing and potential dams; 3) evaluate cascade impacts of each individual dam on downstream regions by employing three hydro-ecological indicators: the River Connectivity Index (RCI), Dendritic Connectivity Index (DCI), total affected river stretch (ARS), and 4) analyze the tradeoffs between hydropower generation and river connectivity at the national scale by means of a multiple objective genetic algorithm. Modeling results of three Pareto Fronts between ecological indicators and hydropower generation accompany with future energy export targets from the government can inform dam selections that maximizing hydropower generation while minimizing the impact on the aquatic ecosystem (Figure 1a). The impacts of climate change on these Pareto front are also explored to identify robust dam selection under changing temperature and precipitation (Figure 1b).

Head-Mounted Display Technology for Low Vision Rehabilitation and Vision Enhancement

Science.gov (United States)

Ehrlich, Joshua R.; Ojeda, Lauro V.; Wicker, Donna; Day, Sherry; Howson, Ashley; Lakshminarayanan, Vasudevan; Moroi, Sayoko E.

2017-01-01

Purpose To describe the various types of head-mounted display technology, their optical and human factors considerations, and their potential for use in low vision rehabilitation and vision enhancement. Design Expert perspective. Methods An overview of head-mounted display technology by an interdisciplinary team of experts drawing on key literature in the field. Results Head-mounted display technologies can be classified based on their display type and optical design. See-through displays such as retinal projection devices have the greatest potential for use as low vision aids. Devices vary by their relationship to the user’s eyes, field of view, illumination, resolution, color, stereopsis, effect on head motion and user interface. These optical and human factors considerations are important when selecting head-mounted displays for specific applications and patient groups. Conclusions Head-mounted display technologies may offer advantages over conventional low vision aids. Future research should compare head-mounted displays to commonly prescribed low vision aids in order to compare their effectiveness in addressing the impairments and rehabilitation goals of diverse patient populations. PMID:28048975

Standard Modular Hydropower Technology Acceleration Workshop: Summary Report

Energy Technology Data Exchange (ETDEWEB)

Smith, Brennan T. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); DeNeale, Scott T. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Witt, Adam M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Mobley, Miles H. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Fernandez, Alisha R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2017-08-01

In support of the Department of Energy (DOE) funded Standard Modular Hydropower (SMH) Technology Acceleration project, Oak Ridge National Laboratory (ORNL) staff convened with five small hydropower technology entrepreneurs on June 14 and 15, 2017 to discuss gaps, challenges, and opportunities for small modular hydropower development. The workshop was designed to walk through SMH concepts, discuss the SMH research vision, assess how each participant’s technology aligns with SMH concepts and research, and identify future pathways for mutually beneficial collaboration that leverages ORNL expertise and entrepreneurial industry experience. The goal coming out of the workshop is to advance standardized, scalable, modular hydropower technologies and development approaches with sustained and open dialogue among diverse stakeholder groups.

DOE Hydropower Program Annual Report for FY 2002

Energy Technology Data Exchange (ETDEWEB)

Garold L. Sommers; R. T. Hunt

2003-07-01

The U.S. Department of Energy (DOE) conducts research on advanced hydropower technology through its hydropower program, which is organized under the Office of Wind and Hydropower Technologies within the Office of Energy Efficiency and Renewable Energy. This annual report describes the various projects supported by the hydropower program in FY 2002. The program=s current focus is on improving the environmental performance of hydropower projects by addressing problems such as fish mortality during passage through turbines, alteration of instream habitat, and water quality in tailwaters. A primary goal of this research is to develop new, environmentally friendly technology. DOE-funded projects have produced new conceptual designs for turbine systems, and these are now being tested in pilot-scale laboratory tests and in the field. New design approaches range from totally new turbine runners to modifications of existing designs. Biological design criteria for these new turbines have also been developed in controlled laboratory tests of fish response to physical stresses, such as hydraulic shear and pressure changes. These biocriteria are being combined with computational tools to locate and eliminate areas inside turbine systems that are damaging to fish. Through the combination of laboratory, field, and computational studies, new solutions are being found to environmental problems at hydropower projects. The diverse program activities continue to make unique contributions to clean energy production in the U.S. By working toward technology improvements that can reduce environmental problems, the program is helping to reposition hydropower as an acceptable, renewable, domestic energy choice.

Preamplifier with ultra low frequency cutoff for infrasonic condenser microphone

DEFF Research Database (Denmark)

Kinnerup, Rasmus Trock; Marbjerg, Kresten; Rasmussen, Per

2012-01-01

low frequencies becomes a challenge. The electric preamplifier presented in this paper together with a prepolarized condenser microphone form a measurement system. The developed preamplifier connects the microphone signal directly to the input of an operational amplifier with ultra high input...

Underground Pumped Storage Hydropower using abandoned open pit mines: influence of groundwater seepage on the system efficiency

Science.gov (United States)

Pujades, Estanislao; Bodeux, Sarah; Orban, Philippe; Dassargues, Alain

2016-04-01

Pumped Storage Hydropower (PSH) plants can be used to manage the production of electrical energy according to the demand. These plants allow storing and generating electricity during low and high demand energy periods, respectively. Nevertheless, PSH plants require a determined topography because two reservoirs located at different heights are needed. At sites where PSH plants cannot be constructed due to topography requirements (flat regions), Underground Pumped Storage Hydropower (UPSH) plants can be used to adjust the electricity production. These plants consist in two reservoirs, the upper one is located at the surface (or at shallow depth) while the lower one is underground (or deeper). Abandoned open pit mines can be used as lower reservoirs but these are rarely isolated. As a consequence, UPSH plants will interact with surrounding aquifers exchanging groundwater. Groundwater seepage will modify hydraulic head inside the underground reservoir affecting global efficiency of the UPSH plant. The influence on the plant efficiency caused by the interaction between UPSH plants and aquifers will depend on the aquifer parameters, underground reservoir properties and pumping and injection characteristics. The alteration of the efficiency produced by the groundwater exchanges, which has not been previously considered, is now studied numerically. A set of numerical simulations are performed to establish in terms of efficiency the effects of groundwater exchanges and the optimum conditions to locate an UPSH plant.

Hydropower potential of the lower Vistula

Directory of Open Access Journals (Sweden)

Michał Szydłowski

2015-03-01

Full Text Available This paper presents an estimate analysis of the hydropower potential of the lower Vistula River from Warsaw to Gdańsk Bay. The calculations were made for a hydraulic model of the lower Vistula which takes into account potential development of barrages in a cascade system. Results obtained from the model simulations and from hydrological calculations were used to estimate the power of hydropower plants and the average annual energy output from the entire cascade system. The results of calculations indicate significant energy benefits resulting from the development of a cascade of hydropower plants in the lower Vistula. This study does not discuss the cascade project’s economic viability or other aspects of its development (inland waterways, flood control, etc..

Private equity, public affair: Hydropower financing in the Mekong Basin

NARCIS (Netherlands)

Merme, V.; Ahlers, R.; Gupta, J.

2014-01-01

Large-scale hydropower development is increasingly popular. Although international finance is a significant driver of hydropower market expansion, financial data is relatively obscure and literature remains scarce. This article tracks the financial process in hydropower development in the Mekong

River flow availability for environmental flow allocation downstream of hydropower facilities in the Kafue Basin of Zambia

Science.gov (United States)

Kalumba, Mulenga; Nyirenda, Edwin

2017-12-01

The Government of the Republic Zambia (GRZ) will install a new hydropower station Kafue Gorge Lower downstream of the existing Kafue Gorge Station (KGS) and plans to start operating the Itezhi-Tezhi (ITT) hydropower facility in the Kafue Basin. The Basin has significant biodiversity hot spots such as the Luangwa National park and Kafue Flats. It is described as a Man-Biosphere reserve and the National Park is a designated World Heritage Site hosting a variety of wildlife species. All these natural reserves demand special protection, and environmental flow requirements (e-flows) have been identified as a necessary need to preserve these ecosystems. Implementation of e-flows is therefore a priority as Zambia considers to install more hydropower facilities. However before allocation of e-flows, it is necessary to first assess the river flow available for allocation at existing hydropower stations in the Kafue Basin. The river flow availability in the basin was checked by assessing the variability in low and high flows since the timing, frequency and duration of extreme droughts and floods (caused by low and high flows) are all important hydrological characteristics of a flow regime that affects e-flows. The river flows for a 41 year monthly time series data (1973-2014) were used to extract independent low and high flows using the Water Engineering Time Series Processing Tool (WETSPRO). The low and high flows were used to construct cumulative frequency distribution curves that were compared and analysed to show their variation over a long period. A water balance of each hydropower station was used to check the river flow allocation aspect by comparing the calculated water balance outflow (river flow) with the observed river flow, the hydropower and consumptive water rights downstream of each hydropower station. In drought periods about 50-100 m3/s of riverflow is available or discharged at both ITT and KGS stations while as in extreme flood events about 1300-1500 m3/s

The 'Pontareuse' small hydropower station in Boudry, Switzerland

International Nuclear Information System (INIS)

Hausmann, M.

2007-05-01

This illustrated report for the Swiss Federal Office of Energy (SFOE) describes work done in 2007 on the preliminary project for a small hydropower project to be realised in Boudry, Switzerland. The goal of this project is to take advantage of the hydro power of the river Areuse using an existing artificial weir which has been built and renovated as part of several river corrections in the past. Three variants for the construction of the proposed hydropower installation with a maximum projected power rating of 391 kilowatts are presented in detail. Options for the realisation of a fish pass to enable fish to pass the weir are also discussed. Figures are presented on the financial viability of the project which, although low, could however become interesting when the expected tariff changes in connection with the new Swiss legislation on electrical energy supply are considered

Hydropower's Biogenic Carbon Footprint.

Science.gov (United States)

Scherer, Laura; Pfister, Stephan

2016-01-01

Global warming is accelerating and the world urgently needs a shift to clean and renewable energy. Hydropower is currently the largest renewable source of electricity, but its contribution to climate change mitigation is not yet fully understood. Hydroelectric reservoirs are a source of biogenic greenhouse gases and in individual cases can reach the same emission rates as thermal power plants. Little is known about the severity of their emissions at the global scale. Here we show that the carbon footprint of hydropower is far higher than previously assumed, with a global average of 173 kg CO2 and 2.95 kg CH4 emitted per MWh of electricity produced. This results in a combined average carbon footprint of 273 kg CO2e/MWh when using the global warming potential over a time horizon of 100 years (GWP100). Nonetheless, this is still below that of fossil energy sources without the use of carbon capture and sequestration technologies. We identified the dams most promising for capturing methane for use as alternative energy source. The spread among the ~1500 hydropower plants analysed in this study is large and highlights the importance of case-by-case examinations.

Hydropower's Biogenic Carbon Footprint

Science.gov (United States)

Pfister, Stephan

2016-01-01

Global warming is accelerating and the world urgently needs a shift to clean and renewable energy. Hydropower is currently the largest renewable source of electricity, but its contribution to climate change mitigation is not yet fully understood. Hydroelectric reservoirs are a source of biogenic greenhouse gases and in individual cases can reach the same emission rates as thermal power plants. Little is known about the severity of their emissions at the global scale. Here we show that the carbon footprint of hydropower is far higher than previously assumed, with a global average of 173 kg CO2 and 2.95 kg CH4 emitted per MWh of electricity produced. This results in a combined average carbon footprint of 273 kg CO2e/MWh when using the global warming potential over a time horizon of 100 years (GWP100). Nonetheless, this is still below that of fossil energy sources without the use of carbon capture and sequestration technologies. We identified the dams most promising for capturing methane for use as alternative energy source. The spread among the ~1500 hydropower plants analysed in this study is large and highlights the importance of case-by-case examinations. PMID:27626943

Thayer Lake Hydropower Development -- Final Report

Energy Technology Data Exchange (ETDEWEB)

Matousek, Mark [ORENCO Hydropower, Palo Alto, CA (United States)

2017-06-30

The Thayer Lake Hydropower Development (THLD) has been under study since the late 1970’s as Angoon explored opportunities to provide lower cost renewable power to the Community and avoid the high cost of diesel generation. Kootznoowoo Inc. (Kootznoowoo), the tribal corporation for Angoon’s current and past residents, was provided the rights by Congress to develop a hydropower project within the Admiralty Island National Monument. This grant (DE-EE0002504) by the Department of Energy’s (DOE’s) Office of Indian Energy and a matching grant from the Alaska Energy Authority (AEA) were provided to Kootznoowoo to enable the design, engineering and permitting of this hydropower project on Thayer Creek. Prior to the grant, the USFS had performed a final environmental impact statement (FEIS) and issued a Record of Decision (ROD) in 2009 for a 1.2 MW hydropower project on Thayer Creek that would Angoon’s needs with substantial excess capacity for growth. Kootznoowoo hired Alaska Power & Telephone (AP&T) in 2013 to manage this project and oversee its development. AP&T and its subcontractors under Kootznoowoo’s guidance performed several activities, aligned with the task plan defined in the grant.

Analysis and Research on the effect of the Operation of Small Hydropower in the Regional Power Grid

Science.gov (United States)

Ang, Fu; Guangde, Dong; Xiaojun, Zhu; Ruimiao, Wang; Shengyi, Zhu

2018-03-01

The analysis of reactive power balance and voltage of power network not only affects the system voltage quality, but also affects the economic operation of power grid. In the calculation of reactive power balance and voltage analysis in the past, the problem of low power and low system voltage has been the concern of people. When small hydropower stations in the wet period of low load, the analysis of reactive power surplus and high voltage for the system, if small hydropower unit the capability of running in phase is considered, it can effectively solve the system low operation voltage of the key point on the high side.

The use of public participation and economic appraisal for public involvement in large-scale hydropower projects: Case study of the Nam Theun 2 Hydropower Project

International Nuclear Information System (INIS)

Mirumachi, Naho; Torriti, Jacopo

2012-01-01

Gaining public acceptance is one of the main issues with large-scale low-carbon projects such as hydropower development. It has been recommended by the World Commission on Dams that to gain public acceptance, public involvement is necessary in the decision-making process (). As financially-significant actors in the planning and implementation of large-scale hydropower projects in developing country contexts, the paper examines the ways in which public involvement may be influenced by international financial institutions. Using the case study of the Nam Theun 2 Hydropower Project in Laos, the paper analyses how public involvement facilitated by the Asian Development Bank had a bearing on procedural and distributional justice. The paper analyses the extent of public participation and the assessment of full social and environmental costs of the project in the Cost-Benefit Analysis conducted during the project appraisal stage. It is argued that while efforts were made to involve the public, there were several factors that influenced procedural and distributional justice: the late contribution of the Asian Development Bank in the project appraisal stage; and the issue of non-market values and discount rate to calculate the full social and environmental costs. - Highlights: ► Public acceptance in large-scale hydropower projects is examined. ► Both procedural and distributional justice are important for public acceptance. ► International Financial Institutions can influence the level of public involvement. ► Public involvement benefits consideration of non-market values and discount rates.

The development of an ultra-low-emission gas-fired combustor for space heaters

International Nuclear Information System (INIS)

Xiong, Tian-yu; Khinkis, M.J.; Coppin, W.P.

1991-01-01

An ultra-low-emission as-fired combustor has been developed for relatively low-temperature direct-air heating applications. High-lean premixed cyclonic combustion with a flame stabilizer is employed to achieve ultra-low emissions and high turndown operation. On the basis of analytical studies and cold modeling a 350-kW test combustor was designed and successfully tested. Experimental results obtained using natural gas and ambient air demonstrated that the test combustor can operate steadily at high excess air up to 80% to 100% over a large turndown range up to 40:1. At design operating conditions, NO x emissions as low as 0.6 vppm and CO and total hydrocarbon (THC) emissions below 3 vppm were achieved. Over the full operating range, NO x emissions from 0.3 to 1.0 vppm and CO and THC emissions below 4 vppm were demonstrated. In all tests, concentrations of NO 2 were less than 40% of the total NO 2 emissions from combustion processes required for good indoor air quality (0.5 vppm). This paper presents the concept of high-lean premixed ultra-low-emission cyclonic combustion, design specifications for the combustion system, and the major experimental results, including flame stability, emissions, and turndown performance. 15 refs., 10 figs., 1 tab

A New Ultra-lightweight Authentication Protocol for Low Cost RFID Tags

Directory of Open Access Journals (Sweden)

Xin Wang

2013-05-01

Full Text Available The Radio Frequency Identification (RFID system has been widely used in almost every aspects of the society. At present, the problem of security and privacy become a key factor of severely blocking the widespread of its usage. However, due to restraints on RFID tag’s manufacturing cost, the traditional methods of encryption are not good candidate to defend the security of wireless communication channel between reader and tag. Designing lightweight or ultra-lightweight RFID authentication protocol has become a hot research topic recently. This paper proposes a new ultra-lightweight RFID authentication protocol with high robustness and execution efficiency. The proposed protocol requires only simple bit-wise operations, it has the characteristics of low storage requirement and communication cost. At the same time, through elaborate mechanism design, avoid the vulnerability of the existing ultra-lightweight authentication protocols.

Ultra low nanowear in novel chromium/amorphous chromium carbide nanocomposite films

Science.gov (United States)

Yate, Luis; Martínez-de-Olcoz, Leyre; Esteve, Joan; Lousa, Arturo

2017-10-01

In this work, we report the first observation of novel nanocomposite thin films consisting of nanocrystalline chromium embedded in an amorphous chromium carbide matrix (nc-Cr/a-CrC) with relatively high hardness (∼22,3 GPa) and ultra low nanowear. The films were deposited onto silicon substrates using a magnetic filtered cathodic arc deposition system at various negative bias voltages, from 50 to 450 V. X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) suggested the co-existence of chromium and chromium carbide phases, while high resolution transmission electron microscopy (HRTEM) confirmed the presence of the nc-Cr/a-CrC structure. The friction coefficient measured with the ball-on disk technique and the nanowear results showed a strong correlation between the macro and nano-tribological properties of the samples. These novel nanocomposite films show promising properties as solid lubricant and wear resistant coatings with relatively high hardness, low friction coefficient and ultra low nanowear.

Optimizing Wind And Hydropower Generation Within Realistic Reservoir Operating Policy

Science.gov (United States)

Magee, T. M.; Clement, M. A.; Zagona, E. A.

2012-12-01

Previous studies have evaluated the benefits of utilizing the flexibility of hydropower systems to balance the variability and uncertainty of wind generation. However, previous hydropower and wind coordination studies have simplified non-power constraints on reservoir systems. For example, some studies have only included hydropower constraints on minimum and maximum storage volumes and minimum and maximum plant discharges. The methodology presented here utilizes the pre-emptive linear goal programming optimization solver in RiverWare to model hydropower operations with a set of prioritized policy constraints and objectives based on realistic policies that govern the operation of actual hydropower systems, including licensing constraints, environmental constraints, water management and power objectives. This approach accounts for the fact that not all policy constraints are of equal importance. For example target environmental flow levels may not be satisfied if it would require violating license minimum or maximum storages (pool elevations), but environmental flow constraints will be satisfied before optimizing power generation. Additionally, this work not only models the economic value of energy from the combined hydropower and wind system, it also captures the economic value of ancillary services provided by the hydropower resources. It is recognized that the increased variability and uncertainty inherent with increased wind penetration levels requires an increase in ancillary services. In regions with liberalized markets for ancillary services, a significant portion of hydropower revenue can result from providing ancillary services. Thus, ancillary services should be accounted for when determining the total value of a hydropower system integrated with wind generation. This research shows that the end value of integrated hydropower and wind generation is dependent on a number of factors that can vary by location. Wind factors include wind penetration level

Ultra-low energy electrons from fast heavy-ion helium collisions: the `target Cusp`

Energy Technology Data Exchange (ETDEWEB)

Schmitt, W. [Freiburg Univ. (Germany)]|[Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany); Moshammer, R.; Kollmus, H.; Ullrich, J. [Freiburg Univ. (Germany); O`Rourke, F.S.C. [Queen`s Univ., Belfast, Northern Ireland (United Kingdom); Sarkadi, L. [Magyar Tudomanyos Akademia, Debrecen (Hungary). Atommag Kutato Intezete; Mann, R. [Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany); Hagmann, S. [Kansas State Univ., Manhattan, KS (United States). J.R. MacDonald Lab.; Olson, R.E. [Missouri Univ., Rolla, MO (United States). Dept. of Physics

1998-09-01

Doubly differential cross sections d{sup 2}{sigma}/dv {sub parallel} dv {sub perpendicular} {sub to} have been obtained by mapping the 3-dimensional velocity space of ultra-low and low-energy electrons (1.5 meV{<=} E{sub e}{<=}100 eV) emitted in singly ionizing 3.6 MeV/u Au{sup 53+} on helium collisions. A sharp ({Delta}E{sub e} {sub perpendicular} {sub to} {sup FWHM} {<=} 22 meV) asymmetric peak centered at vertical stroke anti {nu} vertical stroke =0 is observed to emerge at ultra-low energies from the strongly forward shifted low-energy electron velocity distribution. The shape of this ``target cusp``, which is very sensitive on the details of the two-center potential, is in excellent accord with theoretical CTMC and CDW-EIS predictions. (orig.)

Short-term optimal operation of Three-gorge and Gezhouba cascade hydropower stations in non-flood season with operation rules from data mining

International Nuclear Information System (INIS)

Ma Chao; Lian Jijian; Wang Junna

2013-01-01

Highlights: ► Short-term optimal operation of Three-gorge and Gezhouba hydropower stations was studied. ► Key state variable and exact constraints were proposed to improve numerical model. ► Operation rules proposed were applied in population initiation step for faster optimization. ► Culture algorithm with difference evolution was selected as optimization method. ► Model and method proposed were verified by case study with feasible operation solutions. - Abstract: Information hidden in the characteristics and relationship data of a cascade hydropower stations can be extracted by data-mining approaches to be operation rules and optimization support information. In this paper, with Three-gorge and Gezhouba cascade hydropower stations as an example, two operation rules are proposed due to different operation efficiency of water turbines and tight water volume and hydraulic relationship between two hydropower stations. The rules are applied to improve optimization model with more exact decision and state variables and constraints. They are also used in the population initiation step to develop better individuals with culture algorithm with differential evolution as an optimization method. In the case study, total feasible population and the best solution based on an initial population with an operation rule can be obtained with a shorter computation time than that of a pure random initiated population. Amount of electricity generation in a dispatch period with an operation rule also increases with an average increase rate of 0.025%. For a fixed water discharge process of Three-gorge hydropower station, there is a better rule to decide an operation plan of Gezhouba hydropower station in which total hydraulic head for electricity generation is optimized and distributed with inner-plant economic operation considered.

Value of ecosystem hydropower service and its impact on the payment for ecosystem services.

Science.gov (United States)

Fu, B; Wang, Y K; Xu, P; Yan, K; Li, M

2014-02-15

Hydropower is an important service provided by ecosystems. We surveyed all the hydropower plants in the Zagunao River Basin, Southwest China. Then, we assessed the hydropower service by using the InVEST (The Integrated Value and Tradeoff of Ecosystem Service Tools) model. Finally, we discussed the impact on ecological compensation. The results showed that: 1) hydropower service value of ecosystems in the Zagunao River Basin is 216.29 Euro/hm(2) on the average, of which the high-value area with more than 475.65 Euro/hm(2) is about 750.37 km(2), accounting for 16.12% of the whole watershed, but it provides 53.47% of the whole watershed service value; 2) ecosystem is an ecological reservoir with a great regulation capacity. Dams cannot completely replace the reservoir water conservation function of ecosystems, and has high economic and environmental costs that must be paid as well. Compensation for water conservation services should become an important basis for ecological compensation of hydropower development. 3) In the current PES cases, the standard of compensation is generally low. Cascade development makes the value of upstream ecosystem services become more prominent, reflecting the differential rent value, and the value of ecosystem services should be based on the distribution of differentiated ecological compensation. Copyright © 2013 Elsevier B.V. All rights reserved.

EPRI-DOE Conference on Environmentally-Enhanced Hydropower Turbines: Technical Papers

Energy Technology Data Exchange (ETDEWEB)

Hogan, T. [Alden Research Laboratory, Inc., Holden, MA (United States)

2011-12-01

The EPRI-DOE Conference on Environmentally-Enhanced Hydropower Turbines was a component of a larger project. The goal of the overall project was to conduct the final developmental engineering required to advance the commercialization of the Alden turbine. As part of this effort, the conference provided a venue to disseminate information on the status of the Alden turbine technology as well as the status of other advanced turbines and research on environmentally-friendly hydropower turbines. The conference was also a product of a federal Memorandum of Understanding among DOE, USBR, and USACE to share technical information on hydropower. The conference was held in Washington, DC on May 19 and 20, 2011 and welcomed over 100 attendees. The Conference Organizing Committee included the federal agencies with a vested interest in hydropower in the U.S. The Committee collaboratively assembled this conference, including topics from each facet of the environmentally-friendly conventional hydropower research community. The conference was successful in illustrating the readiness of environmentally-enhanced hydropower technologies. Furthermore, the topics presented illustrated the need for additional deployment and field testing of these technologies in an effort to promote the growth of environmentally sustainable hydropower in the U.S. and around the world.

Developing a module for estimating climate warming effects on hydropower pricing in California

International Nuclear Information System (INIS)

Guégan, Marion; Uvo, Cintia B.; Madani, Kaveh

2012-01-01

Climate warming is expected to alter hydropower generation in California through affecting the annual stream-flow regimes and reducing snowpack. On the other hand, increased temperatures are expected to increase hydropower demand for cooling in warm periods while decreasing demand for heating in winter, subsequently altering the annual hydropower pricing patterns. The resulting variations in hydropower supply and pricing regimes necessitate changes in reservoir operations to minimize the revenue losses from climate warming. Previous studies in California have only explored the effects of hydrological changes on hydropower generation and revenues. This study builds a long-term hydropower pricing estimation tool, based on artificial neural network (ANN), to develop pricing scenarios under different climate warming scenarios. Results suggest higher average hydropower prices under climate warming scenarios than under historical climate. The developed tool is integrated with California's Energy-Based Hydropower Optimization Model (EBHOM) to facilitate simultaneous consideration of climate warming on hydropower supply, demand and pricing. EBHOM estimates an additional 5% drop in annual revenues under a dry warming scenario when climate change impacts on pricing are considered, with respect to when such effects are ignored, underlining the importance of considering changes in hydropower demand and pricing in future studies and policy making. - Highlights: ► Addressing the major gap in previous climate change and hydropower studies in California. ► Developing an ANN-based long-term hydropower price estimation tool. ► Estimating climate change effects on hydropower demand and pricing in California. ► Investigating the sensitivity of hydropower operations to future price changes. ► Underlining the importance of consideration of climate change impacts on electricity pricing.

Hydropower Regulatory and Permitting Information Desktop (RAPID) Toolkit

Energy Technology Data Exchange (ETDEWEB)

Levine, Aaron L [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

2017-12-19

Hydropower Regulatory and Permitting Information Desktop (RAPID) Toolkit presentation from the WPTO FY14-FY16 Peer Review. The toolkit is aimed at regulatory agencies, consultants, project developers, the public, and any other party interested in learning more about the hydropower regulatory process.

Aerosol nucleation in an ultra-low ion density environment

DEFF Research Database (Denmark)

Pedersen, Jens Olaf Pepke; Enghoff, Martin Andreas Bødker; Paling, Sean M.

2012-01-01

Ion-induced nucleation has been studied in a deep underground ultra-low background radiation environment where the role of ions can be distinguished from alternative neutral aerosol nucleation mechanisms. Our results demonstrate that ions have a significant effect on the production of small...... sulfuric acid–water clusters over a range of sulfuric acid concentrations although neutral nucleation mechanisms remain evident at low ionization levels. The effect of ions is found both to enhance the nucleation rate of stable clusters and the initial growth rate. The effects of possible contaminations...

GRABGAM Analysis of Ultra-Low-Level HPGe Gamma Spectra

International Nuclear Information System (INIS)

Winn, W.G.

1999-01-01

The GRABGAM code has been used successfully for ultra-low level HPGe gamma spectrometry analysis since its development in 1985 at Savannah River Technology Center (SRTC). Although numerous gamma analysis codes existed at that time, reviews of institutional and commercial codes indicated that none addressed all features that were desired by SRTC. Furthermore, it was recognized that development of an in-house code would better facilitate future evolution of the code to address SRTC needs based on experience with low-level spectra. GRABGAM derives its name from Gamma Ray Analysis BASIC Generated At MCA/PC

GRABGAM Analysis of Ultra-Low-Level HPGe Gamma Spectra

Energy Technology Data Exchange (ETDEWEB)

Winn, W.G.

1999-07-28

The GRABGAM code has been used successfully for ultra-low level HPGe gamma spectrometry analysis since its development in 1985 at Savannah River Technology Center (SRTC). Although numerous gamma analysis codes existed at that time, reviews of institutional and commercial codes indicated that none addressed all features that were desired by SRTC. Furthermore, it was recognized that development of an in-house code would better facilitate future evolution of the code to address SRTC needs based on experience with low-level spectra. GRABGAM derives its name from Gamma Ray Analysis BASIC Generated At MCA/PC.

"Head up and eyes out" advances in head mounted displays capabilities

Science.gov (United States)

Cameron, Alex

2013-06-01

There are a host of helmet and head mounted displays, flooding the market place with displays which provide what is essentially a mobile computer display. What sets aviators HMDs apart is that they provide the user with accurate conformal information embedded in the pilots real world view (see through display) where the information presented is intuitive and easy to use because it overlays the real world (mix of sensor imagery, symbolic information and synthetic imagery) and enables them to stay head up, eyes out, - improving their effectiveness, reducing workload and improving safety. Such systems are an enabling technology in the provision of enhanced Situation Awareness (SA) and reducing user workload in high intensity situations. Safety Is Key; so the addition of these HMD functions cannot detract from the aircrew protection functions of conventional aircrew helmets which also include life support and audio communications. These capabilities are finding much wider application in new types of compact man mounted audio/visual products enabled by the emergence of new families of micro displays, novel optical concepts and ultra-compact low power processing solutions. This papers attempts to capture the key drivers and needs for future head mounted systems for aviation applications.

Frequency Stability of Hierarchically Controlled Hybrid Photovoltaic-Battery-Hydropower Microgrids

DEFF Research Database (Denmark)

Guan, Yajuan; Quintero, Juan Carlos Vasquez; Guerrero, Josep M.

2015-01-01

-based local grid is supplied. In this case, the PV-battery system will operate as a PQ bus to inject the desired active and reactive powers to local grid, while the hydropower station will act as a slack bus which maintains its voltage amplitude and frequency. An integrated small-signal state-space model......, a hierarchical controller for hybrid PV-battery-hydropower microgrid is proposed in order to achieve the parallel operation of hydropower and PV-battery system with different rates, and to guarantee power sharing performance among PV voltage controlled inverters, while the required power to hydropower...

MAXIMIZING HYDROPOWER PRODUCTION FROM RESERVOIRS:THE CASE STUDY OF MARKABA

International Nuclear Information System (INIS)

Jaafar, H.

2014-01-01

Hydropower is a form of renewable energy that is clean and cheap. Under uncertain climatic conditions, maximization of hydropower production becomes a challenging task.Stochastic Dynamic programming (SDP) is a promising optimization algorithm that is usedfor complex non-linear reservoir operational policies and strategies.In this research, a combined simulation-SDPoptimization model isdeveloped andverified for maximizing large-scale hydropower production in a monthly time step. The model isdeveloped to generate optimal operational policies for the Qarawn reservoir in Lebanon and test these policies in real time conditions. The model isused to derive operational regimes for the Qarawn reservoirunder varying flows using transitional probability matrices. Simulating the derived rules and the generated operational policies proved effective in maximizingthe hydropower production from the Markaba power plant. The model could be successfully applied to other hydropower dams in the region. (author)

Prediction of small hydropower plant power production in Himreen Lake dam (HLD using artificial neural network

Directory of Open Access Journals (Sweden)

Ali Thaeer Hammid

2018-03-01

Full Text Available In developing countries, the power production is properly less than the request of power or load, and sustaining a system stability of power production is a trouble quietly. Sometimes, there is a necessary development to the correct quantity of load demand to retain a system of power production steadily. Thus, Small Hydropower Plant (SHP includes a Kaplan turbine was verified to explore its applicability. This paper concentrates on applying on Artificial Neural Networks (ANNs by approaching of Feed-Forward, Back-Propagation to make performance predictions of the hydropower plant at the Himreen lake dam-Diyala in terms of net turbine head, flow rate of water and power production that data gathered during a research over a 10 year period. The model studies the uncertainties of inputs and output operation and there's a designing to network structure and then trained by means of the entire of 3570 experimental and observed data. Furthermore, ANN offers an analyzing and diagnosing instrument effectively to model performance of the nonlinear plant. The study suggests that the ANN may predict the performance of the plant with a correlation coefficient (R between the variables of predicted and observed output that would be higher than 0.96. Keywords: Himreen Lake Dam, Small Hydropower plants, Artificial Neural Networks, Feed forward-back propagation model, Generation system's prediction

Assessment of small hydropower potential by software. Case study

Directory of Open Access Journals (Sweden)

Moldoveanu Alexandru

2017-01-01

Full Text Available The rivers hydropower potential is considered one of the oldest renewable energy source used in the electricity production process. A method to investigate the possibility to construct a micro hydropower system on a small river is presented. The analysis and the hydropower assessment were done by using Vapidro-Aste software. Results point out that micro-hydro units can be implemented in remote locations or hybrid renewable energy systems, while the environmental flow is guaranteed.

Modelling the feasibility of retrofitting hydropower to existing South ...

African Journals Online (AJOL)

sources (including nuclear energy) will be nearly 30% (Eskom,. 2011). South Africa ... Hydropower has the following advantages over other forms of .... well as negative environmental impacts. ... Potential environmental impacts of hydropower.

Ultra-low noise supercontinuum source for ultra-high resolution optical coherence tomography at 1300 nm

Science.gov (United States)

Gonzalo, I. B.; Maria, M.; Engelsholm, R. D.; Feuchter, T.; Leick, L.; Moselund, P. M.; Podoleanu, A.; Bang, O.

2018-02-01

Supercontinuum (SC) sources are of great interest for many applications due to their ultra-broad optical bandwidth, good beam quality and high power spectral density [1]. In particular, the high average power over large bandwidths makes SC light sources excellent candidates for ultra-high resolution optical coherence tomography (UHR-OCT) [2-5]. However, conventional SC sources suffer from high pulse-to-pulse intensity fluctuations as a result of the noise-sensitive nonlinear effects involved in the SC generation process [6-9]. This intensity noise from the SC source can limit the performance of OCT, resulting in a reduced signal-to-noise ratio (SNR) [10-12]. Much work has been done to reduce the noise of the SC sources for instance with fiber tapers [7,8] or increasing the repetition rate of the pump laser for averaging in the spectrometer [10,12]. An alternative approach is to use all-normal dispersion (ANDi) fibers [13,14] to generate SC light from well-known coherent nonlinear processes [15-17]. In fact, reduction of SC noise using ANDi fibers compared to anomalous dispersion SC pumped by sub-picosecond pulses has been recently demonstrated [18], but a cladding mode was used to stabilize the ANDi SC. In this work, we characterize the noise performance of a femtosecond pumped ANDi based SC and a commercial SC source in an UHR-OCT system at 1300 nm. We show that the ANDi based SC presents exceptional noise properties compared to a commercial source. An improvement of 5 dB in SNR is measured in the UHR-OCT system, and the noise behavior resembles that of a superluminiscent diode. This preliminary study is a step forward towards development of an ultra-low noise SC source at 1300 nm for ultra-high resolution OCT.

