WorldWideScience

Sample records for zero-co2-emission high-efficiency power

  1. Thermoeconomic analysis of a novel zero-CO2-emission high-efficiency power cycle using LNG coldness

    International Nuclear Information System (INIS)

    Liu, Meng; Lior, Noam; Zhang, Na; Han, Wei

    2009-01-01

    This paper presents a thermoeconomic analysis aimed at the optimization of a novel zero-CO 2 and other emissions and high-efficiency power and refrigeration cogeneration system, COOLCEP-S (Patent pending), which uses the liquefied natural gas (LNG) coldness during its revaporization. It was predicted that at the turbine inlet temperature (TIT) of 900 C, the energy efficiency of the COOLCEP-S system reaches 59%. The thermoeconomic analysis determines the specific cost, the cost of electricity, the system payback period and the total net revenue. The optimization started by performing a thermodynamic sensitivity analysis, which has shown that for a fixed TIT and pressure ratio, the pinch point temperature difference in the recuperator, (delta)T p1 , and that in the condenser, (delta)T p2 are the most significant unconstrained variables to have a significant effect on the thermal performance of novel cycle. The payback period of this novel cycle (with fixed net power output of 20 MW and plant life of 40 years) was ∝5.9 years at most, and would be reduced to ∝3.1 years at most when there is a market for the refrigeration byproduct. The capital investment cost of the economically optimized plant is estimated to be about 1000 /kWe, and the cost of electricity is estimated to be 0.34-0.37 CNY/kWh (∝0.04 USD/kWh). These values are much lower than those of conventional coal power plants being installed at this time in China, which, in contrast to COOLCEP-S, do produce CO 2 emissions at that. (author)

  2. Eindhoven Airport : towards zero CO2 emissions

    NARCIS (Netherlands)

    Jorge Simoes Pedro, Joana

    2015-01-01

    Eindhoven airport is growing and it is strongly committed to take this opportunity to invest in innovative solutions for a sustainable development. Therefore, this document proposes a strategic plan for reaching Zero CO2 emissions at Eindhoven airport. This document proposes to reduce the CO2

  3. A novel polygeneration process to co-produce ethylene and electricity from shale gas with zero CO2 emissions via methane oxidative coupling

    International Nuclear Information System (INIS)

    Khojasteh Salkuyeh, Yaser; Adams, Thomas A.

    2015-01-01

    Highlights: • Development of an ethylene plant from shale gases with zero CO 2 emissions. • Oxidative coupling of methane is used for the conversion of gas to ethylene. • Polygeneration strategy is used to improve the profitability of plant. - Abstract: A techno-economic analysis of a novel process to co-produce ethylene and electricity using a recently developed methane oxidative coupling catalyst is presented. Several design variants are considered, featuring the use of traditional gas turbines, chemical looping combustion, and 100% carbon dioxide capture. Mass and energy balance simulations were carried out using Aspen Plus simulations, and particle swarm optimization was used to determine the optimal process design under a variety of market scenarios. A custom model for the gas turbine section was used to ensure that the negative impacts of various cooling strategies were factored into the analysis. The results show that by synergistically co-producing power and ethylene using this catalyst, ethylene can be produced at costs close to traditional steam cracking methods with nearly zero carbon dioxide emissions, even when factoring in the relatively poor conversion and selectivity of the chosen catalyst

  4. Integration of coal gasification and packed bed CLC for high efficiency and near-zero emission power generation

    NARCIS (Netherlands)

    Spallina, V.; Romano, M.C.; Chiesa, P.; Gallucci, F.; Sint Annaland, van M.; Lozza, G.

    2014-01-01

    A detailed thermodynamic analysis has been carried out of large-scale coal gasification-based power plant cycles with near zero CO2 emissions, integrated with chemical looping combustion (CLC). Syngas from coal gasification is oxidized in dynamically operated packed bed reactors (PBRs), generating a

  5. High-power, high-efficiency FELs

    International Nuclear Information System (INIS)

    Sessler, A.M.

    1989-04-01

    High power, high efficiency FELs require tapering, as the particles loose energy, so as to maintain resonance between the electromagnetic wave and the particles. They also require focusing of the particles (usually done with curved pole faces) and focusing of the electromagnetic wave (i.e. optical guiding). In addition, one must avoid transverse beam instabilities (primarily resistive wall) and longitudinal instabilities (i.e sidebands). 18 refs., 7 figs., 3 tabs

  6. High Efficiency Reversible Fuel Cell Power Converter

    DEFF Research Database (Denmark)

    Pittini, Riccardo

    as well as different dc-ac and dc-dc converter topologies are presented and analyzed. A new ac-dc topology for high efficiency data center applications is proposed and an efficiency characterization based on the fuel cell stack I-V characteristic curve is presented. The second part discusses the main...... converter components. Wide bandgap power semiconductors are introduced due to their superior performance in comparison to traditional silicon power devices. The analysis presents a study based on switching loss measurements performed on Si IGBTs, SiC JFETs, SiC MOSFETs and their respective gate drivers...

  7. High Efficiency Power Converter for Low Voltage High Power Applications

    DEFF Research Database (Denmark)

    Nymand, Morten

    The topic of this thesis is the design of high efficiency power electronic dc-to-dc converters for high-power, low-input-voltage to high-output-voltage applications. These converters are increasingly required for emerging sustainable energy systems such as fuel cell, battery or photo voltaic based...

  8. Series-Tuned High Efficiency RF-Power Amplifiers

    DEFF Research Database (Denmark)

    Vidkjær, Jens

    2008-01-01

    An approach to high efficiency RF-power amplifier design is presented. It addresses simultaneously efficiency optimization and peak voltage limitations when transistors are pushed towards their power limits.......An approach to high efficiency RF-power amplifier design is presented. It addresses simultaneously efficiency optimization and peak voltage limitations when transistors are pushed towards their power limits....

  9. High Efficiency Power Converter for Low Voltage High Power Applications

    DEFF Research Database (Denmark)

    Nymand, Morten

    The topic of this thesis is the design of high efficiency power electronic dc-to-dc converters for high-power, low-input-voltage to high-output-voltage applications. These converters are increasingly required for emerging sustainable energy systems such as fuel cell, battery or photo voltaic based......, and remote power generation for light towers, camper vans, boats, beacons, and buoys etc. A review of current state-of-the-art is presented. The best performing converters achieve moderately high peak efficiencies at high input voltage and medium power level. However, system dimensioning and cost are often...

  10. Fusion blankets for high efficiency power cycles

    International Nuclear Information System (INIS)

    Powell, J.R.; Fillo, J.A.; Horn, F.L.; Lazareth, O.W.; Usher, J.L.

    1980-04-01

    Definitions are given of 10 generic blanket types and the specific blanket chosen to be analyzed in detail from each of the 10 types. Dimensions, compositions, energy depositions and breeding ratios (where applicable) are presented for each of the 10 designs. Ultimately, based largely on neutronics and thermal hyraulics results, breeding an nonbreeding blanket options are selected for further design analysis and integration with a suitable power conversion subsystem

  11. High efficiency USC power plant - present status and future potential

    Energy Technology Data Exchange (ETDEWEB)

    Blum, R. [Faelleskemikerne I/S Fynsvaerket (Denmark); Hald, J. [Elsam/Elkraft/TU Denmark (Denmark)

    1998-12-31

    Increasing demand for energy production with low impact on the environment and minimised fuel consumption can be met with high efficient coal fired power plants with advanced steam parameters. An important key to this improvement is the development of high temperature materials with optimised mechanical strength. Based on the results of more than ten years of development a coal fired power plant with an efficiency above 50 % can now be realised. Future developments focus on materials which enable an efficiency of 52-55 %. (orig.) 25 refs.

  12. High efficiency USC power plant - present status and future potential

    Energy Technology Data Exchange (ETDEWEB)

    Blum, R [Faelleskemikerne I/S Fynsvaerket (Denmark); Hald, J [Elsam/Elkraft/TU Denmark (Denmark)

    1999-12-31

    Increasing demand for energy production with low impact on the environment and minimised fuel consumption can be met with high efficient coal fired power plants with advanced steam parameters. An important key to this improvement is the development of high temperature materials with optimised mechanical strength. Based on the results of more than ten years of development a coal fired power plant with an efficiency above 50 % can now be realised. Future developments focus on materials which enable an efficiency of 52-55 %. (orig.) 25 refs.

  13. High Power High Efficiency Diode Laser Stack for Processing

    Science.gov (United States)

    Gu, Yuanyuan; Lu, Hui; Fu, Yueming; Cui, Yan

    2018-03-01

    High-power diode lasers based on GaAs semiconductor bars are well established as reliable and highly efficient laser sources. As diode laser is simple in structure, small size, longer life expectancy with the advantages of low prices, it is widely used in the industry processing, such as heat treating, welding, hardening, cladding and so on. Respectively, diode laser could make it possible to establish the practical application because of rectangular beam patterns which are suitable to make fine bead with less power. At this power level, it can have many important applications, such as surgery, welding of polymers, soldering, coatings and surface treatment of metals. But there are some applications, which require much higher power and brightness, e.g. hardening, key hole welding, cutting and metal welding. In addition, High power diode lasers in the military field also have important applications. So all developed countries have attached great importance to high-power diode laser system and its applications. This is mainly due their low performance. In this paper we will introduce the structure and the principle of the high power diode stack.

  14. High efficiency heat transport and power conversion system for cascade

    International Nuclear Information System (INIS)

    Maya, I.; Bourque, R.F.; Creedon, R.L.; Schultz, K.R.

    1985-02-01

    The Cascade ICF reactor features a flowing blanket of solid BeO and LiAlO 2 granules with very high temperature capability (up to approx. 2300 K). The authors present here the design of a high temperature granule transport and heat exchange system, and two options for high efficiency power conversion. The centrifugal-throw transport system uses the peripheral speed imparted to the granules by the rotating chamber to effect granule transport and requires no additional equipment. The heat exchanger design is a vacuum heat transfer concept utilizing gravity-induced flow of the granules over ceramic heat exchange surfaces. A reference Brayton power cycle is presented which achieves 55% net efficiency with 1300 K peak helium temperature. A modified Field steam cycle (a hybrid Rankine/Brayton cycle) is presented as an alternate which achieves 56% net efficiency

  15. A High Efficiency PSOFC/ATS-Gas Turbine Power System

    Energy Technology Data Exchange (ETDEWEB)

    W.L. Lundberg; G.A. Israelson; M.D. Moeckel; S.E. Veyo; R.A. Holmes; P.R. Zafred; J.E. King; R.E. Kothmann

    2001-02-01

    A study is described in which the conceptual design of a hybrid power system integrating a pressurized Siemens Westinghouse solid oxide fuel cell generator and the Mercury{trademark} 50 gas turbine was developed. The Mercury{trademark} 50 was designed by Solar Turbines as part of the US. Department of Energy Advanced Turbine Systems program. The focus of the study was to develop the hybrid power system concept that principally would exhibit an attractively-low cost of electricity (COE). The inherently-high efficiency of the hybrid cycle contributes directly to achieving this objective, and by employing the efficient, power-intensive Mercury{trademark} 50, with its relatively-low installed cost, the higher-cost SOFC generator can be optimally sized such that the minimum-COE objective is achieved. The system cycle is described, major system components are specified, the system installed cost and COE are estimated, and the physical arrangement of the major system components is discussed. Estimates of system power output, efficiency, and emissions at the system design point are also presented. In addition, two bottoming cycle options are described, and estimates of their effects on overall-system performance, cost, and COE are provided.

  16. HIGH EFFICIENCY GENERATION OF HYDROGEN FUELS USING NUCLEAR POWER

    Energy Technology Data Exchange (ETDEWEB)

    BROWN,LC; BESENBRUCH,GE; LENTSCH,RD; SCHULTZ,KR; FUNK,JF; PICKARD,PS; MARSHALL,AC; SHOWALTER,SK

    2003-06-01

    OAK B202 HIGH EFFICIENCY GENERATION OF HYDROGEN FUELS USING NUCLEAR POWER. Combustion of fossil fuels, used to power transportation, generate electricity, heat homes and fuel industry provides 86% of the world's energy. Drawbacks to fossil fuel utilization include limited supply, pollution, and carbon dioxide emissions. Carbon dioxide emissions, thought to be responsible for global warming, are now the subject of international treaties. Together, these drawbacks argue for the replacement of fossil fuels with a less-polluting potentially renewable primary energy such as nuclear energy. Conventional nuclear plants readily generate electric power but fossil fuels are firmly entrenched in the transportation sector. Hydrogen is an environmentally attractive transportation fuel that has the potential to displace fossil fuels. Hydrogen will be particularly advantageous when coupled with fuel cells. Fuel cells have higher efficiency than conventional battery/internal combustion engine combinations and do not produce nitrogen oxides during low-temperature operation. Contemporary hydrogen production is primarily based on fossil fuels and most specifically on natural gas. When hydrogen is produced using energy derived from fossil fuels, there is little or no environmental advantage. There is currently no large scale, cost-effective, environmentally attractive hydrogen production process available for commercialization, nor has such a process been identified. The objective of this work is to find an economically feasible process for the production of hydrogen, by nuclear means, using an advanced high-temperature nuclear reactor as the primary energy source. Hydrogen production by thermochemical water-splitting (Appendix A), a chemical process that accomplishes the decomposition of water into hydrogen and oxygen using only heat or, in the case of a hybrid thermochemical process, by a combination of heat and electrolysis, could meet these goals. Hydrogen produced from

  17. High efficiency power production from biomass and waste

    Energy Technology Data Exchange (ETDEWEB)

    Rabou, L.P.L.M.; Van Leijenhorst, R.J.C.; Hazewinkel, J.H.O. [ECN Biomass, Coal and Environment, Petten (Netherlands)

    2008-11-15

    Two-stage gasification allows power production from biomass and waste with high efficiency. The process involves pyrolysis at about 550C followed by heating of the pyrolysis gas to about 1300C in order to crack hydrocarbons and obtain syngas, a mixture of H2, CO, H2O and CO2. The second stage produces soot as unwanted by-product. Experimental results are reported on the suppression of soot formation in the second stage for two different fuels: beech wood pellets and Rofire pellets, made from rejects of paper recycling. Syngas obtained from these two fuels and from an industrial waste fuel has been cleaned and fed to a commercial SOFC stack for 250 hours in total. The SOFC stack showed comparable performance on real and synthetic syngas and no signs of accelerated degradation in performance over these tests. The experimental results have been used for the design and analysis of a future 25 MWth demonstration plant. As an alternative, a 2.6 MWth system was considered which uses the Green MoDem approach to convert waste fuel into bio-oil and syngas. The 25 MWth system can reach high efficiency only if char produced in the pyrolysis step is converted into additional syngas by steam gasification, and if SOFC off-gas and system waste heat are used in a steam bottoming cycle for additional power production. A net electrical efficiency of 38% is predicted. In addition, heat can be delivered with 37% efficiency. The 2.6 MWth system with only a dual fuel engine to burn bio-oil and syngas promises nearly 40% electrical efficiency plus 41% efficiency for heat production. If syngas is fed to an SOFC system and off-gas and bio-oil to a dual fuel engine, the electrical efficiency can rise to 45%. However, the efficiency for heat production drops to 15%, as waste heat from the SOFC system cannot be used effectively. The economic analysis makes clear that at -20 euro/tonne fuel, 70 euro/MWh for electricity and 7 euro/GJ for heat the 25 MWth system is not economically viable at the

  18. Development of the ultra high efficiency thermal power generation facility

    Energy Technology Data Exchange (ETDEWEB)

    Sano, Toshihiro

    2010-09-15

    In order to prevent global warming, attention is focused on nuclear power generation and renewable energy such as wind and solar power generation. The electric power suppliers of Japan are aiming to increase the amount of nuclear and non-fossil fuel power generation over 50% of the total power generation by 2020. But this means that the remaining half will still be of thermal power generation using fossil fuel and will still play an important role. Under such circumstances, further efficiency improvement of the thermal power generation and its aggressive implementation is ongoing in Japan.

  19. Cascade: a high-efficiency ICF power reactor

    International Nuclear Information System (INIS)

    Pitts, J.H.

    1985-01-01

    Cascade attains a net power-plant efficiency of 49% and its cost is competitive with high-temperature gas-cooled reactor, pressurized-water reactor, and coal-fired power plants. The Cascade reactor and blanket are made of ceramic materials and activation is 6 times less than that of the MARS Tandem Mirror Reactor operating at comparable power. Hands-on maintenance of the heat exchangers is possible one day after shutdown. Essentially all tritium is recovered in the vacuum system, with the remainder recovered from the helium power conversion loop. Tritium leakage external to the vacuum system and power conversion loop is only 0.03 Ci/d

  20. Designing High Efficient Solar Powered OLED Lighting Systems

    DEFF Research Database (Denmark)

    Ploug, Rasmus Overgaard; Poulsen, Peter Behrensdorff; Thorsteinsson, Sune

    2016-01-01

    for the 10 Wp version. Furthermore, we present measurements of state-of-the-art commercial available OLED with regards to the luminous flux, luminous efficacy, luminance homogeneity, temperature dependency and IV characteristic of the OLED panels. In addition, solar powered OLED product concepts are proposed.......OLEDs used in solar powered lighting applications is a market of the future. This paper reports the development of electronic Three-Port-Converters for PV OLED product integration in the low-power area respectively for 1-10 Wp and 10-50 Wp with a peak efficiency of 97% at 1.8 W of PV power...

  1. PSO 7171 - Oxyfuel Combustion for below zero CO2 emissions

    DEFF Research Database (Denmark)

    Toftegaard, Maja Bøg; Brix, Jacob; Hansen, Brian Brun

    for the continuous utilisation of the existing energy producing system in the transformation period. Oxyfuel combustion is one of the possible CCS technologies which show promising perspectives for implementation in industrial scale within a relatively short period of time. Oxyfuel combustion deviates from...

  2. High-efficiency thermionic power generator, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Planetary missions (e.g., Pioneer, Cassini, or Voyager) and applications with moderate power draw and increased mobility requirements (e.g., Curiosity) have...

  3. MMIC for High-Efficiency Ka-BAnd GaN Power Amplifiers (2007043), Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — This proposal addresses the need for high-efficiency, high-output power amplifiers operating in the Ka-band frequencies. For space communications, the power...

  4. High Efficiency, High Temperature Foam Core Heat Exchanger for Fission Surface Power Systems, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Fission-based power systems with power levels of 30 to ≥100 kWe will be needed for planetary surface bases. Development of high temperature, high efficiency heat...

  5. High quality, high efficiency welding technology for nuclear power plants

    International Nuclear Information System (INIS)

    Aoki, Shigeyuki; Nagura, Yasumi

    1996-01-01

    For nuclear power plants, it is required to ensure the safety under the high reliability and to attain the high rate of operation. In the manufacture and installation of the machinery and equipment, the welding techniques which become the basis exert large influence to them. For the purpose of improving joint performance and excluding human errors, welding heat input and the number of passes have been reduced, the automation of welding has been advanced, and at present, narrow gap arc welding and high energy density welding such as electron beam welding and laser welding have been put to practical use. Also in the welding of pipings, automatic gas metal arc welding is employed. As for the welding of main machinery and equipment, there are the welding of the joints that constitute pressure boundaries, the build-up welding on the internal surfaces of pressure vessels for separating primary water from them, and the sealing welding of heating tubes and tube plates in steam generators. These weldings are explained. The welding of pipings and the state of development and application of new welding methods are reported. (K.I.)

  6. Prospects for development of powerful, highly efficient, relativistic gyrodevices

    International Nuclear Information System (INIS)

    Nusinovich, G.S.; Granatstein, V.L.

    1992-01-01

    For various applications the required parameters of sources of powerful microwave radiation lie far beyond the capabilities of existing tubes. This provokes an interest in reconsidering basic principles of relevant microwave sources in order to search for alternative concepts in their development. One of the most promising devices in the short-wavelength region of microwaves is the cyclotron resonance maser (CRM). During the last decade, two important varieties of CRMs have been distinguished, namely, gyrotrons, which operate at frequencies close to cut-off, and cyclotron autoresonance masers (CARMs), which operate at frequencies far from cut-off. When the axial phase velocity of the wave in properly adjusted to the beam voltage and electron pitch-ratio, the efficiency of relativistic CRMs may be high (≥50%). The method of optimizing efficiency based on a partial compensation of the shift in the relativistic electron cyclotron frequency by the change in the Doppler term can be, in principle, accompanied by a corresponding profiling of the external magnetic field and/or the wave phase velocity in a slightly irregular waveguide. These methods can be used in such relativistic CRMs as relativistic gyrotrons, gyroklystrons, gyro-traveling-wave-tubes and gyrotwistrons. The most important point is their sensitivity to a spread in electron parameters. As the beam voltage grows, the operation becomes more sensitive. However, at relatively low voltages such devices are quite tolerant to electron velocity spread

  7. High efficiency combined heat and power facilities - benefits and barriers

    International Nuclear Information System (INIS)

    Klein, M.

    2001-01-01

    There are important linkages between the economy, energy production, the environment and our health. Where thermal energy is needed, distributed Combined Heat and Power facilities, using gas turbines, reciprocating engines and future fuel cells can provide significant improvements to our long term mix of energy production. Local generation can also have benefits in security of energy supply and economic savings. This paper is intended to discuss the relevant air pollution and greenhouse gas emissions from modem CHP plants, the emission prevention and reduction methods available, and their operating experience and cost-effectiveness. Mention is made of recently constructed industrial and commercial plants, and institutional barriers to further development. Solutions described for these barriers include the need for more awareness of opportunities, improved access to the electricity grid, the proper design balance between thermal and electric for CHP systems rather than large combined cycles, improved corporate taxation incentives, and the assessment of all environmental and economic benefits when considering such cleaner sources in a restructured energy market. (author)

  8. Performance of a high efficiency high power UHF klystron

    International Nuclear Information System (INIS)

    Konrad, G.T.

    1977-03-01

    A 500 kW c-w klystron was designed for the PEP storage ring at SLAC. The tube operates at 353.2 MHz, 62 kV, a microperveance of 0.75, and a gain of approximately 50 dB. Stable operation is required for a VSWR as high as 2 : 1 at any phase angle. The design efficiency is 70%. To obtain this value of efficiency, a second harmonic cavity is used in order to produce a very tightly bunched beam in the output gap. At the present time it is planned to install 12 such klystrons in PEP. A tube with a reduced size collector was operated at 4% duty at 500 kW. An efficiency of 63% was observed. The same tube was operated up to 200 kW c-w for PEP accelerator cavity tests. A full-scale c-w tube reached 500 kW at 65 kV with an efficiency of 55%. In addition to power and phase measurements into a matched load, some data at various load mismatches are presented

  9. High voltage generator circuit with low power and high efficiency applied in EEPROM

    International Nuclear Information System (INIS)

    Liu Yan; Zhang Shilin; Zhao Yiqiang

    2012-01-01

    This paper presents a low power and high efficiency high voltage generator circuit embedded in electrically erasable programmable read-only memory (EEPROM). The low power is minimized by a capacitance divider circuit and a regulator circuit using the controlling clock switch technique. The high efficiency is dependent on the zero threshold voltage (V th ) MOSFET and the charge transfer switch (CTS) charge pump. The proposed high voltage generator circuit has been implemented in a 0.35 μm EEPROM CMOS process. Measured results show that the proposed high voltage generator circuit has a low power consumption of about 150.48 μW and a higher pumping efficiency (83.3%) than previously reported circuits. This high voltage generator circuit can also be widely used in low-power flash devices due to its high efficiency and low power dissipation. (semiconductor integrated circuits)

  10. Generating power at high efficiency combined cycle technology for sustainable energy production

    CERN Document Server

    Jeffs, E

    2008-01-01

    Combined cycle technology is used to generate power at one of the highest levels of efficiency of conventional power plants. It does this through primary generation from a gas turbine coupled with secondary generation from a steam turbine powered by primary exhaust heat. Generating power at high efficiency thoroughly charts the development and implementation of this technology in power plants and looks to the future of the technology, noting the advantages of the most important technical features - including gas turbines, steam generator, combined heat and power and integrated gasification com

  11. Research & Implementation of AC - DC Converter with High Power Factor & High Efficiency

    Directory of Open Access Journals (Sweden)

    Hsiou-Hsian Nien

    2014-05-01

    Full Text Available In this paper, we design and develop a high power factor, high efficiency two-stage AC - DC power converter. This paper proposes a two-stage AC - DC power converter. The first stage is boost active power factor correction circuit. The latter stage is near constant frequency LLC resonant converter. In addition to traditional LLC high efficiency advantages, light-load conversion efficiency of this power converter can be improved. And it possesses high power factor and near constant frequency operating characteristics, can significantly reduce the electromagnetic interference. This paper first discusses the main structure and control manner of power factor correction circuit. And then by the LLC resonant converter equivalent model proceed to circuit analysis to determine the important parameters of the converter circuit elements. Then design a variable frequency resonant tank. The resonant frequency can change automatically on the basis of the load to reach near constant frequency operation and a purpose of high efficiency. Finally, actually design and produce an AC – DC power converter with output of 190W to verify the characteristics and feasibility of this converter. The experimental results show that in a very light load (9.5 W the efficiency is as high as 81%, the highest efficiency of 88% (90 W. Full load efficiency is 87%. At 19 W ~ 190 W power changes, the operating frequency change is only 0.4 kHz (AC 110 V and 0.3 kHz (AC 220 V.