Hydrological assessment for mini hydropower potential at Sungai Pahang - Temerloh

International Nuclear Information System (INIS)

Sidek, L M; Zaki, A Z A; Muda, Z C; Basri, H; Mustaffa, Z; Ibrahim, M I H; Thiruchelvam, S

2013-01-01

Sg Pahang at Temerloh was considered for assessment of hydropower potential using hydrological analysis method and hydrological model. The available data related to topography, soil, land use, weather and discharge pertaining to the study catchment were used to characterize the catchment. The characterization was required for water resources hence hydropower assessment. The hydrology of the study catchment was simulated through the model. This hydrological study is required due to the proposed mini hydroelectric power plant at Pulau Temerloh. It is essential to evaluate the existing river flow characteristic and to model the environmental flow assessment of the river. Two rainfalll stations, JPS Temerloh and Pintu Kawalan Paya Kertam Station are selected to develop the Rainfall Intensity Duration frequency (RIDF) Curve to determine the rainfall intensity of the area. Daily river flow were recorded at Sg Pahang at Temerloh and Sg Pahang at Lubok Paku were used to develop the Flow Duration Curve (FDC) to study the characteristic of Sungai Pahang flow. The 7 days low flow with 10 years return period (7Q10 low flow) was obtained using both Gumbel Method and Log Pearson Type III Method. The results from FDC shows that 50% percentage of time the Sg Pahang - Temerloh is exceeded over a historical period is 400 m 3 /s and 50% percentage of time the Sg Pahang - Lubok Paku is exceeded over a historical period is 650 m 3 /s. The required environmental flow are set to be 7Q10 low flow which is 64.215 m 3 /s for Sg Pahang at Temerloh and 79.24 m 3 /s for Sg Pahang at Lubok Paku. The results show the water resources are abundant and hence boost the mini hydropower potentiality at Sg Pahang.

Flow Regime Changes: From Impounding a Temperate Lowland River to Small Hydropower Operations

Directory of Open Access Journals (Sweden)

Petras Punys

2015-07-01

Full Text Available This article discusses the environmental issues facing small hydropower plants (SHPs operating in temperate lowland rivers of Lithuania. The research subjects are two medium head reservoir type hydro schemes considered within a context of the global fleet of SHPs in the country. This research considers general abiotic indicators (flow, level, water retention time in the reservoirs of the stream that may affect the aquatic systems. The main idea was to test whether the hydrologic regime has been altered by small hydropower dams. The analysis of changes in abiotic indicators is a complex process, including both pre- and post-reservoir construction and post commissioning of the SHPs under operation. Downstream hydrograph (flow and stage ramping is also an issue for operating SHPs that can result in temporary rapid changes in flow and consequently negatively impact aquatic resources. This ramping has been quantitatively evaluated. To avoid the risk of excessive flow ramping, the types of turbines available were evaluated and the most suitable types for the natural river flow regime were identified. The results of this study are to allow for new hydro schemes or upgrades to use water resources in a more sustainable way.

Security Implications for Ultra-Low Power Configurable SoC FPAA Embedded Systems

Directory of Open Access Journals (Sweden)

Jennifer Hasler

2018-06-01

Full Text Available We discuss the impact of physical computing techniques to classifying network security issues for ultra-low power networked IoT devices. Physical computing approaches enable at least a factor of 1000 improvement in computational energy efficiency empowering a new generation of local computational structures for embedded IoT devices. These techniques offer computational capability to address network security concerns. This paper begins the discussion of security opportunities for, and issues using, FPAA devices for small embedded IoT platforms. These FPAAs enable devices often utilized for low-power context aware computation. Embedded FPAA devices have both positive Security attributes, as well as potential vulnerabilities. FPAA devices can be part of the resulting secure computation, such as implementing unique functions. FPAA devices can be used investigate security of analog/mixed signal capabilities. The paper concludes with summarizing key improvements for secure ultra-low power embedded FPAA devices.

Development potential for hydropower; Ausbaupotential der Wasserkraft

Energy Technology Data Exchange (ETDEWEB)

Laufer, F.; Groetzinger, S.; Peter, M.; Schmutz, A.

2004-11-15

This comprehensive report for the Swiss Federal Office of Energy (SFOE) takes a look at the potential for the development of hydropower in Switzerland. The report updates the energy perspectives made ten years earlier. An overview of Swiss electricity production and consumption is presented and the proportion provided by hydropower is noted. Figures on installed capacity and import/export quantities are presented and discussed. Technological developments and the economical frameworks involved are discussed, as are regulatory measures that can be taken. Theoretical and technically realisable potentials for increased use of hydropower are discussed. The methods used to do this are examined. Strategies and measures to be taken are listed and discussed. An appendix includes data sheets on power plant modelling, including examples

Bake hardening of ultra-fine grained low carbon steel produced by constrained groove pressing

International Nuclear Information System (INIS)

Alihosseini, H.; Dehghani, K.

2012-01-01

Highlights: ► BH of UFG low carbon steel sheets was studied. ► Three passes of CGP are used for producing of UFG sheets. ► Maximum BH was achieved to the UFG specimen pre-strained 8% by baking at 250 °C. - Abstract: In the present work, the bake hardening of ultra-fine grained low carbon steel was compared with that of its coarse-grain counterpart. The ultra-fine grained sheets were produced by applying three passes of constrained groove pressing resulting the grains of 260–270 nm. The microstructure of ultra-fine grain specimens were characterized using electron back-scatter diffraction technique. Then, the bake hardenability of ultra-fine grain and coarse-grain samples were compared by pre-straining to 4, 6 and 8% followed by baking at 150 °C and 250 °C for 20 min. The results show that in case of baking at 250 °C, there was an increase about 108%, 93%, and 72% in the bake hardening for 4%, 6% and 8% pre-strain, respectively. As for baking at 150 °C, these values were 170%, 168%, and 100%, respectively for 4%, 6% and 8% pre-strain. The maximum in bake hardenability (103 MPa) and final yield stress (563 MPa) were pertaining to the ultra-fine grain specimen pre-strained 8% followed by baking at 250 °C.

Silicon for ultra-low-level detectors and sup 32 Si

Energy Technology Data Exchange (ETDEWEB)

Plaga, R. (Max Planck Inst. fuer Kernphysik, Heidelberg (Germany))

1991-11-15

A recent dark matter experiment using a silicon diode detector confirms that the decay of {sup 32}Si is a dangerous background in ultra-low-level experiments using silicon as detector material or shielding. In this Letter we study the mechanism of how {sup 32}Si enters commercially available silicon. Ways to avoid this contamination are pointed out. Limits on the {sup 32}Si content of silicon from measurements with miniaturized low-level proportional counters are also given. (orig.).

Game theory competition analysis of reservoir water supply and hydropower generation

Science.gov (United States)

Lee, T.

2013-12-01

The total installed capacity of the power generation systems in Taiwan is about 41,000 MW. Hydropower is one of the most important renewable energy sources, with hydropower generation capacity of about 4,540 MW. The aim of this research is to analyze competition between water supply and hydropower generation in water-energy systems. The major relationships between water and energy systems include hydropower generation by water, energy consumption for water system operation, and water consumption for energy system. In this research, a game-theoretic Cournot model is formulated to simulate oligopolistic competition between water supply, hydropower generation, and co-fired power generation in water-energy systems. A Nash equilibrium of the competitive market is derived and solved by GAMS with PATH solver. In addition, a case study analyzing the competition among water supply and hydropower generation of De-ji and Ku-Kuan reservoirs, Taipower, Star Energy, and Star-Yuan power companies in central Taiwan is conducted.

Effect of Diluent on Ultra-low Temperature Curable Conductive Silver Adhesive

Science.gov (United States)

Zhou, Xingli; Wang, Likun; Liao, Qingwei; Yan, Chao; Du, Haibo; Qin, Lei

2018-03-01

The ultra-low temperature curable conductive silver adhesive needed urgently for the surface conductive treatment of piezoelectric composite material. The effect of diluent acetone on ultra-low temperature curable conductive silver adhesive were investigated for surface conductive treatment of piezoelectric composite material. In order to improve the operability and extend the life of the conductive adhesive, the diluent was added to dissolve and disperse conductive adhesive. With the increase of the content of diluent, the volume resistivity of conductive adhesive decreased at first and then increased, and the shear strength increased at first and then decreased. When the acetone content is 10%, the silver flaky bonded together, arranged the neatest, the smallest gap, the most closely connected, the surface can form a complete conductive network, and the volume resistivity is 2.37 × 10-4Ω · cm, the shear strength is 5.13MPa.

SLH Timing Belt Powertrain

Energy Technology Data Exchange (ETDEWEB)

Schneider, Abe

2014-04-09

The main goal of this proposal was to develop and test a novel powertrain solution for the SLH hydroEngine, a low-cost, efficient low-head hydropower technology. Nearly two-thirds of U.S. renewable electricity is produced by hydropower (EIA 2010). According to the U.S. Department of Energy; this amount could be increased by 50% with small hydropower plants, often using already-existing dams (Hall 2004). There are more than 80,000 existing dams, and of these, less than 4% generate power (Blankinship 2009). In addition, there are over 800 irrigation districts in the U.S., many with multiple, non-power, low-head drops. These existing, non-power dams and irrigation drops could be retrofitted to produce distributed, baseload, renewable energy with appropriate technology. The problem is that most existing dams are low-head, or less than 30 feet in height (Ragon 2009). Only about 2% of the available low-head hydropower resource in the U.S. has been developed, leaving more than 70 GW of annual mean potential low-head capacity untapped (Hall 2004). Natel Energy, Inc. is developing a low-head hydropower turbine that operates efficiently at heads less than 6 meters and is cost-effective for deployment across multiple low-head structures. Because of the unique racetrack-like path taken by the prime-movers in the SLH, a flexible powertrain is required. Historically, the only viable technological solution was roller chain. Despite the having the ability to easily attach blades, roller chain is characterized by significant drawbacks, including high cost, wear, and vibration from chordal action. Advanced carbon- fiber-reinforced timing belts have been recently developed which, coupled with a novel belt attachment system developed by Natel Energy, result in a large reduction in moving parts, reduced mass and cost, and elimination of chordal action for increased fatigue life. The work done in this project affirmatively addressed each of the following 3 major uncertainties concerning

ESTIMATING HYDROPOWER POTENTIAL OF SMALL RIVERS OF REPUBLIC OF MOLDOVA USING GIS

Directory of Open Access Journals (Sweden)

T. CASTRAVEŢ

2018-06-01

Full Text Available Estimating hydropower potential of small rivers of Republic of Moldova using GIS, The increasing demand for energy, especially from renewable and sustainable sources, spurs the development of small hydropower plants and encourages investment in new survey studies (Larentis et al., 2010. Preliminary hydropower survey studies usually carry huge uncertainties about the technical, economic and environmental feasibility of the undeveloped potential. This paper presents a methodology for hydropower potential sites assessment. The sequence of procedures to identify hydropower sites is based on remote sensing data and streamflow and rainfall data and was automated within GIS environment.

Hydropower's Contribution to Energy Security

Energy Technology Data Exchange (ETDEWEB)

Altinbilek, D.; Abdel-Malek, R.; Devernay, J.M.; Gill, R.; Leney, S.; Moss, Terry; Schiffer, H.P.; Taylor, R.M.

2007-07-01

The role of hydropower within mixed power systems is analysed from the point of view of both quantitative and qualitative performance. Interrelationships with all other generation technologies are discussed and synergies identified. Resources, sustainability criteria and investment challenges are reviewed in the context of development. The objective of the paper is to define hydropower's contribution within the clean, clever and competitive markets of the future.

Ultra-low-frequency dust-electromagnetic modes in self-gravitating magnetized dusty plasmas

International Nuclear Information System (INIS)

Banerjee, A.K.; Alam, M.N.; Mamun, A.A.

2001-01-01

Obliquely propagating ultra-low-frequency dust-electromagnetic waves in a self-gravitating, warm, magnetized, two fluid dusty plasma system have been investigated. Two special cases, namely, dust-Alfven mode propagating parallel to the external magnetic field and dust- magnetosonic mode propagating perpendicular to the external magnetic field have also been considered. It has been shown that effects of self-gravitational field, dust fluid temperature, and obliqueness significantly modify the dispersion properties of these ultra-low-frequency dust-electromagnetic modes. It is also found that in parallel propagating dust-Alfven mode these effects play no role, but in obliquely propagating dust-Alfven mode or perpendicular propagating dust-magnetosonic mode the effect of self-gravitational field plays destabilizing role whereas the effect of dust/ion fluid temperature plays stabilizing role. (author)

Refurbishment of hydropower generation plants

International Nuclear Information System (INIS)

Kofler, W.

2001-01-01

This article presents the factors taken into consideration and the methods used for the management of refurbishment work in the hydropower installations of the TUWAG - a Tyrolean hydropower company in Austria. The technical and financial advantages to be gained from refurbishment are discussed and the requirements placed on the structuring of refurbishment projects are described. Various factors such as plant operation and maintenance, increased returns through better efficiency and cost reduction through lower wear and tear and reduced risk of failure are discussed. Annexes to the article cover monitoring and measurement techniques, the simulation of mechanical and hydraulic conditions, profitability calculations and turbine management

Balancing hydropower production and river bed incision in operating a run-of-river hydropower scheme along the River Po

Science.gov (United States)

Denaro, Simona; Dinh, Quang; Bizzi, Simone; Bernardi, Dario; Pavan, Sara; Castelletti, Andrea; Schippa, Leonardo; Soncini-Sessa, Rodolfo

2013-04-01

Water management through dams and reservoirs is worldwide necessary to support key human-related activities ranging from hydropower production to water allocation, and flood risk mitigation. Reservoir operations are commonly planned in order to maximize these objectives. However reservoirs strongly influence river geomorphic processes causing sediment deficit downstream, altering the flow regime, leading, often, to process of river bed incision: for instance the variations of river cross sections over few years can notably affect hydropower production, flood mitigation, water supply strategies and eco-hydrological processes of the freshwater ecosystem. The river Po (a major Italian river) has experienced severe bed incision in the last decades. For this reason infrastructure stability has been negatively affected, and capacity to derive water decreased, navigation, fishing and tourism are suffering economic damages, not to mention the impact on the environment. Our case study analyzes the management of Isola Serafini hydropower plant located on the main Po river course. The plant has a major impact to the geomorphic river processes downstream, affecting sediment supply, connectivity (stopping sediment upstream the dam) and transport capacity (altering the flow regime). Current operation policy aims at maximizing hydropower production neglecting the effects in term of geomorphic processes. A new improved policy should also consider controlling downstream river bed incision. The aim of this research is to find suitable modeling framework to identify an operating policy for Isola Serafini reservoir able to provide an optimal trade-off between these two conflicting objectives: hydropower production and river bed incision downstream. A multi-objective simulation-based optimization framework is adopted. The operating policy is parameterized as a piecewise linear function and the parameters optimized using an interactive response surface approach. Global and local

Ultra-low current biosensor output detection using portable electronic reader

Science.gov (United States)

Yahaya, N. A. N.; Rajapaksha, R. D. A. A.; Uda, M. N. Afnan; Hashim, U.

2017-09-01

Generally, the electrical biosensor usually shows extremely low current signal output around pico ampere to microampere range. In this research, electronic reader with amplifier has been demonstrated to detect ultra low current via the biosensor. The operational amplifier Burr-Brown OPA 128 and Arduino Uno board were used to construct the portable electronic reader. There are two cascaded inverting amplifier were used to detect ultra low current through the biosensor from pico amperes (pA) to nano amperes ranges (nA). A small known input current was form by applying variable voltage between 0.1V to 5.0V across a 5GΩ high resistor to check the amplifier circuit. The amplifier operation was measured with the high impedance current source and has been compared with the theoretical measurement. The Arduino Uno was used to convert the analog signal to digital signal and process the data to display on reader screen. In this project, Proteus software was used to design and test the circuit. Then it was implemented together with Arduino Uno board. Arduino board was programmed using C programming language to make whole circuit communicate each order. The current was measured then it shows a small difference values compared to theoretical values, which is approximately 14pA.

Addressing biogenic greenhouse gas emissions from hydropower in LCA.

Science.gov (United States)

Hertwich, Edgar G

2013-09-03

The ability of hydropower to contribute to climate change mitigation is sometimes questioned, citing emissions of methane and carbon dioxide resulting from the degradation of biogenic carbon in hydropower reservoirs. These emissions are, however, not always addressed in life cycle assessment, leading to a bias in technology comparisons, and often misunderstood. The objective of this paper is to review and analyze the generation of greenhouse gas emissions from reservoirs for the purpose of technology assessment, relating established emission measurements to power generation. A literature review, data collection, and statistical analysis of methane and CO2 emissions are conducted. In a sample of 82 measurements, methane emissions per kWh hydropower generated are log-normally distributed, ranging from micrograms to 10s of kg. A multivariate regression analysis shows that the reservoir area per kWh electricity is the most important explanatory variable. Methane emissions flux per reservoir area are correlated with the natural net primary production of the area, the age of the power plant, and the inclusion of bubbling emissions in the measurement. Even together, these factors fail to explain most of the variation in the methane flux. The global average emissions from hydropower are estimated to be 85 gCO2/kWh and 3 gCH4/kWh, with a multiplicative uncertainty factor of 2. GHG emissions from hydropower can be largely avoided by ceasing to build hydropower plants with high land use per unit of electricity generated.

Short-term forecasting model for aggregated regional hydropower generation

International Nuclear Information System (INIS)

Monteiro, Claudio; Ramirez-Rosado, Ignacio J.; Fernandez-Jimenez, L. Alfredo

2014-01-01

Highlights: • Original short-term forecasting model for the hourly hydropower generation. • The use of NWP forecasts allows horizons of several days. • New variable to represent the capacity level for generating hydroelectric energy. • The proposed model significantly outperforms the persistence model. - Abstract: This paper presents an original short-term forecasting model of the hourly electric power production for aggregated regional hydropower generation. The inputs of the model are previously recorded values of the aggregated hourly production of hydropower plants and hourly water precipitation forecasts using Numerical Weather Prediction tools, as well as other hourly data (load demand and wind generation). This model is composed of three modules: the first one gives the prediction of the “monthly” hourly power production of the hydropower plants; the second module gives the prediction of hourly power deviation values, which are added to that obtained by the first module to achieve the final forecast of the hourly hydropower generation; the third module allows a periodic adjustment of the prediction of the first module to improve its BIAS error. The model has been applied successfully to the real-life case study of the short-term forecasting of the aggregated hydropower generation in Spain and Portugal (Iberian Peninsula Power System), achieving satisfactory results for the next-day forecasts. The model can be valuable for agents involved in electricity markets and useful for power system operations

Hydropower and biomass as renewable energy sources in Turkey

International Nuclear Information System (INIS)

Kaygusuz, K.

2001-01-01

When talking about renewable energy sources today, the most important and economical energy sources for Turkey are hydropower and biomass.The present study gives a review of production, consumption, and economics of hydropower and biomass as renewable energy sources in Turkey. Turkey has a total gross hydropower potential of 433 GW, but only 125 GW of the total hydroelectric potential of Turkey can be economically used. By the commissioning of new hydropower plants, which are under construction, 36% of the economically usable potential of the country could be tapped. On the other hand, biomass (wood and wastes) energy is the second most important renewable energy source for Turkey. However, the biomass energy sources of Turkey are limited. In 1998, the biomass share of the total energy consumption of the country is 10%. In this study, the potential of important biomass energy sources and animal solid wastes of the country were determined. The effects of hydropower and biomass usage on the environment were also discussed. Considering total cereal products and fatty seed plants, approximately 50-60 million tons per year of biomass and 8-10 million tons of solid matter animal waste are produced, and 70% of total biomass is seen as being usable for energy. Some useful suggestions and recommendations are also presented. The present study shows that there is an important potential for hydropower and biomass energy sources in Turkey. (author)

Hydropower's role in delivering sustainability

International Nuclear Information System (INIS)

Altinbilek, D.; Seelos, K.; Taylor, R.

2005-01-01

Johannesburg's World Summit on Sustainable Development stipulated in its Implementation Plan that hydropower of all scales should be included in the drive to increase the contribution of renewable energy. This can be achieved through the plant-life extension and upgrading of existing schemes as well as by the sustainable development of new projects according to the needs, opportunities and resources available. Hydropower is the world's largest source of renewable energy used for power generation; it accounts for 19 percent of the world's supply (by 2010 wind power is expected to contribute 0.6 percent and solar power 0.12 percent. Hydropower is also a truly global resource, as more than 150 countries generate hydroelectric power. There is about 730 GW of hydro capacity in operation worldwide, generating 2650 TWh/year. A further 101 GW is under construction and 338 GW is at the planning stage. Hydropower plays an important role in reducing global GhG emissions by an estimated 10 percent per annum; in its current role, hydropower offsets 4.4 million barrels of oil-equivalent (thermal electric generation) each day. There is vast unexploited potential worldwide for new hydro plants, with only 33 percent of the economic potential having been developed so far. The majority of the remaining potential exists in lesser developed countries in Asia, South America and Africa. For example, Europe has developed 75 percent of its economic potential, whereas Africa has only developed seven percent. Hydropower technologies are reliable, advanced and efficient. The energy conversion efficiency of 80 to 93 percent is far higher than that for other major types of power plant. The level of service from the various types of hydro scheme varies from base-load supply, typically from run-of-river schemes, to peak-load and system-back-up services from hydro storage schemes. In regions where there is long-developed hydro capacity, plant-life extension can be achieved by the replacement of

Estimation of economic parameters of U.S. hydropower resources

Energy Technology Data Exchange (ETDEWEB)

Hall, Douglas G. [Idaho National Lab. (INL), Idaho Falls, ID (United States). Idaho National Engineering and Environmental Lab. (INEEL); Hunt, Richard T. [Idaho National Lab. (INL), Idaho Falls, ID (United States). Idaho National Engineering and Environmental Lab. (INEEL); Reeves, Kelly S. [Idaho National Lab. (INL), Idaho Falls, ID (United States). Idaho National Engineering and Environmental Lab. (INEEL); Carroll, Greg R. [Idaho National Lab. (INL), Idaho Falls, ID (United States). Idaho National Engineering and Environmental Lab. (INEEL)

2003-06-01

Tools for estimating the cost of developing and operating and maintaining hydropower resources in the form of regression curves were developed based on historical plant data. Development costs that were addressed included: licensing, construction, and five types of environmental mitigation. It was found that the data for each type of cost correlated well with plant capacity. A tool for estimating the annual and monthly electric generation of hydropower resources was also developed. Additional tools were developed to estimate the cost of upgrading a turbine or a generator. The development and operation and maintenance cost estimating tools, and the generation estimating tool were applied to 2,155 U.S. hydropower sites representing a total potential capacity of 43,036 MW. The sites included totally undeveloped sites, dams without a hydroelectric plant, and hydroelectric plants that could be expanded to achieve greater capacity. Site characteristics and estimated costs and generation for each site were assembled in a database in Excel format that is also included within the EERE Library under the title, “Estimation of Economic Parameters of U.S. Hydropower Resources - INL Hydropower Resource Economics Database.”

Reevaluation of Turkey's hydropower potential and electric energy demand

International Nuclear Information System (INIS)

Yueksek, Omer

2008-01-01

This paper deals with Turkey's hydropower potential and its long-term electric energy demand predictions. In the paper, at first, Turkey's energy sources are briefly reviewed. Then, hydropower potential is analyzed and it has been concluded that Turkey's annual economically feasible hydropower potential is about 188 TWh, nearly 47% greater than the previous estimation figures of 128 TWh. A review on previous prediction models for Turkey's long-term electric energy demand is presented. In order to predict the future demand, new increment ratio scenarios, which depend on both observed data and future predictions of population, energy consumption per capita and total energy consumption, are developed. The results of 11 prediction models are compared and analyzed. It is concluded that Turkey's annual electric energy demand predictions in 2010, 2015 and 2020 vary between 222 and 242 (average 233) TWh; 302 and 356 (average 334) TWh; and 440 and 514 (average 476) TWh, respectively. A discussion on the role of hydropower in meeting long-term demand is also included in the paper and it has been predicted that hydropower can meet 25-35% of Turkey's electric energy demand in 2020

[Reparative Osteogenesis and Angiogenesis in Low Intensity Electromagnetic Radiation of Ultra-High Frequency].

Science.gov (United States)

Iryanov, Y M; Kiryanov, N A

2015-01-01

Non-drug correction of reparative bone tissue regeneration in different pathological states - one of the most actual problems of modern medicine. Our aim was to conduct morphological analysis of the influence of electromagnetic radiation of ultra-high frequency and low intensity on reparative osteogenesis and angiogenesis in fracture treatment under transosseous osteosynthesis. A controlled nonrandomized study was carried out. In the experiment conducted on rats we modeled tibial fracture with reposition and fixation of the bone fragments both in control and experimental groups. In the animals of the experimental group the fracture zone was exposed to low intensity electromagnetic radiation of ultra-high frequency. Exposure simulation was performed in the control group. The operated bones were examined using radiography, light and electronic microscopy, X-ray electronic probe microanalysis. It has been established that electromagnetic radiation of ultra-high frequency sessions in fracture treatment stimulate secretory activity and degranulation of mast cells, produce microcirculatory bed vascular permeability increase, endotheliocyte migration phenotype expression, provide endovascular endothelial outgrowth formation, activate reparative osteogenesis and angiogenesis while fracture reparation becomes the one of the primary type. The full periosteal, intermediary and intraosteal bone union was defined in 28 days. Among the therapeutic benefits of electromagnetic radiation of ultra-high frequency in fracture treatment we can detect mast cell secretorv activity stimulation and endovascular anziozenesis activation.

Robust and Energy-Efficient Ultra-Low-Voltage Circuit Design under Timing Constraints in 65/45 nm CMOS

Directory of Open Access Journals (Sweden)

David Bol

2011-01-01

Full Text Available Ultra-low-voltage operation improves energy efficiency of logic circuits by a factor of 10×, at the expense of speed, which is acceptable for applications with low-to-medium performance requirements such as RFID, biomedical devices and wireless sensors. However, in 65/45 nm CMOS, variability and short-channel effects significantly harm robustness and timing closure of ultra-low-voltage circuits by reducing noise margins and jeopardizing gate delays. The consequent guardband on the supply voltage to meet a reasonable manufacturing yield potentially ruins energy efficiency. Moreover, high leakage currents in these technologies degrade energy efficiency in case of long stand-by periods. In this paper, we review recently published techniques to design robust and energy-efficient ultra-low-voltage circuits in 65/45 nm CMOS under relaxed yet strict timing constraints.

Vulnerability of hydropower generation to climate change in China: Results based on Grey forecasting model

International Nuclear Information System (INIS)

Wang, Bing; Liang, Xiao-Jie; Zhang, Hao; Wang, Lu; Wei, Yi-Ming

2014-01-01

This paper analyzes the long-term relationships between hydropower generation and climate factors (precipitation), hydropower generation capacity (installed capacity of hydropower station) to quantify the vulnerability of renewable energy production in China for the case of hydropower generation. Furthermore, this study applies Grey forecasting model to forecast precipitation in different provinces, and then sets up different scenarios for precipitation based on the IPCC Special Report on Emission Scenarios and results from PRECIS (Providing Regional Climate projections for Impacts Studies) model. The most important result found in this research is the increasing hydropower vulnerability of the poorest regions and the main hydropower generation provinces of China to climate change. Other main empirical results reveal that the impacts of climate change on the supply of hydropower generation in China will be noteworthy for the society. Different scenarios have different effects on hydropower generation, of which A2 scenario (pessimistic, high emission) has the largest. Meanwhile, the impacts of climate change on hydropower generation of every province are distinctly different, of which the Southwest part has the higher vulnerability than the average level while the central part lower. - Highlights: • The hydropower vulnerability will be enlarged with the rapid increase of hydropower capacity. • Modeling the vulnerability of hydropower in different scenarios and different provinces. • The increasing hydropower vulnerability of the poorest regions to climate change. • The increasing hydropower vulnerability of the main hydropower generation provinces. • Rainfall pattern caused by climate change would be the reason for the increasing vulnerability

Dynamic analysis of a pumped-storage hydropower plant with random power load

Science.gov (United States)

Zhang, Hao; Chen, Diyi; Xu, Beibei; Patelli, Edoardo; Tolo, Silvia

2018-02-01

This paper analyzes the dynamic response of a pumped-storage hydropower plant in generating mode. Considering the elastic water column effects in the penstock, a linearized reduced order dynamic model of the pumped-storage hydropower plant is used in this paper. As the power load is always random, a set of random generator electric power output is introduced to research the dynamic behaviors of the pumped-storage hydropower plant. Then, the influences of the PI gains on the dynamic characteristics of the pumped-storage hydropower plant with the random power load are analyzed. In addition, the effects of initial power load and PI parameters on the stability of the pumped-storage hydropower plant are studied in depth. All of the above results will provide theoretical guidance for the study and analysis of the pumped-storage hydropower plant.

Loss of European silver eel passing a hydropower station

DEFF Research Database (Denmark)

Pedersen, Michael Ingemann; Jepsen, Niels; Aarestrup, Kim

2012-01-01

The aim of this study was to assess escapement success of silver eels, Anguilla anguilla (L.), in a lowland river while passing a reservoir and a hydropower station. It was hypothesized that passage success would be lowest at the hydropower station and that survival and migration speed would...... that within the study period, only 23% of the tagged eels reached the tidal limit, mainly due to difficulties in passing the hydropower dam. With such high loss-rates, the escapement goals set in the management plan cannot be achieved...

75 FR 67993 - Hydropower Resource Assessment at Existing Reclamation Facilities-Draft Report

Science.gov (United States)

2010-11-04

... DEPARTMENT OF THE INTERIOR Bureau of Reclamation Hydropower Resource Assessment at Existing... comment the ``Hydropower Resource Assessment at Existing Reclamation Facilities'' (HRA) Draft Report. The HRA is an assessment of the economic and technical potential for hydropower development at existing...

75 FR 81643 - Hydropower Resource Assessment at Existing Reclamation Facilities-Draft Report

Science.gov (United States)

2010-12-28

... DEPARTMENT OF THE INTERIOR Bureau of Reclamation Hydropower Resource Assessment at Existing... period for review of the Hydropower Resource Assessment at Existing Reclamation Facilities Draft Report... sustainable, affordable hydropower for our national electricity supplies. Reclamation has 476 dams and 8,116...

Ultra-low-energy (<10 eV/u) ion beam bombardment effect on naked DNA

Energy Technology Data Exchange (ETDEWEB)

Thopan, P. [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Thongkumkoon, P. [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Department of Biology, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Prakrajang, K. [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Faculty of Science, Maejo University, Chiang Mai 50290 (Thailand); Suwannakachorn, D. [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Yu, L.D., E-mail: yuld@thep-center.org [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Thailand Center of Excellence in Physics, Commission on Higher Education, 328 Si Ayutthaya Road, Bangkok 10400 (Thailand)

2014-05-01

Highlights: • Decelerated ultra-low energy ion beam bombarded naked DNA. • DNA form change induced by ion bombardment was investigated. • N-ion bombardment at 32 eV induced DNA single and double strand breaks. • Ar-ion bombardment at a-few-hundreds eV induced DNA single strand break. - Abstract: Since ion energy deposition in the ion-bombarded materials dominantly occurs in the low-energy range, it is very interesting to know effects from ultra-low-energy ion interaction with DNA for understanding ion-beam-induced genetic mutation. Tens-keV Ar- and N-ion beams were decelerated to ultra-low energy ranging from 20 to 100 eV, or only a few to 10 eV/u, to bombard naked plasmid DNA. The bombarded DNA was analyzed using gel electrophoresis for DNA form changes. The original DNA supercoiled form was found to change to relaxed and linear forms, indicating single or double strand breaks after bombarded by tens-eV ion beam. N-ion beam was found more effective in inducing DNA change and mutation than Ar-ion beam. The study demonstrated that the ion bombardment with energy as low as several-tens eV was able to break DNA strands and thus potentially to cause genetic modification of biological cells. The experimental results were discussed in terms of direct atomic collision between the ions and DNA atoms.

Ultra-low-energy (<10 eV/u) ion beam bombardment effect on naked DNA

International Nuclear Information System (INIS)

Thopan, P.; Thongkumkoon, P.; Prakrajang, K.; Suwannakachorn, D.; Yu, L.D.

2014-01-01

Highlights: • Decelerated ultra-low energy ion beam bombarded naked DNA. • DNA form change induced by ion bombardment was investigated. • N-ion bombardment at 32 eV induced DNA single and double strand breaks. • Ar-ion bombardment at a-few-hundreds eV induced DNA single strand break. - Abstract: Since ion energy deposition in the ion-bombarded materials dominantly occurs in the low-energy range, it is very interesting to know effects from ultra-low-energy ion interaction with DNA for understanding ion-beam-induced genetic mutation. Tens-keV Ar- and N-ion beams were decelerated to ultra-low energy ranging from 20 to 100 eV, or only a few to 10 eV/u, to bombard naked plasmid DNA. The bombarded DNA was analyzed using gel electrophoresis for DNA form changes. The original DNA supercoiled form was found to change to relaxed and linear forms, indicating single or double strand breaks after bombarded by tens-eV ion beam. N-ion beam was found more effective in inducing DNA change and mutation than Ar-ion beam. The study demonstrated that the ion bombardment with energy as low as several-tens eV was able to break DNA strands and thus potentially to cause genetic modification of biological cells. The experimental results were discussed in terms of direct atomic collision between the ions and DNA atoms

Quantifying the Value of Hydropower in the Electric Grid. Final Report

Energy Technology Data Exchange (ETDEWEB)

Key, T. [Energy Efficiency and Renewable Energy (EERE), Washington, DC (United States)

2013-02-01

The report summarizes a 3-year DOE study focused on defining value of hydropower assets in a changing electric grid. The study looked at existing large hydropower operations in the U.S., models for different electricity futures, markets, costs of existing and new technologies as well as trends related to hydropower investments in other parts of the world.