  12. High efficiency three-phase power factor correction rectifier using SiC switches

    DEFF Research Database (Denmark)

    Kouchaki, Alireza; Nymand, Morten

    2017-01-01

    This paper presents designing procedure of a high efficiency 5 kW silicon-carbide (SiC) based threephase power factor correction (PFC). SiC switches present low capacitive switching loss compared to the alternative Si switches. Therefore, the switching frequency can be increased and hence the siz...

  13. A broadband high-efficiency Doherty power amplifier using symmetrical devices

    Science.gov (United States)

    Cheng, Zhiqun; Zhang, Ming; Li, Jiangzhou; Liu, Guohua

    2018-04-01

    This paper proposes a method for broadband and high-efficiency amplification of Doherty power amplifier (DPA) using symmetric devices. In order to achieve the perfect load modulation, the carrier amplifier output circuit total power length is designed to odd multiple of 90°, and the peak amplifier output total power length is designed to even multiple of 180°. The proposed method is demonstrated by designing a broadband high-efficiency DPA using identical 10-W packaged GaN HEMT devices. Measurement results show that over 51% drain efficiency is achieved at 6-dB back-off power, over the frequency band of 1.9–2.4 GHz. Project supported by the National Natural Science Foundation of China (No. 60123456), the Zhejiang Provincial Natural Science Foundation of China (No. LZ16F010001), and the Zhejiang Provincial Public Technology Research Project (No. 2016C31070).

  14. Analysis of Valve Requirements for High-Efficiency Digital Displacement Fluid Power Motors

    DEFF Research Database (Denmark)

    Rømer, Daniel; Johansen, Per; Pedersen, Henrik C.

    2013-01-01

    Digital displacement fluid power motors have been shown to enable high-efficiency operation in a wide operation range, including the part load range where conventional fluid power motors suffers from poor efficiencies. The use of these digital displacement motors set new requirements for the valve...... transition time and flow-pressure coefficient are normalized, leading to a presentation of the general efficiency map of the digital displacement motor. Finally the performance of existing commercial valves with respect to digital motors is commented....

  15. High Efficiency Power Converter for a Doubly-fed SOEC/SOFC System

    DEFF Research Database (Denmark)

    Tomas Manez, Kevin; Anthon, Alexander; Zhang, Zhe

    2016-01-01

    Regenerative fuel cells (RFC) have become an attractive technology for energy storage systems due to their high energy density and lower end-of-life disposal concerns. However, high efficiency design of power conditioning unit (PCU) for RFC becomes challenging due to their asymmetrical currentpow...... operating range of the RFC as well as the utilization of the same control strategy design for the two RFC operating modes....

  16. High Efficiency Three-phase Power Factor Correction Rectifier using Wide Band-Gap Devices

    DEFF Research Database (Denmark)

    Kouchaki, Alireza

    Improving the conversion efficiency of power factor correction (PFC) rectifiers has become compelling due to their wide applications such as adjustable speed drives, uninterruptible power supplies (UPS), and battery chargers for electric vehicles (EVs). The attention to PFCs has increased even more....... Therefore, current controllers are also important to be investigated in this project. In this PhD research work, a comprehensive design of a two-level three-phase PFC rectifier using silicon-carbide (SiC) switches to achieve high efficiency is presented. The work is divided into two main parts: 1) Optimum...

  17. High efficiency and long life of a three-phase power conditioner via interleave control

    Directory of Open Access Journals (Sweden)

    Kenji Amei

    2016-01-01

    Full Text Available This study describes the high efficiency and long life of three-phase power conditioners of a photovoltaic (PV system. The current PV system, which is widely spread, has two problems. The first problem is the lifetime of a power conditioner, whereas the other problem is the drop in the efficiency of the conversion because of the characteristics of the solar cell. For those problems, the solar panel and boost chopper circuit were divided into a plurality to configure a power conditioner, and an electrolytic capacitor-less driver with interleave control was realized. The drop in the current generated by the solar cell was suppressed, and an improvement in power generation efficiency was expected. The configuration and principle of a proposed circuit were explained, and results of simulation and experiment were reported.

  18. Volume Bragg grating narrowed high-power and highly efficient cladding-pumped Raman fiber laser.

    Science.gov (United States)

    Liu, Jun; Yao, Weichao; Zhao, Chujun; Shen, Deyuan; Fan, Dianyuan

    2014-12-10

    High-power and highly efficient operation of a single-mode cladding-pumped Raman fiber laser with narrow lasing bandwidth is demonstrated. The spectral narrowing was realized by an external cavity containing a volume Bragg grating with a center wavelength of 1658 nm. A maximum output power of 10.4 W at 1658.3 nm with a spectral linewidth (FWHM) of ∼0.1  nm was obtained for the launched pump power of 18.4 W, corresponding to a slope efficiency of 109% with respect to the launched pump power. Lasing characteristics of free-running operation are also evaluated and discussed.

  19. High efficiency class-I audio power amplifier using a single adaptive supply

    International Nuclear Information System (INIS)

    Peng Zhenfei; Yang Shanshand; Feng Yong; Hong Zhiliang; Liu Yang

    2012-01-01

    A high efficiency class-I linear audio power amplifier (PA) with an adaptive supply is presented. Its efficiency is improved by a dynamic supply to reduce the power transistors' voltage drop. A gain compression technique is adopted to make the amplifier accommodate a single positive supply. Circuit complicity and chip area are reduced because no charge pump is necessary for the negative supply. A common shared mode voltage and a symmetric layout pattern are used to minimize the non-linearity. A peak efficiency of 80% is reached at peak output power. The measured THD+N before and after the supply switching point are 0.01% and 0.05%, respectively. The maximum output power is 410 mW for an 8 Ω speaker load. Unlike switching amplifiers, the class-I amplifier operates as a linear amplifier and hence has a low EMI. The advantage of a high efficiency and low EMI makes the class-I amplifier suitable for portable and RF sensitive applications. (semiconductor integrated circuits)

  20. Innovative-Simplified Nuclear Power Plant Efficiency Evaluation with High-Efficiency Steam Injector System

    International Nuclear Information System (INIS)

    Shoji, Goto; Shuichi, Ohmori; Michitsugu, Mori

    2006-01-01

    It is possible to establish simplified system with reduced space and total equipment weight using high-efficiency Steam Injectors (SI) instead of low-pressure feedwater heaters in Nuclear Power Plant (NPP). The SI works as a heat exchanger through direct contact between feedwater from condensers and extracted steam from turbines. It can get higher pressure than supplied steam pressure. The maintenance and reliability are still higher than the feedwater ones because SI has no movable parts. This paper describes the analysis of the heat balance, plant efficiency and the operation of this Innovative-Simplified NPP with high-efficiency SI. The plant efficiency and operation are compared with the electric power of 1100 MWe-class BWR system and the Innovative-Simplified BWR system with SI. The SI model is adapted into the heat balance simulator with a simplified model. The results show that plant efficiencies of the Innovated-Simplified BWR system are almost equal to original BWR ones. The present research is one of the projects that are carried out by Tokyo Electric Power Company, Toshiba Corporation, and six Universities in Japan, funded from the Institute of Applied Energy (IAE) of Japan as the national public research-funded program. (authors)

  1. Very High Efficiency Reactor (VHER) Concepts for Electrical Power Generation and Hydrogen Production

    International Nuclear Information System (INIS)

    PARMA JR, EDWARD J.; PICKARD, PAUL S.; SUO-ANTTILA, AHTI JORMA

    2003-01-01

    The goal of the Very High Efficiency Reactor study was to develop and analyze concepts for the next generation of nuclear power reactors. The next generation power reactor should be cost effective compared to current power generation plant, passively safe, and proliferation-resistant. High-temperature reactor systems allow higher electrical generating efficiencies and high-temperature process heat applications, such as thermo-chemical hydrogen production. The study focused on three concepts; one using molten salt coolant with a prismatic fuel-element geometry, the other two using high-pressure helium coolant with a prismatic fuel-element geometry and a fuel-pebble element design. Peak operating temperatures, passive-safety, decay heat removal, criticality, burnup, reactivity coefficients, and material issues were analyzed to determine the technical feasibility of each concept

  2. A novel power source for high-precision, highly efficient micro w-EDM

    International Nuclear Information System (INIS)

    Chen, Shun-Tong; Chen, Chi-Hung

    2015-01-01

    The study presents the development of a novel power source for high-precision, highly efficient machining of micropart microstructures using micro wire electrical discharge machining (w-EDM). A novel power source based on a pluri resistance–capacitance (pRC) circuit that can generate a high-frequency, high-peak current with a short pulse train is proposed and designed to enhance the performance of micro w-EDM processes. Switching between transistors is precisely controlled in the designed power source to create a high-frequency short-pulse train current. Various microslot cutting tests in both aluminum and copper alloys are conducted. Experimental results demonstrate that the pRC power source creates instant spark erosion resulting in markedly less material for removal, diminishing discharge crater size, and consequently an improved surface finish. A new evaluation approach for spark erosion ability (SEA) to assess the merits of micro EDM power sources is also proposed. In addition to increasing the speed of micro w-EDM by increasing wire feed rates by 1.6 times the original feed rate, the power source is more appropriate for machining micropart microstructures since there is less thermal breaking. Satisfactory cutting of an elaborate miniature hook-shaped structure and a high-aspect ratio microstructure with a squared-pillar array also reveal that the developed pRC power source is effective, and should be very useful in the manufacture of intricate microparts. (paper)

  3. Technology Roadmap: High-Efficiency, Low-Emissions Coal-Fired Power Generation

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-07-01

    Coal is the largest source of power globally and, given its wide availability and relatively low cost, it is likely to remain so for the foreseeable future. The High-Efficiency, Low-Emissions Coal-Fired Power Generation Roadmap describes the steps necessary to adopt and further develop technologies to improve the efficiency of the global fleet of coal. To generate the same amount of electricity, a more efficient coal-fired unit will burn less fuel, emit less carbon, release less local air pollutants, consume less water and have a smaller footprint. High-efficiency, low emissions (HELE) technologies in operation already reach a thermal efficiency of 45%, and technologies in development promise even higher values. This compares with a global average efficiency for today’s fleet of coal-fired plants of 33%, where three-quarters of operating units use less efficient technologies and more than half is over 25 years old. A successful outcome to ongoing RD&D could see units with efficiencies approaching 50% or even higher demonstrated within the next decade. Generation from older, less efficient technology must gradually be phased out. Technologies exist to make coal-fired power generation much more effective and cleaner burning. Of course, while increased efficiency has a major role to play in reducing emissions, particularly over the next 10 years, carbon capture and storage (CCS) will be essential in the longer term to make the deep cuts in carbon emissions required for a low-carbon future. Combined with CCS, HELE technologies can cut CO2 emissions from coal-fired power generation plants by as much as 90%, to less than 100 grams per kilowatt-hour. HELE technologies will be an influential factor in the deployment of CCS. For the same power output, a higher efficiency coal plant will require less CO2 to be captured; this means a smaller, less costly capture plant; lower operating costs; and less CO2 to be transported and stored.

  4. A high efficiency PWM CMOS class-D audio power amplifier

    Energy Technology Data Exchange (ETDEWEB)

    Zhu Zhangming; Liu Lianxi; Yang Yintang [Institute of Microelectronics, Xidian University, Xi' an 710071 (China); Lei Han, E-mail: zmyh@263.ne [Xi' an Power-Rail Micro Co., Ltd, Xi' an 710075 (China)

    2009-02-15

    Based on the difference close-loop feedback technique and the difference pre-amp, a high efficiency PWM CMOS class-D audio power amplifier is proposed. A rail-to-rail PWM comparator with window function has been embedded in the class-D audio power amplifier. Design results based on the CSMC 0.5 mum CMOS process show that the max efficiency is 90%, the PSRR is -75 dB, the power supply voltage range is 2.5-5.5 V, the THD+N in 1 kHz input frequency is less than 0.20%, the quiescent current in no load is 2.8 mA, and the shutdown current is 0.5 muA. The active area of the class-D audio power amplifier is about 1.47 x 1.52 mm{sup 2}. With the good performance, the class-D audio power amplifier can be applied to several audio power systems.

  5. A high efficiency PWM CMOS class-D audio power amplifier

    International Nuclear Information System (INIS)

    Zhu Zhangming; Liu Lianxi; Yang Yintang; Lei Han

    2009-01-01

    Based on the difference close-loop feedback technique and the difference pre-amp, a high efficiency PWM CMOS class-D audio power amplifier is proposed. A rail-to-rail PWM comparator with window function has been embedded in the class-D audio power amplifier. Design results based on the CSMC 0.5 μm CMOS process show that the max efficiency is 90%, the PSRR is -75 dB, the power supply voltage range is 2.5-5.5 V, the THD+N in 1 kHz input frequency is less than 0.20%, the quiescent current in no load is 2.8 mA, and the shutdown current is 0.5 μA. The active area of the class-D audio power amplifier is about 1.47 x 1.52 mm 2 . With the good performance, the class-D audio power amplifier can be applied to several audio power systems.

  6. A high efficiency PWM CMOS class-D audio power amplifier

    Science.gov (United States)

    Zhangming, Zhu; Lianxi, Liu; Yintang, Yang; Han, Lei

    2009-02-01

    Based on the difference close-loop feedback technique and the difference pre-amp, a high efficiency PWM CMOS class-D audio power amplifier is proposed. A rail-to-rail PWM comparator with window function has been embedded in the class-D audio power amplifier. Design results based on the CSMC 0.5 μm CMOS process show that the max efficiency is 90%, the PSRR is -75 dB, the power supply voltage range is 2.5-5.5 V, the THD+N in 1 kHz input frequency is less than 0.20%, the quiescent current in no load is 2.8 mA, and the shutdown current is 0.5 μA. The active area of the class-D audio power amplifier is about 1.47 × 1.52 mm2. With the good performance, the class-D audio power amplifier can be applied to several audio power systems.

  7. A 380 V High Efficiency and High Power Density Switched-Capacitor Power Converter using Wide Band Gap Semiconductors

    DEFF Research Database (Denmark)

    Fan, Lin; Knott, Arnold; Jørgensen, Ivan Harald Holger

    2018-01-01

    . This paper presents such a high voltage low power switched-capacitor DC-DC converter with an input voltage upto 380 V (compatible with rectified European mains) and an output power experimentally validated up to 21.3 W. The wideband gap semiconductor devices of GaN switches and SiC diodes are combined...... to compose the proposed power stage. Their switching and loss characteristics are analyzed with transient waveforms and thermal images. Different isolated driving circuits are compared and a compact isolated halfbridge driving circuit is proposed. The full-load efficiencies of 98.3% and 97.6% are achieved......State-of-the-art switched-capacitor DC-DC power converters mainly focus on low voltage and/or high power applications. However, at high voltage and low power levels, new designs are anticipated to emerge and a power converter that has both high efficiency and high power density is highly desirable...

  8. Design of The High Efficiency Power Factor Correction Circuit for Power Supply

    Directory of Open Access Journals (Sweden)

    Atiye Hülya OBDAN

    2017-12-01

    Full Text Available Designing power factor correction circuits for switched power supplies has become important in recent years in terms of efficient use of energy. Power factor correction techniques play a significant role in high power density and energy efficiency. For these purposes, bridgeless PFC topologies and control strategies have been developed alongside basic boost PFC circuits. The power density can be increased using bridgeless structures by means of reducing losses in the circuit. This article examines bridgeless PFC structures and compares their performances in terms of losses and power factor. A semi-bridgeless PFC, which is widely used at high power levels, was analyzed and simulated. The designed circuit simulation using the current mode control method was performed in the PSIM program. A prototype of a 900 W semi-bridgeless PFC circuit was implemented and the results obtained from the circuit are presented

  9. High-Efficiency, Ka-Band Solid-State Power Amplifier Utilizing GaN Technology, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — QuinStar Technology proposes to develop a high-efficiency, solid-state power amplifier (SSPA), operating at Ka-band frequencies, for high data rate, long range space...

  10. Silicon-Carbide Power MOSFET Performance in High Efficiency Boost Power Processing Unit for Extreme Environments

    Science.gov (United States)

    Ikpe, Stanley A.; Lauenstein, Jean-Marie; Carr, Gregory A.; Hunter, Don; Ludwig, Lawrence L.; Wood, William; Del Castillo, Linda Y.; Fitzpatrick, Fred; Chen, Yuan

    2016-01-01

    Silicon-Carbide device technology has generated much interest in recent years. With superior thermal performance, power ratings and potential switching frequencies over its Silicon counterpart, Silicon-Carbide offers a greater possibility for high powered switching applications in extreme environment. In particular, Silicon-Carbide Metal-Oxide- Semiconductor Field-Effect Transistors' (MOSFETs) maturing process technology has produced a plethora of commercially available power dense, low on-state resistance devices capable of switching at high frequencies. A novel hard-switched power processing unit (PPU) is implemented utilizing Silicon-Carbide power devices. Accelerated life data is captured and assessed in conjunction with a damage accumulation model of gate oxide and drain-source junction lifetime to evaluate potential system performance at high temperature environments.

  11. High efficiency-large capacity circulating water pump for Hamaoka Nuclear Power Station unit No.3

    International Nuclear Information System (INIS)

    Ito, Akihiko; Sasamuro, Takemi; Takeda, Hirohisa.

    1988-01-01

    No.3 plant in the Hamaoka Nuclear Power Station, Chube Electric Power Co., Inc. is the latest plant of 1100 MW class BWR type, which began the commercial operation in August, 1987. The seawater intake and discharge system of this plant is composed of the channel exceeding 2 km in the total length from the intake tower to the discharge port. The circulating water pump installed in this system has the capacity of 1620 m 3 /min and the total head of 16.5 m, which are the largest in the world. It attained the efficiency as high as more than 90%. Three pumps supply seawater to three-body condensers. The design of the impeller and the casing for obtaining high efficiency, the structural design for facilitating maintenance, the manufacture of a model pump and the performance test using it and so on are reported. The most important item in the manufacture was the form of the onebody impeller weighing 4.5t. The confirmation of the performance of the actual machines was carried out as a part of the synthetic function confirmation test at the power station, and the flow rate was measured with Pitot tubes and ultrasonic flowmeters. (Kako, I.)

  12. Powerful highly efficient KrF lamps excited by surface and barrier discharges

    International Nuclear Information System (INIS)

    Borisov, V M; Vodchits, V A; El'tsov, A V; Khristoforov, O B

    1998-01-01

    An investigation was made of the characteristics of KrF lamps with different types of excitation by surface and barrier discharges in which the dielectric material was sapphire. The conditions were determined for the attainment of an extremely high yield of the KrF* fluorescence with the internal efficiency η in ∼30 % and 22% for pulsed surface and barrier discharges, respectively. A homogeneous surface discharge was maintained without gas circulation when the pulse repetition rate was 5 x 10 4 Hz. Quasicontinuous excitation of a surface discharge at near-atmospheric pressure made it possible to reach a KrF* fluorescence power density of about 80 W cm -3 , which was close to the limit set by the kinetics of the gaseous medium. Under prolonged excitation conditions the intensity of the UV output radiation was limited by the permissible heating of the gas to a temperature above which the operating life of the gaseous mixture containing fluorine fell steeply. This was the reason for the advantage of surface over barrier discharges: the former were characterised by a high thermal conductivity of a thin (∼0.2 mm) plasma layer on the surface of the cooled dielectric, which made it possible to construct powerful highly efficient KrF and ArF lamps emitting UV radiation of up to 1 W cm -2 intensity. (laser system components)

  13. High efficiency fourth-harmonic generation from nanosecond fiber master oscillator power amplifier

    Science.gov (United States)

    Mu, Xiaodong; Steinvurzel, Paul; Rose, Todd S.; Lotshaw, William T.; Beck, Steven M.; Clemmons, James H.

    2016-03-01

    We demonstrate high power, deep ultraviolet (DUV) conversion to 266 nm through frequency quadrupling of a nanosecond pulse width 1064 nm fiber master oscillator power amplifier (MOPA). The MOPA system uses an Yb-doped double-clad polarization-maintaining large mode area tapered fiber as the final gain stage to generate 0.5-mJ, 10 W, 1.7- ns single mode pulses at a repetition rate of 20 kHz with measured spectral bandwidth of 10.6 GHz (40 pm), and beam qualities of Mx 2=1.07 and My 2=1.03, respectively. Using LBO and BBO crystals for the second-harmonic generation (SHG) and fourth-harmonic generation (FHG), we have achieved 375 μJ (7.5 W) and 92.5 μJ (1.85 W) at wavelengths of 532 nm and 266 nm, respectively. To the best of our knowledge these are the highest narrowband infrared, green and UV pulse energies obtained to date from a fully spliced fiber amplifier. We also demonstrate high efficiency SHG and FHG with walk-off compensated (WOC) crystal pairs and tightly focused pump beam. An SHG efficiency of 75%, FHG efficiency of 47%, and an overall efficiency of 35% from 1064 nm to 266 nm are obtained.

  14. Improvement of force factor of magnetostrictive vibration power generator for high efficiency

    International Nuclear Information System (INIS)

    Kita, Shota; Ueno, Toshiyuki; Yamada, Sotoshi

    2015-01-01

    We develop high power magnetostrictive vibration power generator for battery-free wireless electronics. The generator is based on a cantilever of parallel beam structure consisting of coil-wound Galfenol and stainless plates with permanent magnet for bias. Oscillating force exerted on the tip bends the cantilever in vibration yields stress variation of Galfenol plate, which causes flux variation and generates voltage on coil due to the law of induction. This generator has advantages over conventional, such as piezoelectric or moving magnet types, in the point of high efficiency, highly robust, and low electrical impedance. Our concern is the improvement of energy conversion efficiency dependent on the dimension. Especially, force factor, the conversion ratio of the electromotive force (voltage) on the tip velocity in vibration, has an important role in energy conversion process. First, the theoretical value of the force factor is formulated and then the validity was verified by experiments, where we compare four types of prototype with parameters of the dimension using 7.0 × 1.5 × 50 mm beams of Galfenol with 1606-turn wound coil. In addition, the energy conversion efficiency of the prototypes depending on load resistance was measured. The most efficient prototype exhibits the maximum instantaneous power of 0.73 W and energy of 4.7 mJ at a free vibration of frequency of 202 Hz in the case of applied force is 25 N. Further, it was found that energy conversion efficiency depends not only on the force factor but also on the damping (mechanical loss) of the vibration

  15. Ultra-Lightweight, High Efficiency Silicon-Carbide (SIC) Based Power Electronic Converters, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — This Small Business of Innovation Research Phase I proposal seeks to investigate and prove the feasibility of developing highly efficient, ultra-lightweight SiC...