Gross greenhouse gas fluxes from hydro-power reservoir compared to thermo-power plants

International Nuclear Information System (INIS)

Santos, Marco Aurelio dos; Pinguelli Rosa, Luiz; Sikar, Bohdan; Sikar, Elizabeth; Santos, Ednaldo Oliveira dos

2006-01-01

This paper presents the findings of gross carbon dioxide and methane emissions measurements in several Brazilian hydro-reservoirs, compared to thermo power generation. The term 'gross emissions' means gas flux measurements from the reservoir surface without natural pre-impoundment emissions by natural bodies such as the river channel, seasonal flooding and terrestrial ecosystems. The net emissions result from deducting pre-existing emissions by the reservoir. A power dam emits biogenic gases such as CO 2 and CH 4 . However, studies comparing gas emissions (gross emissions) from the reservoir surface with emissions by thermo-power generation technologies show that the hydro-based option presents better results in most cases analyzed. In this study, measurements were carried in the Miranda, Barra Bonita, Segredo, Tres Marias, Xingo, and Samuel and Tucurui reservoirs, located in two different climatological regimes. Additional data were used here from measurements taken at the Itaipu and Serra da Mesa reservoirs. Comparisons were also made between emissions from hydro-power plants and their thermo-based equivalents. Bearing in mind that the estimated values for hydro-power plants include emissions that are not totally anthropogenic, the hydro-power plants studied generally posted lower emissions than their equivalent thermo-based counterparts. Hydro-power complexes with greater power densities (capacity/area flooded-W/m 2 ), such as Itaipu, Xingo, Segredo and Miranda, have the best performance, well above thermo-power plants using state-of-the-art technology: combined cycle fueled by natural gas, with 50% efficiency. On the other hand, some hydro-power complexes with low-power density perform only slightly better or even worse than their thermo-power counterparts

Advanced hydropower turbine: AHTS-Advanced Hydropower Turbine System Program; Turbinas hidraulicas avancadas: Programa AHTS-Advanced Hydropower Turbine System

Energy Technology Data Exchange (ETDEWEB)

Macorin, Adriano De Figueiredo; Tomisawa, Alessandra Terumi; Van Deursen, Gustavo Jose Ferreira; Bermann, Celio [Universidade de Sao Paulo (USP), SP (Brazil)], email: brunosilva@usp.br

2010-07-01

Due to a privileged hydrography and energy policies that remounts to the beginning of the 20th century, Brazilian's electrical grid can be considered one of the cleanest in the world regarding the emission of atmospheric pollutants. Nevertheless, as in every human large enterprise, it is well known that hydroelectric power plants also lead to harmful environmental impacts. This article presents the AHTS Program (Advanced Hydropower Turbine System) started in 1994 in USA and developed to assess and conceive new hydro turbines to mitigate two of the main negative impacts of the installation and operation of this kind of power plant: (a) turbine-passed fish mortality and (b) the low dissolved oxygen - DO - levels downstream of the dams. The criteria used to concept the turbines are also justified in this article. As well as the modifications made in each case by the following companies: Alden Research Lab e o Northern Research and Engineering Corporation (ARL/NREC) and Voith Hydro (Voith). (author)

The influence of climate change on Tanzania's hydropower sustainability

Science.gov (United States)

Sperna Weiland, Frederiek; Boehlert, Brent; Meijer, Karen; Schellekens, Jaap; Magnell, Jan-Petter; Helbrink, Jakob; Kassana, Leonard; Liden, Rikard

2015-04-01

Economic costs induced by current climate variability are large for Tanzania and may further increase due to future climate change. The Tanzanian National Climate Change Strategy addressed the need for stabilization of hydropower generation and strengthening of water resources management. Increased hydropower generation can contribute to sustainable use of energy resources and stabilization of the national electricity grid. To support Tanzania the World Bank financed this study in which the impact of climate change on the water resources and related hydropower generation capacity of Tanzania is assessed. To this end an ensemble of 78 GCM projections from both the CMIP3 and CMIP5 datasets was bias-corrected and down-scaled to 0.5 degrees resolution following the BCSD technique using the Princeton Global Meteorological Forcing Dataset as a reference. To quantify the hydrological impacts of climate change by 2035 the global hydrological model PCR-GLOBWB was set-up for Tanzania at a resolution of 3 minutes and run with all 78 GCM datasets. From the full set of projections a probable (median) and worst case scenario (95th percentile) were selected based upon (1) the country average Climate Moisture Index and (2) discharge statistics of relevance to hydropower generation. Although precipitation from the Princeton dataset shows deviations from local station measurements and the global hydrological model does not perfectly reproduce local scale hydrographs, the main discharge characteristics and precipitation patterns are represented well. The modeled natural river flows were adjusted for water demand and irrigation within the water resources model RIBASIM (both historical values and future scenarios). Potential hydropower capacity was assessed with the power market simulation model PoMo-C that considers both reservoir inflows obtained from RIBASIM and overall electricity generation costs. Results of the study show that climate change is unlikely to negatively affect the

Using Conventional Hydropower to Help Alleviate Variable Resource Grid Integration Challenges in the Western U.S

Science.gov (United States)

Veselka, T. D.; Poch, L.

2011-12-01

Integrating high penetration levels of wind and solar energy resources into the power grid is a formidable challenge in virtually all interconnected systems due to the fact that supply and demand must remain in balance at all times. Since large scale electricity storage is currently not economically viable, generation must exactly match electricity demand plus energy losses in the system as time unfolds. Therefore, as generation from variable resources such as wind and solar fluctuate, production from generating resources that are easier to control and dispatch need to compensate for these fluctuations while at the same time respond to both instantaneous change in load and follow daily load profiles. The grid in the Western U.S. is not exempt to grid integration challenges associated with variable resources. However, one advantage that the power system in the Western U.S. has over many other regional power systems is that its footprint contains an abundance of hydropower resources. Hydropower plants, especially those that have reservoir water storage, can physically change electricity production levels very quickly both via a dispatcher and through automatic generation control. Since hydropower response time is typically much faster than other dispatchable resources such as steam or gas turbines, it is well suited to alleviate variable resource grid integration issues. However, despite an abundance of hydropower resources and the current low penetration of variable resources in the Western U.S., problems have already surfaced. This spring in the Pacific Northwest, wetter than normal hydropower conditions in combination with transmission constraints resulted in controversial wind resource shedding. This action was taken since water spilling would have increased dissolved oxygen levels downstream of dams thereby significantly degrading fish habitats. The extent to which hydropower resources will be able to contribute toward a stable and reliable Western grid is

Ultra-low-frequency dust-electromagnetic modes in self-gravitating magnetized dusty plasmas

International Nuclear Information System (INIS)

Mamun, A.A.

1999-07-01

Obliquely propagating ultra-low-frequency dust-electromagnetic waves in a self-gravitating, warm, magnetized two fluid dusty plasma system have been investigated. Two special cases, namely, dust-Alfven mode propagating parallel to the external magnetic field and dust-magnetosonic mode propagating perpendicular to the external magnetic field have also been considered. It has been shown that effects of self-gravitational field, dust fluid temperature, and obliqueness significantly modify the dispersion properties of these ultra-low-frequency dust-electromagnetic modes. It is also found that these effects of self-gravitational field and dust/ion fluid temperature play no role in parallel propagating dust-Alfven mode, but in obliquely propagating dust-Alfven mode or perpendicular propagating dust-magnetosonic mode the effect of self-gravitational field plays a destabilizing role whereas the effect of dust/ion fluid temperature plays a stabilizing role. (author)

Hydropower scene: boost for Dominican power supply

Energy Technology Data Exchange (ETDEWEB)

1988-12-01

When it is completed in 1991, the 150 MW Jiguey-Aguacate multi-purpose hydropower scheme will be the largest hydro project in the Dominican Republic. Construction of the scheme was recommended as a result of various studies carried out by the Instituto Nacional de Recursos Hidraulicos (INDHRI), which examined the hydropower potential of the Niazo river. Work is now in progress on site, with commissioning of the first unit expected in 1990.

DOE Hydropower Program biennial report 1996-1997 (with an updated annotated bibliography)

Energy Technology Data Exchange (ETDEWEB)

Rinehart, B.N.; Francfort, J.E.; Sommers, G.L. [Lockheed Idaho Technologies Co., Idaho Falls, ID (United States); Cada, G.F.; Sale, M.J. [Oak Ridge National Lab., TN (United States)

1997-06-01

This report, the latest in a series of biennial Hydropower Program reports sponsored by the US Department of Energy, summarizes the research and development and technology transfer activities of fiscal years 1996 and 1997. The report discusses the activities in the six areas of the hydropower program: advanced hydropower turbine systems; environmental research; hydropower research and development; renewable Indian energy resources; resource assessment; and technology transfer. The report also includes an annotated bibliography of reports pertinent to hydropower, written by the staff of the Idaho National Engineering and Environmental Laboratory, Oak Ridge National Laboratory, Federal and state agencies, cities, metropolitan water districts, irrigation companies, and public and independent utilities. Most reports are available from the National Technical Information Service.

[Electric traction magnetic fields of ultra-low frequency as an occupational risk factor of ischemic heart disease].

Science.gov (United States)

Ptitsyna, N G; Kudrin, V A; Villorezi, D; Kopytenko, Iu A; Tiasto, M I; Kopytenko, E A; Bochko, V A; Iuchchi, N

1996-01-01

The study was inspired by earlier results that displayed influence of variable natural geomagnetic field (0.005-10 Hz range-ultra-low frequencies) on circulatory system, indicated possible correlation between industrial ultra-low frequency fields and prevalence of myocardial infarction. The authors conducted unique measurements of ultra-low frequency fields produced by electric engines. The results were compared with data on morbidity among railway transport workers. The findings are that level of magnetic variations in electric locomotive cabin can exceed 280 micro Tesla, whereas that in car sections reaches 50 micro Tesla. Occurrence of coronary heart disease among the locomotive operators appeared to be 2.0 + 0.2 times higher than that among the car section operators. Higher risk of coronary heart disease in the locomotive operators is associated with their increased occupational magnetic load.

78 FR 55251 - Hydropower Regulatory Efficiency Act of 2013; Notice of Workshop

Science.gov (United States)

2013-09-10

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. AD13-9-000] Hydropower... hydropower development at non-powered dams and closed-loop pumped storage projects in compliance with section 6 of the Hydropower Regulatory Efficiency Act of 2013. Participants should be prepared to discuss...

Ultra-Low Inductance Design for a GaN HEMT Based 3L-ANPC Inverter

DEFF Research Database (Denmark)

Gurpinar, Emre; Castellazzi, Alberto; Iannuzzo, Francesco

2016-01-01

contributors to voltage overshoots and increase of switching losses, are discussed. The ultra-low inductance power cell design based on a four layer PCB with the aim to maximise the switching performance of GaN HEMTs is explained. Gate driver design for GaN HEMT devices is presented. Common-mode behaviours......In this paper, an ultra-low inductance power cell design for a 3L-ANPC based on 650 V GaN HEMT devices is presented. The 3L-ANPC topology with GaN HEMT devices and the selected modulation scheme suitable for wide-bandgap (WBG) devices are presented. The commutation loops, which are the main...

Fuzzy rule-based model for hydropower reservoirs operation

Energy Technology Data Exchange (ETDEWEB)

Moeini, R.; Afshar, A.; Afshar, M.H. [School of Civil Engineering, Iran University of Science and Technology, Tehran (Iran, Islamic Republic of)

2011-02-15

Real-time hydropower reservoir operation is a continuous decision-making process of determining the water level of a reservoir or the volume of water released from it. The hydropower operation is usually based on operating policies and rules defined and decided upon in strategic planning. This paper presents a fuzzy rule-based model for the operation of hydropower reservoirs. The proposed fuzzy rule-based model presents a set of suitable operating rules for release from the reservoir based on ideal or target storage levels. The model operates on an 'if-then' principle, in which the 'if' is a vector of fuzzy premises and the 'then' is a vector of fuzzy consequences. In this paper, reservoir storage, inflow, and period are used as premises and the release as the consequence. The steps involved in the development of the model include, construction of membership functions for the inflow, storage and the release, formulation of fuzzy rules, implication, aggregation and defuzzification. The required knowledge bases for the formulation of the fuzzy rules is obtained form a stochastic dynamic programming (SDP) model with a steady state policy. The proposed model is applied to the hydropower operation of ''Dez'' reservoir in Iran and the results are presented and compared with those of the SDP model. The results indicate the ability of the method to solve hydropower reservoir operation problems. (author)

A GIS based assessment of hydropower potential in Hornád basin

Directory of Open Access Journals (Sweden)

�ofia Kuzevičová

2013-12-01

Full Text Available The issue of efficient use of hydropower, ones of the available renewable resources is currently in the process of sustainable development of each country, often addressing the issue. Incite multiple aspects. It is now seen just growing interest in exploiting the potential of hydropower. On the basis of active efforts are developed to map the total quantity of usability hydropower at basin level in Slovakia. GIS as a powerful and sophisticated tool for processing spatially localized information and offers support for renewable energy sources (not excluding the field of hydropower. Through the integration of spatial data allows assessing the real problems and thus contributing effectively to make rational decisions. Especially in the field of hydropower projects have GIS well founded importance. Of course is important to mention that the potential for hydroelectric power is useless without the operation of hydropower that converts water into electrical energy. For the needs of administrators of watercourses and operators of water systems, the proposed model can be an important tool for decision-making in relation to its implementation activities. Contribution to the design solutions for potential hydropower will address river basin Hornád.

Sun Ultra 5

CERN Multimedia

1998-01-01

The Sun Ultra 5 is a 64-bit personal computer based on the UltraSPARC microprocessor line at a low price. The Ultra 5 has been declined in several variants: thus, some models have a processor with less cache memory to further decrease the price of the computer.

Sustainability of hydropower as source of renewable and clean energy

International Nuclear Information System (INIS)

Luis, J; Sidek, L M; Desa, M N M; Julien, P Y

2013-01-01

Hydroelectric energy has been in recent times placed as an important future source of renewable and clean energy. The advantage of hydropower as a renewable energy is that it produces negligible amounts of greenhouse gases, it stores large amounts of electricity at low cost and it can be adjusted to meet consumer demand. This noble vision however is becoming more challenging due to rapid urbanization development and increasing human activities surrounding the catchment area. Numerous studies have shown that there are several contributing factors that lead towards the loss of live storage in reservoir, namely geology, ground slopes, climate, drainage density and human activities. Sediment deposition in the reservoir particularly for hydroelectric purposes has several major concerns due to the reduced water storage volume which includes increase in the risk of flooding downstream which directly effects the safety of human population and properties, contributes to economic losses not only in revenue for power generation but also large capital and maintenance cost for reservoir restorations works. In the event of functional loss of capabilities of a hydropower reservoir as a result of sedimentation or siltation could lead to both economical and environmental impact. The objective of this paper is aimed present the importance of hydropower as a source of renewable and clean energy in the national energy mix and the increasing challenges of sustainability.

Hydropower development in the Philippines

International Nuclear Information System (INIS)

Lopez, P.L.

1997-01-01

The present policy on energy development is geared towards harnessing renewable and indigenous energy resource which can offer clean, abundant and efficient power supply for the country. a review of the current generation mix of the power system, especially the Luzon grid will establish a high dependency in imported fuel - oil and coal to power our generating plants. Thus, the policy of reducing dependence on imported fuel will depend largely on the success of tapping the alternative renewable and indigenous sources. The sustainable development era of the 90's brought fresh interest on the performance and commercial viability of indigenous and/or renewable sources of energy such as wind, solar, geothermal, natural gas and water power or hydropower. Among these alternative renewable sources, water or hydropower is the most readily available, and will produce clean domestic source of electricity - no carbon dioxide, sulfur dioxide, nitrous oxide or any other air emissions. The potential is available in most parts of the country that are mountainous and have high rainfall. In terms of production, hydropower leads as the most developed and more proven in terms of commercial viability. It is also more reliable, efficient and less expensive than geothermal, biomass, wind and solar energy, as will be shown later. (author)

Ultra Low Friction of DLC Coating with Lubricant

International Nuclear Information System (INIS)

Kano, M; Yoshida, K

2010-01-01

The objective of this study was to find a trigger to make clear a mechanism of the ultra low friction by evaluating the friction property of DLC-DLC combination under lubrication with the simple fluid. The Pin-on-disc reciprocating and rotating sliding tests were conducted to evaluate the friction property. The super low friction property of pure sliding with the ta-C(T) pair coated by the filtered arc deposition process under oleic acid lubrication was found at the mixed lubrication condition. It was thought that the low share strength tribofilm composed of water and acid seemed to be formed on ta-C sliding interface. Additionally, the smooth sliding surface formed on ta-C(T) was seemed to be required to keep this tribofilm. Then, the super low friction was thought to be obtained by this superlubrication condition. Although the accurate and direct experimental data must be required to make clear this super low friction mechanism, the advanced effect obtained by the simple material combination is expected to be applied on the large industrial fields in near future.

Integrating Economic and Ecological Benchmarking for a Sustainable Development of Hydropower

Directory of Open Access Journals (Sweden)

Philipp Emanuel Hirsch

2016-08-01

Full Text Available Hydropower reservoirs play an increasingly important role for the global electricity supply. Reservoirs are anthropogenically-dominated ecosystems because hydropower operations induce artificial water level fluctuations (WLF that exceed natural fluctuations in frequency and amplitude. These WLF have detrimental ecological effects, which can be quantified as losses to ecosystem primary production due to lake bottoms that fall dry. To allow for a sustainable development of hydropower, these “ecological costs” of WLF need to be weighed against the “economic benefits” of hydropower that can balance and store intermittent renewable energy. We designed an economic hydropower operation model to derive WLF in large and small reservoirs for three different future energy market scenarios and quantified the according losses in ecosystem primary production in semi-natural outdoor experiments. Our results show that variations in market conditions affect WLF differently in small and large hydropower reservoirs and that increasing price volatility magnified WLF and reduced primary production. Our model allows an assessment of the trade-off between the objectives of preserving environmental resources and economic development, which lies at the core of emerging sustainability issues.

Developing hydropower overseas

International Nuclear Information System (INIS)

Smith, W.B.

1991-01-01

This article examines how the National Hydropower Association (NHA) has found ways to support its members who desire to expand their business programs to foreign markets through participation in a wide range of government programs. The topics of the article include the market in developing countries, the certificate of review, products and services, and domestic and international competition

Hydropower systems planning in distribution networks based on GIS

Energy Technology Data Exchange (ETDEWEB)

Ramirez-Rosado, I.J.; Zorzano-Santamaria, P.; Fernandez-Jiminez, L.A.; Garcia-Garrido, E.; Zorzano-Alba, E.; Lara-Santillan, P.M.; Mendoza-Villena, M. [La Rioja Univ., La Rioja (Spain). Dept. of Electrical Engineering

2005-07-01

Planning models for hydraulic energy systems developed with a new computational geographic information system (GIS) tool were presented. The GIS tool was used to identify sections of rivers that are suitable for small-scale run-of-river hydropower generation in the La Rioja region of Spain. The tool was also used to evaluate economic data related to financing grants, technological costs, installation costs, and forecast demands for various consumption scenarios. Case studies of 2 hydropower systems were used to test the tool. The planning models were based on levelized electric costs (LEC) of run-of-river hydropower systems, and enabled the systems to be analyzed in isolation as well as when connected to an existing electricity network. Results of the modelling studies showed that the tool is capable of analyzing the LEC of potential hydropower systems in a range of different scenarios while maintaining the geographic characteristics and requirements of individual regions. 7 refs., 4 figs.

Hydropower in the Southeast: Balancing Lakeview and Production Optimization

Science.gov (United States)

Engstrom, J.

2017-12-01

Hydropower is the most important source of renewable electricity in Southeastern U.S. However, the region is repeatedly struck by droughts, and there are many conflicting interests in the limited water resource. This study takes a historical perspective and investigates how hydropower production patterns have changed over time, considering both natural drivers and human dimensions. Hydropower production is strongly tied to the natural variability of large-scale atmospheric drivers (teleconnections) as they affect the water availability in the whole river system and partly also the market demand. To balance the water resource between different interests is a complex task, and the conflicting interests vary by basin, sometimes over a relatively small geographic area. Here road networks adjacent to the hydropower reservoirs are used as an indicator of human development and recreational activities. Through a network analysis of the historical development of road networks surrounding the reservoir, the local and regional conflicting interests are identified and the influence on renewable electricity production quantified.

Managing Financial Risk to Hydropower in Snow Dominated Systems: A Hetch Hetchy Case Study

Science.gov (United States)

Hamilton, A. L.; Characklis, G. W.; Reed, P. M.

2017-12-01

Hydropower generation in snow dominated systems is vulnerable to severe shortfalls in years with low snowpack. Meanwhile, generators are also vulnerable to variability in electricity demand and wholesale electricity prices, both of which can be impacted by factors such as temperature and natural gas price. Year-to-year variability in these underlying stochastic variables leads to financial volatility and the threat of low revenue periods, which can be highly disruptive for generators with large fixed operating costs and debt service. In this research, the Hetch Hetchy Power system is used to characterize financial risk in a snow dominated hydropower system. Owned and operated by the San Francisco Public Utilities Commission, Hetch Hetchy generates power for its own municipal operations and sells excess power to irrigation districts, as well as on the wholesale market. This investigation considers the effects of variability in snowpack, temperature, and natural gas price on Hetch Hetchy Power's yearly revenues. This information is then used to evaluate the effectiveness of various financial risk management tools for hedging against revenue variability. These tools are designed to mitigate against all three potential forms of financial risk (i.e. low hydropower generation, low electricity demand, and low/high electricity price) and include temperature-based derivative contracts, natural gas price-based derivative contracts, and a novel form of snowpack-based index insurance contract. These are incorporated into a comprehensive risk management portfolio, along with self-insurance in which the utility buffers yearly revenue volatility using a contingency fund. By adaptively managing the portfolio strategy, a utility can efficiently spread yearly risks over a multi-year time horizon. The Borg Multiobjective Evolutionary Algorithm is used to generate a set of Pareto optimal portfolio strategies, which are used to compare the tradeoffs in objectives such as expected

Interactions between land use, climate and hydropower in Scotland

Science.gov (United States)

Sample, James

2015-04-01

To promote the transition towards a low carbon economy, the Scottish Government has adopted ambitious energy targets, including generating all electricity from renewable sources by 2020. To achieve this, continued investment will be required across a range of sustainable technologies. Hydropower has a long history in Scotland and the present-day operational capacity of ~1.5 GW makes a substantial contribution to the national energy budget. In addition, there remains potential for ~500 MW of further development, mostly in the form of small to medium size run-of-river schemes. Climate change is expected to lead to an intensification of the global hydrological cycle, leading to changes in both the magnitude and seasonality of river flows. There may also be indirect effects, such as changing land use, enhanced evapotranspiration rates and an increased demand for irrigation, all of which could affect the water available for energy generation. Preliminary assessments of hydropower commonly use flow duration curves (FDCs) to estimate the power generation potential at proposed new sites. In this study, we use spatially distributed modelling to generate daily and monthly FDCs on a 1 km by 1 km grid across Scotland, using a variety of future land use and climate change scenarios. Parameter-related uncertainty in the model has been constrained using Bayesian Markov Chain Monte Carlo (MCMC) techniques to derive posterior probability distributions for key model parameters. Our results give an indication of the sensitivity and vulnerability of Scotland's run-of-river hydropower resources to possible changes in climate and land use. The effects are spatially variable and the range of uncertainty is sometimes large, but consistent patterns do emerge. For example, many locations are predicted to experience enhanced seasonality, with significantly lower power generation potential in the summer months and greater potential during the autumn and winter. Some sites may require

On the low frequency characteristics of head-related transfer function

Institute of Scientific and Technical Information of China (English)

XIE Bosun

2009-01-01

A method to correct the measured head-related transfer functions (HRTFs) at low frequency was proposed. By analyzing the HRTFs from the spherical head model at low frequency, it is proved that below the frequency of 400 Hz, magnitude of HRTF is nearly constant and the phase is a linear function of frequency both for the far and near field. Therefore, if the HRTFs above 400 Hz are accurately measured by experiment, it is able to correct the HRTFs at low frequency by the theoretical model. The results of calculation and subjective experiment show that the feasibility of the proposed method.

Hydropower: Partnership with the Environment

Energy Technology Data Exchange (ETDEWEB)

None

2001-06-01

This brochure provides useful information on types of hydroelectric facilities as well as general information on capacity, generation, environmental issues, and advanced conventional hydropower technology within the United States.

Virtual Colonoscopy Screening With Ultra Low-Dose CT and Less-Stressful Bowel Preparation: A Computer Simulation Study

Science.gov (United States)

Wang, Jing; Wang, Su; Li, Lihong; Fan, Yi; Lu, Hongbing; Liang, Zhengrong

2008-10-01

Computed tomography colonography (CTC) or CT-based virtual colonoscopy (VC) is an emerging tool for detection of colonic polyps. Compared to the conventional fiber-optic colonoscopy, VC has demonstrated the potential to become a mass screening modality in terms of safety, cost, and patient compliance. However, current CTC delivers excessive X-ray radiation to the patient during data acquisition. The radiation is a major concern for screening application of CTC. In this work, we performed a simulation study to demonstrate a possible ultra low-dose CT technique for VC. The ultra low-dose abdominal CT images were simulated by adding noise to the sinograms of the patient CTC images acquired with normal dose scans at 100 mA s levels. The simulated noisy sinogram or projection data were first processed by a Karhunen-Loeve domain penalized weighted least-squares (KL-PWLS) restoration method and then reconstructed by a filtered backprojection algorithm for the ultra low-dose CT images. The patient-specific virtual colon lumen was constructed and navigated by a VC system after electronic colon cleansing of the orally-tagged residue stool and fluid. By the KL-PWLS noise reduction, the colon lumen can successfully be constructed and the colonic polyp can be detected in an ultra low-dose level below 50 mA s. Polyp detection can be found more easily by the KL-PWLS noise reduction compared to the results using the conventional noise filters, such as Hanning filter. These promising results indicate the feasibility of an ultra low-dose CTC pipeline for colon screening with less-stressful bowel preparation by fecal tagging with oral contrast.

A Holistic Framework for Environmental Flows Determination in Hydropower Contexts

Energy Technology Data Exchange (ETDEWEB)

McManamay, Ryan A [ORNL; Bevelhimer, Mark S [ORNL

2013-05-01

Among the ecological science community, the consensus view is that the natural flow regime sustains the ecological integrity of river systems. This prevailing viewpoint by many environmental stakeholders has progressively led to increased pressure on hydropower dam owners to change plant operations to affect downstream river flows with the intention of providing better conditions for aquatic biological communities. Identifying the neccessary magnitude, frequency, duration, timing, or rate of change of stream flows to meet ecological needs in a hydropower context is challenging because the ecological responses to changes in flows may not be fully known, there are usually a multitude of competing users of flow, and implementing environmental flows usually comes at a price to energy production. Realistically, hydropower managers must develop a reduced set of goals that provide the most benefit to the identified ecological needs. As a part of the Department of Energy (DOE) Water Power Program, the Instream Flow Project (IFP) was carried out by Oak Ridge National Laboratory (ORNL), Pacific Northwest National Laboratory (PNNL), and Argon National Laboratory (ANL) as an attempt to develop tools aimed at defining environmental flow needs for hydropower operations. The application of these tools ranges from national to site-specific scales; thus, the utility of each tool will depend on various phases of the environmental flow process. Given the complexity and sheer volume of applications used to determine environmentally acceptable flows for hydropower, a framework is needed to organize efforts into a staged process dependent upon spatial, temporal, and functional attributes. By far, the predominant domain for determining environmental flows related to hydropower is within the Federal Energy Regulatory Commission (FERC) relicensing process. This process can take multiple years and can be very expensive depending on the scale of each hydropower project. The utility of such a

Convolutional auto-encoder for image denoising of ultra-low-dose CT

Directory of Open Access Journals (Sweden)

Mizuho Nishio

2017-08-01

Conclusion: Neural network with convolutional auto-encoder could be trained using pairs of standard-dose and ultra-low-dose CT image patches. According to the visual assessment by radiologists and technologists, the performance of our proposed method was superior to that of large-scale nonlocal mean and block-matching and 3D filtering.

Ultra low-cost, portable smartphone optosensors for mobile point-of-care diagnostics

Science.gov (United States)

Wang, Li-Ju; Chang, Yu-Chung; Sun, Rongrong; Li, Lei

2018-02-01

Smartphone optosensors with integrated optical components make mobile point-of-care (MPoC) diagnostics be done near patients' side. It'll especially have a significant impact on healthcare delivery in rural or remote areas. Current FDA-approved PoC devices achieving clinical level are still at high cost and not affordable in rural hospitals. We present a series of ultra low-cost smartphone optical sensing devices for mobile point-of-care diagnosis. Aiming different targeting analytes and sensing mechanisms, we developed custom required optical components for each smartphone optosensros. These optical devices include spectrum readers, colorimetric readers for microplate, lateral flow device readers, and chemiluminescence readers. By integrating our unique designed optical components into smartphone optosening platform, the anlaytes can be precisely detected. Clinical testing results show the clinical usability of our smartphone optosensors. Ultra low-cost portable smartphone optosensors are affordable for rural/remote doctors.

Construction and Evaluation of an Ultra Low Latency Frameless Renderer for VR.

Science.gov (United States)

Friston, Sebastian; Steed, Anthony; Tilbury, Simon; Gaydadjiev, Georgi

2016-04-01

Latency - the delay between a user's action and the response to this action - is known to be detrimental to virtual reality. Latency is typically considered to be a discrete value characterising a delay, constant in time and space - but this characterisation is incomplete. Latency changes across the display during scan-out, and how it does so is dependent on the rendering approach used. In this study, we present an ultra-low latency real-time ray-casting renderer for virtual reality, implemented on an FPGA. Our renderer has a latency of ~1 ms from 'tracker to pixel'. Its frameless nature means that the region of the display with the lowest latency immediately follows the scan-beam. This is in contrast to frame-based systems such as those using typical GPUs, for which the latency increases as scan-out proceeds. Using a series of high and low speed videos of our system in use, we confirm its latency of ~1 ms. We examine how the renderer performs when driving a traditional sequential scan-out display on a readily available HMO, the Oculus Rift OK2. We contrast this with an equivalent apparatus built using a GPU. Using captured human head motion and a set of image quality measures, we assess the ability of these systems to faithfully recreate the stimuli of an ideal virtual reality system - one with a zero latency tracker, renderer and display running at 1 kHz. Finally, we examine the results of these quality measures, and how each rendering approach is affected by velocity of movement and display persistence. We find that our system, with a lower average latency, can more faithfully draw what the ideal virtual reality system would. Further, we find that with low display persistence, the sensitivity to velocity of both systems is lowered, but that it is much lower for ours.

An empirical analysis of the hydropower portfolio in Pakistan

International Nuclear Information System (INIS)

Siddiqi, Afreen; Wescoat, James L.; Humair, Salal; Afridi, Khurram

2012-01-01

The Indus Basin of Pakistan with 800 hydropower project sites and a feasible hydropower potential of 60 GW, 89% of which is undeveloped, is a complex system poised for large-scale changes in the future. Motivated by the need to understand future impacts of hydropower alternatives, this study conducted a multi-dimensional, empirical analysis of the full hydropower portfolio. The results show that the full portfolio spans multiple scales of capacity from mega (>1000 MW) to micro (<0.1 MW) projects with a skewed spatial distribution within the provinces, as well as among rivers and canals. Of the total feasible potential, 76% lies in two (out of six) administrative regions and 68% lies in two major rivers (out of more than 125 total channels). Once projects currently under implementation are commissioned, there would be a five-fold increase from a current installed capacity of 6720 MW to 36759 MW. It is recommended that the implementation and design decisions should carefully include spatial distribution and environmental considerations upfront. Furthermore, uncertainties in actual energy generation, and broader hydrological risks due to expected climate change effects should be included in the current planning of these systems that are to provide service over several decades into the future. - Highlights: ► Pakistan has a hydropower potential of 60 GW distributed across 800 projects. ► Under-development projects will realize 36.7 GW of this potential by 2030. ► Project locations are skewed towards some sub-basins and provinces. ► Project sizes are very diverse and have quite limited private sector ownership. ► Gaps in data prevent proper risk assessment for Pakistan's hydropower development.

Hydropower Impacts on Electrical System Production Costs in the Southwest United States

Directory of Open Access Journals (Sweden)

Dominique M. Bain

2018-02-01

Full Text Available The Colorado River is an important natural resource for the Southwestern United States. Predicted climate change impacts include increased temperature, decreased rainfall and increased probability of drought in this region. Given the large amount of hydropower on the Colorado River and its importance to the bulk electricity system, this purpose of this study was to quantify the value hydropower in operating the electrical system, and examined changes in hydropower value and electricity costs under different possible future drought conditions and regional generation scenarios. The goal was to better understand how these scenarios affect operating costs of the bulk electrical system, as well as the value of the hydropower produced, and proposed a method for doing so. The calculated value of the hydroelectric power was nearly double the mean locational marginal price in the study area, about $73 to $75 for most scenarios, demonstrating a high value of the hydropower. In general, it was found that reduced water availability increased operating costs, and increased the value of the hydropower. A calculated value factor showed that when less hydroelectric power is available, the hydropower is more valuable. Furthermore, the value factor showed that the value of hydro increases with the addition of solar or the retirement of thermal generating resources.

Accelerating Sustainability by Hydropower Development in China: The Story of HydroLancang

Directory of Open Access Journals (Sweden)

Yan Zhang

2017-07-01

Full Text Available Sustainable development is a shared responsibility. Accelerating sustainability of water–energy–people nexus and building a common awareness of issues pertaining to sustainable development are essential for any sort of success in this direction. Hydropower has been a useful sustainable energy for development, yet highly controversial. This paper reviews the overall situation of hydropower development and China’s energy reforms and policies, accompanied with a case study of hydropower development the Lancang River by the HydroLancang, aiming to illustrate the two opposite sides of hydropower development—economy and environment. The paper concludes with a neutral view of hydropower as the necessary facilitator for development. Water is a shared responsibility. Hydropower might not be the optimum solution to eliminate the tension between human demand of energy and finite natural resource and the rising pressure of climate change worldwide, but it serves well as an “Electricity Bridge” before better alternatives become available. This is a more balanced view of hydropower rather than two extreme viewpoints that present themselves: on the one hand, exaggerated claims of the human power to tame the wild river, and, on the other hand, the idealistic fantasy of preserving nature by abandoning all human activity.

77 FR 51551 - Proposed Renewal of Information Collection: Alternatives Process in Hydropower Licensing

Science.gov (United States)

2012-08-24

...: Alternatives Process in Hydropower Licensing AGENCY: Office of the Secretary, Office of Environmental Policy... approval for the collection of information for Alternatives Process in Hydropower Licensing. This... comments should reference Alternatives Process in Hydropower Licensing. FOR FURTHER INFORMATION CONTACT: To...

Renewable energy in the Baltic countries: the case of hydropower

International Nuclear Information System (INIS)

Punys, P.; Dumbrauskas, A.; Rimkus, Z.; Streimikiene, D.

2006-01-01

This paper analyses the use of renewable energy sources (RES) dedicated mainly for electricity generation in the Baltic countries (Estonia, Latvia and Lithuania). Hydropower sector including both large (medium) and small power plants is particularly considered. The region has very limited energy resources of its own and is heavily dependent on the import of the primary energy sources (in some way except Estonia). The main objective of energy policy of the Baltic countries is to reduce such a total dependence by favouring the use of RES. A brief description of energy sector is given, focusing on electricity generation. RES potential currently in use and to be exploited in the future, buy- back rates of the key sources are presented. The countries' target broken down according to the individual RES to meet the EU 'green' electricity directive (2001/77/CE) are presented. Small and large hydropower potential is analyzed, a general overview of hydro-plants in operation and planned schemes is provided. A particular attention is devoted to environmental and social aspects of hydropower development. The requirements of the protected areas in relation to dam construction are analyzed, an estimation of resistance to small hydropower development is shown. The environmental legislation including forbidden rivers for damming actually in force in the Baltic countries is considered; hydropower image perceptible by general public, NGOs and official environmental bodies are discussed. The causes and legal basis of the promulgation of the list of forbidden rivers are revealed. A conclusion is drawn that the contradiction between two EU legal frameworks - environmental protection and promotion of renewables, in the case of hydropower, exists. The evaluation of the quantitative impact of the forbidden rivers on small hydropower resources in Lithuania proves. the environmental legislation is one of the strictest in the European countries. (authors)

Ultra-high sensitive hydrazine chemical sensor based on low-temperature grown ZnO nanoparticles

International Nuclear Information System (INIS)

Mehta, S.K.; Singh, Kulvinder; Umar, Ahmad; Chaudhary, G.R.; Singh, Sukhjinder

2012-01-01

Graphical abstract: Systematic representation of the fabricated amperometric hydrazine chemical sensor based on ZnO NPs/Au modified electrode. Highlights: ► Synthesis of well-crystalline ZnO NPs has been achieved in aqueous solution. ► ZnO NPs act as efficient electron mediators for hydrazine sensor. ► Extremely high sensitivity and low-detection limit have been obtained. - Abstract: Using well-crystalline ZnO nanoparticles (NPs), an ultra high sensitive hydrazine amperometric sensor has been fabricated and reported in this paper. The ZnO NPs have been synthesized by very simple aqueous solution process at 90 °C and characterized in detail in terms of their morphological, compositional, structural and optical properties. The detailed investigations reveal that the synthesized products are well-crystalline NPs, possessing wurtzite hexagonal phase and exhibit good optical properties. The fabricated amperometric hydrazine sensor exhibits ultra-high sensitivity of ∼97.133 μA cm −2 μM −1 and very low-detection limit of 147.54 nM. To the best of our knowledge, this is the first report in which an ultra-high sensitivity and low-detection limit have been obtained for the hydrazine chemical sensor based on ZnO nanostructures.

Modeling Multi-Reservoir Hydropower Systems in the Sierra Nevada with Environmental Requirements and Climate Warming

Science.gov (United States)

Rheinheimer, David Emmanuel

Hydropower systems and other river regulation often harm instream ecosystems, partly by altering the natural flow and temperature regimes that ecosystems have historically depended on. These effects are compounded at regional scales. As hydropower and ecosystems are increasingly valued globally due to growing values for clean energy and native species as well as and new threats from climate warming, it is important to understand how climate warming might affect these systems, to identify tradeoffs between different water uses for different climate conditions, and to identify promising water management solutions. This research uses traditional simulation and optimization to explore these issues in California's upper west slope Sierra Nevada mountains. The Sierra Nevada provides most of the water for California's vast water supply system, supporting high-elevation hydropower generation, ecosystems, recreation, and some local municipal and agricultural water supply along the way. However, regional climate warming is expected to reduce snowmelt and shift runoff to earlier in the year, affecting all water uses. This dissertation begins by reviewing important literature related to the broader motivations of this study, including river regulation, freshwater conservation, and climate change. It then describes three substantial studies. First, a weekly time step water resources management model spanning the Feather River watershed in the north to the Kern River watershed in the south is developed. The model, which uses the Water Evaluation And Planning System (WEAP), includes reservoirs, run-of-river hydropower, variable head hydropower, water supply demand, and instream flow requirements. The model is applied with a runoff dataset that considers regional air temperature increases of 0, 2, 4 and 6 °C to represent historical, near-term, mid-term and far-term (end-of-century) warming. Most major hydropower turbine flows are simulated well. Reservoir storage is also

Calibration of an ultra-low-background proportional counter for measuring 37Ar

International Nuclear Information System (INIS)

Seifert, A.; Aalseth, C. E.; Bonicalzi, R. M.; Bowyer, T. W.; Day, A. R.; Fuller, E. S.; Haas, D. A.; Hayes, J. C.; Hoppe, E. W.; Humble, P. H.; Keillor, M. E.; LaFerriere, B. D.; Mace, E. K.; McIntyre, J. I.; Merriman, J. H.; Miley, H. S.; Myers, A. W.; Orrell, J. L.; Overman, C. T.; Panisko, M. E.

2013-01-01

An ultra-low-background proportional counter design has been developed at Pacific Northwest National Laboratory (PNNL) using clean materials, primarily electro-chemically-purified copper. This detector, along with an ultra-low-background counting system (ULBCS), was developed to complement a new shallow underground laboratory (30 meters water-equivalent) at PNNL. The ULBCS design includes passive neutron and gamma shielding, along with an active cosmic-veto system. This system provides a capability for making ultra-sensitive measurements to support applications like age-dating soil hydrocarbons with 14 C/ 3 H, age-dating of groundwater with 39 Ar, and soil-gas assay for 37 Ar to support On-Site Inspection (OSI). On-Site Inspection is a key component of the verification regime for the Comprehensive Nuclear-Test-Ban Treaty (CTBT). Measurements of radionuclides created by an underground nuclear explosion are valuable signatures of a Treaty violation. For OSI, the 35-day half-life of 37 Ar, produced from neutron interactions with calcium in soil, provides both high specific activity and sufficient time for inspection before decay limits sensitivity. This work describes the calibration techniques and analysis methods developed to enable quantitative measurements of 37 Ar samples over a broad range of proportional counter operating pressures. These efforts, along with parallel work in progress on gas chemistry separation, are expected to provide a significant new capability for 37 Ar soil gas background studies

77 FR 30308 - Proposed Renewal of Information Collection: Alternatives Process in Hydropower Licensing

Science.gov (United States)

2012-05-22

...: Alternatives Process in Hydropower Licensing AGENCY: Office of the Secretary, Office of Environmental Policy... the Alternatives Process in Hydropower Licensing, OMB Control Number 1094-0001. FOR FURTHER... more of the Departments develop for inclusion in a hydropower license issued by the Federal Energy...

Modelling the feasibility of retrofitting hydropower to existing South ...

African Journals Online (AJOL)

An investigation was carried out with the primary objective of ascertaining whether it is possible to develop a model for determining the feasibility of retrofitting hydropower to existing dams in South Africa. The need for such a model is primarily due to the growing importance of small-scale hydropower projects resulting from ...

75 FR 65620 - Inglis Hydropower, LLC; Notice of Application Ready for Environmental Analysis and Soliciting...

Science.gov (United States)

2010-10-26

... Hydropower, LLC; Notice of Application Ready for Environmental Analysis and Soliciting Comments...: Inglis Hydropower, LLC. e. Name of Project: Inglis Hydropower Project. f. Location: The project would be... ready for environmental analysis at this time. l. The proposed 2.0-megawatt Inglis Hydropower Project...

Damages and methods for reparation; Hydropower structures; Skador och reparationsmetoder

Energy Technology Data Exchange (ETDEWEB)

Sandstroem, Tomas

2008-10-15

As the focus of the Swedish Hydropower Industry shifted from the developing phase of the 20th century to the present phase of managing and maintenance of the hydropower plants and the adherent structures knowledge regarding issues concerning repair work and degradation processes of concrete has become truly important. Hydropower structures are submitted to live loads (for example caused by ice, water, snow and wind) and physical attacks such as Freeze/thaw, leaching and erosion (abrasion and cavitation). Hydropower structures are also submitted to chemical and electro chemical attacks like ASR and corrosion of the reinforcement bars. All of the mentioned processes have a negative affect on concrete structures service life. As it is today the Hydropower Industry possesses a rather high degree of knowledge concerning principal repair and strengthening techniques like shotcreting and grouting. The purpose of this report is (1) to point out the Swedish Hydropower Industry's need for extensive knowledge regarding overlays and toppings and (2) the potential advantages of overlays and toppings as repair techniques with respect to hydropower environments and the corresponding degradation processes acting on those structures. The performance of repairing a concrete structure using overlays or toppings is principally executed by the removal (totally or partially) of the damaged concrete surface, afterwards a new concrete overlay or topping is applied. The overlay must be able to withstand the live loads and the physical, chemical and electro-chemical attacks that are acting on the structure. The overlay is also required to co-operate with, and protect, the host material for a very long time. This report deals with the most common types of physical and chemical processes that are acting in Hydropower environments and the damages that they are causing concrete structures. Some of the common principal repair techniques that can be used when repairing the damaged concrete

An ultra low-power off-line APDM-based switchmode power supply with very high conversion efficiency

DEFF Research Database (Denmark)

Nielsen, Nils

2001-01-01

This article describes the results from the research work on design of a ultra low power off-line power supply with very high conversion efficiency. The input voltage is 230 VAC nominal and output voltage is 5 VDC. By ultra low power levels, an output power level in the area ranging from 50 m......W and up to 1000 mW is meant. The small power supply is intended for use as a standby power supply in mains operated equipment, which requires a small amount of power in standby mode....

Hydropower is not plain sailing all the way

International Nuclear Information System (INIS)

De Vries, E.

1991-01-01

A report is given of the conference Hidroenergia 1991, which was held in Nice, France, from 12 to 15 June. The author highlights the subjects on the problems of implementing hydro-power, and the environmental effects of the use of hydro-power. Special attention is paid to the activities of the European Community to limit the constraints, which form hindrances to the development of hydroelectric power. 2 ills., 3 refs

Optimization of ultra-low-power CMOS transistors

International Nuclear Information System (INIS)

Stockinger, M.

2000-01-01

Ultra-low-power CMOS integrated circuits have constantly gained importance due to the fast growing portable electronics market. High-performance applications like mobile telephones ask for high-speed computations and low stand-by power consumption to increase the actual operating time. This means that transistors with low leakage currents and high drive currents have to be provided. Common fabrication methods will soon reach their limits if the on-chip feature size of CMOS technology continues to shrink at this very fast rate. New device architectures will help to keep track with the roadmap of the semiconductor industry. Especially doping profiles offer much freedom for performance improvements as they determine the 'inner functioning' of a transistor. In this work automated doping profile optimization is performed on MOS transistors within the TCAD framework SIESTA. The doping between and under the source/drain wells is discretized on an orthogonal optimization grid facilitating almost arbitrary two-dimensional shapes. A linear optimizer issued to find the optimum doping profile by variation of the doping parameters utilizing numerical device simulations with MINIMOS-NT. Gaussian functions are used in further optimization runs to make the doping profiles smooth. Two device generations are considered, one with 0.25 μm, the other with 0.1 μm gate length. The device geometries and source/drain doping profiles are kept fixed during optimization and supply voltages are chosen suitable for ultra-low-power purposes. In a first optimization study the drive current of NMOS transistors is maximized while keeping the leakage current below a limit of 1 pA/μm. This results in peaking channel doping devices (PCD) with narrow doping peaks placed asymmetrically in the channel. Drive current improvements of 45 % and 71 % for the 0.25 μm and 0.1 μm devices, respectively, are achieved compared to uniformly doped devices. The PCD device is studied in detail and explanations for

Development of an underground HPGe array facility for ultra low radioactivity measurements

Energy Technology Data Exchange (ETDEWEB)

Sala, E.; Kang, W. G.; Kim, Y. D.; Lee, M. H.; Leonard, D. S. [Center for Underground Physics - Institute for Basic Science, Daejeon (Korea, Republic of); Hahn, I. S.; Kim, G. W.; Park, S. Y. [Ewha Womans University, Physics Department, Seoul (Korea, Republic of)

2015-08-17

Low Level Counting techniques using low background facilities are continuously under development to increase the possible sensitivity needed for rare physics events experiments. The CUP (Center for Underground Physics) group of IBS is developing, in collaboration with Canberra, a ultra low background instrument composed of two arrays facing each other with 7 HPGe detectors each. The low radioactive background of each detector has been evaluated and improved by the material selection of the detector components. Samples of all the building materials have been provided by the manufacturer and the contaminations had been measured using an optimized low background 100% HPGe with a dedicated shielding. The evaluation of the intrinsic background has been performed using MonteCarlo simulations and considering the contribution of each material with the measured contamination. To further reduce the background, the instrument will be placed in the new underground laboratory at YangYang exploiting the 700m mountain coverage and radon-free air supplying system. The array has been designed to perform various Ultra Low background measurements; the sensitivity we are expecting will allow not only low level measurements of Ra and Th contaminations in Copper or other usually pure materials, but also the search for rare decays. In particular some possible candidates and configurations to detect the 0νECEC (for example {sup 106}Cd and {sup 156}Dy) and rare β decays ({sup 96}Zr, {sup 180m}Ta , etc ) are under study.

Development activities, challenges and prospects for the hydropower sector in Austria

Science.gov (United States)

Wagner, Beatrice; Hauer, Christoph; Habersack, Helmut

2017-04-01

This contribution intends to give an overview of hydropower development activities in Austria and deepen the knowledge on actual strategies and planning documents. Thereby, the focus is on a climate and energy policy based perspective, also analyzing economic trends at the hydropower sector due to energy market changes in the last years. This includes a comparison with other political strategies and programs dealing with hydropower exploitation based on selected countries. With respect to technology developments, a concise review on technological innovations, such as hydrokinetic energy conversion systems, and new constructive designs of conventional hydropower plants in Austria will be given. Moreover, potential impacts on environment and aquatic ecosystems are described. Finally, key challenges and prospects will be identified and discussed.

78 FR 58535 - Hydropower Regulatory Efficiency Act of 2013; Supplemental Notice of Workshop

Science.gov (United States)

2013-09-24

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. AD13-9-000] Hydropower... license for hydropower development at non-powered dams and closed-loop pumped storage projects in compliance with section 6 of the Hydropower Regulatory Efficiency Act of 2013. The workshop will be held in...

The Grossmatt hydro-power station

International Nuclear Information System (INIS)

Hintermann, M.

2006-01-01

This final report for the Swiss Federal Office of Energy (SFOE) presents the project for a small hydropower station on the Birs river in north-western Switzerland. The report reviews the history of the project, in which a new 385 kW-hydro-power station at the site of an earlier installation is foreseen. Details are presented on the investigations made and on the co-ordination with the owners of the hydro-power station situated up-river, the local power utility and the local authorities. Also, the requirements placed on the project by the fishing authorities are quoted and the solution foreseen is described. Also discussed are the requirements placed on the project by legislation on environmental impact and flood protection. Figures on electrical energy production and building costs are presented

Dielectric response of KCN crystals at ultra-low frequencies

OpenAIRE

Ziemath, Ervino C.; Aegerter, Michel A.; Slaets, J.

1987-01-01

We describe an ultra low frequency equipment employing programmable digital technique. The system is used to measure the dielectric parameters et, en and tg d or pure KCN crystals as a function of temperature in the frequency range 10-2 Hz to 40 Hz. The relaxation time of the Cn dipoles presents a classical temperature activated reorientation behaviour characterized by an Arrhenius law t=to exp (U/kT) with t0=7,26 x 10-15 s and U = 0,147 eV.

Operating multireservoir hydropower systems for downstream water quality

International Nuclear Information System (INIS)

Hayes, D.F.

1990-01-01

Hydropower reservoir operations often impact tailwater quality and water quality in the stream or river below the impoundment for many miles. Determining optimal operating strategies for a system of hydropower reservoirs involves solving a highly dimensional nonlinear, nonconvex optimization problem. This research adds the additional complexities of downstream water quality considerations within the optimization formulation to determine operating strategies for a system of hydropower reservoirs operating in series (tandem) or parallel. The formulation was used to determine operating strategies for six reservoirs of the upper Cumberland river basin in Tennessee and Kentucky. Significant dissolved oxygen (DO) violations occur just upstream of Nashville, Tennessee below Old Hickory dam during the months of August and September. Daily reservoir releases were determined for the period of June through September which would produce the maximum hydropower revenue while meeting downstream water quality objectives. Optimal releases for three operational strategies were compared to historical operations for the years 1985, 1986, and 1988. These strategies included: spilling as necessary to meet water quality criteria, near normal operation (minimal spills), and drawdown of reservoirs as necessary to meet criteria without spills. Optimization results showed an 8% to 15% hydropower loss may be necessary to meet water quality criteria through spills and a 2% to 9% improvement in DO below Old Hickory may be possible without significant spills. Results also showed that substantial increases in initial headwater elevations would be necessary to meet daily DO criteria and avoid spills. The optimal control theory algorithm used to solve the problem proved to be an efficient and robust solver of this large optimization problem

The blue water footprint of electricity from hydropower

Directory of Open Access Journals (Sweden)

M. M. Mekonnen

2012-01-01

Full Text Available Hydropower accounts for about 16% of the world's electricity supply. It has been debated whether hydroelectric generation is merely an in-stream water user or whether it also consumes water. In this paper we provide scientific support for the argument that hydroelectric generation is in most cases a significant water consumer. The study assesses the blue water footprint of hydroelectricity – the water evaporated from manmade reservoirs to produce electric energy – for 35 selected sites. The aggregated blue water footprint of the selected hydropower plants is 90 Gm³ yr⁻¹, which is equivalent to 10% of the blue water footprint of global crop production in the year 2000. The total blue water footprint of hydroelectric generation in the world must be considerably larger if one considers the fact that this study covers only 8% of the global installed hydroelectric capacity. Hydroelectric generation is thus a significant water consumer. The average water footprint of the selected hydropower plants is 68 m³ GJ⁻¹. Great differences in water footprint among hydropower plants exist, due to differences in climate in the places where the plants are situated, but more importantly as a result of large differences in the area flooded per unit of installed hydroelectric capacity. We recommend that water footprint assessment is added as a component in evaluations of newly proposed hydropower plants as well as in the evaluation of existing hydroelectric dams, so that the consequences of the water footprint of hydroelectric generation on downstream environmental flows and other water users can be evaluated.

Hydropower developments in Canada: number, size and jurisdictional and ecological distribution

Energy Technology Data Exchange (ETDEWEB)

Lee, Peter G.; Hanneman, Matt; Cheng, Ryan [Global Forest Watch Canada (Canada)

2011-08-15

For over 200 years, energy production and consumption, along with all human activities, have been contributing to global warming. This report is part of a project that examines 10 major energy sectors to provide information on Canada's energy options in the face of climate change; this present study gives information on hydropower reservoirs and associated dams in Canada. The mapping, jurisdictional and ecological distribution of reservoirs and dams across Canada is provided herein. Canada's hydropower installations are composed of 271 large hydropower facilities covering 58,015 km2 with a capacity of 71,857 MW, accounting for 44% of Canada's total technical hydroelectric capacity. Quebec, Ontario and British Columbia are the provinces with the most large hydropower dams; 19% of the watersheds are occupied in part by hydropower reservoirs and the taiga shield, boreal shield and montane cordillera ecozones contain most of the reservoir areas. The majority of future developments are expected to be built within 5km of intact forest landscapes.

Greenhouse gas emissions from hydropower. The state of research in 1996

International Nuclear Information System (INIS)

Gagnon, L.; Vate, J.F. van de

1997-01-01

This paper reports on the findings of a recent IAEA expert meeting on the assessment of greenhouse gas (GHG) emissions from the full 'lifecycle' of hydropower. It discusses the different categories of hydropower plants in view of the two main sources of GHG emissions: first, direct and indirect emissions associated with the construction of the plants; second, emissions from decaying biomass from land flooded by hydro reservoirs. In terms of GHG emissions, this paper shows that, in most cases, hydropower is a good alternative to fossil fuelled power generation. For hydropower plants in cold climate, a typical GHG emission factor is 15 g CO 2 equivalent/kWh, which is 30-60 times less than the factors of usual fossil fuel generation. For some hydropower plants in tropical climates, theoretical calculations have shown that reservoir emissions could be very high. However, no measurements of emission were taken from tropical reservoirs and the current level of research does not allow for a reliable evaluation. Research is urgently needed in humid tropical climates. (author)

The sustainability of hydropower projects in Brazil

Energy Technology Data Exchange (ETDEWEB)

de Methodio Maranhao Neto, Gil; Yana, Laurent

2010-09-15

The construction of hydropower plants unquestionably impacts the environment and communities. But countries such as Brazil have been able to build up a sophisticated socio-environmental legislation and institutions as well as a democratic and participative licensing process to protect the nature and the population affected. In some cases, plants greatly contribute towards the creation of local welfare to the population as well as good environmental practices. As a good example of best practices on socio-environmental standards, we will analyze Jirau Hydropower Project, currently under construction on the Madeira River, north of Brazil.

Computer applications in water conservancy and hydropower engineering

Energy Technology Data Exchange (ETDEWEB)

Chen, J

1984-09-20

The use of computers in China's water conservancy and hydropower construction began in the 1960s for exploration surveys, planning, design, construction, operation, and scientific research. Despite the positive results, and the formation of a 1000-person computer computation contingent, computer development among different professions is not balanced. The weaknesses and disparities in computer applications include an overall low level of application relative to the rest of the world, which is partly due to inadequate hardware and programs. The report suggests five ways to improve applications and popularize microcomputers which emphasize leadership and planning.

Ultra high resolution imaging of the human head at 8 tesla: 2K x 2K for Y2K.

Science.gov (United States)

Robitaille, P M; Abduljalil, A M; Kangarlu, A

2000-01-01

To acquire ultra high resolution MRI images of the human brain at 8 Tesla within a clinically acceptable time frame. Gradient echo images were acquired from the human head of normal subjects using a transverse electromagnetic resonator operating in quadrature and tuned to 340 MHz. In each study, a group of six images was obtained containing a total of 208 MB of unprocessed information. Typical acquisition parameters were as follows: matrix = 2,000 x 2,000, field of view = 20 cm, slice thickness = 2 mm, number of excitations (NEX) = 1, flip angle = 45 degrees, TR = 750 ms, TE = 17 ms, receiver bandwidth = 69.4 kHz. This resulted in a total scan time of 23 minutes, an in-plane resolution of 100 microm, and a pixel volume of 0.02 mm3. The ultra high resolution images acquired in this study represent more than a 50-fold increase in in-plane resolution relative to conventional 256 x 256 images obtained with a 20 cm field of view and a 5 mm slice thickness. Nonetheless, the ultra high resolution images could be acquired both with adequate image quality and signal to noise. They revealed numerous small venous structures throughout the image plane and provided reasonable delineation between gray and white matter. The elevated signal-to-noise ratio observed in ultra high field magnetic resonance imaging can be utilized to acquire images with a level of resolution approaching the histological level under in vivo conditions. However, brain motion is likely to degrade the useful resolution. This situation may be remedied in part with cardiac gating. Nonetheless, these images represent a significant advance in our ability to examine small anatomical features with noninvasive imaging methods.

Using MOF-74 for Hg2+ removal from ultra-low concentration aqueous solution

International Nuclear Information System (INIS)

Xiong, Yang Yang; Li, Jian Qiang; Gong, Le Le; Feng, Xue Feng; Meng, Li Na; Zhang, Le; Meng, Pan Pan; Luo, Ming Biao; Luo, Feng

2017-01-01

Mercury (Hg 2+ ) ions have very high toxicity and widely spread as environmental pollutants. At present, many efforts have been taken to remove the hazardous materials of mercury(II) by adsorption, and it is highly desirable to develop a novel adsorbent with high adsorptive capacities. However it is still a big challenge to remove the ultra-low-concentration mercury ions from water. In this paper, MOF-74-Zn is explored for such function, showing high removal rate of Hg(II) from water without any pretreatment, especially for the ultra-trace Hg(II) ions in the ppb magnitude with the removal rate reaching to 54.48%, 69.71%, 72.26% when the initial concentration of Hg(II) is 20ppb, 40ppb, 50ppb, respectively. - Graphical abstract: The absorption of mercury ions on MOF-74-Zn is due to somewhat weak interactions between MOF skeleton that is composed of carboxylate and hydroxy group and Hg2+ ions. - Highlights: • MOF-74-Zn shows high removal rate of Hg(II) from water without any pretreatment. • The MOF-74-Zn has a notable performance at ultra-low concentration of Hg(II). • MOF-74-Zn shows the potential for Hg(II) removal from industrial waste water.

Hydropower development and the meaning of place. Multi-ethnic hydropower struggles in Sikkim, India

NARCIS (Netherlands)

Dukpa, Rinchu Doma; Joshi, Deepa; Boelens, Rutgerd

2018-01-01

Academic research and media tend to emphasize the strong opposition to hydropower development in Sikkim, India, and position this as resistance to an environmentally-destructive, trans-local development, particularly by the culturally-rooted, ethnic minority Bhutia and Lepcha communities. There are

Very Low Head Turbine Deployment in Canada

International Nuclear Information System (INIS)

Kemp, P; Williams, C; Sasseville, Remi; Anderson, N

2014-01-01

The Very Low Head (VLH) turbine is a recent turbine technology developed in Europe for low head sites in the 1.4 - 4.2 m range. The VLH turbine is primarily targeted for installation at existing hydraulic structures to provide a low impact, low cost, yet highly efficient solution. Over 35 VLH turbines have been successfully installed in Europe and the first VLH deployment for North America is underway at Wasdell Falls in Ontario, Canada. Deployment opportunities abound in Canada with an estimated 80,000 existing structures within North America for possible low-head hydro development. There are several new considerations and challenges for the deployment of the VLH turbine technology in Canada in adapting to the hydraulic, environmental, electrical and social requirements. Several studies were completed to determine suitable approaches and design modifications to mitigate risk and confirm turbine performance. Diverse types of existing weirs and spillways pose certain hydraulic design challenges. Physical and numerical modelling of the VLH deployment alternatives provided for performance optimization. For this application, studies characterizing the influence of upstream obstacles using water tunnel model testing as well as full-scale prototype flow dynamics testing were completed. A Cold Climate Adaptation Package (CCA) was developed to allow year-round turbine operation in ice covered rivers. The CCA package facilitates turbine extraction and accommodates ice forces, frazil ice, ad-freezing and cold temperatures that are not present at the European sites. The Permanent Magnet Generator (PMG) presents some unique challenges in meeting Canadian utility interconnection requirements. Specific attention to the frequency driver control and protection requirements resulted in a driver design with greater over-voltage capability for the PMG as well as other key attributes. Environmental studies in Europe included fish friendliness testing comprised of multiple in

Very Low Head Turbine Deployment in Canada

Science.gov (United States)

Kemp, P.; Williams, C.; Sasseville, Remi; Anderson, N.

2014-03-01

The Very Low Head (VLH) turbine is a recent turbine technology developed in Europe for low head sites in the 1.4 - 4.2 m range. The VLH turbine is primarily targeted for installation at existing hydraulic structures to provide a low impact, low cost, yet highly efficient solution. Over 35 VLH turbines have been successfully installed in Europe and the first VLH deployment for North America is underway at Wasdell Falls in Ontario, Canada. Deployment opportunities abound in Canada with an estimated 80,000 existing structures within North America for possible low-head hydro development. There are several new considerations and challenges for the deployment of the VLH turbine technology in Canada in adapting to the hydraulic, environmental, electrical and social requirements. Several studies were completed to determine suitable approaches and design modifications to mitigate risk and confirm turbine performance. Diverse types of existing weirs and spillways pose certain hydraulic design challenges. Physical and numerical modelling of the VLH deployment alternatives provided for performance optimization. For this application, studies characterizing the influence of upstream obstacles using water tunnel model testing as well as full-scale prototype flow dynamics testing were completed. A Cold Climate Adaptation Package (CCA) was developed to allow year-round turbine operation in ice covered rivers. The CCA package facilitates turbine extraction and accommodates ice forces, frazil ice, ad-freezing and cold temperatures that are not present at the European sites. The Permanent Magnet Generator (PMG) presents some unique challenges in meeting Canadian utility interconnection requirements. Specific attention to the frequency driver control and protection requirements resulted in a driver design with greater over-voltage capability for the PMG as well as other key attributes. Environmental studies in Europe included fish friendliness testing comprised of multiple in

An Ultra-Low-Latency Geo-Routing Scheme for Team-Based Unmanned Vehicular Applications

KAUST Repository

Bader, Ahmed; Alouini, Mohamed-Slim

2016-01-01

Results and lessons learned from the implementation of a novel ultra low-latency geo-routing scheme are presented in this paper. The geo-routing scheme is intended for team-based mobile systems whereby a cluster of unmanned autonomous vehicles

Disappearing rivers — The limits of environmental assessment for hydropower in India

International Nuclear Information System (INIS)

Erlewein, Alexander

2013-01-01

The mountain rivers of the Indian Himalaya possess a vast potential for hydropower generation. After decades of comparatively modest development recent years have seen a major intensification in the construction of new hydropower dams. Although increasingly portrayed as a form of renewable energy generation, hydropower development may lead to extensive alterations of fluvial systems and conflicts with resource use patterns of local communities. To appraise and reduce adverse effects is the purpose of statutory Environmental Impact Assessments (EIA) and corresponding mitigation plans. However, in the light of ambitious policies for hydropower expansion conventional approaches of environmental assessment are increasingly challenged to keep up with the intensity and pace of development. This paper aims to explore the systemic limitations of environmental assessment for hydropower development in the Indian state of Himachal Pradesh. Based on a qualitative methodology involving interviews with environmental experts, document reviews and field observations the study suggests that the current practice of constraining EIAs to the project level fails to address the larger effects of extensive hydropower development. Furthermore, it is critically discussed as to what extent the concept of Strategic Environmental Assessment (SEA) might have the potential to overcome existing shortcomings

High-resolution assessment of global technical and economic hydropower potential

NARCIS (Netherlands)

Gernaat, David E.H.J.; Bogaart, Patrick W.; Vuuren, van Detlef P.; Biemans, Hester; Niessink, Robin

2017-01-01

Hydropower is the most important renewable energy source to date, providing over 72% of all renewable electricity globally. Yet, only limited information is available on the global potential supply of hydropower and the associated costs. Here we provide a high-resolution assessment of the technical

77 FR 2286 - Northern Illinois Hydropower, LLC; Notice of Meeting

Science.gov (United States)

2012-01-17

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Project No. 12717-002] Northern Illinois Hydropower, LLC; Notice of Meeting a. Date and Time of Meeting: Thursday, January 26, 2012 from 11... Meeting: Commission staff will meet with Northern Illinois Hydropower, LLC to discuss potentially moving...

Study of multi-layered graphene by ultra-low energy SEM/STEM

Czech Academy of Sciences Publication Activity Database

Mikmeková, Eliška; Frank, Luděk; Müllerová, Ilona; Li, B. W.; Ruoff, R. S.; Lejeune, M.

2016-01-01

Roč. 63, March 2016 (2016), s. 136-142 ISSN 0925-9635 R&D Projects: GA TA ČR(CZ) TE01020118; GA MŠk(CZ) LO1212 EU Projects: European Commission(XE) 606988 - SIMDALEE2 Institutional support: RVO:68081731 Keywords : scanning ultra low energy electron microscopy * graphene * contamination * CVD Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering Impact factor: 2.561, year: 2016

The future of hydropower planning modeling

Science.gov (United States)

Haas, J.; Zuñiga, D.; Nowak, W.; Olivares, M. A.; Castelletti, A.; Thilmant, A.

2017-12-01

Planning the investment and operation of hydropower plants with optimization tools dates back to the 1970s. The focus used to be solely on the provision of energy. However, advances in computational capacity and solving algorithms, dynamic markets, expansion of renewable sources, and a better understanding of hydropower environmental impacts have recently led to the development of novel planning approaches. In this work, we provide a review, systematization, and trend analysis of these approaches. Further, through interviews with experts, we outline the future of hydropower planning modeling and identify the gaps towards it. We classified the found models along environmental, economic, multipurpose and technical criteria. Environmental interactions include hydropeaking mitigation, water quality protection and limiting greenhouse gas emissions from reservoirs. Economic and regulatory criteria consider uncertainties of fossil fuel prices and relicensing of water rights and power purchase agreements. Multipurpose considerations account for irrigation, tourism, flood protection and drinking water. Recently included technical details account for sedimentation in reservoirs and variable efficiencies of turbines. Additional operational considerations relate to hydrological aspects such as dynamic reservoir inflows, water losses, and climate change. Although many of the above criteria have been addressed in detail on a project-to-project basis, models remain overly simplistic for planning large power fleets. Future hydropower planning tools are expected to improve the representation of the water-energy nexus, including environmental and multipurpose criteria. Further, they will concentrate on identifying new sources of operational flexibility (e.g. through installing additional turbines and pumps) for integrating renewable energy. The operational detail will increase, potentially emphasizing variable efficiencies, storage capacity losses due to sedimentation, and the

Hydrogen production from small hyropower sites. Final report

Energy Technology Data Exchange (ETDEWEB)

1980-04-01

A synergistic relationship was not found to exist between low-head hydropower and electrolytic hydrogen production. The storageability of hydrogen was expected to mitigate problems of hydrogen generation variability associated with the use of low-head hydropower as the power source. The expense of gaseous hydrogen storage equipment effectively eliminates storage as a means to decouple hydrogen demand and power/hydrogen production. From the opposite perspective, the availability of a low and stable cost of power from low-head hydro was expected to improve the competitiveness of electrolysis. In actuality, the results indicated that hydroelectric power from small dams would be comparatively expensive by current grid power standards (mid-1979). Electrolysis, in the capacity range considered here, is less sensitive to the cost of the power than originally presumed. Other costs including depreciation and capital related charges are more significant. Due to power generation variability, sole reliance on low-head hydropower to provide electricity to the cells would reduce the utilization of the hydrogen production investment, resulting in an increase in unit production costs. These factors were paramount in the Air Products recommendation to discontinue the study before continuing to more detailed stages of analysis, including an analysis of a site specific facility and the construction of a demonstration facility. Another major factor was the unavailability of a pipeline hydrogen supply situation which, because of lower distribution and capital costs, could have been commercially viable. An unfavorable judgment on the combined facility should not be misinterpreted and extended to the component systems. Although a detailed analysis of the individual prospects for electrolysis and low-head hydropower was beyond the study scope, the reader will realize, as the study is reviewed, that each is worthy of individual consideration.

Impact of low-head hydropower generation at Morgan Falls, LaHave River on migrating Atlantic salmon (Salmo salar)

International Nuclear Information System (INIS)

Amiro, P.G.; Jansen, H.

2000-01-01

A study was conducted to assess the impact that a low-head hydro electric power generating facility has on Atlantic salmon populations, particularly salmon smolts migrating downstream. The facility, located at Morgan Falls, LaHave River in Nova Scotia, is adjacent to a fishway and counting trap used to monitor salmon migration. Since 1972, the effects monitoring at the power facility for Atlantic salmon smolts concentrated on estimating three rates: (1) the facility use rate for downstream migrating smolts, (2) the louver efficiency rate for smolts entering the power canal, and (3) the turbine mortality rate for smolts passing through the turbine. Estimates of the number of wild smolt produced above the falls were determined and together with adult salmon data collected at the fishway, the potential impact of the facility on the salmon population was assessed. In this study, a total of 4,750 tagged smolts were released on four dates in 1997. Counts were recorded as the fish exited the bypass collection tank during louver or turbine testing periods and during daytime and evening hours. The estimated louver efficiencies of 86.3 and 88.3 per cent were higher than previously reported near-surface efficiencies of 80 per cent guidance for Atlantic salmon smolts experiencing a bypass acceleration factor of 1.26:1. Louver efficiencies of 96 per cent were estimated if fish that were recovered in the bypass holding tank after the experiments were included. Estimates of turbine mortality ranged from 15.4 per cent to 78.5 per cent, depending on the assumption about the missing fish. Mortalities in the assessment facility were due to turbulence in the bypass holding tank and impingement of fish on the incline screen fish separator. 7 refs., 10 tabs., 6 figs

Ultra-dense hot low Z line transition opacity simulations

International Nuclear Information System (INIS)

Sauvan, P.; Minguez, E.; Gil, J.M.; Rodriguez, R.; Rubiano, J.G.; Martel, P.; Angelo, P.; Schott, R.; Philippe, F.; Leboucher-Dalimier, E.; Mancini, R.; Calisti, A.

2002-01-01

In this work two atomic physics models (the IDEFIX code using the dicenter model and the code based on parametric potentials ANALOP) have been used to calculate the opacities for bound-bound transitions in hot ultra-dense, low Z plasmas. These simulations are in connection with experiments carried out at LULI during the last two years, focused on bound-bound radiation. In this paper H-like opacities for aluminum and fluorine plasmas have been simulated, using both theoretical models, in a wide range of densities and temperatures higher than 200 eV

Experiments on Quantum Hall Topological Phases in Ultra Low Temperatures

International Nuclear Information System (INIS)

Du, Rui-Rui

2015-01-01

This project is to cool electrons in semiconductors to extremely low temperatures and to study new states of matter formed by low-dimensional electrons (or holes). At such low temperatures (and with an intense magnetic field), electronic behavior differs completely from ordinary ones observed at room temperatures or regular low temperature. Studies of electrons at such low temperatures would open the door for fundamental discoveries in condensed matter physics. Present studies have been focused on topological phases in the fractional quantum Hall effect in GaAs/AlGaAs semiconductor heterostructures, and the newly discovered (by this group) quantum spin Hall effect in InAs/GaSb materials. This project consists of the following components: 1) Development of efficient sample cooling techniques and electron thermometry: Our goal is to reach 1 mK electron temperature and reasonable determination of electron temperature; 2) Experiments at ultra-low temperatures: Our goal is to understand the energy scale of competing quantum phases, by measuring the temperature-dependence of transport features. Focus will be placed on such issues as the energy gap of the 5/2 state, and those of 12/5 (and possible 13/5); resistive signature of instability near 1/2 at ultra-low temperatures; 3) Measurement of the 5/2 gaps in the limit of small or large Zeeman energies: Our goal is to gain physics insight of 5/2 state at limiting experimental parameters, especially those properties concerning the spin polarization; 4) Experiments on tuning the electron-electron interaction in a screened quantum Hall system: Our goal is to gain understanding of the formation of paired fractional quantum Hall state as the interaction pseudo-potential is being modified by a nearby screening electron layer; 5) Experiments on the quantized helical edge states under a strong magnetic field and ultralow temperatures: our goal is to investigate both the bulk and edge states in a quantum spin Hall insulator under

Impact of Different Time Series Streamflow Data on Energy Generation of a Run-of-River Hydropower Plant

Science.gov (United States)

Kentel, E.; Cetinkaya, M. A.