  16. High Efficiency Quantum Dot III-V Multijunction Solar Cell for Space Power, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — We are proposing to utilize quantum dots to develop a super high-efficiency multijunction III-V solar cell for space. In metamorphic triple junction space solar...

  17. Highly-Efficient Thermoelectronic Conversion of Heat and Solar Radiation to Electric Power

    OpenAIRE

    Meir, Stefan

    2013-01-01

    Thermionic energy conversion has long been a candidate to convert solar radiation and the combustion heat of fossil fuels into electricity at high efficiencies. However, the formation of electron space charges has prevented the widespread use of the principle since its was first suggested in 1915. In this work, a novel mechanism to suppress the effects of the space charge was investigated: the acceleration of electrons in a special configuration of electric and magnetic fields. This work d...

  18. Ultra-high efficiency photovoltaic cells for large scale solar power generation.

    Science.gov (United States)

    Nakano, Yoshiaki

    2012-01-01

    The primary targets of our project are to drastically improve the photovoltaic conversion efficiency and to develop new energy storage and delivery technologies. Our approach to obtain an efficiency over 40% starts from the improvement of III-V multi-junction solar cells by introducing a novel material for each cell realizing an ideal combination of bandgaps and lattice-matching. Further improvement incorporates quantum structures such as stacked quantum wells and quantum dots, which allow higher degree of freedom in the design of the bandgap and the lattice strain. Highly controlled arrangement of either quantum dots or quantum wells permits the coupling of the wavefunctions, and thus forms intermediate bands in the bandgap of a host material, which allows multiple photon absorption theoretically leading to a conversion efficiency exceeding 50%. In addition to such improvements, microfabrication technology for the integrated high-efficiency cells and the development of novel material systems that realizes high efficiency and low cost at the same time are investigated.

  19. High efficiency H6 single-phase transformerless grid-tied PV inverter with proposed modulation for reactive power generation

    Science.gov (United States)

    Almasoudi, Fahad M.; Alatawi, Khaled S.; Matin, Mohammad

    2017-08-01

    Implementation of transformerless inverters in PV grid-tied system offer great benefits such as high efficiency, light weight, low cost, etc. Most of the proposed transformerless inverters in literature are verified for only real power application. Currently, international standards such as VDE-AR-N 4105 has demanded that PV grid-tied inverters should have the ability of controlling a specific amount of reactive power. Generation of reactive power cannot be accomplished in single phase transformerless inverter topologies because the existing modulation techniques are not adopted for a freewheeling path in the negative power region. This paper enhances a previous high efficiency proposed H6 trnasformerless inverter with SiC MOSFETs and demonstrates new operating modes for the generation of reactive power. A proposed pulse width modulation (PWM) technique is applied to achieve bidirectional current flow through freewheeling state. A comparison of the proposed H6 transformerless inverter using SiC MOSFETs and Si MOSFTEs is presented in terms of power losses and efficiency. The results show that reactive power control is attained without adding any additional active devices or modification to the inverter structure. Also, the proposed modulation maintains a constant common mode voltage (CM) during every operating mode and has low leakage current. The performance of the proposed system verifies its effectiveness in the next generation PV system.

  20. A High-Efficiency Compact SiC-based Power Converter System, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Wide-bandgap SiC semiconductors have been recently investigated for use in power devices, because of their potential capabilities of operating at high power...

  1. A High-Efficiency Compact SiC-based Power Converter System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Wide bandgap SiC power devices have the potential for reliable operations at higher junction temperatures, higher voltages, higher frequencies and thus higher power...

  2. Study on gas turbines. Leading role of high efficiency power generation; Gas turbine kenkyu. Kokoritsu hatsuden no shuyaku wo nerau

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-01-31

    This review summarizes research works of Central Research Institute of Electric Power Industry on gas turbines playing a leading role of high efficiency power generation. This article describes historical changes of gas turbine technology, changes and current status from the viewpoint of electric power industry, and development trend in various makers. Increase in the flow-in gas temperature, low NOx combustion technology, use of various fuels, and durability evaluation and improvement technology for high temperature parts are described as technological problems and development trends. The increase in temperature is indispensable for the improvement of efficiency. Materials having heat resistance, anticorrosion and strength are required. Accordingly, Ni-based single crystal super alloy has been developed. Developments of ceramic gas turbine and catalytic combustor are also described. The coal gasification combined power generation is expected as a new power generation technology having availability of various coals, high efficiency, and excellent environmental protection. Development of 1500 {degree}C class combustor for turbines has been promoted. Evaluation and improvement of durability of high temperature parts are also described. For the new utilization technology of gas turbines, repowering and compressed air storage gas turbine power generation technology are introduced. 92 figs., 14 tabs.

  3. Stable, high power, high efficiency picosecond ultraviolet generation at 355 nm in K3B6O10 Br crystal

    Science.gov (United States)

    Hou, Z. Y.; Wang, L. R.; Xia, M. J.; Yan, D. X.; Zhang, Q. L.; Zhang, L.; Liu, L. J.; Xu, D. G.; Zhang, D. X.; Wang, X. Y.; Li, R. K.; Chen, C. T.

    2018-06-01

    We demonstrate a high efficiency and high power picosecond ultraviolet source at 355 nm with stable output by sum frequency generation from a Nd:YAG laser using a type-I critically phase matched K3B6O10 Br crystal as nonlinear optical material. Conversion efficiency as high as 30.8% was achieved using a 25 ps laser at 1064 nm operated at 10 Hz. Similar work is done by using a 35 W 10 ps laser at 1064 nm as the pump source with a repetition rate of 80 MHz, and the highest average output power obtained was up to 5.3 W. In addition, the power stability of the 355 nm output power measurement shows that the standard deviation fluctuations of the average power are ±0.69% and ±0.91% at 3.0 W and 3.5 W, respectively.

  4. Switching coordination of distributed dc-dc converters for highly efficient photovoltaic power plants

    Science.gov (United States)

    Agamy, Mohammed; Elasser, Ahmed; Sabate, Juan Antonio; Galbraith, Anthony William; Harfman Todorovic, Maja

    2014-09-09

    A distributed photovoltaic (PV) power plant includes a plurality of distributed dc-dc converters. The dc-dc converters are configured to switch in coordination with one another such that at least one dc-dc converter transfers power to a common dc-bus based upon the total system power available from one or more corresponding strings of PV modules. Due to the coordinated switching of the dc-dc converters, each dc-dc converter transferring power to the common dc-bus continues to operate within its optimal efficiency range as well as to optimize the maximum power point tracking in order to increase the energy yield of the PV power plant.

  5. Self-Powered Wireless Smart Sensor Node Enabled by an Ultrastable, Highly Efficient, and Superhydrophobic-Surface-Based Triboelectric Nanogenerator.

    Science.gov (United States)

    Zhao, Kun; Wang, Zhong Lin; Yang, Ya

    2016-09-27

    Wireless sensor networks will be responsible for a majority of the fast growth in intelligent systems in the next decade. However, most of the wireless smart sensor nodes require an external power source such as a Li-ion battery, where the labor cost and environmental waste issues of replacing batteries have largely limited the practical applications. Instead of using a Li-ion battery, we report an ultrastable, highly efficient, and superhydrophobic-surface-based triboelectric nanogenerator (TENG) to scavenge wind energy for sustainably powering a wireless smart temperature sensor node. There is no decrease in the output voltage and current of the TENG after continuous working for about 14 h at a wind speed of 12 m/s. Through a power management circuit, the TENG can deliver a constant output voltage of 3.3 V and a pulsed output current of about 100 mA to achieve highly efficient energy storage in a capacitor. A wireless smart temperature sensor node can be sustainably powered by the TENG for sending the real-time temperature data to an iPhone under a working distance of 26 m, demonstrating the feasibility of the self-powered wireless smart sensor networks.

  6. High Efficiency GPS Block III L1 band Envelope Tracking Power Amplifier

    Science.gov (United States)

    2016-03-31

    intermo asymmetric ri nction and is d 30.69MHz w measured with pe Amplifier e CGH40120F Sub-System: F e RFPA and E Fig. 7: Nati The switcher the...Paul T. The Efficiency W ack Power Am Dongsu Ki Bumman, "Hi lator for Enve ess Componen Hassan, M. ing power-sup z LTE Envelop ts Conference

  7. High Efficiency Nuclear Power Plants Using Liquid Fluoride Thorium Reactor Technology

    Science.gov (United States)

    Juhasz, Albert J.; Rarick, Richard A.; Rangarajan, Rajmohan

    2009-01-01

    An overall system analysis approach is used to propose potential conceptual designs of advanced terrestrial nuclear power plants based on Oak Ridge National Laboratory (ORNL) Molten Salt Reactor (MSR) experience and utilizing Closed Cycle Gas Turbine (CCGT) thermal-to-electric energy conversion technology. In particular conceptual designs for an advanced 1 GWe power plant with turbine reheat and compressor intercooling at a 950 K turbine inlet temperature (TIT), as well as near term 100 MWe demonstration plants with TITs of 950 and 1200 K are presented. Power plant performance data were obtained for TITs ranging from 650 to 1300 K by use of a Closed Brayton Cycle (CBC) systems code which considered the interaction between major sub-systems, including the Liquid Fluoride Thorium Reactor (LFTR), heat source and heat sink heat exchangers, turbo-generator machinery, and an electric power generation and transmission system. Optional off-shore submarine installation of the power plant is a major consideration.

  8. A High-Efficient Low-Cost Converter for Capacitive Wireless Power Transfer Systems

    Directory of Open Access Journals (Sweden)

    Il-Oun Lee

    2017-09-01

    Full Text Available Growth of the Internet of Things (IoT spurs need for new ways of delivering power. Wireless power transfer (WPT has come into the spotlight from both academia and industry as a promising way to power the IoT devices. As one of the well-known WPT techniques, the capacitive power transfer (CPT has the merit of low electromagnetic radiation and amenability of combined power and data transfer over a capacitive interface. However, applying the CPT to the IoT devices is still challenging in reality. One of the major issues is due to the small capacitance of the capacitive interface, which results in low efficiency of the power transfer. To tackle this problem, we present a new step-up single-switch quasi-resonant (SSQR converter for the CPT system. To enhance the CPT efficiency, the proposed converter is designed to operate at low frequency and drive small current into the capacitive interfaces. In addition, by eliminating resistor-capacitor-diode (RCD snubber in the converter, we reduce the implementation cost of the CPT system. Based on intensive experimental work with a CPT system prototype that supports maximum 50 W (100 V/0.5 A power transfer, we demonstrate the functional correctness of the converter that achieves up to 93% efficiency.

  9. A high-efficiency self-powered wireless sensor node for monitoring concerning vibratory events

    Science.gov (United States)

    Xu, Dacheng; Li, Suiqiong; Li, Mengyang; Xie, Danpeng; Dong, Chuan; Li, Xinxin

    2017-09-01

    This paper presents a self-powered wireless alarming sensor node (SWASN), which was designed to monitor the occurrence of concerning vibratory events. The major components of the sensor node include a vibration-threshold-triggered energy harvester (VTTEH) that powers the sensor node, a dual threshold voltage control circuit (DTVCC) for power management and a radio frequency (RF) signal transmitting module. The VTTEH generates significant electric energy only when the input vibration reaches certain amplitude. Thus, the VTTEH serves as both the power source and the vibration-event-sensing element for the sensor node. The DTVCC was specifically designed to utilize the limited power supply from the VTTEH to operate the sensor node. Constructed with only voltage detectors and MOSFETs, the DTVCC achieved low power consumption, which was 65% lower compared with the power management circuit designed in our previous work. Meanwhile, a RF transmit circuit was constructed based on the commercially available CC1110-F32 wireless transceiver chip and a compact planar antenna was designed to improve the signal transmission distance. The sensor node was fabricated and was characterized both in the laboratory and in the field. Experimental results showed that the SWASN could automatically send out alarming signals when the simulated concerning event occurred. The waiting time between two consecutive transmission periods is less than 125 s and the transmission distance can reach 1.31 km. The SWASN will have broad applications in field surveillances.