2013-12-01

Global issues such as population increase, power supply crises, oil prices, social and environmental concerns have been forcing countries to search for alternative energy sources such as renewable energy to satisfy the sustainable development goals. Hydropower is the most common form of renewable energy in the world. Hydropower does not require any fuel, produces relatively less pollution and waste and it is a reliable energy source with relatively low operating cost. In order to estimate the average annual energy production of a hydropower plant, sufficient and dependable streamflow data is required. The goal of this study is to investigate impact of streamflow data on annual energy generation of Balkusan HEPP which is a small run-of-river hydropower plant at Karaman, Turkey. Two different stream gaging stations are located in the vicinity of Balkusan HEPP and these two stations have different observation periods: one from 1986 to 2004 and the other from 2000 to 2009. These two observation periods show different climatic characteristics. Thus, annual energy estimations based on data from these two different stations differ considerably. Additionally, neither of these stations is located at the power plant axis, thus streamflow observations from these two stream gaging stations need to be transferred to the plant axis. This requirement introduces further errors into energy estimations. Impact of different streamflow data and transfer of streamflow observations to plant axis on annual energy generation of a small hydropower plant is investigated in this study.

Coherence between institutions and technologies - The case of mini hydropower in Switzerland

OpenAIRE

Crettenand, Nicolas

2009-01-01

Switzerland, with the forecasted electricity gap between domestic production and demand, aims to significantly increase renewable energy sources including hydropower. Mini hydropower (below 1MW) currently has considerable unused technical potential. As a renewable energy source (RES) it can contribute to climate change mitigation. CO2-taxes or emission trading systems (ETS) for planned thermal power plants could help facilitate mini hydropower (MHP). The technology is mature, but requires ade...

Design and Analysis of Double-Gate MOSFETs for Ultra-Low Power Radio Frequency Identification (RFID: Device and Circuit Co-Design

Directory of Open Access Journals (Sweden)

Tony T. Kim

2011-07-01

Full Text Available Recently, double-gate MOSFETs (DGMOSFETs have been shown to be more optimal for ultra-low power circuit design due to the improved subthreshold slope and the reduced leakage current compared to bulk CMOS. However, DGMOSFETs for subthreshold circuit design have not been much explored in comparison to those for strong inversion-based design. In this paper, various configurations of DGMOSFETs, such as tied/independent gates and symmetric/asymmetric gate oxide thickness are explored for ultra-low power and high efficient radio frequency identification (RFID design. Comparison of bulk CMOS with DGMOSFETs has been conducted in ultra-low power subthreshold digital logic design and rectifier design, emphasizing the scope of the nano-scale DGMOSFET technology for future ultra-low power systems. The DGMOSFET-based subthreshold logic improves energy efficiency by more than 40% compared to the bulk CMOS-based logic at 32 nm. Among the various DGMOSFET configurations for RFID rectifiers, symmetric tied-gate DGMOSFET has the best power conversion efficiency and the lowest power consumption.

Ultra-low-volume space sprays in mosquito control: a critical review.

Science.gov (United States)

Bonds, J A S

2012-06-01

The availability of tools to control mosquito (Diptera:Culicidae) vectors that transmit disease is often limited by a variety of economic, environmental and social issues. In emergency conditions (epidemics, hurricanes, floods etc.), the application of pesticides as space sprays (either by ground or air) is the common method of choice in order to rapidly limit adult local mosquito production in the affected area. Space spray application now employs ultra-low-volume technology for the control of adult mosquitoes. However, the use of space sprays often raises social and environmental concerns by the general public that is served. This review will define and illustrate modern ultra-low-volume technology for the purpose of application as a space spray, as well as describing the engineering controls that have been developed to minimize the environmental impact. The primary social concern is validity and efficacy of application. To address this point, the review will attempt to synthesize the global literature to address the effectiveness of space sprays to significantly impact mosquito vectors in relation to human disease. © 2012 The Author. Medical and Veterinary Entomology © 2012 The Royal Entomological Society.

Ultra-Low Power Sensor System for Disaster Event Detection in Metro Tunnel Systems

Directory of Open Access Journals (Sweden)

Jonah VINCKE

2017-05-01

Full Text Available In this extended paper, the concept for an ultra-low power wireless sensor network (WSN for underground tunnel systems is presented highlighting the chosen sensors. Its objectives are the detection of emergency events either from natural disasters, such as flooding or fire, or from terrorist attacks using explosives. Earlier works have demonstrated that the power consumption for the communication can be reduced such that the data acquisition (i.e. sensor sub-system becomes the most significant energy consumer. By using ultra-low power components for the smoke detector, a hydrostatic pressure sensor for water ingress detection and a passive acoustic emission sensor for explosion detection, all considered threats are covered while the energy consumption can be kept very low in relation to the data acquisition. In addition to 1 the sensor system is integrated into a sensor board. The total average power consumption for operating the sensor sub-system is measured to be 35.9 µW for lower and 7.8 µW for upper nodes.

Ultra-thin smart acoustic metasurface for low-frequency sound insulation

Science.gov (United States)

Zhang, Hao; Xiao, Yong; Wen, Jihong; Yu, Dianlong; Wen, Xisen

2016-04-01

Insulating low-frequency sound is a conventional challenge due to the high areal mass required by mass law. In this letter, we propose a smart acoustic metasurface consisting of an ultra-thin aluminum foil bonded with piezoelectric resonators. Numerical and experimental results show that the metasurface can break the conventional mass law of sound insulation by 30 dB in the low frequency regime (sound insulation performance is attributed to the infinite effective dynamic mass density produced by the smart resonators. It is also demonstrated that the excellent sound insulation property can be conveniently tuned by simply adjusting the external circuits instead of modifying the structure of the metasurface.

Evaluating the marginal utility principle for long-term hydropower scheduling

International Nuclear Information System (INIS)

Zhao, Tongtiegang; Zhao, Jianshi; Liu, Pan; Lei, Xiaohui

2015-01-01

Highlights: • Analysis of one-, two- and multi-period hydropower scheduling. • Derivation of marginal cost and marginal return of carry-over storage. • Evaluation of the marginal utility principle in a case study of the Three Gorges Reservoir. - Abstract: The conversion of the potential energy of dammed water into hydropower depends on both reservoir storage and release, which are the major difficulties in hydropower reservoir operation. This study evaluates the marginal utility principle, which determines the optimal carry-over storage between periods, for long-term hydropower scheduling. Increasing marginal cost and decreasing marginal return are two important characteristics that determine the marginal utility principle in water supply. However, the notion of decreasing marginal return is inapplicable in hydropower scheduling. Instead, the carry-over storage from one period has an increasing marginal contribution to the power generation in the next period. Although carry-over storage incurs an increasing marginal cost to the power generation in the current period, the marginal return is higher than the marginal cost. The marginal return from the carry-over storage further increases in the multi-period case. These findings suggest saving as much carry-over storage as possible, which is bounded by the operational constraints of storage capacity, environmental flow, and installed capacity in actual hydropower scheduling. The marginal utility principle is evaluated for a case study of the Three Gorges Reservoir, and the effects of the constraints are discussed. Results confirm the theoretical findings and show that the marginal return from carry-over storage is larger than the marginal cost. The operational constraints help determine the optimal carry-over storage.

An Ultra-low Frequency Modal Testing Suspension System for High Precision Air Pressure Control

Directory of Open Access Journals (Sweden)

Qiaoling YUAN

2014-05-01

Full Text Available As a resolution for air pressure control challenges in ultra-low frequency modal testing suspension systems, an incremental PID control algorithm with dead band is applied to achieve high-precision pressure control. We also develop a set of independent hardware and software systems for high-precision pressure control solutions. Taking control system versatility, scalability, reliability, and other aspects into considerations, a two-level communication employing Ethernet and CAN bus, is adopted to complete such tasks as data exchange between the IPC, the main board and the control board ,and the pressure control. Furthermore, we build a single set of ultra-low frequency modal testing suspension system and complete pressure control experiments, which achieve the desired results and thus confirm that the high-precision pressure control subsystem is reasonable and reliable.

Dynamic Modeling of Adjustable-Speed Pumped Storage Hydropower Plant: Preprint

Energy Technology Data Exchange (ETDEWEB)

Muljadi, E.; Singh, M.; Gevorgian, V.; Mohanpurkar, M.; Havsapian, R.; Koritarov, V.

2015-04-06

Hydropower is the largest producer of renewable energy in the U.S. More than 60% of the total renewable generation comes from hydropower. There is also approximately 22 GW of pumped storage hydropower (PSH). Conventional PSH uses a synchronous generator, and thus the rotational speed is constant at synchronous speed. This work details a hydrodynamic model and generator/power converter dynamic model. The optimization of the hydrodynamic model is executed by the hydro-turbine controller, and the electrical output real/reactive power is controlled by the power converter. All essential controllers to perform grid-interface functions and provide ancillary services are included in the model.

The future of hydropower in Europe: Interconnecting climate, markets and policies

International Nuclear Information System (INIS)

Gaudard, Ludovic; Romerio, Franco

2014-01-01

Highlights: • Connecting the knowledges from various domains, in particular economics, engineering, policy and hydrology. • Giving the keys to assess the linking between hydropower, climate and electricity market. • Making an overall analysis. - Abstract: Hydropower is very important for electricity supply security in the European inter-connexion as well as for the economy of regions (primarily peripheral) that possess water resources. Its future may however be jeopardized by several factors: climate change, the development of new renewable energy, the creation of super and micro-grids, and progress in power storage technology. Energy and climate policy, as well as electricity market design and dynamics play a pivotal role. This article carries out a comprehensive analysis of all these factors and discusses the future of hydropower. This discussion follows an overview of the present situation and of future drivers. The technical, environmental, economic and political aspects of the problem are analyzed with an interdisciplinary approach. The stakes as well as the uncertainties are highlighted. The conclusion is that hydropower has a promising future, particularly in light of emerging sustainable energy policy, but that the risks should not be overlooked. Academics will find a comprehensive interdisciplinary analysis of hydropower in this article, whereas public bodies, communities and hydropower companies can identify the strategic variables that should be taken into consideration in the decision making process. The end of water concessions or authorizations is also evoked

Sustainability Risk Evaluation for Large-Scale Hydropower Projects with Hybrid Uncertainty

Directory of Open Access Journals (Sweden)

Weiyao Tang

2018-01-01

Full Text Available As large-scale hydropower projects are influenced by many factors, risk evaluations are complex. This paper considers a hydropower project as a complex system from the perspective of sustainability risk, and divides it into three subsystems: the natural environment subsystem, the eco-environment subsystem and the socioeconomic subsystem. Risk-related factors and quantitative dimensions of each subsystem are comprehensively analyzed considering uncertainty of some quantitative dimensions solved by hybrid uncertainty methods, including fuzzy (e.g., the national health degree, the national happiness degree, the protection of cultural heritage, random (e.g., underground water levels, river width, and fuzzy random uncertainty (e.g., runoff volumes, precipitation. By calculating the sustainability risk-related degree in each of the risk-related factors, a sustainable risk-evaluation model is built. Based on the calculation results, the critical sustainability risk-related factors are identified and targeted to reduce the losses caused by sustainability risk factors of the hydropower project. A case study at the under-construction Baihetan hydropower station is presented to demonstrate the viability of the risk-evaluation model and to provide a reference for the sustainable risk evaluation of other large-scale hydropower projects.

Organizing Environmental Flow Frameworks to Meet Hydropower Mitigation Needs

Science.gov (United States)

McManamay, Ryan A.; Brewer, Shannon K.; Jager, Henriette I.; Troia, Matthew J.

2016-09-01

The global recognition of the importance of natural flow regimes to sustain the ecological integrity of river systems has led to increased societal pressure on the hydropower industry to change plant operations to improve downstream aquatic ecosystems. However, a complete reinstatement of natural flow regimes is often unrealistic when balancing water needs for ecosystems, energy production, and other human uses. Thus, stakeholders must identify a prioritized subset of flow prescriptions that meet ecological objectives in light of realistic constraints. Yet, isolating aspects of flow regimes to restore downstream of hydropower facilities is among the greatest challenges of environmental flow science due, in part, to the sheer volume of available environmental flow tools in conjunction with complex negotiation-based regulatory procedures. Herein, we propose an organizational framework that structures information and existing flow paradigms into a staged process that assists stakeholders in implementing environmental flows for hydropower facilities. The framework identifies areas where regulations fall short of the needed scientific process, and provide suggestions for stakeholders to ameliorate those situations through advanced preparation. We highlight the strengths of existing flow paradigms in their application to hydropower settings and suggest when and where tools are most applicable. Our suggested framework increases the effectiveness and efficiency of the e-flow implementation process by rapidly establishing a knowledge base and decreasing uncertainty so more time can be devoted to filling knowledge gaps. Lastly, the framework provides the structure for a coordinated research agenda to further the science of environmental flows related to hydropower environments.

Valuing trade-offs of river ecosystem services in large hydropower development in Tibet, China

Science.gov (United States)

Yu, B.; Xu, L.

2015-12-01

Hydropower development can be considered as a kind of trade-offs of ecosystem services generated by human activity for their economic and energy demand, because it can increase some river ecosystem services but decrease others. In this context, an ecosystem service trade-off framework in hydropower development was proposed in this paper. It aims to identify the ecological cost of river ecosystem and serve for the ecological compensation during hydropower development, for the hydropower services cannot completely replace the regulating services of river ecosystem. The valuing trade-offs framework was integrated by the influenced ecosystem services identification and ecosystem services valuation, through ecological monitoring and ecological economic methods, respectively. With a case study of Pondo hydropower project in Tibet, China, the valuing trade-offs of river ecosystem services in large hydropower development was illustrated. The typical ecological factors including water, sediment and soil were analyzed in this study to identify the altered river ecosystem services by Pondo hydropower project. Through the field monitoring and valuation, the results showed that the Lhasa River ecosystem services value could be changed annually by Pondo hydropower project with the increment of 5.7E+8CNY, and decrement of 5.1E+7CNY. The ecological compensation for river ecosystem should be focus on water and soil conservation, reservoir dredging and tributaries habitat protection.

DOE Hydropower Program biennial report 1990--1991 (with updated annotated bibliography)

Energy Technology Data Exchange (ETDEWEB)

Chappell, J.R.; Rinehart, B.N.; Sommers, G.L. (Idaho National Engineering Lab., Idaho Falls, ID (United States)); Sale, M.J. (Oak Ridge National Lab., TN (United States))

1991-07-01

This report summarizes the activities of the US Department of Energy's (DOE) Hydropower Program for fiscal years 1990 and 1991, and provides an annotated bibliography of research, engineering, operations, regulations, and costs of projects pertinent to hydropower development. The Hydropower Program is organized as follows: background (including Technology Development and Engineering Research and Development); Resource Assessment; National Energy Strategy; Technology Transfer; Environmental Research; and, the bibliography discusses reports written by both private and non-Federal Government sectors. Most reports are available from the National Technical Information Service. 5 figs., 2 tabs.

Harnessing the hydropower potential in Africa: What should be the place and role of Grand Inga hydropower project?

Energy Technology Data Exchange (ETDEWEB)

Fall, Latsoucabe

2010-09-15

Harnessing Africa's huge hydropower potential should be made a priority for the sustainable development of the Continent. Particularly, Grand Inga hydropower project in DRC, due to its gigantic size (40,000 MW) and favourable natural characteristics, could be 'Africa's flagship Project of the 21st Century' offering enormous comparative advantages and opportunities for the benefits of the entire African Continent. Nevertheless, to make it a feasible and palpable 'Model Project', capable of producing clean and affordable energy, the paper tries to respond to key questions on the several daunting challenges to address for its sustainable, cost-effective and timely development and operation.

Advanced Durable Flexible Ultra Low Outgassing Thermal Control Coatings for NASA Science Missions, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — This Phase I program proposes to synthesize novel nanoengineered ultra low out gassing elastomers and formulate high temperature capable flexible thermal control...

Portfolio optimisation for hydropower producers that balances riverine ecosystem protection and producer needs

Science.gov (United States)

Yin, X. A.; Yang, Z. F.; Liu, C. L.

2014-04-01

In deregulated electricity markets, hydropower portfolio design has become an essential task for producers. The previous research on hydropower portfolio optimisation focused mainly on the maximisation of profits but did not take into account riverine ecosystem protection. Although profit maximisation is the major objective for producers in deregulated markets, protection of riverine ecosystems must be incorporated into the process of hydropower portfolio optimisation, especially against a background of increasing attention to environmental protection and stronger opposition to hydropower generation. This research seeks mainly to remind hydropower producers of the requirement of river protection when they design portfolios and help shift portfolio optimisation from economically oriented to ecologically friendly. We establish a framework to determine the optimal portfolio for a hydropower reservoir, accounting for both economic benefits and ecological needs. In this framework, the degree of natural flow regime alteration is adopted as a constraint on hydropower generation to protect riverine ecosystems, and the maximisation of mean annual revenue is set as the optimisation objective. The electricity volumes assigned in different electricity submarkets are optimised by the noisy genetic algorithm. The proposed framework is applied to China's Wangkuai Reservoir to test its effectiveness. The results show that the new framework could help to design eco-friendly portfolios that can ensure a planned profit and reduce alteration of the natural flow regime.

Optimization of Mangala Hydropower Station, Pakistan, using Optimization Techniques

Directory of Open Access Journals (Sweden)

Zaman Muhammad

2017-01-01

Full Text Available Hydropower generation is one of the key element in the economy of a country. The present study focusses on the optimal electricity generation from the Mangla reservoir in Pakistan. A mathematical model has been developed for the Mangla hydropower station and particle swarm and genetic algorithm optimization techniques were applied at this model for optimal electricity generation. Results revealed that electricity production increases with the application of optimization techniques at the proposed mathematical model. Genetic Algorithm can produce maximum electricity than Particle swarm optimization but the time of execution of particle swarm optimization is much lesser than the Genetic algorithm. Mangla hydropower station can produce up to 59*109 kWh electricity by using the flows optimally than 47*108 kWh production from traditional methods.

Small hydropower in Southern Africa – an overview of five countries in the region

NARCIS (Netherlands)

Jonker Klunne, Wim

2013-01-01

This paper looks at the status of small hydropower in Lesotho, Mozambique, South Africa, Swaziland and Zimbabwe. For each country, an overview will be given of the electricity sector and the role of hydropower, the potential for small hydropower and the expected future of this technology. Small

78 FR 69080 - Houtama Hydropower LLC; Notice of Preliminary Permit Application Accepted for Filing and...

Science.gov (United States)

2013-11-18

... Hydropower LLC; Notice of Preliminary Permit Application Accepted for Filing and Soliciting Comments, Motions To Intervene, and Competing Applications On August 14, 2013, Houtama Hydropower LLC filed an.... Hampton, CEO, Houtama Hydropower [[Page 69081

Seventy kilovolt ultra-low dose CT of the paranasal sinus: first clinical results

International Nuclear Information System (INIS)

Bodelle, B.; Wichmann, J.L.; Klotz, N.; Lehnert, T.; Vogl, T.J.; Luboldt, W.; Schulz, B.

2015-01-01

Aim: To evaluate the diagnostic image quality and radiation dose of low-dose 70 kV computed tomography (CT) of the paranasal sinus in comparison to 100 and 120 kV CT. Materials and methods: CT of the paranasal sinus was performed in 127 patients divided into three groups using different tube voltages and currents (70 kV/75 mAs, ultra-low dose protocol, n = 44; 100 kV/40 mAs, standard low-dose protocol, n = 42; 120 kV/40 mAs, standard protocol, n = 41). CT dose index (CTDIvol), dose–length product (DLP), attenuation, image noise and signal-to-noise ratio (SNR) were compared between the groups using Wilcoxon–Mann–Whitney U-test. Subjective diagnostic image quality was compared by using a five-point scale (1 = non-diagnostic, 5 = excellent, read by two readers in consensus) and Cohen's weighted kappa analysis for interobserver agreement. Results: Radiation dose was significantly lower with 70 kV acquisition than 100 and 120 kV (DLP: 31 versus 52 versus 82 mGy·cm; CTDI 2.33 versus 3.95 versus 6.31 mGy, all p < 0.05). Mean SNR (70 kV: 0.37; 100 kV: 0.21; 120 kV: 0.13; p < 0.05) and organ attenuation increased significantly with lower voltages. All examinations showed diagnostic image quality. Subjective diagnostic image quality was higher with standard protocols than the 70 kV protocol (120 kV: 5.0; 100 kV: 4.5; 70 kV: 3.5, p < 0.05) without significant differences with substantial interobserver agreement (κ > 0.59). Conclusion: The ultra-low dose (70 kV) CT imaging of the paranasal sinus allowed for significant dose reduction by 61% and an increased attenuation of organ structures in comparison to standard acquisition while maintaining diagnostic image quality with a slight reduction in subjective image quality. -- Highlights: •Image quality and radiation dose of 70 kV ultra-low dose CT of the paranasal sinus. •70 kV ultra-low dose CT of the paranasal sinus allows for dose reduction by 61%. •70 kV CT of the

Ultra-low pollutant emission combustion method and apparatus

International Nuclear Information System (INIS)

Khinkis, M.J.

1992-01-01

This patent describes a method for ultra-low pollutant emission combustion of fossil fuel. It comprises: introducing into a primary combustion chamber a first fuel portion of about 1 percent to about 20 percent of a total fuel to be combusted; introducing primary combustion air into the primary combustion chamber; introducing a first portion of water into the primary combustion chamber, having a first water heat capacity equivalent to a primary combustion air heat capacity of one of a primary combustion air amount of about 10 percent to about 60 percent of the first stoichiometirc requirement for complete combustion of the first fuel portion and an excess primary combustion air amount of about 20 percent to about 150 percent of the first stoichiometric requirement for complete combustion of the first fuel portion; burning the first fuel portion with the primary combustion air in the primary combustion chamber at a temperature abut 2000 degrees F to about 2700 degrees F producing initial combustion products; passing the initial combustion products into a secondary combustion chamber; introducing into the secondary combustion chamber a second fuel portion of about 80 percent to about 99 percent of the total fuel to be combusted; introducing secondary combustion air into the secondary combustion chamber in an amount of about 105 percent to about 130 percent of a second stoichiometric requirement for complete combustion of the second fuel portion; introducing a second portion of water into the secondary combustion chamber; burning the second fuel portion and any remaining fuel in the initial combustion products; passing the final combustion products into a dilution chamber; introducing dilution air into the dilution chamber; discharging the ultra-low pollutant emission vitiated air form the dilution chamber

Ultra-low dispersion spectroscopy of stars and galaxies

International Nuclear Information System (INIS)

Bappu, M.K.V.; Parthasarathy, M.

1977-01-01

Application of ultra-low dispersion spectroscopy 10,000 A mm - 1 , is described to study the nuclei of elliptical galaxies, the quasi-stellar objects and for the discovery of faint OB stars, reddened stars and red stars. The instrument used is an f/2 slitless spectrograph with a three degree quartz prism at the Cassegrain focus of the 102-cm Ritchey-Chratien reflector at Kavalur. The spectra cover a field of 40 minutes of arc and the dispersion is 10,000 A mm - 1 . Ultra-low dispersion spectra (microspectra) were obtained for fifteen elliptical and three SO galaxies from the list of Ekers and Ekers (1973) who classified them as compact and extended sources from the observations of radio emission at 6 cms. From an analysis of micro-spectra and from direct photographs with graded exposure times, it is found that all compact radio galaxies in the Ekers list also have optically compact nuclei. Some of these elliptical galaxies with compact nuclei show enhancement of intensity in the blue violet region. From an examination of microspectra of forty-three of the known quasi-stellar objects of different redshifts it is found that the most striking characteristic of the spectra is their flat appearance. This characteristic flatness is also noticed in the microspectrum of the large redshift quasi-stellar objects like OH 471 and OQ 172 which do not have UV excess. Because of this characteristic difference in the appearance of the microspectra of the quasi-stellar objects and stellar objects, it is possible to detect new OSO's with this technique. An application of this technique to detect red stars in our galaxy and in the Large Magellanic cloud is discussed. (author)

A new framework for sustainable hydropower development project

Science.gov (United States)

Johan, Kartina; Turan, Faiz Mohd; Gani, Nur Syazwani Abdul

2018-03-01

This project studies on the establishment of a new framework for sustainable hydropower development. A hydropower development is listed as one of the prescribed activities under the Environmental Quality Order 1987. Thus, Environmental Impact Assessment (EIA) guidelines must be referred to comply with the Department of Environment (DoE) requirements. In order to execute EIA, an assessment tool that will be utilized in the final evaluation phase must be determined. The selected assessment tool that will be used is Systematic Sustainability Assessment(SSA) which is a new integrated tool to evaluate the sustainability performance. A pilot run is conducted in five different departments within the Energy Company to validate the efficiency of the SSA tool. The parameters to be evaluated are constructed aligned with the Sustainable Development Goals (SDG) to maintain the sustainability features. Consequently, the performance level of the sustainability with respect to People, Planet and Profit (3P’s) is able to be discovered during evaluation phase in the hydropower development for continuous improvement.

Bridging the Information Gap: Remote Sensing and Micro Hydropower Feasibility in Data-Scarce Regions

Science.gov (United States)

Muller, Marc Francois

Access to electricity remains an impediment to development in many parts of the world, particularly in rural areas with low population densities and prohibitive grid extension costs. In that context, community-scale run-of-river hydropower---micro-hydropower---is an attractive local power generation option, particularly in mountainous regions, where appropriate slope and runoff conditions occur. Despite their promise, micro hydropower programs have generally failed to have a significant impact on rural electrification in developing nations. In Nepal, despite very favorable conditions and approximately 50 years of experience, the technology supplies only 4% of the 10 million households that do not have access to the central electricity grid. These poor results point towards a major information gap between technical experts, who may lack the incentives or local knowledge needed to design appropriate systems for rural villages, and local users, who have excellent knowledge of the community but lack technical expertise to design and manage infrastructure. Both groups suffer from a limited basis for evidence-based decision making due to sparse environmental data available to support the technical components of infrastructure design. This dissertation draws on recent advances in remote sensing data, stochastic modeling techniques and open source platforms to bridge that information gap. Streamflow is a key environmental driver of hydropower production that is particularly challenging to model due to its stochastic nature and the complexity of the underlying natural processes. The first part of the dissertation addresses the general challenge of Predicting streamflow in Ungauged Basins (PUB). It first develops an algorithm to optimize the use of rain gauge observations to improve the accuracy of remote sensing precipitation measures. It then derives and validates a process-based model to estimate streamflow distribution in seasonally dry climates using the stochastic

High-flow, low-head pumps provide safe passage for Pacific salmon

International Nuclear Information System (INIS)

Anon

2004-01-01

The installation of 29 ultra-low head, high capacity submersible pump and auxiliary equipment at the Rocky Reach Dam in Washington State to allow juvenile salmon safe passage on their journey down the Columbia River to the Pacific Ocean is described. The reputed cost of the project is US$160 million; its purpose is to get juvenile salmon safely around the Rocky Reach Dam without interfering with the dam's original mission of generating electric power. The project is the most expensive fish bypass on any Columbia River dam. Getting the salmon safely around the dam is intended to reduce the impact of hydroelectric power projects on the basin's salmon stocks which are now estimated at less than 10 per cent of their historic size, despite major hatchery programs. The Columbia River has the second largest volume flow of any river in the United States, and millions of people depend on it for employment in water-related industries, and for transportation. The new horizontally installed propeller pump was developed by ITT Flygt; it utilizes planetary gear reduced to match the motor speed with the propeller rpm. Each 90 kW propeller pump has a flow rate of seven cubic meters per second at a head of 0.55 metres. The auxiliary equipment includes 10 racks of flap gates to prevent reverse flow, electric controls, remote supervision, testing, installation and maintenance facilities. It is anticipated that the new bypass will allow the Chelan County Public Utility Department, owners of the facility, to phase out all current spills, except for a 16 per cent spill for 40 days each spring for Sockeye salmon which tend to travel too deep to use the bypass. Prior to installation of this new facility, 60 to 70 per cent of average daily flow in the spring and summer had to be sacrificed to accommodate all species of salmon and steelhead, with corresponding losses of power generating capacity

Modelling and controlling hydropower plants

CERN Document Server

Munoz-Hernandez, German Ardul; Jones, Dewi Ieuan

2013-01-01

Hydroelectric power stations are a major source of electricity around the world; understanding their dynamics is crucial to achieving good performance.  Modelling and Controlling Hydropower Plants discusses practical and well-documented cases of modelling and controlling hydropower station modelling and control, focussing on a pumped storage scheme based in Dinorwig, North Wales.  Single-input-single-output and multiple-input-multiple-output models, which cover the linear and nonlinear characteristics of pump-storage hydroelectric power stations, are reviewed. The most important dynamic features are discussed, and the verification of these models by hardware in the loop simulation is described. To show how the performance of a pump-storage hydroelectric power station can be improved, classical and modern controllers are applied to simulated models of the Dinorwig power plant. These include PID, fuzzy approximation, feed-forward and model-based predictive control with linear and hybrid prediction models. Mod...

Hydropower strategy for the Philippines

International Nuclear Information System (INIS)

McCandless, D.H.

1995-01-01

The government-owned National Power Corporation (NPC) of the Philippines is in the early stages of a complete privatisation programme. The electric power sector is expected eventually to be structured around a company that will own the major transmission facilities and will serve as a broker of power and energy between generating companies and the existing distribution companies, Rural Electric Co-operations and other power users. NPC's non-transmission assets will probably be spun-off into various corporations including three generating companies, an engineering and services company and a company owning the Calivaya-Botocan-Kalayaan hydro complex. Plans for increased capacity include a real term increase in the hydropower contribution although it will decline as a percentage of the energy mix as coal and gas plants are developed. Details of the privatisation of specific hydropower projects in the Luzon, Visayas and Mindanao grids are described. (U.K.)

Chromatic dispersion effects in ultra-low coherence interferometry

Energy Technology Data Exchange (ETDEWEB)

Lychagov, V V; Ryabukho, V P [N.G.Chernyshevsky Saratov State University (Russian Federation)

2015-06-30

We consider the properties of an interference signal shift from zero-path-difference position in the presence of an uncompensated dispersive layer in one of the interferometer arms. It is experimentally shown that in using an ultra-low coherence light source, the formation of the interference signal is also determined by the group velocity dispersion, which results in a nonlinear dependence of the position of the interference signal on the geometrical thickness of the dispersive layer. The discrepancy in the dispersive layer and compensator refractive indices in the third decimal place is experimentally shown to lead to an interference signal shift that is an order of magnitude greater than the pulse width. (interferometry)

Channel coding study for ultra-low power wireless design of autonomous sensor works

NARCIS (Netherlands)

Zhang, P.; Huang, Li; Willems, F.M.J.

2011-01-01

Ultra-low power wireless design is highly demanded for building up autonomous wireless sensor networks (WSNs) for many application areas. To keep certain quality of service with limited power budget, channel coding techniques can be applied to maintain the robustness and reliability of WSNs. In this

Hydropower recovery in water supply systems: Models and case study

International Nuclear Information System (INIS)

Vilanova, Mateus Ricardo Nogueira; Balestieri, José Antônio Perrella

2014-01-01

Highlights: • We present hydropower recovery models for water supply systems. • Hydropower recovery potential in water supply systems is highly variable. • The case studied could make the supply systems self-sufficient in terms of energy. • Hydropower recovery can reduce GHGs emissions and generate carbon credits. - Abstract: The energy efficiency of water supply systems can be increased through the recovery of hydraulic energy implicit to the volumes of water transported in various stages of the supply process, which can be converted into electricity through hydroelectric recovery systems. Such a process allows the use of a clean energy source that is usually neglected in water supplies, reducing its dependence on energy from the local network and the system’s operation costs. This article evaluates the possibilities and benefits of the use of water supply facilities, structures and equipment for hydraulic energy recovery, addressing several applicable hydroelectric models. A real case study was developed in Brazil to illustrate the technical, economic and environmental aspects of hydropower recovery in water supply systems

Analysis of the cost for the refurbishment of small hydropower plants

International Nuclear Information System (INIS)

Ogayar, B.; Vidal, P.G.; Hernandez, J.C.

2009-01-01

In view of all the concerns associated with fossil fuels and energy demand it is appropriate to investigate the large number of abandoned small hydropower plants. In order to solve the difficulty implied, by a viability study on the refurbishment of a small hydropower plant, a series of simple equations has been developed based on the economic optimization of the different elements. These equations can also be used for completely new hydropower plants. The result of this study will allow us to obtain quite approximate costs for the refurbishment of old hydropower plants, or the construction of new ones. These data on costs will act as a reference to examine real possibilities of refurbishment through different tools of financial and economic analysis. Although the equations developed have used unitary prices referring to Spain, they will be applicable to other countries just changing those prices for those of the country, required. (author)

CMOS circuits for electromagnetic vibration transducers interfaces for ultra-low voltage energy harvesting

CERN Document Server

Maurath, Dominic

2015-01-01

Chip-integrated power management solutions are a must for ultra-low power systems. This enables not only the optimization of innovative sensor applications. It is also essential for integration and miniaturization of energy harvesting supply strategies of portable and autonomous monitoring systems. The book particularly addresses interfaces for energy harvesting, which are the key element to connect micro transducers to energy storage elements. Main features of the book are: - A comprehensive technology and application review, basics on transducer mechanics, fundamental circuit and control design, prototyping and testing, up to sensor system supply and applications. - Novel interfacing concepts - including active rectifiers, MPPT methods for efficient tracking of DC as well as AC sources, and a fully-integrated charge pump for efficient maximum AC power tracking at sub-100µW ultra-low power levels. The chips achieve one of widest presented operational voltage range in standard CMOS technology: 0.44V to over...

Hydropower reservoirs: cytotoxic and genotoxic assessment using the Allium cepa root model.

Science.gov (United States)

Rambo, Cassiano Lazarotto; Zanotelli, Patrícia; Dalegrave, Daniela; De Nez, Dinara; Szczepanik, Jozimar; Carazek, Fábio; Franscescon, Francini; Rosemberg, Denis Broock; Siebel, Anna Maria; Magro, Jacir Dal

2017-03-01

Hydropower offers a reliable source of electricity in several countries, and Brazil supplies its energy needs almost entirely through hydropower plants. Nevertheless, hydropower plants comprise large buildings and water reservoirs and dams, resulting in huge ecological disruptions. Here, we analyzed the impact of four hydropower reservoirs construction in metals and pesticides incidence and the cytotoxic and genotoxic potential of sediment elutriate of rivers from southern Brazil. Our analyses have evidenced the elevated incidence of different metals (lead, iron, cadmium, and chrome) and pesticides (methyl parathion, atrazine, and 2,4-dichlorophenoxyacetic acid). We showed that Allium cepa exposed to sediment elutriates did not change the seed germination rate and mitotic index. However, roots from Allium cepa exposed to reservoirs sediment elutriates showed increased occurrence of chromosomal aberrations and nuclear abnormalities. Therefore, the results obtained in our study indicate that sediment from reservoirs present elevated concentration of metals and pesticides and a significant genotoxic potential. Taken together, our data support that hydropower reservoirs represent an environmental scenario that could impact surrounding wildlife and population.