  10. Compact high efficiency, light weight 200-800 MHz high power RF source

    International Nuclear Information System (INIS)

    Shrader, M.B.; Preist, D.H.

    1985-01-01

    There has long been a need for a new more efficient less bulky high power RF power source to drive accelerators in the 200 to 800 MHz region. Results on a recent 5-year EIMAC sponsored R and D program which have lead to the introduction of the Klystrode for UHF television and troposcatter applications indicate that at power levels of 1MW or more efficiencies in excess of 75% can be obtained at 450 MHz. Efficiencies of this order coupled with potential size and weight parameters which are a fraction of those of existing high power UHF generators open up new applications which heretofore would have been impractical if not impossible. Measurements at 470 MHz on existing Klystrodes are given. Projected operating conditions for a 1MW 450 MHz Klystrode having an overall length of 60 inches and a total tube, circuit, and magnet weight of 250 pounds is presented

  11. Polymer Separators for High-Power, High-Efficiency Microbial Fuel Cells

    KAUST Repository

    Chen, Guang; Wei, Bin; Luo, Yong; Logan, Bruce E.; Hickner, Michael A.

    2012-01-01

    Microbial fuel cells (MFCs) with hydrophilic poly(vinyl alcohol) (PVA) separators showed higher Coulombic efficiencies (94%) and power densities (1220 mW m-2) than cells with porous glass fiber separators or reactors without a separator after 32

  12. High-Efficiency, Nanowire Based Thermoelectric Devices for Radioisotope Power Conversion, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — This SBIR Phase I proposal responds to topic S3.03 of the 2010 NASA SBIR solicitation, for Power Generation and Conversion. Thermoelectric devices offer a simple and...

  13. Highly Efficient Wireless Powering for Autonomous Structural Health Monitoring and Test/Evaluation Systems

    Science.gov (United States)

    2016-07-27

    of this work is to improve the efficiency, range, and safety (in terms of EMI/EMC and signature) of wireless powering of sensors using the recently...this work is to improve the efficiency, range, and safety (in terms of EMI/EMC and signature) of wireless powering of sensors using the recently...Force and DoD, such as, smart runways, nano-satellites, smart skins for hypersonic vehicles , autonomous portable devices, integrated circuits, and

  14. Novel high efficient speed sensorless controller for maximum power extraction from wind energy conversion systems

    International Nuclear Information System (INIS)

    Fathabadi, Hassan

    2016-01-01

    Highlights: • Novel sensorless MPPT technique without drawbacks of other sensor/sensorless methods. • Tracking the actual MPP of WECSs, no tracking the MPP of their wind turbines. • Actually extracting the highest output power from WECSs. • Novel MPPT technique having the MPPT efficiency more than 98.5% for WECSs. • Novel MPPT technique having short convergence time for WECSs. - Abstract: In this study, a novel high accurate sensorless maximum power point tracking (MPPT) method is proposed. The technique tracks the actual maximum power point of a wind energy conversion system (WECS) at which maximum output power is extracted from the system, not the maximum power point of its wind turbine at which maximum mechanical power is obtained from the turbine, so it actually extracts the highest output power from the system. The technique only uses input voltage and current of the converter used in the system, and neither needs any speed sensors (anemometer and tachometer) nor has the drawbacks of other sensor/sensorless based MPPT methods. The technique has been implemented as a MPPT controller by constructing a WECS. Theoretical results, the technique performance, and its advantages are validated by presenting real experimental results. The real static-dynamic response of the MPPT controller is experimentally obtained that verifies the proposed MPPT technique high accurately extracts the highest instant power from wind energy conversion systems with the MPPT efficiency of more than 98.5% and a short convergence time that is only 25 s for the constructed system having a total inertia and friction coefficient of 3.93 kg m 2 and 0.014 N m s, respectively.

  15. A high-efficiency, low-noise power solution for a dual-channel GNSS RF receiver

    International Nuclear Information System (INIS)

    Shi Jian; Mo Taishan; Gan Yebing; Ma Chengyan; Ye Tianchun; Le Jianlian

    2012-01-01

    A high-efficiency low-noise power solution for a dual-channel GNSS RF receiver is presented. The power solution involves a DC—DC buck converter and a followed low-dropout regulator (LDO). The pulse-width-modulation (PWM) control method is adopted for better noise performance. An improved low-power high-frequency PWM control circuit is proposed, which halves the average quiescent current of the buck converter to 80 μA by periodically shutting down the OTA. The size of the output stage has also been optimized to achieve high efficiency under a light load condition. In addition, a novel soft-start circuit based on a current limiter has been implemented to avoid inrush current. Fabricated with commercial 180-nm CMOS technology, the DC—DC converter achieves a peak efficiency of 93.1% under a 2 MHz working frequency. The whole receiver consumes only 20.2 mA from a 3.3 V power supply and has a noise figure of 2.5 dB. (semiconductor integrated circuits)

  16. Wide-Range Highly-Efficient Wireless Power Receivers for Implantable Biomedical Sensors

    KAUST Repository

    Ouda, Mahmoud

    2016-11-01

    Wireless power transfer (WPT) is the key enabler for a myriad of applications, from low-power RFIDs, and wireless sensors, to wirelessly charged electric vehicles, and even massive power transmission from space solar cells. One of the major challenges in designing implantable biomedical devices is the size and lifetime of the battery. Thus, replacing the battery with a miniaturized wireless power receiver (WPRx) facilitates designing sustainable biomedical implants in smaller volumes for sentient medical applications. In the first part of this dissertation, we propose a miniaturized, fully integrated, wirelessly powered implantable sensor with on-chip antenna, designed and implemented in a standard 0.18μm CMOS process. As a batteryless device, it can be implanted once inside the body with no need for further invasive surgeries to replace batteries. The proposed single-chip solution is designed for intraocular pressure monitoring (IOPM), and can serve as a sustainable platform for implantable devices or IoT nodes. A custom setup is developed to test the chip in a saline solution with electrical properties similar to those of the aqueous humor of the eye. The proposed chip, in this eye-like setup, is wirelessly charged to 1V from a 5W transmitter 3cm away from the chip. In the second part, we propose a self-biased, differential rectifier with enhanced efficiency over an extended range of input power. A prototype is designed for the medical implant communication service (MICS) band at 433MHz. It demonstrates an efficiency improvement of more than 40% in the rectifier power conversion efficiency (PCE) and a dynamic range extension of more than 50% relative to the conventional cross-coupled rectifier. A sensitivity of -15.2dBm input power for 1V output voltage and a peak PCE of 65% are achieved for a 50k load. In the third part, we propose a wide-range, differential RF-to-DC power converter using an adaptive, self-biasing technique. The proposed architecture doubles

  17. Highly efficient solutions for smart and bulk power transmission of 'green energy'

    Energy Technology Data Exchange (ETDEWEB)

    Breuer, Wilfried; Retzmann, Dietmar; Uecker, Karl

    2010-09-15

    Environmental constraints, loss minimization and CO2 reduction will play an increasingly more important role in future. Security and sustainability of power supply as well as economic efficiency needs application of advanced technologies. Innovative solutions with HVDC (High Voltage Direct Current) and FACTS (Flexible AC Transmission Systems) have the potential to cope with these challenges. They provide the features which are necessary to avoid technical problems in power systems, they increase the transmission capacity and system stability very efficiently and help prevent cascading outages. Furthermore, they are essential for Grid Access of Renewable Energy Sources such as Hydro, Wind and Solar-Energy.

  18. A New Principle for a High Efficiency Power Audio Amplifier for Use with a Digital Preamplifier

    DEFF Research Database (Denmark)

    Jensen, Jørgen Arendt

    1986-01-01

    The use of class-B and class-D amlifiers for converting digital audio signals to analog signals is discussed. It is shown that the class-D amplifier is unsuitable due to distortion. Therefore, a new principle involving a switch-mode power supply and a class-B amplifier is suggested. By regulating...... the supply voltage to the amplifier according to the amplitude of the audio signal, a higher efficiency than can be obtained by the current principles is achieved. The regulation can be done very efficiently by generating the control signal to the power supply in advance of the audio signal, made possible...

  19. Highly efficient solutions for smart and bulk power transmission of 'green energy'

    Energy Technology Data Exchange (ETDEWEB)

    Breuer, Wilfried; Retzmann, Dietmar; Uecker, Karl

    2010-09-15

    Environmental constraints, loss minimization and CO2 reduction will play an increasingly more important role in future. Security and sustainability of power supply as well as economic efficiency needs application of advanced technologies. Innovative solutions with HVDC (High Voltage Direct Current) and FACTS (Flexible AC Transmission Systems) have the potential to cope with these challenges. They provide the features which are necessary to avoid technical problems in power systems, they increase the transmission capacity and system stability very efficiently and help prevent cascading outages. Furthermore, they are essential for Grid Access of Renewable Energy Sources such as Hydro, Wind and Solar-Energy.

  20. Ultra Clean 1.1MW High Efficiency Natural Gas Engine Powered System

    Energy Technology Data Exchange (ETDEWEB)

    Zurlo, James; Lueck, Steve

    2011-08-31

    Dresser, Inc. (GE Energy, Waukesha gas engines) will develop, test, demonstrate, and commercialize a 1.1 Megawatt (MW) natural gas fueled combined heat and power reciprocating engine powered package. This package will feature a total efficiency > 75% and ultra low CARB permitting emissions. Our modular design will cover the 1 – 6 MW size range, and this scalable technology can be used in both smaller and larger engine powered CHP packages. To further advance one of the key advantages of reciprocating engines, the engine, generator and CHP package will be optimized for low initial and operating costs. Dresser, Inc. will leverage the knowledge gained in the DOE - ARES program. Dresser, Inc. will work with commercial, regulatory, and government entities to help break down barriers to wider deployment of CHP. The outcome of this project will be a commercially successful 1.1 MW CHP package with high electrical and total efficiency that will significantly reduce emissions compared to the current central power plant paradigm. Principal objectives by phases for Budget Period 1 include: • Phase 1 – market study to determine optimum system performance, target first cost, lifecycle cost, and creation of a detailed product specification. • Phase 2 – Refinement of the Waukesha CHP system design concepts, identification of critical characteristics, initial evaluation of technical solutions, and risk mitigation plans. Background

  1. High-Efficiency and High-Power Mid-Wave Infrared Cascade Lasers

    Science.gov (United States)

    2009-08-01

    spreader and cold surface of the heat sink. Through collaborators of our team member at the Naval Research Labs, we have conducted acoustic imaging...detector. Power measurements were calibrated using a pyrometer detector. A gated integrator and boxcar averager with a 20 ns gate width was used

  2. High-Efficiency Solar-Powered 3-D Printers for Sustainable Development

    Directory of Open Access Journals (Sweden)

    Jephias Gwamuri

    2016-01-01

    Full Text Available The release of the open source 3-D printer known as the RepRap (a self-Replicating Rapid prototyper resulted in the potential for distributed manufacturing of products for significantly lower costs than conventional manufacturing. This development, coupled with open source-appropriate technology (OSAT, has enabled the opportunity for 3-D printers to be used for sustainable development. In this context, OSAT provides the opportunity to modify and improve the physical designs of their printers and desired digitally-shared objects. However, these 3-D printers require electricity while more than a billion people still lack electricity. To enable the utilization of RepRaps in off-grid communities, solar photovoltaic (PV-powered mobile systems have been developed, but recent improvements in novel delta-style 3-D printer designs allows for reduced costs and improved performance. This study builds on these innovations to develop and experimentally validate a mobile solar-PV-powered delta 3-D printer system. It is designed to run the RepRap 3-D printer regardless of solar flux. The electrical system design is tested outdoors for operating conditions: (1 PV charging battery and running 3-D printer; (2 printing under low insolation; (3 battery powering the 3-D printer alone; (4 PV charging the battery only; and (5 battery fully charged with PV-powered 3-D printing. The results show the system performed as required under all conditions providing feasibility for adoption in off-grid rural communities. 3-D printers powered by affordable mobile PV solar systems have a great potential to reduce poverty through employment creation, as well as ensuring a constant supply of scarce products for isolated communities.

  3. Polymer Separators for High-Power, High-Efficiency Microbial Fuel Cells

    KAUST Repository

    Chen, Guang

    2012-12-26

    Microbial fuel cells (MFCs) with hydrophilic poly(vinyl alcohol) (PVA) separators showed higher Coulombic efficiencies (94%) and power densities (1220 mW m-2) than cells with porous glass fiber separators or reactors without a separator after 32 days of operation. These remarkable increases in both the coublomic efficiency and the power production of the microbial fuel cells were made possible by the separator\\'s unique characteristics of fouling mitigation of the air cathode without a large increase in ionic resistance in the cell. This new type of polymer gel-like separator design will be useful for improving MFC reactor performance by enabling compact cell designs. © 2012 American Chemical Society.

  4. OVERVIEW OF A NEW METHOD FOR DESIGNING HIGH EFFICIENCY SMALL HYDRO POWER PLANTS

    Directory of Open Access Journals (Sweden)

    Milun Babić

    2010-01-01

    Full Text Available Significant number of research projects in the area of renewable energy sources (especially for small hydro power plants has been made within the Department for Energy and Process Engineering and Regional Euro Energy Efficiency Center at Faculty of Mechanical Engineering (University of Kragujevac, Serbia since early eighties. The results are various; numerous domestic and international recognition and technical performance tell about the success of the research. Research projects have been following the technical and technological development of research equipment and economy growth. This has led to the development of software for designing turbines of SHP plants. In order to notify the public about possibilities of our software, in this paper is briefly described a mathematical model and procedures for calculating and designing of SHPP for known conditions. As an argument for assessing the validity and potential of our research results is shown constructed SHP plant "Bosnia 1", 2 x 100 kW power.

  5. High-Efficiency Food Production in a Renewable Energy Based Micro-Grid Power System

    Science.gov (United States)

    Bubenheim, David; Meiners, Dennis

    2016-01-01

    Controlled Environment Agriculture (CEA) systems can be used to produce high-quality, desirable food year round, and the fresh produce can positively contribute to the health and well being of residents in communities with difficult supply logistics. While CEA has many positive outcomes for a remote community, the associated high electric demands have prohibited widespread implementation in what is typically already a fully subscribed power generation and distribution system. Recent advances in CEA technologies as well as renewable power generation, storage, and micro-grid management are increasing system efficiency and expanding the possibilities for enhancing community supporting infrastructure without increasing demands for outside supplied fuels. We will present examples of how new lighting, nutrient delivery, and energy management and control systems can enable significant increases in food production efficiency while maintaining high yields in CEA. Examples from Alaskan communities where initial incorporation of renewable power generation, energy storage and grid management techniques have already reduced diesel fuel consumption for electric generation by more than 40% and expanded grid capacity will be presented. We will discuss how renewable power generation, efficient grid management to extract maximum community service per kW, and novel energy storage approaches can expand the food production, water supply, waste treatment, sanitation and other community support services without traditional increases of consumable fuels supplied from outside the community. These capabilities offer communities with a range of choices to enhance their communities. The examples represent a synergy of technology advancement efforts to develop sustainable community support systems for future space-based human habitats and practical implementation of infrastructure components to increase efficiency and enhance health and well being in remote communities today and tomorrow.

  6. High-Efficiency Small-Scale Combined Heat and Power Organic Binary Rankine Cycles

    OpenAIRE

    Costante Mario Invernizzi; Nadeem Ahmed Sheikh

    2018-01-01

    Small-CHP (Combined Heat and Power) systems are generally considered a valuable technological option to the conventional boilers, in a technology developed context. If small-CHP systems are associated with the use of renewable energies (biomass, for example) they could play an important role in distributed generation even in developing countries or, in any case, where there are no extensive electricity networks. Traditionally the considered heat engines for micro- or mini-CHP are: the gas eng...

  7. Integration of direct carbon and hydrogen fuel cells for highly efficient power generation from hydrocarbon fuels

    Energy Technology Data Exchange (ETDEWEB)

    Muradov, Nazim; Choi, Pyoungho; Smith, Franklyn; Bokerman, Gary [Florida Solar Energy Center, University of Central Florida, 1679 Clearlake Road, Cocoa, FL 32922-5703 (United States)

    2010-02-15

    In view of impending depletion of hydrocarbon fuel resources and their negative environmental impact, it is imperative to significantly increase the energy conversion efficiency of hydrocarbon-based power generation systems. The combination of a hydrocarbon decomposition reactor with a direct carbon and hydrogen fuel cells (FC) as a means for a significant increase in chemical-to-electrical energy conversion efficiency is discussed in this paper. The data on development and operation of a thermocatalytic hydrocarbon decomposition reactor and its coupling with a proton exchange membrane FC are presented. The analysis of the integrated power generating system including a hydrocarbon decomposition reactor, direct carbon and hydrogen FC using natural gas and propane as fuels is conducted. It was estimated that overall chemical-to-electrical energy conversion efficiency of the integrated system varied in the range of 49.4-82.5%, depending on the type of fuel and FC used, and CO{sub 2} emission per kW{sub el}h produced is less than half of that from conventional power generation sources. (author)

  8. High-efficiency resonant coupled wireless power transfer via tunable impedance matching

    Science.gov (United States)

    Anowar, Tanbir Ibne; Barman, Surajit Das; Wasif Reza, Ahmed; Kumar, Narendra

    2017-10-01

    For magnetic resonant coupled wireless power transfer (WPT), the axial movement of near-field coupled coils adversely degrades the power transfer efficiency (PTE) of the system and often creates sub-resonance. This paper presents a tunable impedance matching technique based on optimum coupling tuning to enhance the efficiency of resonant coupled WPT system. The optimum power transfer model is analysed from equivalent circuit model via reflected load principle, and the adequate matching are achieved through the optimum tuning of coupling coefficients at both the transmitting and receiving end of the system. Both simulations and experiments are performed to evaluate the theoretical model of the proposed matching technique, and results in a PTE over 80% at close coil proximity without shifting the original resonant frequency. Compared to the fixed coupled WPT, the extracted efficiency shows 15.1% and 19.9% improvements at the centre-to-centre misalignment of 10 and 70 cm, respectively. Applying this technique, the extracted S21 parameter shows more than 10 dB improvements at both strong and weak couplings. Through the developed model, the optimum coupling tuning also significantly improves the performance over matching techniques using frequency tracking and tunable matching circuits.

  9. Combined Heat and Power Systems Technology Development and Demonstration 370 kW High Efficiency Microturbine

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2015-10-14

    The C370 Program was awarded in October 2010 with the ambitious goal of designing and testing the most electrically efficient recuperated microturbine engine at a rated power of less than 500 kW. The aggressive targets for electrical efficiency, emission regulatory compliance, and the estimated price point make the system state-of-the-art for microturbine engine systems. These goals will be met by designing a two stage microturbine engine identified as the low pressure spool and high pressure spool that are based on derivative hardware of Capstone’s current commercially available engines. The development and testing of the engine occurred in two phases. Phase I focused on developing a higher power and more efficient engine, that would become the low pressure spool which is based on Capstone’s C200 (200kW) engine architecture. Phase II integrated the low pressure spool created in Phase I with the high pressure spool, which is based on Capstone’s C65 (65 kW) commercially available engine. Integration of the engines, based on preliminary research, would allow the dual spool engine to provide electrical power in excess of 370 kW, with electrical efficiency approaching 42%. If both of these targets were met coupled with the overall CHP target of 85% total combined heating and electrical efficiency California Air Resources Board (CARB) level emissions, and a price target of $600 per kW, the system would represent a step change in the currently available commercial generation technology. Phase I of the C370 program required the development of the C370 low pressure spool. The goal was to increase the C200 engine power by a minimum of 25% — 250 kW — and efficiency from 32% to 37%. These increases in the C200 engine output were imperative to meet the power requirements of the engine when both spools were integrated. An additional benefit of designing and testing the C370 low pressure spool was the possibility of developing a stand-alone product for possible

  10. High efficiency 4H-SiC betavoltaic power sources using tritium radioisotopes

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, Christopher; Portnoff, Samuel [Widetronix Corp., Ithaca, New York 14850 (United States); Spencer, M. G. [Department of Electrical and Computer Engineering, Cornell University, Ithaca, New York 14850 (United States)

    2016-01-04

    Realization of an 18.6% efficient 4H-silicon carbide (4H-SiC) large area betavoltaic power source using the radioisotope tritium is reported. A 200 nm 4H-SiC P{sup +}N junction is used to collect high-energy electrons. The electron source is a titanium tritide (TiH{sup 3}{sub x}) foil, or an integrated titanium tritide region formed by the diffusion of tritium into titanium. The specific activity of the source is directly measured. Dark current measured under short circuit conditions was less than 6.1 pA/cm{sup 2}. Samples measured with an external tritium foil produced an open circuit voltage of 2.09 V, short circuit current of 75.47 nA/cm{sup 2}, fill factor of 0.86, and power efficiency of 18.6%. Samples measured with an integrated source produced power efficiencies of 12%. Simulations were done to determine the beta spectrum (modified by self absorption) exiting the source and the electron hole pair generation function in the 4H-SiC. The electron-hole pair generation function in 4H-SiC was modeled as a Gaussian distribution, and a closed form solution of the continuity equation was used to analyze the cell performance. The effective surface recombination velocity in our samples was found to be 10{sup 5}–10{sup 6 }cm/s. Our analysis demonstrated that the surface recombination dominates the performance of a tritium betavoltaic device but that using a thin P{sup +}N junction structure can mitigate some of the negative effects.

  11. A New Very-High-Efficiency R4 Converter for High-Power Fuel Cell Applications

    DEFF Research Database (Denmark)

    Nymand, Morten; Andersen, Michael Andreas E.

    2009-01-01

    of fullbridge switching stages and power transformers, operate in parallel on primary side and in series on secondary side. Current sharing is guaranteed by series connection of transformer secondary windings and three small cascaded current balancing transformers on primary side. The detailed design of a 10 k......W prototype converter is presented. Input voltage range is 30-60 V and output voltage is 800 V. Test results, including voltage- and current waveforms and efficiency measurements, are presented. A record high converter efficiency of 98.2 % is achieved. The proposed R4 boost converter thus constitutes a low...

  12. Development of a PF fired high efficiency power plant (AD700)

    Energy Technology Data Exchange (ETDEWEB)

    Blum, R.; Kjaer, S.; Bugge, J. [DONG Energy Generation, Fredericia (Denmark)

    2007-05-15

    European efforts to start substantial improvements of the performance of well established supercritical coal-fired power technology named the AD700 project began in 1998. Major targets were development of austenitic materials and nickel-based superalloys for the hottest sections of boilers, steam lines and turbines. Other targets were development of boiler and turbine designs for the more advanced conditions and finally economic viability of the AD700 technology has been investigated. The project has been very successful and 40 partners from the European power industry have worked together in several projects co-funded by the European Commission for nearly years. Procurement of mature and commercially optimised AD700 plant could take place around 2015. The investigated nickel-based materials have shown very high creep strengths but they have also shown to be very hard to manufacture, and more efforts to define new machining lines are being started. Ongoing tests indicate that the developed austenitic material will fulfil its creep strength target and is now ready for commercialisation. Development works on boiler and turbine designs for the advanced steam conditions have also been successfully completed but they also clearly indicate that further development work on improved ferritic steel for furnace walls is important. Conventional development of the steam cycles is based on new improved materials, which open for higher steam temperatures and efficiencies whereas other thermodynamic tools are only slowly being accepted. However, in the present paper a proposal for steam cycle improvements not based on higher steam temperatures is presented. The improved cycle is named the Master Cycle (MC) and it is based on a revision of the double reheat steam cycle where the bleeds of the IP turbines have been moved to a feed pump turbine bleeding on the first cold reheat line. Elsam has established protection of a patent for the MC in a number of countries. At constant main

  13. Managing the higher risks of low-cost high-efficiency advanced power generation technologies

    International Nuclear Information System (INIS)

    Pearson, M.