DOE Hydropower Program Annual Report for FY 2004

Energy Technology Data Exchange (ETDEWEB)

Sommers, Garold L. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Hunt, Richard T. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Cada, Glenn F. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Sale, Michael J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Dauble, Dennis D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Carlson, Thomas [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Ahlgrimm, James [U.S. Dept. of Energy, Washington, D.C. (United States); Acker, Tomas L. [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2005-02-01

This report describes the progress of the R&D conducted in FY 2004 the under four program areas at the time: (1) Advanced Hydropower Technology (Large Turbine Field Testing, Water Use Optimization, and Improved Mitigation Practices); (2) Supporting Research and Testing (Environmental Performance Testing Methods, Computational and Physical Modeling, Instrumentation and Controls, and Environmental Analysis); (3) Systems Integration and Technology Acceptance (Hydro/Wind Integration, National Hydropower Collaborative, and Integration and Communications); and (4) Supporting Engineering and Analysis (Valuation Methods and Assessments and Characterization of Innovative Technology).

Assessing residual hydropower potential of the La Plata Basin accounting for future user demands

Science.gov (United States)

Popescu, I.; Brandimarte, L.; Perera, M. S. U.; Peviani, M.

2012-08-01

La Plata Basin is shared by five countries (Argentina, Bolivia, Brazil, Paraguay and Uruguay), which have fast growing economies in South America. These countries need energy for their sustainable development; hence, hydropower can play a very important role as a renewable clean source of energy. This paper presents an analysis of the current hydropower production and electricity demand in La Plata Basin (LPB), and it analyses the maximum and residual hydropower potential of the basin for a horizon of 30 yr (i.e. year 2040). Current hydropower production is estimated based on historical available data, while future energy production is deduced from the available water in the catchment (estimated based on measured hydrographs of the past years), whereas electricity demand is assessed by correlating existing electricity demand with the estimated population growth and economic development. The maximum and residual hydropower potential of the basin were assessed for the mean annual flows of the present hydrological regime (1970-2000) and topographical characteristics of the area. Computations were performed using an integrated GIS environment called VAPIDRO-ASTE released by the Research on Energy System (Italy). The residual hydropower potential of the basin is computed considering first that the water supply needs for population, industry and agriculture are served, and then hydropower energy is produced. The calculated hydropower production is found to be approximately half of the estimated electricity demand, which shows that there is a need to look for other sources of energy in the future.

FY 2000 report on the results of the regional consortium R and D project - Regional consortium energy R and D. Third year report. Ultra-high density information storage component; 2000 nendo chiiki consortium kenkyu kaihatsu jigyo - chiiki consortium energy kenkyu kaihatsu. Chokomitsudo joho storage component (dai 3 nendo) seika hokokusho

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-03-01

For the purpose of industrially creating next generation HDD (hard disk drive), the development was proceeded with of ultra-high density and energy saving type next generation HDD system. The following four were conducted: 1) development of active type magnetic head arm for high speed writing/reading-out; 2) development of ultra-smooth low-noise medium using ultra-clean process; 3) establishment of component technology of high efficiency lubricating materials; 4) development of reproductive magnetic head using TMR device. TMR device is an ultra-high sensitivity magnetic detecting device composed of three layers of ferromagnetic material/insulator/ferromagnetic material. As to the development of regenerative magnetic head, studies were made of the reduction in resistance of TRM device, fabrication of submicron device and system integration. For the development of low resistance TMR device, thickness of Al layer, oxidation conditions and heat treatment conditions were studied in detail. The tunnel joining was obtained in which RA value and TMR ratio are 80 ohm(center dot){mu}m{sup 2} and 30%, respectively, in case of the thickness of Al layer of 6.6 (angstrom). (NEDO)

Exploring current and projected tradeoffs between hydropower profitability and reliability of supply in the Alps

Science.gov (United States)

Anghileri, D.; Castelletti, A.; Burlando, P.

2015-12-01

The recent spreading of renewable energy across Europe and the associated production variability and uncertainty are emerging challenges for hydropower system operation. Widely distributed and highly intermittent solar and wind power generation systems, along with feed-in-tariffs, at which they are remunerated, are threating the operation of traditional hydropower systems. For instance, in countries where the transition to a larger production by means of renewable power systems is a novel process, e.g. Switzerland, many hydropower companies are operating their reservoirs with low or no profits, claiming for a revision of the entire energy market system. This situation goes along with the problem of ensuring energy supply both nowadays and in the future, with changing energy demand and available water resources. In this work, we focus on a hydropower system in the Swiss Alps to explore how different operating policies can cope with both adequate energy supply and profitable operation under current and future climate and socio-economic conditions. We investigate the operation of the Mattmark reservoir in South-West Switzerland. Mattmark is a pumped reservoir of 98 106 m3 fed by a natural catchment of 37 km2 and contributing catchments, summing up to 51 km2, connected by several diversion channels. The hydrological regime, snow- and ice-melt dominated, has already experienced changes in the last decades due to glacier retreat and is expected to be strongly impacted by climate change in the future. We use Multi-Objective optimization techniques to explore current tradeoffs between profitability and secure supply. We then investigate how tradeoffs may evolve in time under different climate change projections and energy market scenarios. Results inform on the co-evolution of climate- and socio-economic induced variations, thus unveiling potential co-benefit situations to hydropower generation and providing insights to future energy market design.

Using MOF-74 for Hg{sup 2+} removal from ultra-low concentration aqueous solution

Energy Technology Data Exchange (ETDEWEB)

Xiong, Yang Yang; Li, Jian Qiang; Gong, Le Le; Feng, Xue Feng; Meng, Li Na; Zhang, Le; Meng, Pan Pan; Luo, Ming Biao; Luo, Feng, E-mail: ecitluofeng@163.com

2017-02-15

Mercury (Hg{sup 2+}) ions have very high toxicity and widely spread as environmental pollutants. At present, many efforts have been taken to remove the hazardous materials of mercury(II) by adsorption, and it is highly desirable to develop a novel adsorbent with high adsorptive capacities. However it is still a big challenge to remove the ultra-low-concentration mercury ions from water. In this paper, MOF-74-Zn is explored for such function, showing high removal rate of Hg(II) from water without any pretreatment, especially for the ultra-trace Hg(II) ions in the ppb magnitude with the removal rate reaching to 54.48%, 69.71%, 72.26% when the initial concentration of Hg(II) is 20ppb, 40ppb, 50ppb, respectively. - Graphical abstract: The absorption of mercury ions on MOF-74-Zn is due to somewhat weak interactions between MOF skeleton that is composed of carboxylate and hydroxy group and Hg2+ ions. - Highlights: • MOF-74-Zn shows high removal rate of Hg(II) from water without any pretreatment. • The MOF-74-Zn has a notable performance at ultra-low concentration of Hg(II). • MOF-74-Zn shows the potential for Hg(II) removal from industrial waste water.

Operational constraints and hydrologic variability limit hydropower in supporting wind integration

International Nuclear Information System (INIS)

Fernandez, Alisha R; Blumsack, Seth A; Reed, Patrick M

2013-01-01

Climate change mitigation will require rapid adoption of low-carbon energy resources. The integration of large-scale wind energy in the United States (US) will require controllable assets to balance the variability of wind energy production. Previous work has identified hydropower as an advantageous asset, due to its flexibility and low-carbon emissions production. While many dams currently provide energy and environmental services in the US and globally, we find that multi-use hydropower facilities would face significant policy conflicts if asked to store and release water to accommodate wind integration. Specifically, we develop a model simulating hydroelectric operational decisions when the electric facility is able to provide wind integration services through a mechanism that we term ‘flex reserves’. We use Kerr Dam in North Carolina as a case study, simulating operations under two alternative reservoir policies, one reflecting current policies and the other regulating flow levels to promote downstream ecosystem conservation. Even under perfect information and significant pricing incentives, Kerr Dam faces operational conflicts when providing any substantial levels of flex reserves while also maintaining releases consistent with other river management requirements. These operational conflicts are severely exacerbated during periods of drought. Increase of payments for flex reserves does not resolve these operational and policy conflicts. (letter)

Long-term scheduling of large cascade hydropower stations in Jinsha River, China

International Nuclear Information System (INIS)

Wang, Chao; Zhou, Jianzhong; Lu, Peng; Yuan, Liu

2015-01-01

Highlights: • Proposing a Gaussian group selection strategy to overcome premature convergence. • Multi-population ant are developed to enhance the search ability. • Proposing a circulatory solution correction to handle constraints. • Numerical and real hydropower system simulation are used to verify its performance. • Compensation analysis has been done to large hydropower stations in Jinsha River. - Abstract: The Jinsha River is the third longest river in the world. It consists of four large hydropower stations with total installed capacity 42,960 MW lying on the upper stretches of the Yangtze River, which is the longest river in the word. Due to the great potential of large cascade hydropower stations on power generation, long-term scheduling of large cascade hydropower stations (LSLCHS) plays an important role in electrical power system. As more and more concentrations focused on the optimal operation of large cascade hydropower stations, the LSLCHS has been taken into a multi-dimensional, non-convex and non-linear optimization problem due to its complicated hydraulic connection relationships and varieties of complex constraints with considering its power generation, shipping and ecological characteristics. In order to solve this problem, a multi-population ant colony optimization for continuous domain (MACO R ) is proposed in this paper. A Gaussian group selection strategy is applied to overcome premature convergence and ants with different characteristics are employed to enhance search ability, and circulatory solution correction strategy is presented to handle outflow, water level and output constraints. Furthermore, the efficiency and stability of MACO R are verified by its more desirable results in comparison to other latest works in numerical simulation, and it can be a viable alternative for solving those complicated optimal problems. With the applications in hydropower operation, LSLCHS can obtain more power generation benefit than other

Development of Sustainability Assessment Framework in Hydropower sector

Science.gov (United States)

Soliha Sahimi, Nur; Turan, Faiz Mohd; Johan, Kartina

2017-08-01

Nowadays, Malaysian demand in energy sector was drastically increase due to technological developments. Since, hydropower is one of potential renewable energy source in Malaysia. The largest electricity utility company, Tenaga Nasional Berhad was provide an electricity to more than seven million people via independent suppliers in peninsular Malaysia and Sabah by intended a potential sustainable hydropower system. In order to increasingly the power capacity from current use, 1882 MW to more than 3000 MW by years 2020. In this study, the environmental issues and also the penalty to the responsible company especially on Tenaga Nasional Berhad (TNB) towards their project or business are one of the problems. Other than that, every project or business has to prepare a sustainability statement or sustainability report as vital to Bursa Malaysia Securities Berhad under their listing requirements. Next, the sustainability performance on their project cannot be determined to achieve the key performance indicators (KPI) satisfaction from Government, stakeholder or any responsible agencies. This study presents an exhaustive review of these studies and suggests a direction for future developments. Sustainability Assessment framework or self-assessment is decidedly as a significant framework to assist towards sustainability reporting and to produce a Sustainability index for Hydropower sector using a mathematical model study. The results reveal that, the quantitative measurement from Sustainability Assessment framework to Systematic Sustainability Asssesment tool can be produce. In doing so, it is possible to improve the performance of the project especially in hydropower planner.

Regulatory Approaches for Adding Capacity to Existing Hydropower Facilities

Energy Technology Data Exchange (ETDEWEB)

Levine, Aaron L. [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Curtis, Taylor L. [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Kazerooni, Borna [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

2017-10-24

In 2015, hydroelectric generation accounted for more than 6 percent of total net electricity generation in the United States and 46 percent of electricity generation from all renewables. The United States has considerable hydroelectric potential beyond what is already being developed. Nearly 7 GW of this potential is found by adding capacity to existing hydropower facilities. To optimize the value of hydroelectric generation, the U.S. Department of Energy's Hydropower Vision Study highlights the importance of adding capacity to existing facilities. This report provides strategic approaches and considerations for Federal Energy Regulatory Commission licensed and exempt hydropower facilities seeking to increase generation capacity, which may include increases from efficiency upgrades. The regulatory approaches reviewed for this report include capacity and non-capacity amendments, adding capacity during relicensing, and adding capacity when converting a license to a 10-MW exemption.

Optimized Interface Diversity for Ultra-Reliable Low Latency Communication (URLLC)

DEFF Research Database (Denmark)

Nielsen, Jimmy Jessen; Liu, Rongkuan; Popovski, Petar

2017-01-01

An important ingredient of the future 5G systems will be Ultra-Reliable Low-Latency Communication (URLLC). A way to offer URLLC without intervention in the baseband/PHY layer design is to use interface diversity and integrate multiple communication interfaces, each interface based on a different...... technology. Our approach is to use rateless codes to seamlessly distribute coded payload and redundancy data across multiple available communication interfaces. We formulate an optimization problem to find the payload allocation weights that maximize the reliability at specific target latency values...

Environmental certification for small hydropower plants

International Nuclear Information System (INIS)

Truffer, B.; Meier, W.; Vollenweider, S.; Seiler, B.; Dettli, R.

2001-01-01

This report for the Swiss Federal Institute for Environmental Science and Technology describes product-differentiation options for small hydropower plant in Switzerland and proposes a form of differentiation based on ecological characteristics as a promising market strategy. The labels created in various countries to assure customers of the environmental compatibility of 'green' power production are looked at. In particular, the implications for small hydropower plant associated with the Swiss green power labelling procedure introduced by the Association for the Promotion of Environmentally Sound Electricity (VUE) are discussed. The report proposes a simplified procedure for these small power stations and presents a sample calculation for the overall costs of certification. The report is rounded off with four detailed case studies in which the necessary upgrades to the plant and associated costs are discussed in detail

Assessing residual hydropower potential of the La Plata Basin accounting for future user demands

Directory of Open Access Journals (Sweden)

I. Popescu

2012-08-01

Full Text Available La Plata Basin is shared by five countries (Argentina, Bolivia, Brazil, Paraguay and Uruguay, which have fast growing economies in South America. These countries need energy for their sustainable development; hence, hydropower can play a very important role as a renewable clean source of energy. This paper presents an analysis of the current hydropower production and electricity demand in La Plata Basin (LPB, and it analyses the maximum and residual hydropower potential of the basin for a horizon of 30 yr (i.e. year 2040. Current hydropower production is estimated based on historical available data, while future energy production is deduced from the available water in the catchment (estimated based on measured hydrographs of the past years, whereas electricity demand is assessed by correlating existing electricity demand with the estimated population growth and economic development. The maximum and residual hydropower potential of the basin were assessed for the mean annual flows of the present hydrological regime (1970–2000 and topographical characteristics of the area.

Computations were performed using an integrated GIS environment called VAPIDRO-ASTE released by the Research on Energy System (Italy. The residual hydropower potential of the basin is computed considering first that the water supply needs for population, industry and agriculture are served, and then hydropower energy is produced. The calculated hydropower production is found to be approximately half of the estimated electricity demand, which shows that there is a need to look for other sources of energy in the future.

Low-head hydro power

Science.gov (United States)

Lemer, E. J.

1980-11-01

With a view toward increasing the U.S. electric output, the Army Corps of Engineers has estimated that 55 GW can be obtained immediately from new capacity at existing dams and 40 GW more over the long term. Given the long lead times needed to build new dams, most interest has centered on the existing dams. The Corps of Engineers has established that 21 GW can be obtained from hydroelectric and 34 GW from nonpower dams. Existing hydroelectric sites are being expanded by the utilities, but exploitation of the nonpower dams will require governmental encouragement, because the vast majority are low-head sites (dams less than 40 m high). In the present paper, the question of economics and national policy is examined. The advantages which would accrue from substituting axial turbines for the Kaplan turbine are noted.

78 FR 61987 - Corbett Water District; Notice of Preliminary Determination of a Qualifying Conduit Hydropower...

Science.gov (United States)

2013-10-09

... District; Notice of Preliminary Determination of a Qualifying Conduit Hydropower Facility and Soliciting... construct a qualifying conduit hydropower facility, pursuant to section 30 of the Federal Power Act, as amended by section 4 of the Hydropower Regulatory Efficiency Act of 2013 (HREA). The Corbett Hydroelectric...

77 FR 58375 - Inglis Hydropower, LLC; Notice of Preliminary Permit Application Accepted for Filing and...

Science.gov (United States)

2012-09-20

... Hydropower, LLC; Notice of Preliminary Permit Application Accepted for Filing and Soliciting Comments, Motions To Intervene, and Competing Applications On May 18, 2012, Inglis Hydropower, LLC filed an... study the feasibility of a hydropower project located at the Inglis Bypass Channel, located on the...

75 FR 59706 - Coastal Hydropower, LLC; Notice of Preliminary Permit Application Accepted for Filing and...

Science.gov (United States)

2010-09-28

... Hydropower, LLC; Notice of Preliminary Permit Application Accepted for Filing and Soliciting Comments... on July 16, 2010, Coastal Hydropower, LLC filed an application for a preliminary permit, pursuant to... generation of the project would be 7.9 gigawatt-hours. Applicant Contact: Neil Anderson, Coastal Hydropower...

77 FR 31349 - Coastal Hydropower, LLC; Notice of Preliminary Permit Application Accepted for Filing and...

Science.gov (United States)

2012-05-25

... Hydropower, LLC; Notice of Preliminary Permit Application Accepted for Filing and Soliciting Comments, Motions To Intervene, and Competing Applications On April 12, 2012, Coastal Hydropower, LLC filed an... generation of 31.5 gigawatt-hours. Applicant Contact: Neil Anderson, Coastal Hydropower, LLC, Key Centre, 601...

Resource rent taxation and benchmarking-A new perspective for the Swiss hydropower sector

International Nuclear Information System (INIS)

Banfi, Silvia; Filippini, Massimo

2010-01-01

The electricity generation in Switzerland is mainly based on hydropower (55% of total production). The exploitation of water in the hydropower sector can generate significant so-called resource rents. These are defined by the surplus return above the value of capital, labor, materials, and energy used to exploit hydropower. In Switzerland, hydropower producers pay to the State a fixed fee per kW gross capacity. With this system the substantial differences in costs, revenues and in the production characteristics of the hydropower plants are not taken into account. In this context, the following paper has two main goals: (1) to discuss the introduction in the Swiss hydropower sector of a new payment system based on a resource rent tax; (2) To propose a combination of a RRT system with a benchmarking analysis of the production cost obtained through the estimation of a stochastic frontier variable cost function. We estimate a true random effects stochastic frontier variable cost function using panel data in order to overcome the asymmetric information problem. In addition, using the information on cost efficiency of the single companies, we show how to introduce in the RRT scheme a benchmark system which gives incentives to minimize the production costs.

Environmental sustainability assessment of hydropower plant in Europe using life cycle assessment

Science.gov (United States)

Mahmud, M. A. P.; Huda, N.; Farjana, S. H.; Lang, C.

2018-05-01

Hydropower is the oldest and most common type of renewable source of electricity available on this planet. The end of life process of hydropower plant have significant environmental impacts, which needs to be identified and minimized to ensure an environment friendly power generation. However, identifying the environmental impacts and health hazards are very little explored in the hydropower processing routes despite a significant quantity of production worldwide. This paper highlight the life-cycle environmental impact assessment of the reservoir based hydropower generation system located in alpine and non-alpine region of Europe, addressing their ecological effects by the ReCiPe and CML methods under several impact-assessment categories such as human health, ecosystems, global warming potential, acidification potential, etc. The Australasian life-cycle inventory database and SimaPro software are utilized to accumulate life-cycle inventory dataset and to evaluate the impacts. The results reveal that plants of alpine region offer superior environmental performance for couple of considered categories: global warming and photochemical oxidation, whilst in the other cases the outcomes are almost similar. Results obtained from this study will take part an important role in promoting sustainable generation of hydropower, and thus towards environment friendly energy production.

75 FR 59707 - Coastal Hydropower, LLC; Notice of Preliminary Permit Application Accepted for Filing and...

Science.gov (United States)

2010-09-28

... Hydropower, LLC; Notice of Preliminary Permit Application Accepted for Filing and Soliciting Comments... on July 16, 2010, Coastal Hydropower, LLC filed an application for a preliminary permit, pursuant to... Hydropower, LLC, Key Centre, 601 108th Avenue, NE., Suite 1900, Bellevue, WA 98004; phone: (425) 943-7690...

78 FR 64493 - Juneau Hydropower, Inc.; Notice of Subsequent Draft License Application (DLA) and Draft...

Science.gov (United States)

2013-10-29

... Hydropower, Inc.; Notice of Subsequent Draft License Application (DLA) and Draft Preliminary Draft... Hydropower, Inc. e. Name of Project: Sweetheart Lake Hydroelectric Project. f. Location: At the confluence of..., Business Manager, Juneau Hydropower, Inc., P.O. Box 22775, Juneau, AK 99802; 907-789-2775, email: duff...

75 FR 62516 - Northern Illinois Hydropower, LLC; Notice of Application Ready for Environmental Analysis and...

Science.gov (United States)

2010-10-12

... Illinois Hydropower, LLC; Notice of Application Ready for Environmental Analysis and Soliciting Comments...: Northern Illinois Hydropower, LLC. e. Name of Project: Dresden Island Project. f. Location: U.S. Army Corps... Zdunich, Northern Illinois Hydropower, LLC, 801 Oakland Avenue, Joliet, IL 60435, (312) 320-1610. i. FERC...

78 FR 63176 - Notice of Preliminary Determination of a Qualifying Conduit Hydropower Facility and Soliciting...

Science.gov (United States)

2013-10-23

... Preliminary Determination of a Qualifying Conduit Hydropower Facility and Soliciting Comments and Motions To... of intent to construct a qualifying conduit hydropower facility, pursuant to section 30 of the Federal Power Act, as amended by section 4 of the Hydropower Regulatory Efficiency Act of 2013 (HREA). The...

75 FR 62518 - Northern Illinois Hydropower, LLC; Notice of Application Ready for Environmental Analysis and...

Science.gov (United States)

2010-10-12

... Illinois Hydropower, LLC; Notice of Application Ready for Environmental Analysis and Soliciting Comments...: Northern Illinois Hydropower, LLC. e. Name of Project: Brandon Road Hydroelectric Project. f. Location: U.S... Hydropower, LLC, 801 Oakland Avenue, Joliet, IL 60435, (312) 320-1610. i. FERC Contact: Janet Hutzel, (202...

Rotatable Small Permanent Magnet Array for Ultra-Low Field Nuclear Magnetic Resonance Instrumentation: A Concept Study.

Science.gov (United States)

Vogel, Michael W; Giorni, Andrea; Vegh, Viktor; Pellicer-Guridi, Ruben; Reutens, David C

2016-01-01

We studied the feasibility of generating the variable magnetic fields required for ultra-low field nuclear magnetic resonance relaxometry with dynamically adjustable permanent magnets. Our motivation was to substitute traditional electromagnets by distributed permanent magnets, increasing system portability. The finite element method (COMSOL®) was employed for the numerical study of a small permanent magnet array to calculate achievable magnetic field strength, homogeneity, switching time and magnetic forces. A manually operated prototype was simulated and constructed to validate the numerical approach and to verify the generated magnetic field. A concentric small permanent magnet array can be used to generate strong sample pre-polarisation and variable measurement fields for ultra-low field relaxometry via simple prescribed magnet rotations. Using the array, it is possible to achieve a pre-polarisation field strength above 100 mT and variable measurement fields ranging from 20-50 μT with 200 ppm absolute field homogeneity within a field-of-view of 5 x 5 x 5 cubic centimetres. A dynamic small permanent magnet array can generate multiple highly homogeneous magnetic fields required in ultra-low field nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI) instruments. This design can significantly reduce the volume and energy requirements of traditional systems based on electromagnets, improving portability considerably.

Hydropower in Southeast United States, -a Hydroclimatological Perspective

Science.gov (United States)

Engstrom, J.

2016-12-01

Hydropower is unique among renewable energy sources for the ability to store its fuel (water) in reservoirs. The relationship between discharge, macro-scale drivers, and production is complex since production depends not only on water availability, but also upon decisions made by the institution owning the facility that has to consider many competing interests including economics, drinking water supply, recreational uses, etc. This analysis shows that the hydropower plants in Southeast U.S. (AL, GA, NC, SC, and TN) exhibit considerable year to year variability in production. Although the hydroclimatology of the Southeast U.S. has been analyzed partially, no previous study has linked the region's hydroelectricity production to any reported causes of interannual hydroclimatological variability, as has been completed in other regions. Due to the current short-term hydroelectricity production forecasts, the water resource is not optimized from a hydropower perspective as electricity generating potential is not maximized. The results of this study highlight the amount of untapped hydroelectricity that could be produced if long term hydroclimate and large-scale climate drivers were considered in production forecasts.

The multipurpose water use of hydropower reservoir: the SHARE concept

International Nuclear Information System (INIS)

Branche, E.

2017-01-01

Multipurpose hydropower reservoirs are designed and/or operated to provide services beyond electricity generation, such as water supply, flood and drought management, irrigation, navigation, fisheries, environmental services and recreational activities, etc. While these objectives (renewable and power services, water quantity management, ecosystem services, economic growth and local livelihoods) can conflict at times, they are also often complementary. Although there are no universal solutions, there are principles that can be shared and adapted to local contexts. Indeed the development and/or operation of such multipurpose hydropower reservoirs to reach sustainable water management should rely on the following principles: shared vision, shared resource, shared responsibilities, shared rights and risks, shared costs and benefits. These principles and acknowledgement of joint sharing among all the stakeholders are essential to successful development and management of multipurpose hydropower reservoirs, and should frame all phases from early stage to operation. The SHARE concept also gives guidance. Based on 12 worldwide case studies of multipurpose hydropower reservoirs, the SHARE concept was developed and proposed as a solution to address this issue. A special focus will be presented on the Durance-Verdon Rivers in France. (author)

Simultaneous measurement of tritium and radiocarbon by ultra-low-background proportional counting.

Science.gov (United States)

Mace, Emily; Aalseth, Craig; Alexander, Tom; Back, Henning; Day, Anthony; Hoppe, Eric; Keillor, Martin; Moran, Jim; Overman, Cory; Panisko, Mark; Seifert, Allen

2017-08-01

Use of ultra-low-background capabilities at Pacific Northwest National Laboratory provide enhanced sensitivity for measurement of low-activity sources of tritium and radiocarbon using proportional counters. Tritium levels are nearly back to pre-nuclear test backgrounds (~2-8 TU in rainwater), which can complicate their dual measurement with radiocarbon due to overlap in the beta decay spectra. We present results of single-isotope proportional counter measurements used to analyze a dual-isotope methane sample synthesized from ~120mg of H 2 O and present sensitivity results. Copyright © 2017 Elsevier Ltd. All rights reserved.

Development of ultra-low pressure reverse osmosis membranes; Choteiatsu gyakushintomaku no kaihatsu

Energy Technology Data Exchange (ETDEWEB)

Hirose, M.; Ito, H.; Ohara, T. [Nitto Denko Corp., Osaka (Japan)

1998-06-05

Described herein is development of ultra-low pressure reverse osmosis (RO) membranes. The composite RO membrane, which is now widely used, has a cross-sectional structure consisting of an ultrafilter membrane as the support and a very thin skin layer responsible for filtration. It is confirmed that the skin layer is of a pleated structure. Growing this structure can greatly accelerate permeation of water without damaging arresting and durability characteristics of the membrane, and hence is a desired approach. Utilization of molecular structure simulation of the skin layer materials is investigated by the molecular dynamics. The results show that the stable structure of the material for the skin layer in the RO membrane is a network structure with regularly arranged honeycombs, when it should arrest at least 99% of salt. These techniques serve as the bases for development of the ultra-low pressure RO membranes (ES Series), where the skin layer is made of cross-linked, totally aromatic polyamide. The membrane passes twice as large a quantity of water as the conventional one, is highly resistant to chemicals, and arrests 99.7% of salt. 3 refs., 4 figs.

Ultra compact 45 GHz CMOS compatible Germanium waveguide photodiode with low dark current.

Science.gov (United States)

DeRose, Christopher T; Trotter, Douglas C; Zortman, William A; Starbuck, Andrew L; Fisher, Moz; Watts, Michael R; Davids, Paul S

2011-12-05

We present a compact 1.3 × 4 μm2 Germanium waveguide photodiode, integrated in a CMOS compatible silicon photonics process flow. This photodiode has a best-in-class 3 dB cutoff frequency of 45 GHz, responsivity of 0.8 A/W and dark current of 3 nA. The low intrinsic capacitance of this device may enable the elimination of transimpedance amplifiers in future optical data communication receivers, creating ultra low power consumption optical communications.

Low cost RISC implementation of intelligent ultra fast charger for Ni-Cd battery

International Nuclear Information System (INIS)

Petchjatuporn, Panom; Sirisuk, Phaophak; Khaehintung, Noppadol; Sunat, Khamron; Wicheanchote, Phinyo; Kiranon, Wiwat

2008-01-01

This paper presents a low cost reduced instruction set computer (RISC) implementation of an intelligent ultra fast charger for a nickel-cadmium (Ni-Cd) battery. The charger employs a genetic algorithm (GA) trained generalized regression neural network (GRNN) as a key to ultra fast charging while avoiding battery damage. The tradeoff between mean square error (MSE) and the computational burden of the GRNN is addressed. Besides, an efficient technique is proposed for estimation of a radial basis function (RBF) in the GRNN. Hardware realization based upon the techniques is discussed. Experimental results with commercial Ni-Cd batteries reveal that while the proposed charger significantly reduces the charging time, it scarcely deteriorates the battery energy storage capability when compared with the conventional charger

Low cost RISC implementation of intelligent ultra fast charger for Ni-Cd battery

Energy Technology Data Exchange (ETDEWEB)

Petchjatuporn, Panom; Khaehintung, Noppadol [Department of Control and Instrumentation Engineering, Faculty of Engineering, Mahanakorn University of Technology, Bangkok 10530 (Thailand); Sirisuk, Phaophak; Sunat, Khamron [Department of Computer Engineering, Faculty of Engineering, Mahanakorn University of Technology, Bangkok 10530 (Thailand); Wicheanchote, Phinyo [Test Engineering Department, Sanmina-SCI Systems Co. Ltd. (Thailand); Kiranon, Wiwat [Department of Telecommunication Engineering, Faculty of Engineering, King Mongkut' s Institue of Technology, Ladkrabang, Bangkok 10520 (Thailand)

2008-02-15

This paper presents a low cost reduced instruction set computer (RISC) implementation of an intelligent ultra fast charger for a nickel-cadmium (Ni-Cd) battery. The charger employs a genetic algorithm (GA) trained generalized regression neural network (GRNN) as a key to ultra fast charging while avoiding battery damage. The tradeoff between mean square error (MSE) and the computational burden of the GRNN is addressed. Besides, an efficient technique is proposed for estimation of a radial basis function (RBF) in the GRNN. Hardware realization based upon the techniques is discussed. Experimental results with commercial Ni-Cd batteries reveal that while the proposed charger significantly reduces the charging time, it scarcely deteriorates the battery energy storage capability when compared with the conventional charger. (author)

Ultra-low damping in lift-off structured yttrium iron garnet thin films

Science.gov (United States)

Krysztofik, A.; Coy, L. E.; Kuświk, P.; Załeski, K.; Głowiński, H.; Dubowik, J.

2017-11-01

We show that using maskless photolithography and the lift-off technique, patterned yttrium iron garnet thin films possessing ultra-low Gilbert damping can be accomplished. The films of 70 nm thickness were grown on (001)-oriented gadolinium gallium garnet by means of pulsed laser deposition, and they exhibit high crystalline quality, low surface roughness, and the effective magnetization of 127 emu/cm3. The Gilbert damping parameter is as low as 5 ×10-4. The obtained structures have well-defined sharp edges which along with good structural and magnetic film properties pave a path in the fabrication of high-quality magnonic circuits and oxide-based spintronic devices.

A Hydropower Biological Evaluation Toolset (HBET) for Characterizing Hydraulic Conditions and Impacts of Hydro-Structures on Fish

Energy Technology Data Exchange (ETDEWEB)

Hou, Hongfei; Deng, Zhiqun; Martinez, Jayson; Fu, Tao; Duncan, Joanne; Johnson, Gary; Lu, Jun; Skalski, John; Townsend, Richard; Tan, Li

2018-04-01

Currently, approximately 16% of the world’s electricity and over 80% of the world’s renewable electricity is generated from hydropower resources, and there is potential for development of a significant amount of new hydropower capacity. However, in practice, realizing all the potential hydropower resource is limited by various factors, including environmental effects and related mitigation requirements. That is why hydropower regulatory requirements frequently call for targets to be met regarding fish injury and mortality rates. Hydropower Biological Evaluation Toolset (HBET), an integrated suite of software tools, is designed to characterize hydraulic conditions of hydropower structures and provide quantitative estimates of fish injury and mortality rates due to various physical stressors including strike, pressure, and shear. HBET enables users to design new studies, analyze data, perform statistical analyses, and evaluate biological responses. In this paper, we discuss the features of the HBET software and describe a case study that illustrates its functionalities. HBET can be used by turbine manufacturers, hydropower operators, and regulators to design and operate hydropower systems that minimize ecological impacts in a cost-effective manner.

75 FR 18193 - Northern Illinois Hydropower, LLC; Notice of Application Accepted for Filing and Soliciting...

Science.gov (United States)

2010-04-09

... Illinois Hydropower, LLC; Notice of Application Accepted for Filing and Soliciting Motions To Intervene and... No.: 12626-002. c. Date filed: March 31, 2009. d. Applicant: Northern Illinois Hydropower, LLC. e... Power Act, 16 U.S.C. 791(a)-825(r). h. Applicant Contact: Damon Zdunich, Northern Illinois Hydropower...

75 FR 24937 - Northern Illinois Hydropower, LLC; Notice of Application Accepted for Filing and Soliciting...

Science.gov (United States)

2010-05-06

... Illinois Hydropower, LLC; Notice of Application Accepted for Filing and Soliciting Motions To Intervene and... No.: 12717-002. c. Date filed: May 27, 2009. d. Applicant: Northern Illinois Hydropower, LLC. e. Name... Hydropower, LLC, 801 Oakland Avenue, Joliet, IL 60435, (312) 320-1610. i. FERC Contact: Dr. Nicholas Palso...

76 FR 12103 - Erie Boulevard Hydropower, L.P; Notice of Settlement Agreement and Soliciting Comments

Science.gov (United States)

2011-03-04

... Hydropower, L.P; Notice of Settlement Agreement and Soliciting Comments Take notice that the following... Boulevard Hydropower, L.P. e. Location: The existing multi-development project is located on the Oswegatchie... 791 (a)-825(r) h. Applicant Contact: Daniel Daoust, Erie Boulevard Hydropower, 33 West 1st Street...

Quantifying the Value of Hydropower in the Electric Grid: Final Report

Energy Technology Data Exchange (ETDEWEB)

Key, T. [Electric Power Research Inst. (EPRI), Knovville, TN (United States); Rogers, L. [Electric Power Research Inst. (EPRI), Knovville, TN (United States); Brooks, D. [Electric Power Research Inst. (EPRI), Knovville, TN (United States); Tuohy, A. [Electric Power Research Inst. (EPRI), Knovville, TN (United States)

2012-12-31

The report summarizes research to Quantify the Value of Hydropower in the Electric Grid. This 3-year DOE study focused on defining value of hydropower assets in a changing electric grid. Methods are described for valuation and planning of pumped storage and conventional hydropower. The project team conducted plant case studies, electric system modeling, market analysis, cost data gathering, and evaluations of operating strategies and constraints. Five other reports detailing these research results are available a project website, www.epri.com/hydrogrid. With increasing deployment of wind and solar renewable generation, many owners, operators, and developers of hydropower have recognized the opportunity to provide more flexibility and ancillary services to the electric grid. To quantify value of services, this study focused on the Western Electric Coordinating Council region. A security-constrained, unit commitment and economic dispatch model was used to quantify the role of hydropower for several future energy scenarios up to 2020. This hourly production simulation considered transmission requirements to deliver energy, including future expansion plans. Both energy and ancillary service values were considered. Addressing specifically the quantification of pumped storage value, no single value stream dominated predicted plant contributions in various energy futures. Modeling confirmed that service value depends greatly on location and on competition with other available grid support resources. In this summary, ten different value streams related to hydropower are described. These fell into three categories; operational improvements, new technologies, and electricity market opportunities. Of these ten, the study was able to quantify a monetary value in six by applying both present day and future scenarios for operating the electric grid. This study confirmed that hydropower resources across the United States contribute significantly to operation of the grid in terms

Achieving low return temperature for domestic hot water preparation by ultra-low-temperature district heating

DEFF Research Database (Denmark)

Yang, Xiaochen; Svendsen, Svend

2017-01-01

District heating (DH) is a cost-effective method of heat supply, especially to area with high heat density. Ultra-low-temperature district heating (ULTDH) is defined with supply temperature at 35-45 degrees C. It aims at making utmost use of the available low-temperature energy sources. In order...... to achieve high efficiency of the ULTDH system, the return temperature should be as low as possible. For the energy-efficient buildings in the future, it is feasible to use ULTDH to cover the space heating demand. However, considering the comfort and hygiene requirements of domestic hot water (DHW...... lower return temperature and higher efficiency for DHW supply, an innovative substation was devised, which replaced the bypass with an instantaneous heat exchanger and a micro electric storage tank. The energy performance of the proposed substation and the resulting benefits for the DH system...

The Second Assessment of the Effects of Climate Change on Federal Hydropower

Energy Technology Data Exchange (ETDEWEB)

Kao, Shih-Chieh [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Ashfaq, Moetasim [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Naz, Bibi S. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Uria Martinez, Rocio [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Rastogi, Deeksha [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Mei, Rui [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Jager, Yetta [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Samu, Nicole M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Sale, Michael J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2016-09-01

Hydropower is a key contributor to the US renewable energy portfolio due to its established development history and the diverse benefits it provides to the electric power system. Ensuring the sustainable operation of existing hydropower facilities is of great importance to the US renewable energy portfolio and the reliability of electricity grid. As directed by Congress in Section 9505 of the SECURE Water Act (SWA) of 2009 (Public Law 111-11), the US Department of Energy (DOE), in consultation with the federal Power Marketing Administrations (PMAs) and other federal agencies, has prepared a second quinquennial report on examining the potential effects of climate change on water available for hydropower at federal facilities and on the marketing of power from these federal facilities. This Oak Ridge National Laboratory (ORNL) Technical Memorandum, referred to as the 9505 assessment, describes the technical basis for the report to Congress that was called for in the SWA. To evaluate the potential climate change effects on 132 federal hydropower plants across the entire US, a spatially consistent assessment approach is designed to enable an interregional comparison. This assessment uses a series of models and methods with different spatial resolutions to gradually downscale the global climate change signals into watershed-scale hydrologic projections to support hydropower impact assessment. A variety of historic meteorological and hydrologic observations, hydropower facility characteristics, and geospatial datasets is collected to support model development, calibration, and verification. Among most of the federal hydropower plants throughout the US, the most important climate change effect on hydrology is likely to be the trend toward earlier snowmelt and change of runoff seasonality. Under the projections of increasing winter/spring runoff and decreasing summer/fall runoff, water resource managers may need to consider different water use allocations. With the

India's hydropower vision to 2030 - environmental issues

International Nuclear Information System (INIS)

Goel, R.S.

2004-01-01

The economic advantages of hydropower has been enhanced in the recent years with the steep increases in the energy costs from fossil fuel and the rapid approaching limits to the exploitable resources of such fuels. It is a matter of concern that the share of hydropower in the total installed capacity in India has been declining in successive plans. In the 1962-63, hydro projects had a 50% share in the total installed capacity which has declined to 24%. Such a dismal share of hydro thermal mix is adversely affecting the optimal utilisation of natural and financial resources besides resulting in failure of power grids. Even a layman can appreciate that in the situation of monsoonic weather the storage of river flows during floods is unavoidable not only to meet the basic needs of bulging population for diverse uses but also to moderate the floods, droughts and poverty. This article focuses on the environmental issues related to hydropower and river valley projects, while pinpointing the vital need of large storage projects in India. The water is becoming scarcer in India due to bulging population; but the environmental activism and biased media reporting are creating large scale obstructions in the execution of hydro projects

Comparative study of Ta, TaN and Ta/TaN bi-layer barriers for Cu-ultra low-k porous polymer integration

International Nuclear Information System (INIS)

Yang, L.Y.; Zhang, D.H.; Li, C.Y.; Foo, P.D.

2004-01-01

Tantalum (Ta), TaN and bilayer Ta/TaN barriers deposited on ultra-low-k porous polymer (ULKPP) and the thermal stability of their structures are comparatively investigated using various techniques. The Ta/ultra-low-k polymer shows the smallest sheet resistance, but the poorest thermal stability, while TaN on the ultra-low-k polymer shows the highest resistance but the best thermal stability. The bi-layer Ta/TaN barrier takes the advantage of both Ta and TaN barriers and gives reasonable resistance and thermal stability. The electrical tests indicate that the Cu lines with the TaN and bi-layer Ta/TaN barriers exhibit the smaller leakage current and higher breakdown voltage compared with the Cu lines with the Ta barrier. The better thermal stability of the TaN and the bi-layer Ta/TaN barriers is mainly due to the amorphous/nanostructure and less grain boundaries of the barriers. In addition, the texture discontinuity at the Ta/TaN interfaces in the bi-layers barrier also plays an important role in reducing mutual diffusion of Ta atoms in the Ta barrier and some atoms in the ultra-low-k porous polymer

Small and low head pumped storage projects

International Nuclear Information System (INIS)

Makarechian, A.H.

1991-01-01

The purpose of this paper is to focus attention on small and low head pumped storage projects. These projects may be defined as having a capacity of less than 200-300 MW and down to about 20 MW, with heads of 1200 ft to about 300 ft or less. Many advantages of these smaller pumped storage projects include more flexibility in siting of a project, considerably shorter licensing and construction period, adaptability to closed system design concept to reduce adverse environmental impacts, considerably reduced risks of delays and substantial cost over-runs, better suited to meeting peaking capacity requirements for individual utilities, and much less transmission inter-connection requirements. An overall licensing and construction schedule of about 3 to 3 1/2 years is realistic for many smaller pumped storage projects, and competitive costs in terms of dollars per kW installed can be achieved

The environmental impacts of peaking at hydropower plants

International Nuclear Information System (INIS)

Halleraker, Jo Halvard

2001-01-01

A recent energy act in Norway allows hydropower plants to be operated so that hydro peaking is permitted. However, it is uncertain how fish react to the variations in discharge and depth that follow hydro peaking. SINTEF Energy Research is cooperating with other research institutions to investigate the consequences of these variations on the biota. Among the research tools is an aqua channel which is an indoor laboratory flume where fish behaviour can be studied in detail. It has been constructed to provide the hydropower industry and public authorities with means of better determining the effects of hydro peaking. (author)

Impacts of climate change on water resources and hydropower systems in central and southern Africa

Energy Technology Data Exchange (ETDEWEB)

Hamududu, Byman H.

2012-11-15

Climate change is altering hydrological processes with varying degrees in various regions of the world. This research work investigates the possible impacts of climate change on water resource and Hydropower production potential in central and southern Africa. The Congo, Zambezi and Kwanza, Shire, Kafue and Kabompo basins that lie in central and southern Africa are used as case studies. The review of climate change impact studies shows that there are few studies on impacts of climate change on hydropower production. Most of these studies were carried out in Europe and north America and very few in Asia, south America and Africa. The few studies indicate that southern Africa would experience reduction in precipitation and runoff, consequently reductions in hydropower production. There are no standard methods of assessing the resulting impacts. Two approaches were used to assess the impacts of climate change on water resources and hydropower. One approach is lumping changes on country or regional level and use the mean climate changes on mean annual flows as the basis for regional changes in hydropower production. This is done to get an overall picture of the changes on global and regional level. The second approach is a detailed assessment process in which downscaling, hydrological modelling and hydropower simulations are carried out. The possible future climate scenarios for the region of central and southern Africa depicted that some areas where precipitation are likely to have increases while other, precipitation will reduce. The region northern Zambia and southern Congo showed increases while the northern Congo basin showed reductions. Further south in southern African region, there is a tendency of decreases in precipitation. To the west, in Angola, inland showed increases while towards the coast highlighted some decreases in precipitation. On a global scale, hydropower is likely to experience slight changes (0.08%) due to climate change by 2050. Africa is

77 FR 27451 - Boott Hydropower, Inc.; Notice of Section 106 Consultation Meeting

Science.gov (United States)

2012-05-10

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Project No. 2790-055] Boott Hydropower, Inc.; Notice of Section 106 Consultation Meeting On May 24, 2012, Federal Energy Regulatory Commission... Historic Preservation, Boott Hydropower, Inc., and any other consulting parties for the section 106 process...

A self-starting hybrid optoelectronic oscillator generating ultra low jitter 10-GHz optical pulses and low phase noise electrical signals

DEFF Research Database (Denmark)

Lasri, J.; Bilenca, A.; Dahan, D.

2002-01-01

In this letter, we describe a self-starting optical pulse source generating ultra low noise 15-ps-wide pulses at 10 GHz. It is based on a hybrid optoelectronic oscillator comprising a fiber extended cavity mode-locked diode laser which injection locks a self-oscillating heterojunction bipolar...

The role of hydropower in electric power integration of Asian countries

Science.gov (United States)

Belyaev, Lev; Savelyev, Vladimir; Chudinova, Lyudmila

2018-01-01

The possible role of hydropower plants in formation and operation of interstate power pools is described based on the generalization of the world experience. Peculiarities of the influence of hydropower on development of interstate electric ties in this part of the world and potential effects are showed on the example of Central and Northeast Asia.

Hydropower Manufacturing and Supply Chain Analysis

Energy Technology Data Exchange (ETDEWEB)

Cotrell, Jason R [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

2018-01-02

Hydropower Manufacturing and Supply Chain Analysis presentation from the WPTO FY14-FY16 Peer Review. The project objective is to provide data and insights to inform investment strategies, policy, and other decisions to promote economic growth and manufacturing.

The impact of global change on the hydropower potential of Europe: a model-based analysis

International Nuclear Information System (INIS)

Lehner, Bernhard; Czisch, Gregor; Vassolo, Sara

2005-01-01

This study presents a model-based approach for analyzing the possible effects of global change on Europe's hydropower potential at a country scale. By comparing current conditions of climate and water use with future scenarios, an overview is provided of today's potential for hydroelectricity generation and its mid- and long-term prospects. The application of the global water model WaterGAP for discharge calculations allows for an integrated assessment, taking both climate and socioeconomic changes into account. This study comprises two key parts: First, the 'gross' hydropower potential is analyzed, in order to outline the general distribution and trends in hydropower capabilities across Europe. Then, the assessment focuses on the 'developed' hydropower potential of existing hydropower plants, in order to allow for a more realistic picture of present and future electricity production. For the second part, a new data set has been developed which geo-references 5991 European hydropower stations and distinguishes them into run-of-river and reservoir stations. The results of this study present strong indications that, following moderate climate and global change scenario assumptions, severe future alterations in discharge regimes have to be expected, leading to unstable regional trends in hydropower potentials with reductions of 25% and more for southern and southeastern European countries

[Impacts of large hydropower station on benthic algal communities].

Science.gov (United States)

Jia, Xing-Huan; Jiang, Wan-Xiang; Li, Feng-Qing; Tang, Tao; Duan, Shu-Gui; Cai, Qing-Hua

2009-07-01

To investigate the impacts of large hydropower station in Gufu River on benthic algae, monthly samplings were conducted from September 2004 to June 2007 at the site GF04 which was impacted by the hydropower station, with the site GL03 in Gaolan River as reference. During sampling period, no significant differences were observed in the main physicochemical variables between GF04 and GL03, but the hydrodynamics differed significantly. GL03 was basically at a status of slow flow; while GF04, owing to the discharging from the reservoir, was at a riffle status during more than 60% of the sampling period. Such a difference in hydrodynamics induced significant differences in the community similarity of benthic algae and the relative abundance of unattached diatoms, erect diatoms, and stalked diatoms between GF04 and GL03, which could better reflect the impacts of irregular draw-off by large hydropower station on river eco-system.

The calculation interest for administration of hydropower in the long-term

International Nuclear Information System (INIS)

2005-01-01

A review of important findings in newer, economic literature on discount rate in the long term is presented. Based on this review, two questions relating to the administration of Norwegian hydropower resources are briefly discussed. Firstly, which discount rate should be used as basis when valuating the existent Norwegian hydropower plants? Secondly, how should the socio-economic discount rate for investments in hydro projects be determined compared relatively to other types of investments in the power sector? The main conclusion is that the existing rate for administration of hydropower need not be substituted. Neither theory nor empiricism provides a conclusive answer. Certain relevant aspects that may be further investigated are put forth (ml)

Diamond-coated probe head for measurements in the deep SOL and beyond

DEFF Research Database (Denmark)

Schrittwieser, R.; Xu, G. S.; Yan, Ning

We have tested two cylindrical graphite probe heads coated by a layer of electrically isolating UNCD (Ultra Nano-Crystalline Diamond) using a CVD (Chemical Vapour Deposition) method. The probe heads were mounted on the reciprocating probe manipulator of the Experimental Advanced Superconducting T...

Low velocity impact behaviour of ultra high strength concrete panels

Indian Academy of Sciences (India)

Ultra high strength concrete; panel; drop weight test; impact analysis;. ABAQUS. 1. Introduction. Ultra high strength concrete ... Knight (2012) investigated the dynamic behaviour of steel fibre reinforced concrete plates under impact loading with ...

Small hydropower in Southern Africa: an overview of five countries in the region

CSIR Research Space (South Africa)

Jonker Klunne, W

2013-08-01

Full Text Available dif- ferent sources, but is incomplete and inconsistent. This lack of information severely hampers the abili- ty to learn from past experiences and creates a bar- rier to the uptake of the technology (Gaul et al., 2010). 14 Journal of Energy... of lack of infor- mation by providing an overview of the status of small hydropower in five southern African countries. Defining small hydropower No internationally agreed definitions exist for the different sizes of hydropower. A generic distinction...

Advanced inflow forecasting for a hydropower plant in an Alpine hydropower regulated catchment - coupling of operational and hydrological forecasts

Science.gov (United States)

Tilg, Anna-Maria; Schöber, Johannes; Huttenlau, Matthias; Messner, Jakob; Achleitner, Stefan

2017-04-01

Hydropower is a renewable energy source which can help to stabilize fluctuations in the volatile energy market. Especially pumped-storage infrastructures in the European Alps play an important role within the European energy grid system. Today, the runoff of rivers in the Alps is often influenced by cascades of hydropower infrastructures where the operational procedures are triggered by energy market demands, water deliveries and flood control aspects rather than by hydro-meteorological variables. An example for such a highly hydropower regulated river is the catchment of the river Inn in the Eastern European Alps, originating in the Engadin (Switzerland). A new hydropower plant is going to be built as transboundary project at the boarder of Switzerland and Austria using the water of the Inn River. For the operation, a runoff forecast to the plant is required. The challenge in this case is that a high proportion of runoff is turbine water from an upstream situated hydropower cascade. The newly developed physically based hydrological forecasting system is mainly capable to cover natural hydrological runoff processes caused by storms and snow melt but can model only a small degree of human impact. These discontinuous parts of the runoff downstream of the pumped storage are described by means of an additional statistical model which has been developed. The main goal of the statistical model is to forecast the turbine water up to five days in advance. The lead time of the data driven model exceeds the lead time of the used energy production forecast. Additionally, the amount of turbine water is linked to the need of electricity production and the electricity price. It has been shown that especially the parameters day-ahead prognosis of the energy production and turbine inflow of the previous week are good predictors and are therefore used as input parameters for the model. As the data is restricted due to technical conditions, so-called Tobit models have been used to

Ultra-low thermal expansion realized in giant negative thermal expansion materials through self-compensation

Science.gov (United States)

Shen, Fei-Ran; Kuang, Hao; Hu, Feng-Xia; Wu, Hui; Huang, Qing-Zhen; Liang, Fei-Xiang; Qiao, Kai-Ming; Li, Jia; Wang, Jing; Liu, Yao; Zhang, Lei; He, Min; Zhang, Ying; Zuo, Wen-Liang; Sun, Ji-Rong; Shen, Bao-Gen

2017-10-01

Materials with zero thermal expansion (ZTE) or precisely tailored thermal expansion are in urgent demand of modern industries. However, the overwhelming majority of materials show positive thermal expansion. To develop ZTE or negative thermal expansion (NTE) materials as compensators has become an important challenge. Here, we present the evidence for the realization of ultra-low thermal expansion in Mn-Co-Ge-In particles. The bulk with the Ni2In-type hexagonal structure undergoes giant NTE owing to a martensitic magnetostructural transition. The major finding is that the thermal expansion behavior can be totally controlled by modulating the crystallinity degree and phase transition from atomic scale. Self-compensation effect leads to ultra-low thermal expansion with a linear expansion coefficient as small as +0.68 × 10-6/K over a wide temperature range around room temperature. The present study opens an avenue to reach ZTE particularly from the large class of giant NTE materials based on phase transition.

Ultra-low thermal expansion realized in giant negative thermal expansion materials through self-compensation

Directory of Open Access Journals (Sweden)

Fei-Ran Shen

2017-10-01

Full Text Available Materials with zero thermal expansion (ZTE or precisely tailored thermal expansion are in urgent demand of modern industries. However, the overwhelming majority of materials show positive thermal expansion. To develop ZTE or negative thermal expansion (NTE materials as compensators has become an important challenge. Here, we present the evidence for the realization of ultra-low thermal expansion in Mn–Co–Ge–In particles. The bulk with the Ni2In-type hexagonal structure undergoes giant NTE owing to a martensitic magnetostructural transition. The major finding is that the thermal expansion behavior can be totally controlled by modulating the crystallinity degree and phase transition from atomic scale. Self-compensation effect leads to ultra-low thermal expansion with a linear expansion coefficient as small as +0.68 × 10−6/K over a wide temperature range around room temperature. The present study opens an avenue to reach ZTE particularly from the large class of giant NTE materials based on phase transition.

DOE Hydropower Program biennial report 1992--1993 (with an updated annotated bibliography)

Energy Technology Data Exchange (ETDEWEB)

Cada, G.F.; Sale, M.J. [Oak Ridge National Lab., TN (United States); Francfort, J.E.; Rinehart, B.N.; Sommers, G.L. [EG and G Idaho, Inc., Idaho Falls, ID (United States)

1993-07-01

This report, the latest in a series of annual/biennial Hydropower Program reports sponsored by the US Department of Energy, summarizes the research and development and technology transfer activities of fiscal years 1992 and 1993. The report discusses the activities in the four areas of the hydropower program: Environmental research; resource assessment; research coat shared with industry; and technology transfer. The report also offers an annotated bibliography of reports pertinent to hydropower, written by persons in Federal and state agencies, cities, metropolitan water districts, irrigation companies, and public and independent utilities. Most reports are available from the National Technical Information Service.

Estimating the Effects of Climate Change on Federal Hydropower and Power Marketing

Energy Technology Data Exchange (ETDEWEB)

Sale, Michael J [ORNL; Kao, Shih-Chieh [ORNL; Uria Martinez, Rocio [ORNL; Wei, Yaxing [ORNL

2011-01-01

The U.S. Department of Energy is currently preparing an assessment of the effects of climate change on federal hydropower, as directed by Congress in Section 9505 of the Secure Water Act of 2009 (P.L. 111-11). This paper describes the assessment approach being used in a Report to Congress currently being prepared by Oak Ridge National Laboratory. The 9505 assessment will examine climate change effects on water available for hydropower operations and the future power supplies marketed from federal hydropower projects. It will also include recommendations from the Power Marketing Administrations (PMAs) on potential changes in operation or contracting practices that could address these effects and risks of climate change. Potential adaption and mitigation strategies will also be identified. Federal hydropower comprises approximately half of the U.S. hydropower portfolio. The results from the 9505 assessment will promote better understanding among federal dam owners/operators of the sensitivity of their facilities to water availability, and it will provide a basis for planning future actions that will enable adaptation to climate variability and change. The end-users of information are Congressional members, their staff, the PMAs and their customers, federal dam owners/operators, and the DOE Water Power Program.

Modeling Net Land Occupation of Hydropower Reservoirs in Norway for Use in Life Cycle Assessment.

Science.gov (United States)

Dorber, Martin; May, Roel; Verones, Francesca

2018-02-20

Increasing hydropower electricity production constitutes a unique opportunity to mitigate climate change impacts. However, hydropower electricity production also impacts aquatic and terrestrial biodiversity through freshwater habitat alteration, water quality degradation, and land use and land use change (LULUC). Today, no operational model exists that covers any of these cause-effect pathways within life cycle assessment (LCA). This paper contributes to the assessment of LULUC impacts of hydropower electricity production in Norway in LCA. We quantified the inundated land area associated with 107 hydropower reservoirs with remote sensing data and related it to yearly electricity production. Therewith, we calculated an average net land occupation of 0.027 m 2 ·yr/kWh of Norwegian storage hydropower plants for the life cycle inventory. Further, we calculated an adjusted average land occupation of 0.007 m 2 ·yr/kWh, accounting for an underestimation of water area in the performed maximum likelihood classification. The calculated land occupation values are the basis to support the development of methods for assessing the land occupation impacts of hydropower on biodiversity in LCA at a damage level.

Cystic Fibrosis: Are Volumetric Ultra-Low-Dose Expiratory CT Scans Sufficient for Monitoring Related Lung Disease?

DEFF Research Database (Denmark)

Loeve, Martine; Lequin, Maarten H; Bruijne, Marleen de

2009-01-01

Purpose: To assess whether chest computed tomography (CT) scores from ultra-low-dose end-expiratory scans alone could suffice for assessment of all cystic fibrosis (CF)-related structural lung abnormalities. Materials and Methods: In this institutional review board–approved study, 20 patients...... with CF aged 6–20 years (eight males, 12 females) underwent low-dose end-inspiratory CT and ultra-low-dose end-expiratory CT. Informed consent was obtained. Scans were randomized and scored by using the Brody-II CT scoring system to assess bronchiectasis, airway wall thickening, mucus plugging......-Altman plots. Results: Median age was 12.6 years (range, 6.3–20.3 years), median forced expiratory volume in 1 second was 100% (range, 46%–127%) of the predicted value, and median forced vital capacity was 99% (range, 61%–123%) of the predicted value. Very good agreement was observed between end...

Memorandum of Understanding for Hydropower Two-Year Progress Report

Energy Technology Data Exchange (ETDEWEB)

None

2012-04-01

On March 24, 2010, the Department of the Army (DOA) through the U.S. Army Corps of Engineers (USACE or Corps), the Department of Energy, and the Department of the Interior signed the Memorandum of Understanding (MOU) for Hydropower. The purpose of the MOU is to “help meet the nation’s needs for reliable, affordable, and environmentally sustainable hydropower by building a long-term working relationship, prioritizing similar goals, and aligning ongoing and future renewable energy development efforts.” This report documents efforts so far.

DOE Hydropower Program Biennial Report for FY 2005-2006

Energy Technology Data Exchange (ETDEWEB)

Sale, Michael J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Cada, Glenn F. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Acker, Thomas L. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Northern Arizona State Univ., Flagstaff, AZ (United States); Carlson, Thomas [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Dauble, Dennis D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hall, Douglas G. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

2006-07-01

This report describes the progress of the R&D conducted in FY 2005-2006 the under four program areas at the time: (1) Advanced Hydropower Technology (Large Turbine Field Testing, Water Use Optimization, and Improved Mitigation Practices); (2) Supporting Research and Testing (Environmental Performance Testing Methods, Computational and Physical Modeling, Instrumentation and Controls, and Environmental Analysis); (3) Systems Integration and Technology Acceptance (Hydro/Wind Integration, National Hydropower Collaborative, and Integration and Communications); and (4) Supporting Engineering and Analysis (Valuation Methods and Assessments and Characterization of Innovative Technology).

Socio environmental policy and populational resettlement in hydropower plants

International Nuclear Information System (INIS)

Regini Nuti, Mirian; Feitosa Garcia, Marcia

2003-01-01

This paper aims to discuss the resettlement process caused by hydropower plants considering the Brazilian Power Sector ongoing context It is based on the analysis of the hydropower plants that started operation phase in the last tem years There are 17 projects provoking the displacement of 21000 families The paper presents the resettlement modalities used in these projects Finally, the main aspects of the resettlement process in the last decade are focused in order to contribute to the Brazilian Power Sector Resettlement Guidelines improvement and actualization

Optimization of cascade hydropower system operation by genetic algorithm to maximize clean energy output

Directory of Open Access Journals (Sweden)

Aida Tayebiyan

2016-06-01

Full Text Available Background: Several reservoir systems have been constructed for hydropower generation around the world. Hydropower offers an economical source of electricity with reduce carbon emissions. Therefore, it is such a clean and renewable source of energy. Reservoirs that generate hydropower are typically operated with the goal of maximizing energy revenue. Yet, reservoir systems are inefficiently operated and manage according to policies determined at the construction time. It is worth noting that with little enhancement in operation of reservoir system, there could be an increase in efficiency of the scheme for many consumers. Methods: This research develops simulation-optimization models that reflect discrete hedging policy (DHP to manage and operate hydropower reservoir system and analyse it in both single and multireservoir system. Accordingly, three operational models (2 single reservoir systems and 1 multi-reservoir system were constructed and optimized by genetic algorithm (GA. Maximizing the total power generation in horizontal time is chosen as an objective function in order to improve the functional efficiency in hydropower production with consideration to operational and physical limitations. The constructed models, which is a cascade hydropower reservoirs system have been tested and evaluated in the Cameron Highland and Batang Padang in Malaysia. Results: According to the given results, usage of DHP for hydropower reservoir system operation could increase the power generation output to nearly 13% in the studied reservoir system compared to present operating policy (TNB operation. This substantial increase in power production will enhance economic development. Moreover, the given results of single and multi-reservoir systems affirmed that hedging policy could manage the single system much better than operation of the multi-reservoir system. Conclusion: It can be summarized that DHP is an efficient and feasible policy, which could be used

Evaluation of effect of low opening operation on increasing wear of bearing bushings of guide vanes used in hydropower plants

International Nuclear Information System (INIS)

Kim, Jong Sung; Kim, Se Na

2012-01-01

A guide vane plays a key role in controlling the flow rate of water supplied to the turbine of a hydropower plant. It has been reported that guide vane bearing bushings are subjected to considerable wear, which requires them to be maintained. An ancillary service such as frequency control and black start causes cyclic low opening operation of the guide vanes. It is empirically well known that such operation increases the wear rate of the guide vane bearing bushing. In this study, the effect of low opening operation on the increasing wear of the guide vane bearing bushing is quantitatively assessed via finite element flow analysis, finite element stress analysis, and relative wear evaluation. As a result of the assessment, it is identified that the pressure applied on the guide vane surface increases and the contact length between the outer surface of the guide vane stem and the inner surface of the bearing bushing decreases with a decrease in the opening of the guide vane. In addition, low opening of the guide vanes results in an increase in the relative wear owing to the generation of high contact pressure on the bearing bushing surfaces

75 FR 51258 - Boott Hydropower, Inc.; Eldred L Field Hydroelectric Facility Trust; Notice of Application for...

Science.gov (United States)

2010-08-19

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Project No. 2790-055] Boott Hydropower... Hydropower, Inc. and Eldred L Field Hydroelectric Facility Trust. e. Name of Project: Lowell Hydroelectric... Affairs Coordinator, Boott Hydropower, Inc., One Tech Drive, Suite 220, Andover, MA 01810. Tel: (978) 681...

Small hydropower station in Lavin - Preliminary study

International Nuclear Information System (INIS)

Merz, F.

2008-05-01

This illustrated final report for the Swiss Federal Office of Energy (SFOE) presents the results of a preliminary study regarding a proposed small hydropower installation on the alpine river Lavinuoz in Lavin, Switzerland. The geographical situation with mountains and glaciers in the catchment area of the proposed hydropower installation is discussed as are the appropriate water catchment installations. Possible dangers caused by avalanches and rock fall are examined. The power to be produced - 5,500,000 kWh/y - by the turbine which is nominally rated at 1350 kW is discussed, as are estimates of production costs. Figures on the investments required and the economic feasibility of the project are discussed, as are environmental factors that are to be taken into account.

The role of hydropower in meeting Turkey's electric energy demand

International Nuclear Information System (INIS)

Yuksek, Omer; Komurcu, Murat Ihsan; Yuksel, Ibrahim; Kaygusuz, Kamil

2006-01-01

The inherent technical, economic and environmental benefits of hydroelectric power, make it an important contributor to the future world energy mix, particularly in the developing countries. These countries, such as Turkey, have a great and ever-intensifying need for power and water supplies and they also have the greatest remaining hydro potential. From the viewpoint of energy sources such as petroleum and natural gas, Turkey is not a rich country; but it has an abundant hydropower potential to be used for generation of electricity and must increase hydropower production in the near future. This paper deals with policies to meet the increasing electricity demand for Turkey. Hydropower and especially small hydropower are emphasized as Turkey's renewable energy sources. The results of two case studies, whose results were not taken into consideration in calculating Turkey's hydro electric potential, are presented. Turkey's small hydro power potential is found to be an important energy source, especially in the Eastern Black Sea Region. The results of a study in which Turkey's long-term demand has been predicted are also presented. According to the results of this paper, Turkey's hydro electric potential can meet 33-46% of its electric energy demand in 2020 and this potential may easily and economically be developed

Specific gravity and API gravity of biodiesel and ultra-low sulfur diesel (ULSD) blends

Science.gov (United States)

Biodiesel is an alternative fuel made from vegetable oils and animal fats. In 2006, the U. S. Environmental Protection Agency mandated a maximum sulfur content of 15 ppm in on-road diesel fuels. Processing to produce the new ultra-low sulfur petrodiesel (ULSD) alters specific gravity (SG) and othe...

Finding Multiple Optimal Solutions to Optimal Load Distribution Problem in Hydropower Plant

Directory of Open Access Journals (Sweden)

Xinhao Jiang

2012-05-01

Full Text Available Optimal load distribution (OLD among generator units of a hydropower plant is a vital task for hydropower generation scheduling and management. Traditional optimization methods for solving this problem focus on finding a single optimal solution. However, many practical constraints on hydropower plant operation are very difficult, if not impossible, to be modeled, and the optimal solution found by those models might be of limited practical uses. This motivates us to find multiple optimal solutions to the OLD problem, which can provide more flexible choices for decision-making. Based on a special dynamic programming model, we use a modified shortest path algorithm to produce multiple solutions to the problem. It is shown that multiple optimal solutions exist for the case study of China’s Geheyan hydropower plant, and they are valuable for assessing the stability of generator units, showing the potential of reducing occurrence times of units across vibration areas.

Hydropower | Climate Neutral Research Campuses | NREL

Science.gov (United States)

project. Options usually include self-financing, issuing bonds, or obtaining third-party financing from how hydropower may fit into your climate action plans. Campus Options Considerations Sample Project to handle permitting issues? Does your campus need a hydraulics laboratory? Is financing available

78 FR 61958 - New England Hydropower Company, LLC; Notice of Preliminary Permit Application Accepted for Filing...

Science.gov (United States)

2013-10-08

... Hydropower Company, LLC; Notice of Preliminary Permit Application Accepted for Filing and Soliciting Comments, Motions To Intervene, and Competing Applications On August 20, 2013, the New England Hydropower Company... river are owned by the city of Meriden. Applicant Contact: Mr. Michael C. Kerr, New England Hydropower...

78 FR 66355 - Pleasant Grove City, UT; Notice of Preliminary Determination of a Qualifying Conduit Hydropower...

Science.gov (United States)

2013-11-05

... City, UT; Notice of Preliminary Determination of a Qualifying Conduit Hydropower Facility and... Grove City, Utah (Pleasant Grove) filed a notice of intent to construct a qualifying conduit hydropower facility, pursuant to section 30 of the Federal Power Act, as amended by section 4 of the Hydropower...

75 FR 7469 - Panel Member List for Hydropower Licensing Study Dispute Resolution; Notice Extending Filing Date...

Science.gov (United States)

2010-02-19

... List for Hydropower Licensing Study Dispute Resolution; Notice Extending Filing Date for Applications for Panel Member List for Hydropower Licensing Study Dispute Resolution February 4, 2010. On October... on a list of resource experts willing to serve as a third panel member in the Commission's hydropower...

78 FR 53752 - City of Sandpoint, Idaho; Notice of Preliminary Determination of a Qualifying Conduit Hydropower...

Science.gov (United States)

2013-08-30

... Sandpoint, Idaho; Notice of Preliminary Determination of a Qualifying Conduit Hydropower Facility and... intent to construct a qualifying conduit hydropower facility, pursuant to section 30 of the Federal Power Act, as amended by section 4 of the Hydropower Regulatory Efficiency Act of 2013 (HREA). The Little...

78 FR 61985 - City of Astoria, Oregon; Notice of Preliminary Determination of a Qualifying Conduit Hydropower...

Science.gov (United States)

2013-10-09

..., Oregon; Notice of Preliminary Determination of a Qualifying Conduit Hydropower Facility and Soliciting... of intent to construct a qualifying conduit hydropower facility, pursuant to section 30 of the Federal Power Act, as amended by section 4 of the Hydropower Regulatory Efficiency Act of 2013 (HREA). The...

Study on the Pressure Pulsation inside Runner with Splitter Blades in Ultra-High Head Turbine

International Nuclear Information System (INIS)

Meng, L; Zhang, S P; Zhou, L J; Wang, Z W

2014-01-01

Runners with splitter blades were used widely for the high efficiency and stability. In this paper, the unsteady simulation of an ultra-high head turbine at the best efficiency point, 50% and 75% discharge points were established, to analyze the pressure pulsation in the vaneless space, rotating domain and the draft tube. First of all, runners with different length splitter blades and without splitter blades were compared to learn the efficiency and the pressure distribution on the blade surface. And then the amplitude of the pressure pulsation was analysed. The peak efficiency of the runner with splitter blades is remarkably higher than that of the corresponding impeller without splitter blades. And the efficiency of the turbine is the highest when the length ratio of the splitter blades is 0.75 times the main blades. The pressure pulsation characteristics were also influenced, because the amplitudes of the pulsation induced by the RSI phenomenon were changed as a result of more blades. At last, the best design plan of the length of the splitter blades (length ratio=0.825) was obtained, which improved the pressure pulsation characteristics without significant prejudice to the efficiency

Renewable energy in pakistan: part-II mini/micro hydropower plants

International Nuclear Information System (INIS)

Maher, M.J.

2005-01-01

Part-1 of this series dealt with Wind-Energy Prospects in Pakistan. This second part gives a brief account Mini/Micro Hydro-Power Plants in Pakistan. Hydropower is well-known throughout the world and currently contributes 6-7% of total world energy-production and 20% of total world electricity generation. Most of the hydro-plants are usually designed for higher generation capacity than that which could be needed to utilize the average water-flows. Small hydro-plants are another potential source of energy among the non-conventional energy sources, which can reduce the load on conventional-energy production. Small hydropower technology is today a mature and proven technology. Civil works and installation of equipment involve simple process, which offer good opportunity to local people for employment and use locally available materials Nevertheless a small decentralized hydel plant, based on natural waterfalls is a very desirable option for geographically remote, but naturally suitable locations which are otherwise far from the national physical infrastructure. The development of Mini/Micro hydel stations in these areas, with isolated, thinly clustered, population, is a very appropriate solution to meet power-needs of such areas for lighting as well as cottage industry. The unique feature of these installations is the participation of local community to the optimum extent. The entire civil works, the intake system, power channel, forebay, penstock and power house building, as well as labour is provided by the inhabitants voluntarily. While maximum use is made of stone, with minimum use of cement, the generator, distribution wires, etc., need to be arranged from the market. The turbine is manufactured using indigenous materials. The installation-cost per KW is relatively low i.e. Rs. 25,000/- as compared to large-scale installations. There could of course be variations, in the installation-cost, depending on the market prices of the material. (author)

Trans, Switzerland: new drinking-water hydropower station; Gemeinde Trans (GR) - Neubau Trinkwasserkraftwerk - Bauprojekt

Energy Technology Data Exchange (ETDEWEB)

Gadient, N.; Scherrer, I.

2008-10-15

This report for the Swiss Federal Office of Energy (SFOE) presents the construction project for the realisation of a hydropower installation that uses the water of the drinking-water mains in Trans, Grisons, Switzerland, to generate electricity. Figures are presented on the head of water available, the proposed electrical power to be installed as well as the annual production and the financing of the project. The latter has been assured by the Swiss scheme for the cost-covering remuneration of electrical energy generated using renewable resources. The construction project agreed on is described and discussed. The project is to be realised together with the refurbishment of the existing drinking-water supply system. The installations necessary and the proposed electromechanical equipment are described and discussed. Also, the supply of increased amounts of water for fire-fighting purposes are noted.

Hydropower plans in eastern and southern Africa increase risk of concurrent climate-related electricity supply disruption

Science.gov (United States)

Conway, Declan; Dalin, Carole; Landman, Willem A.; Osborn, Timothy J.

2017-12-01

Hydropower comprises a significant and rapidly expanding proportion of electricity production in eastern and southern Africa. In both regions, hydropower is exposed to high levels of climate variability and regional climate linkages are strong, yet an understanding of spatial interdependences is lacking. Here we consider river basin configuration and define regions of coherent rainfall variability using cluster analysis to illustrate exposure to the risk of hydropower supply disruption of current (2015) and planned (2030) hydropower sites. Assuming completion of the dams planned, hydropower will become increasingly concentrated in the Nile (from 62% to 82% of total regional capacity) and Zambezi (from 73% to 85%) basins. By 2030, 70% and 59% of total hydropower capacity will be located in one cluster of rainfall variability in eastern and southern Africa, respectively, increasing the risk of concurrent climate-related electricity supply disruption in each region. Linking of nascent regional electricity sharing mechanisms could mitigate intraregional risk, although these mechanisms face considerable political and infrastructural challenges.

Ultra-low power anti-crosstalk collision avoidance light detection and ranging using chaotic pulse position modulation approach

International Nuclear Information System (INIS)

Hao Jie; Gong Ma-li; Du Peng-fei; Lu Bao-jie; Zhang Fan; Zhang Hai-tao; Fu Xing

2016-01-01

A novel concept of collision avoidance single-photon light detection and ranging (LIDAR) for vehicles has been demonstrated, in which chaotic pulse position modulation is applied on the transmitted laser pulses for robust anti-crosstalk purposes. Besides, single-photon detectors (SPD) and time correlated single photon counting techniques are adapted, to sense the ultra-low power used for the consideration of compact structure and eye safety. Parameters including pulse rate, discrimination threshold, and number of accumulated pulses have been thoroughly analyzed based on the detection requirements, resulting in specified receiver operating characteristics curves. Both simulation and indoor experiments were performed to verify the excellent anti-crosstalk capability of the presented collision avoidance LIDAR despite ultra-low transmitting power. (paper)

Nanocrystals manufacturing by ultra-low-energy ion-beam-synthesis for non-volatile memory applications

Energy Technology Data Exchange (ETDEWEB)

Normand, P. E-mail: p.normand@imel.demokritos.gr; Kapetanakis, E.; Dimitrakis, P.; Skarlatos, D.; Beltsios, K.; Tsoukalas, D.; Bonafos, C.; Ben Assayag, G.; Cherkashin, N.; Claverie, A.; Berg, J.A. van den; Soncini, V.; Agarwal, A.; Ameen, M.; Perego, M.; Fanciulli, M

2004-02-01

An overview of recent developments regarding the fabrication and structure of thin silicon dioxide films with embedded nanocrystals through ultra-low-energy ion-beam-synthesis (ULE-IBS) is presented. Advances in fabrication, increased understanding of structure formation processes and ways to control them allow for the fabrication of reproducible and attractive silicon-nanocrystal memory devices for a wide-range of memory applications as herein demonstrated in the case of low-voltage EEPROM-like applications.

Nanocrystals manufacturing by ultra-low-energy ion-beam-synthesis for non-volatile memory applications

International Nuclear Information System (INIS)

Normand, P.; Kapetanakis, E.; Dimitrakis, P.; Skarlatos, D.; Beltsios, K.; Tsoukalas, D.; Bonafos, C.; Ben Assayag, G.; Cherkashin, N.; Claverie, A.; Berg, J.A. van den; Soncini, V.; Agarwal, A.; Ameen, M.; Perego, M.; Fanciulli, M.

2004-01-01

An overview of recent developments regarding the fabrication and structure of thin silicon dioxide films with embedded nanocrystals through ultra-low-energy ion-beam-synthesis (ULE-IBS) is presented. Advances in fabrication, increased understanding of structure formation processes and ways to control them allow for the fabrication of reproducible and attractive silicon-nanocrystal memory devices for a wide-range of memory applications as herein demonstrated in the case of low-voltage EEPROM-like applications

A review of Environmental Impact Assessment parameters required for set up of a hydropower project

International Nuclear Information System (INIS)

Roy, Pankaj Kumar; Mazumdar, Asis

2013-01-01

Environmental Impact Assessment in general, hydro-meteorological conditions, topography, hydrology, water availability analysis of a river system, importance of hydropower and feasibility study of Environmental Impact assessment due to the construction of the hydropower plant have been discussed in this research work. The site selection is one of the major components so far the hydropower is concerned and also the minimum flow should have known to us so that the capacity of a hydropower plant can be predicted. The sustainable flow, which refers the flow is available throughout the year, has been calculated based on flow duration curve. This study highlights the environmental impact assessment particularly related to hydropower project. Here the study area a district town located in the eastern region of India on the banks of river Kosi has been considered. The historical rainfall and the river discharge data have been collected from various organizations. The stage-discharge correlation and hydrological parameters related to hydropower have been analyzed and also to discuss the review of environmental impact assessment in hydropower project. The EIA analysis can be also carried out by using fuzzy logic wherein the EIA parameters can be given different weight-age based on the various survey reports that have been carried out at different places at different time. Such analysis has also been provided below based on the various data obtained.

A multi-scale spatial approach to address environmental effects of small hydropower development.

Science.gov (United States)

McManamay, Ryan A; Samu, Nicole; Kao, Shih-Chieh; Bevelhimer, Mark S; Hetrick, Shelaine C

2015-01-01

Hydropower development continues to grow worldwide in developed and developing countries. While the ecological and physical responses to dam construction have been well documented, translating this information into planning for hydropower development is extremely difficult. Very few studies have conducted environmental assessments to guide site-specific or widespread hydropower development. Herein, we propose a spatial approach for estimating environmental effects of hydropower development at multiple scales, as opposed to individual site-by-site assessments (e.g., environmental impact assessment). Because the complex, process-driven effects of future hydropower development may be uncertain or, at best, limited by available information, we invested considerable effort in describing novel approaches to represent environmental concerns using spatial data and in developing the spatial footprint of hydropower infrastructure. We then use two case studies in the US, one at the scale of the conterminous US and another within two adjoining rivers basins, to examine how environmental concerns can be identified and related to areas of varying energy capacity. We use combinations of reserve-design planning and multi-metric ranking to visualize tradeoffs among environmental concerns and potential energy capacity. Spatial frameworks, like the one presented, are not meant to replace more in-depth environmental assessments, but to identify information gaps and measure the sustainability of multi-development scenarios as to inform policy decisions at the basin or national level. Most importantly, the approach should foster discussions among environmental scientists and stakeholders regarding solutions to optimize energy development and environmental sustainability.

2014 Water Power Program Peer Review: Hydropower Technologies, Compiled Presentations (Presentation)

Energy Technology Data Exchange (ETDEWEB)

2014-02-01

This document represents a collection of all presentations given during the EERE Wind and Water Power Program's 2014 Hydropower Peer Review. The purpose of the meeting was to evaluate DOE-funded hydropower and marine and hydrokinetic R&D projects for their contribution to the mission and goals of the Water Power Program and to assess progress made against stated objectives.

Low earth orbit radiation dose distribution in a phantom head

International Nuclear Information System (INIS)

Konradi, A.; Badhwar, G.D.; Cash, B.L.; Hardy, K.A.

1992-01-01

In order to compare analytical methods with data obtained during exposure to space radiation, a phantom head instrumented with a large number of radiation detectors was flown on the Space Shuttle on three occasions: 8 August 1989 (STS-28), 28 February 1990 (STS-36), and 24 April 1990 (STS-31). The objective of this experiment was to obtain a measurement of the inhomogeneity in the dose distribution within a phantom head volume. The orbits of these missions were complementary-STS-28 and STS-36 had high inclination and low altitude, while STS-31 had a low inclination and high altitude. In the cases of STS-28 and STS-36, the main contribution to the radiation dose comes from galactic cosmic rays (GCR) with a minor to negligible part supplied by the inner belt through the South Atlantic Anomaly (SAA), and for STS-28 an even smaller one from a proton enhancement during a solar flare-associated proton event. For STS-31, the inner belt protons dominate and the GCR contribution is almost negligible. The internal dose distribution is consistent with the mass distribution of the orbiter and the self-shielding and physical location of the phantom head. (author)

Water, energy and agricultural landuse trends at Shiroro hydropower station and environs

Science.gov (United States)

Adegun, Olubunmi; Ajayi, Olalekan; Badru, Gbolahan; Odunuga, Shakirudeen

2018-02-01

The study examines the interplay among water resources, hydropower generation and agricultural landuse at the Shiroro hydropower station and its environs, in north-central Nigeria. Non-parametric trend analysis, hydropower footprint estimation, reservoir performance analysis, change detection analysis, and inferential statistics were combined to study the water-energy and food security nexus. Results of Mann-Kendall test and Sen's slope estimator for the period 1960 to 2013 showed a declining rainfall trend at Jos, around River Kaduna headwaters at -2.6 mm yr-1, while rainfall at Kaduna and Minna upstream and downstream of the reservoir respectively showed no trend. Estimates of hydropower footprint varied between 130.4 and 704.1 m3 GJ-1 between 1995 and 2013. Power generation reliability and resilience of the reservoir was 31.6 and 38.5 % respectively with year 2011 being the most vulnerable and least satisfactory. In addition to poor reliability and resilience indices, other challenges militating against good performance of hydropower generation includes population growth and climate change issues as exemplified in the downward trend observed at the headwaters. Water inflow and power generation shows a weak positive relationship with correlation coefficient (r) of 0.48, indicating less than optimal power generation. Total area of land cultivated increased from 884.59 km2 in 1986 prior to the commissioning of the hydropower station to 1730.83 km2 in 2016 which signifies an increased contribution of the dam to ensuring food security. The reality of reducing upstream rainfall amount coupled with high water footprint of electricity from the reservoir, therefore requires that a long term roadmap to improve operational coordination and management have to be put in place.

Socio-environmental integration of hydropower facilities

International Nuclear Information System (INIS)

Harby, Atle; Forseth, Torbjoern; Ruud, Audun; Bakken, Tor Haakon

2017-01-01

Centre for Environmental Design of Renewable Energy (CEDREN) is a research centre focusing on hydropower production and environmental impacts of hydropower. The main objective of CEDREN is to develop and communicate design solutions for renewable energy production that address environmental and societal challenges at local, regional, national and global levels. Environmental design means that planning, building and operation have to include technical, economic, environmental and socio-political aspects throughout the whole life-span of the project. Methods and tools to ensure environmental design are developed in CEDREN and applied to case studies in Norway and internationally. These methods and tools focus on finding physical and biological bottlenecks for affected species and ecosystems by mapping, modelling and analysis of both physical conditions and ecological status. CEDREN proposes different measures, tools and methods to improve the environmental conditions as well as how to maintain or increase the power production. In addition, a strong focus must be made on political governance to ensure more representative participation of relevant stakeholders in the process of finding the best technical, economic and political solutions for power production, the environment and the society. Key research findings used to develop relationships between physical factors like flow, flow fluctuations, water temperature, water velocity, water depth and water-covered area and biological response will be shown. Examples of improved methods for better planning procedures with stakeholder engagement will be proposed. Examples of methods and tools for environmental design of hydropower will be given for several regulated rivers in Norway and abroad. (authors)

78 FR 56872 - City of Barre, Vermont; Notice of Preliminary Determination of a Qualifying Conduit Hydropower...

Science.gov (United States)

2013-09-16

..., Vermont; Notice of Preliminary Determination of a Qualifying Conduit Hydropower Facility and Soliciting... construct a qualifying conduit hydropower facility, pursuant to section 30 of the Federal Power Act, as amended by section 4 of the Hydropower Regulatory Efficiency Act of 2013 (HREA). The Nelson Street 17 kW...

76 FR 7835 - Great River Hydropower, LLC; Notice of Scoping Meetings and Environmental Site Review and...

Science.gov (United States)

2011-02-11

... Hydropower, LLC; Notice of Scoping Meetings and Environmental Site Review and Soliciting Scoping Comments.... c. Date filed: July 12, 2010. d. Applicant: Great River Hydropower, LLC. e. Name of Project: Upper... 796-foot-long by 46-foot-wide by 25-foot-high concrete hydropower structure consisting of 30 turbine...

75 FR 10230 - Inglis Hydropower, LLC; Notice of Application Accepted for Filing and Soliciting Motions To...

Science.gov (United States)

2010-03-05

... Hydropower, LLC; Notice of Application Accepted for Filing and Soliciting Motions To Intervene and Protests... No.: P-12783-003. c. Date filed: July 22, 2009. d. Applicant: Inglis Hydropower, LLC. e. Name of Project: Inglis Hydropower Project. f. Location: The proposed project would be located at the existing...

Ultra-low-pressure sputtering to improve exchange bias and tune linear ranges in spin valves

Energy Technology Data Exchange (ETDEWEB)

Tang, XiaoLi, E-mail: tangtang1227@163.com; Yu, You; Liu, Ru; Su, Hua; Zhang, HuaiWu; Zhong, ZhiYong; Jing, YuLan

2017-05-01

A series of CoFe/IrMn exchange bilayers was grown by DC-sputtering at different ultra-low argon pressures ranging from 0.008 to 0.1 Pa. This pressure range was one to two orders lower than the normal sputtering pressure. Results revealed that the exchange bias increased from 140 to 250 Oe in CoFe(10 nm)/IrMn (15 nm) bilayers of fixed thickness because of the improved crystalline structure and morphological uniformity of films. Since ferromagnetic /antiferromagnetic (FM/AF) bilayers are always used in linear magnetic sensors as detection layers, the varying exchange bias can successfully achieve tunable linear range in a crossed pinning spin valve. The linear range could be adjustable from −80 Oe – +80 Oe to −150 Oe – +150 Oe on the basis of giant magnetoresistance responses. Therefore, this method provides a simple method to tune the operating range of magnetic field sensors. - Highlights: • Increasing exchange bias was achieved in bilayer at ultra-low-pressure sputtering. • The low void density and smooth surface were achieved in low pressure. • Varying exchange bias achieved tunable linear range in spin valve.

Estimated cumulative sediment trapping in future hydropower reservoirs in Africa

Science.gov (United States)

Lucía, Ana; Berlekamp, Jürgen; Zarfl, Christiane

2017-04-01

Despite a rapid economic development in Sub-Saharan Africa, almost 70% of the human population in this area remain disconnected from electricity access (International Energy Agency 2011). Mitigating climate change and a search for renewable, "climate neutral" electricity resources are additional reasons why Africa will be one key centre for future hydropower dam building, with only 8% of the technically feasible hydropower potential actually exploited. About 300 major hydropower dams with a total capacity of 140 GW are currently under construction (11.4%) or planned (88.6%) (Zarfl et al. 2015). Despite the benefits of hydropower dams, fragmentation of the rivers changes the natural flow, temperature and sediment regime. This has consequences for a high number of people that directly depend on the primary sector linked to rivers and floodplains. But sediment trapping in the reservoir also affects dam operation and decreases its life span. Thus, the objective of this work is to quantify the dimension of sediment trapping by future hydropower dams in African river basins. Soil erosion is described with the universal soil loss equation (Wischmeier & Smith 1978) and combined with the connectivity index (Cavalli et al. 2013) to estimate the amount of eroded soil that reaches the fluvial network and finally ends up in the existing (Lehner et al. 2011) and future reservoirs (Zarfl et al. 2015) per year. Different scenarios assuming parameter values from the literature are developed to include model uncertainty. Estimations for existing dams will be compared with literature data to evaluate the applied estimation method and scenario assumptions. Based on estimations for the reservoir volume of the future dams we calculated the potential time-laps of the future reservoirs due to soil erosion and depending on their planned location. This approach could support sustainable decision making for the location of future hydropower dams. References Cavalli, M., Trevisani, S., Comiti

DOE Hydropower Program biennial report 1994--1995 with an updated annotated bibliography

Energy Technology Data Exchange (ETDEWEB)

Rinehart, B.N.; Francfort, J.E.; Sommers, G.L. [Lockheed Idaho Technologies Co., Idaho Falls, ID (United States); Cada, G.F.; Sale, M.J. [Oak Ridge National Lab., TN (United States)

1995-05-01

This report, the latest in a series of annual/biennial Hydropower Program reports sponsored by the US Department of Energy, summarizes the research and development and technology transfer activities of fiscal years 1994 and 1995. The report discusses the activities in the four areas of the hydropower program: Environmental Research; Resource Assessment; Research Cost-Shared with Industry; and Technology Transfer. The report also includes an annotated bibliography of reports pertinent to hydropower, written by the staff of the Idaho National Engineering Laboratory, Oak Ridge National Laboratory, Federal and state agencies, cities, metropolitan water districts, irrigation companies, and public and independent utilities. Most reports are available from the National Technical Information Service.

DOE Hydropower Program biennial report 1994--1995 with an updated annotated bibliography

International Nuclear Information System (INIS)

Rinehart, B.N.; Francfort, J.E.; Sommers, G.L.; Cada, G.F.; Sale, M.J.

1995-05-01

This report, the latest in a series of annual/biennial Hydropower Program reports sponsored by the US Department of Energy, summarizes the research and development and technology transfer activities of fiscal years 1994 and 1995. The report discusses the activities in the four areas of the hydropower program: Environmental Research; Resource Assessment; Research Cost-Shared with Industry; and Technology Transfer. The report also includes an annotated bibliography of reports pertinent to hydropower, written by the staff of the Idaho National Engineering Laboratory, Oak Ridge National Laboratory, Federal and state agencies, cities, metropolitan water districts, irrigation companies, and public and independent utilities. Most reports are available from the National Technical Information Service

78 FR 62322 - Hydropower Regulatory Efficiency Act of 2013; Notice of Rescheduled Two-Year Licensing Process...

Science.gov (United States)

2013-10-16

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. AD13-9-000] Hydropower... recommendations on the feasibility of a two-year process for the issuance of a license for hydropower development... Hydropower Regulatory Efficiency Act of 2013. The workshop will be held in the Commission Meeting Room at 888...

Remote Sensing Extraction of Stopes and Tailings Ponds in AN Ultra-Low Iron Mining Area

Science.gov (United States)

Ma, B.; Chen, Y.; Li, X.; Wu, L.

2018-04-01

With the development of economy, global demand for steel has accelerated since 2000, and thus mining activities of iron ore have become intensive accordingly. An ultra-low-grade iron has been extracted by open-pit mining and processed massively since 2001 in Kuancheng County, Hebei Province. There are large-scale stopes and tailings ponds in this area. It is important to extract their spatial distribution information for environmental protection and disaster prevention. A remote sensing method of extracting stopes and tailings ponds is studied based on spectral characteristics by use of Landsat 8 OLI imagery and ground spectral data. The overall accuracy of extraction is 95.06 %. In addition, tailings ponds are distinguished from stopes based on thermal characteristics by use of temperature image. The results could provide decision support for environmental protection, disaster prevention, and ecological restoration in the ultra-low-grade iron ore mining area.

78 FR 79433 - Mahoning Hydropower, LLC, Ohio, Notice of Availability of Environmental Assessment

Science.gov (United States)

2013-12-30

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Project No. 13953-002] Mahoning Hydropower, LLC, Ohio, Notice of Availability of Environmental Assessment In accordance with the National... Hydropower, LLC's application for a license to construct, operate, and maintain the Lake Milton Hydroelectric...

Determining the effect of key climate drivers on global hydropower production

Science.gov (United States)

Galelli, S.; Ng, J. Y.; Lee, D.; Block, P. J.

2017-12-01

Accounting for about 17% of total global electrical power production, hydropower is arguably the world's main renewable energy source and a key asset to meet Paris climate agreements. A key component of hydropower production is water availability, which depends on both precipitation and multiple drivers of climate variability acting at different spatial and temporal scales. To understand how these drivers impact global hydropower production, we study the relation between four patterns of ocean-atmosphere climate variability (i.e., El Niño Southern Oscillation, Pacific Decadal Oscillation, North Atlantic Oscillation, and Atlantic Multidecadal Oscillation) and monthly time series of electrical power production for over 1,500 hydropower reservoirs—obtained via simulation with a high-fidelity dam model forced with 20th century climate conditions. Notably significant relationships between electrical power productions and climate variability are found in many climate sensitive regions globally, including North and South America, East Asia, West Africa, and Europe. Coupled interactions from multiple, simultaneous climate drivers are also evaluated. Finally, we highlight the importance of using these climate drivers as an additional source of information within reservoir operating rules where the skillful predictability of inflow exists.

Single-mode optical fiber design with wide-band ultra low bending-loss for FTTH application.

Science.gov (United States)

Watekar, Pramod R; Ju, Seongmin; Han, Won-Taek

2008-01-21

We propose a new design of a single-mode optical fiber (SMF) which exhibits ultra low bend sensitivity over a wide communication band (1.3 microm to 1.65 microm). A five-cladding fiber structure has been proposed to minimize the bending loss, estimated to be as low as 4.4x10(-10) dB/turn for the bend radius of 10 mm.

Ultra-low-frequency electromagnetic waves in the Earth's crust and magnetosphere

International Nuclear Information System (INIS)

Guglielmi, A V

2007-01-01

Research on natural intra- and extraterrestrially produced electromagnetic waves with periods ranging from 0.2 to 600 s is reviewed. The way in which the energy of rock movements transforms into the energy of an alternating magnetic field is analyzed. Methods for detecting seismomagnetic signals against a strong background are described. In discussing the physics of ultra-low-frequency waves in the magnetosphere, the 11-year activity modulation of 1-Hz waves and ponderomotive forces affecting plasma distribution are emphasized. (reviews of topical problems)

Frequency Stability of Hierarchically Controlled Hybrid Photovoltaic-Battery-Hydropower Microgrids

DEFF Research Database (Denmark)

Guan, Yajuan; Vasquez, Juan Carlos; Guerrero, Josep M.

2014-01-01

Hybrid photovolvaic battery-hydropower microgrids can increase electricity accessibility and availability in remote areas. In those microgrids with grid-connected and islanded modes capabilities, seamless transition between both modes is needed as well. However, the different resources with conve......Hybrid photovolvaic battery-hydropower microgrids can increase electricity accessibility and availability in remote areas. In those microgrids with grid-connected and islanded modes capabilities, seamless transition between both modes is needed as well. However, the different resources...

Component Development to Accelerate Commercial Implementation of Ultra-Low Emissions Catalytic Combustion

Energy Technology Data Exchange (ETDEWEB)

McCarty, Jon; Berry, Brian; Lundberg, Kare; Anson, Orris

2003-03-31

This final report describes a 2000-2003 program for the development of components and processes to enhance the commercialization of ultra-low emissions catalytic combustion in industrial gas turbines. The range of project tasks includes: development of more durable, lower-cost catalysts and catalytic combustor components; development and design of a catalytic pre-burner and a catalytic pilot burner for gas turbines, and on-site fuel conversion processing for utilization of liquid fuel.

The PS 200 catching trap: A new tool for ultra-low energy antiproton physics

International Nuclear Information System (INIS)

Holzscheiter, M.H.; Dyer, P.L.; King, N.S.P.; Lizon, D.C.; Morgan, G.L.; Schauer, M.M.; Schecker, J.A.; Hoibraten, S.; Lewis, R.A.; Otto, T.

1994-01-01

Approximately one million antiprotons have been trapped and electron cooled in the PS200 catching trap from a single fast extracted pulse from LEAR. The system is described in detail, different extraction schemes are discussed, and possible applications of this instrument to ultra-low energy atomic and nuclear physics with antiprotons are mentioned

Establishment and evaluation of operation function model for cascade hydropower station

OpenAIRE

Chang-ming Ji; Ting Zhou; Hai-tao Huang

2010-01-01

Toward solving the actual operation problems of cascade hydropower stations under hydrologic uncertainty, this paper presents the process of extraction of statistical characteristics from long-term optimal cascade operation, and proposes a monthly operation function algorithm for the actual operation of cascade hydropower stations through the identification, processing, and screening of available information during long-term optimal operation. Applying the operation function to the cascade hy...

Treatise on water hammer in hydropower standards and guidelines

International Nuclear Information System (INIS)

Bergant, A; Mazij, J; Karney, B; Pejović, S

2014-01-01

This paper reviews critical water hammer parameters as they are presented in official hydropower standards and guidelines. A particular emphasize is given to a number of IEC standards and guidelines that are used worldwide. The paper critically assesses water hammer control strategies including operational scenarios (closing and opening laws), surge control devices (surge tank, pressure regulating valve, flywheel, etc.), redesign of the water conveyance system components (tunnel, penstock), or limitation of operating conditions (limited operating range) that are variably covered in standards and guidelines. Little information is given on industrial water hammer models and solutions elsewhere. These are briefly introduced and discussed in the light of capability (simple versus complex systems), availability of expertise (in house and/or commercial) and uncertainty. The paper concludes with an interesting water hammer case study referencing the rules and recommendations from existing hydropower standards and guidelines in a view of effective water hammer control. Recommendations are given for further work on development of a special guideline on water hammer (hydraulic transients) in hydropower plants

Treatise on water hammer in hydropower standards and guidelines

Science.gov (United States)

Bergant, A.; Karney, B.; Pejović, S.; Mazij, J.

2014-03-01

This paper reviews critical water hammer parameters as they are presented in official hydropower standards and guidelines. A particular emphasize is given to a number of IEC standards and guidelines that are used worldwide. The paper critically assesses water hammer control strategies including operational scenarios (closing and opening laws), surge control devices (surge tank, pressure regulating valve, flywheel, etc.), redesign of the water conveyance system components (tunnel, penstock), or limitation of operating conditions (limited operating range) that are variably covered in standards and guidelines. Little information is given on industrial water hammer models and solutions elsewhere. These are briefly introduced and discussed in the light of capability (simple versus complex systems), availability of expertise (in house and/or commercial) and uncertainty. The paper concludes with an interesting water hammer case study referencing the rules and recommendations from existing hydropower standards and guidelines in a view of effective water hammer control. Recommendations are given for further work on development of a special guideline on water hammer (hydraulic transients) in hydropower plants.

World Small Hydropower Development Report 2013 - Zimbabwe

CSIR Research Space (South Africa)

Jonker Klunne, W

2013-01-01

Full Text Available in 2006. With the current economic and political situation in Zimbabwe improving, the drive by the Government to encourage independent power producers, the prospects for the development of small hydropower are promising....

Molded ultra-low density microcellular foams

International Nuclear Information System (INIS)

Rand, P.B.; Montoya, O.J.

1986-07-01

Ultra-low density (< 0.01 g/cc) microcellular foams were required for the NARYA pulsed-power-driven x-ray laser development program. Because of their extreme fragility, molded pieces would be necessary to successfully field these foams in the pulsed power accelerator. All of the foams evaluated were made by the thermally induced phase separation technique from solutions of water soluble polymers. The process involved rapidly freezing the solution to induce the phase separation, and then freeze drying to remove the water without destroying the foam's structure. More than sixty water soluble polymers were evaluated by attempting to make their solutions into foams. The foams were evaluated for shrinkage, density, and microstructure to determine their suitability for molding and meeting the required density and cell size requirements of 5.0 mg/cc and less than twenty μmeters. Several promising water soluble polymers were identified including the polyactylic acids, guar gums, polyactylamide, and polyethylene oxide. Because of thier purity, structure, and low shrinkage, the polyacrylic acids were chosen to develop molding processes. The initial requirements were for 2.0 cm. long molded rods with diameters of 1.0, 2.0. and 3.0 mm. These rods were made by freezing the solution in thin walled silicon rubber molds, extracting the frozen preform from the mold, and then freeze drying. Requirements for half rods and half annuli necessitated using aluminum molds. Again we successfully molded these shapes. Our best efforts to date involve molding annuli with 3.0 mm outside diameters and 2.0 mm inside diameters

Methane Ebullition in Temperate Hydropower Reservoirs and Implications for US Policy on Greenhouse Gas Emissions.

Science.gov (United States)

Miller, Benjamin L; Arntzen, Evan V; Goldman, Amy E; Richmond, Marshall C

2017-10-01

The United States is home to 2198 dams actively used for hydropower production. With the December 2015 consensus adoption of the United Nations Framework Convention on Climate Change Paris Agreement, it is important to accurately quantify anthropogenic greenhouse gas emissions. Methane ebullition, or methane bubbles originating from river or lake sediments, has been shown to account for nearly all methane emissions from tropical hydropower reservoirs to the atmosphere. However, distinct ebullitive methane fluxes have been studied in comparatively few temperate hydropower reservoirs globally. This study measures ebullitive and diffusive methane fluxes from two eastern Washington reservoirs, and synthesizes existing studies of methane ebullition in temperate, boreal, and tropical hydropower reservoirs. Ebullition comprises nearly all methane emissions (>97%) from this study's two eastern Washington hydropower reservoirs to the atmosphere. Summer methane ebullition from these reservoirs was higher than ebullition in six southeastern U.S. hydropower reservoirs, however it was similar to temperate reservoirs in other parts of the world. Our literature synthesis suggests that methane ebullition from temperate hydropower reservoirs can be seasonally elevated compared to tropical climates, however annual emissions are likely to be higher within tropical climates, emphasizing the possible range of methane ebullition fluxes and the need for the further study of temperate reservoirs. Possible future changes to the Intergovernmental Panel on Climate Change and UNFCCC guidelines for national greenhouse gas inventories highlights the need for accurate assessment of reservoir emissions.

Methane Ebullition in Temperate Hydropower Reservoirs and Implications for US Policy on Greenhouse Gas Emissions

Science.gov (United States)

Miller, Benjamin L.; Arntzen, Evan V.; Goldman, Amy E.; Richmond, Marshall C.

2017-10-01

The United States is home to 2198 dams actively used for hydropower production. With the December 2015 consensus adoption of the United Nations Framework Convention on Climate Change Paris Agreement, it is important to accurately quantify anthropogenic greenhouse gas emissions. Methane ebullition, or methane bubbles originating from river or lake sediments, has been shown to account for nearly all methane emissions from tropical hydropower reservoirs to the atmosphere. However, distinct ebullitive methane fluxes have been studied in comparatively few temperate hydropower reservoirs globally. This study measures ebullitive and diffusive methane fluxes from two eastern Washington reservoirs, and synthesizes existing studies of methane ebullition in temperate, boreal, and tropical hydropower reservoirs. Ebullition comprises nearly all methane emissions (>97%) from this study's two eastern Washington hydropower reservoirs to the atmosphere. Summer methane ebullition from these reservoirs was higher than ebullition in six southeastern U.S. hydropower reservoirs, however it was similar to temperate reservoirs in other parts of the world. Our literature synthesis suggests that methane ebullition from temperate hydropower reservoirs can be seasonally elevated compared to tropical climates, however annual emissions are likely to be higher within tropical climates, emphasizing the possible range of methane ebullition fluxes and the need for the further study of temperate reservoirs. Possible future changes to the Intergovernmental Panel on Climate Change and UNFCCC guidelines for national greenhouse gas inventories highlights the need for accurate assessment of reservoir emissions.

An ultra low noise AC beam transformer for deceleration and diagnostics of low intensity beams

CERN Document Server

González, C

1999-01-01

The design of a broad band ultra-low noise ferrite loaded AC beam transformer is presented. It is designed for use in the CERN Antiproton Decelerator (AD), where beams of a few 107 charges must be decelerated from 3.5 GeV/c to 100 MeV/c. It is used in the RF beam-phase loop, and for intensity and bunch shape measurements during deceleration. When the beam is debunched for cooling on magnetic flat tops, the pick-up is used for measurements of intensity and momentum distribution by means of longitudinal Schottky scans. When used as Schottky pick-up, the signal to noise ratio should be better by about 40 dB than the existing stripline based longitudinal Schottky pick-up. The integrated design of pick-up and associated low-noise amplifier is presented. The achieved noise performance of a few from 1 to 3 MHz is obtained by attaching a low-noise, high-impedance silicon JFET (junction field effect transistor) amplifier to a high-Q resonant ferrite loaded cavity, and then eliminating the resonant response by low-nois...

Low Cost Constant – Head Drip Irrigation Emitter for Climate ...

African Journals Online (AJOL)

Low Cost Constant – Head Drip Irrigation Emitter for Climate Change Adaptation in Nigeria: Engineering Design and Calibration. ... The drip system comprises of abarrel, sub-main line, lateral lines, tubes and emitters, it can irrigate140 crop ...

Ultra-low fertility in South Korea: The role of the tempo effect

Directory of Open Access Journals (Sweden)

Sam Hyun Yoo

2018-02-01

Full Text Available Background: The total fertility rate (TFR in South Korea has fallen below 1.3 since 2001. The role of the rapid shift toward a late-childbearing pattern in driving Korean fertility decline to this ultra-low level has been little explored until now. Objective: We provide an in-depth analysis of period fertility trends by birth order in South Korea from 1981 to 2015, when the period TFR fell from 2.57 to extremely low levels. Methods: We combine census and birth registration data to estimate period and cohort fertility indicators by birth order. We compare changes in conventional TFR with tempo- and parity-adjusted total fertility rate (TFRp* and their birth-order-specific components. Results: The tempo effect linked to the shift toward delayed childbearing has had a strong and persistent negative influence on period TFRs in South Korea since the early 1980s. Without the shift to later childbearing, period fertility rates in South Korea would consistently stay higher and decline more gradually, reaching a threshold of very low fertility, 1.5, only in 2014. The postponement of childbearing and the resulting tempo effect were strongest in the early 2000s, when Korean TFR reached the lowest levels. More recently, Korean fertility has been characterized by a diminishing tempo effect and falling first and second birth rates. This trend marks a break with the previous pattern of almost universal fertility and a strong two-child family model. Contribution: Our study demonstrates the importance of the tempo effect in explaining the shift to ultra-low fertility in South Korea and in East Asia

Impact of the hydropower installations on the environment as revealed in the environmental impact studies of the Institute of Hydroelectric Studies and Design

International Nuclear Information System (INIS)

Teodorescu, Dan

1996-01-01

The results of the studies of hydropower installation impact on the environment carried out by ISPH are presented. These studies are based on the recommendations of the UN Program for the Environment, as well as those of the European Community. In the period 1993-1995 more than 15 impact studies have been carried out taking into account aspects related to geology, geomorphology, seismology, hydrology, cultural-historical patrimony archaeology, tourism and aesthetics. Both high water fall and low water fall installations located at different altitudes have been analysed. Consequently, the construction of the dams were different. From the studies, three categories of problems can be reported: 1. specific problems of a certain hydropower installation; 2. specific problems of a certain type of hydropower installation; 3. general problems regardless of the power installation type. (author)