    1997-01-01

    Independent power producers operate large coal-fired installations and gas turbine combined-cycle (GTCC) facilities. Combined cycle units are complex and their reliability and availability is greatly influenced by mechanical, instrumentation and control weaknesses. It was suggested that these weaknesses could be avoided by tighter specifications and more rigorous functional testing before acceptance by the owner. For the present, the difficulties of developing reliable, lower installed cost/kw, more efficient GTCC designs, pressure for lower NO x emissions with 'dry' combustors continue to be the most difficult challenges for all GT manufacturers

  14. High-efficiency power transfer for silicon-based photonic devices

    Science.gov (United States)

    Son, Gyeongho; Yu, Kyoungsik

    2018-02-01

    We demonstrate an efficient coupling of guided light of 1550 nm from a standard single-mode optical fiber to a silicon waveguide using the finite-difference time-domain method and propose a fabrication method of tapered optical fibers for efficient power transfer to silicon-based photonic integrated circuits. Adiabatically-varying fiber core diameters with a small tapering angle can be obtained using the tube etching method with hydrofluoric acid and standard single-mode fibers covered by plastic jackets. The optical power transmission of the fundamental HE11 and TE-like modes between the fiber tapers and the inversely-tapered silicon waveguides was calculated with the finite-difference time-domain method to be more than 99% at a wavelength of 1550 nm. The proposed method for adiabatic fiber tapering can be applied in quantum optics, silicon-based photonic integrated circuits, and nanophotonics. Furthermore, efficient coupling within the telecommunication C-band is a promising approach for quantum networks in the future.

  15. A polygonal double-layer coil design for high-efficiency wireless power transfer

    Science.gov (United States)

    Mao, Shitong; Wang, Hao; Mao, Zhi-Hong; Sun, Mingui

    2018-05-01

    In this work, we present a novel coil structure for the design of Wireless Power Transfer (WPT) systems via magnetic resonant coupling. The new coil consists of two layers of flat polygonal windings in square, pentagonal and hexagonal shapes. The double-layer coil can be conveniently fabricated using the print circuit broad (PCB) technology. In our design, we include an angle between the two layers which can be adjusted to change the area of inter-layer overlap. This unique structure is thoroughly investigated with respect to the quality factor Q and the power transfer efficiency (PTE) using the finite element method (FEM). An equivalent circuit is derived and used to explain the properties of the angularly shifted double-layer coil theoretically. Comparative experiments are conducted from which the performance of the new coil is evaluated quantitatively. Our results have shown that an increased shift angle improves the Q-factor, and the optimal PTE is achieved when the angle reaches the maximum. When compared to the pentagonal and hexagonal coils, the square coil achieves the highest PTE due to its lowest parasitic capacitive effects. In summary, our new coil design improves the performance of WPT systems and allows a formal design procedure for optimization in a given application.

  16. Initial Screening of Thermochemical Water-Splitting Cycles for High Efficiency Generation of Hydrogen Fuels Using Nuclear Power

    International Nuclear Information System (INIS)

    Brown, L.C.; Funk, J.F.; Showalter, S.K.

    1999-01-01

    OAK B188 Initial Screening of Thermochemical Water-Splitting Cycles for High Efficiency Generation of Hydrogen Fuels Using Nuclear Power There is currently no large scale, cost-effective, environmentally attractive hydrogen production process, nor is such a process available for commercialization. Hydrogen is a promising energy carrier, which potentially could replace the fossil fuels used in the transportation sector of our economy. Fossil fuels are polluting and carbon dioxide emissions from their combustion are thought to be responsible for global warming. The purpose of this work is to determine the potential for efficient, cost-effective, large-scale production of hydrogen utilizing high temperature heat from an advanced nuclear power station. Almost 800 literature references were located which pertain to thermochemical production of hydrogen from water and over 100 thermochemical watersplitting cycles were examined. Using defined criteria and quantifiable metrics, 25 cycles have been selected for more detailed study

  17. Mixed-Signal Architectures for High-Efficiency and Low-Distortion Digital Audio Processing and Power Amplification

    Directory of Open Access Journals (Sweden)

    Pierangelo Terreni

    2010-01-01

    Full Text Available The paper addresses the algorithmic and architectural design of digital input power audio amplifiers. A modelling platform, based on a meet-in-the-middle approach between top-down and bottom-up design strategies, allows a fast but still accurate exploration of the mixed-signal design space. Different amplifier architectures are configured and compared to find optimal trade-offs among different cost-functions: low distortion, high efficiency, low circuit complexity and low sensitivity to parameter changes. A novel amplifier architecture is derived; its prototype implements digital processing IP macrocells (oversampler, interpolating filter, PWM cross-point deriver, noise shaper, multilevel PWM modulator, dead time compensator on a single low-complexity FPGA while off-chip components are used only for the power output stage (LC filter and power MOS bridge; no heatsink is required. The resulting digital input amplifier features a power efficiency higher than 90% and a total harmonic distortion down to 0.13% at power levels of tens of Watts. Discussions towards the full-silicon integration of the mixed-signal amplifier in embedded devices, using BCD technology and targeting power levels of few Watts, are also reported.

  18. High-Efficiency Small-Scale Combined Heat and Power Organic Binary Rankine Cycles

    Directory of Open Access Journals (Sweden)

    Costante Mario Invernizzi

    2018-04-01

    Full Text Available Small-CHP (Combined Heat and Power systems are generally considered a valuable technological option to the conventional boilers, in a technology developed context. If small-CHP systems are associated with the use of renewable energies (biomass, for example they could play an important role in distributed generation even in developing countries or, in any case, where there are no extensive electricity networks. Traditionally the considered heat engines for micro- or mini-CHP are: the gas engine, the gas turbine (with internal combustion, the steam engine, engine working according to the Stirling and to the Rankine cycles, the last with organic fluids. In principle, also fuel cells could be used. In this paper, we focus on small size Rankine cycles (10–15 k W with organic working fluids. The assumed heat source is hot combustion gases at high temperature (900–950 ∘ C and we assume to use only single stages axial turbines. The need to work at high temperatures, limits the choice of the right organic working fluids. The calculation results show the limitation in the performances of simple cycles and suggest the opportunity to resort to complex (binary cycle configurations to achieve high net conversion efficiencies (15–16%.

  19. Highly efficient power system based on direct fission fragment energy conversion utilizing magnetic collimation

    International Nuclear Information System (INIS)

    Tsvetkov, Pavel V.; Hart, Ron R.; Parish, Theodore A.

    2003-01-01

    The present study was focused on developing a technologically feasible power system that is based on direct fission fragment energy conversion utilizing magnetic collimation. The new concept is an attempt to combine several advantageous design solutions, which have been proposed for application in both fission and fusion reactors, into one innovative system that can offer exceptional energy conversion efficiency. The analysis takes into consideration a wide range of operational aspects including fission fragment escape from the fuel, collimation, collection, criticality, long-term performance, energy conversion efficiency, heat removal, and safety characteristics. Specific characteristics of the individual system components and the entire system are evaluated. Consistent analysis and evaluation of the technological feasibility of the concept were achieved using state-of-the-art computer codes that allowed realistic and consistent modeling. The calculated energy conversion efficiencies for the presented designs without a thermodynamic cycle and with the heavy water cycle are 52% and 62%, respectively. The analysis indicates that efficiencies up to 90% are potentially achievable. (author)

  20. Design of compact dispersion interferometer with a high efficiency nonlinear crystal and a low power CO2 laser

    Science.gov (United States)

    Akiyama, T.; Yoshimura, S.; Tomita, K.; Shirai, N.; Murakami, T.; Urabe, K.

    2017-12-01

    When the electron density of a plasma generated in high pressure environment is measured by a conventional interferometer, the phase shifts due to changes of the neutral gas density cause significant measurement errors. A dispersion interferometer, which measures the phase shift that arises from dispersion of medium between the fundamental and the second harmonic wavelengths of laser light, can suppress the measured phase shift due to the variations of neutral gas density. In recent years, the CO2 laser dispersion interferometer has been applied to the atmospheric pressure plasmas and its feasibility has been demonstrated. By combining a low power laser and a high efficiency nonlinear crystal for the second harmonic component generation, a compact dispersion interferometer can be designed. The optical design and preliminary experiments are conducted.

  1. A compact broadband high efficient X-band 9-watt PHEMT MMIC high-power amplifier for phased array radar applications

    NARCIS (Netherlands)

    Hek, A.P. de; Hunneman, P.A.H.; Demmler, M.; Hulsmann, A.

    1999-01-01

    ln this paper the development and measurement results of a compact broadband 9-Watt high efficient X-band high-power amplifier are discussed. The described amplifier has the following state-of-the art performance: an average ouput power of 9 Watt, a gain of 20 dB and an average Power Added

  2. Thermoeconomic analysis of a novel zero-CO{sub 2}-emission high-efficiency power cycle using LNG coldness

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Meng [China National Institute of Standardization, Beijing 100088 (China); Lior, Noam [Department of Mechanical Engineering and Applied Mechanics, University of Pennsylvania, Philadelphia, PA 19104-6315 (United States); Zhang, Na; Han, Wei [Institute of Engineering Thermophysics, Chinese Academy of Sciences, P.O. Box 2706, Beijing 100190 (China)

    2009-11-15

    This paper presents a thermoeconomic analysis aimed at the optimization of a novel zero-CO{sub 2} and other emissions and high-efficiency power and refrigeration cogeneration system, COOLCEP-S (Patent pending), which uses the liquefied natural gas (LNG) coldness during its revaporization. It was predicted that at the turbine inlet temperature (TIT) of 900 C, the energy efficiency of the COOLCEP-S system reaches 59%. The thermoeconomic analysis determines the specific cost, the cost of electricity, the system payback period and the total net revenue. The optimization started by performing a thermodynamic sensitivity analysis, which has shown that for a fixed TIT and pressure ratio, the pinch point temperature difference in the recuperator, {delta}T{sub p1}, and that in the condenser, {delta}T{sub p2} are the most significant unconstrained variables to have a significant effect on the thermal performance of novel cycle. The payback period of this novel cycle (with fixed net power output of 20 MW and plant life of 40 years) was {proportional_to}5.9 years at most, and would be reduced to {proportional_to}3.1 years at most when there is a market for the refrigeration byproduct. The capital investment cost of the economically optimized plant is estimated to be about 1000 /kWe, and the cost of electricity is estimated to be 0.34-0.37 CNY/kWh ({proportional_to}0.04 USD/kWh). These values are much lower than those of conventional coal power plants being installed at this time in China, which, in contrast to COOLCEP-S, do produce CO{sub 2} emissions at that. (author)

  3. Thermoeconomic analysis of a novel zero-CO{sub 2}-emission high-efficiency power cycle using LNG coldness

    Energy Technology Data Exchange (ETDEWEB)

    Liu Meng [China National Institute of Standardization, Beijing 100088 (China)], E-mail: liumeng@cnis.gov.cn; Lior, Noam [Department of Mechanical Engineering and Applied Mechanics, University of Pennsylvania, Philadelphia, PA 19104-6315 (United States)], E-mail: lior@seas.upenn.edu; Zhang Na; Han Wei [Institute of Engineering Thermophysics, Chinese Academy of Sciences, P.O. Box 2706, Beijing 100190 (China)

    2009-11-15

    This paper presents a thermoeconomic analysis aimed at the optimization of a novel zero-CO{sub 2} and other emissions and high-efficiency power and refrigeration cogeneration system, COOLCEP-S (Patent pending), which uses the liquefied natural gas (LNG) coldness during its revaporization. It was predicted that at the turbine inlet temperature (TIT) of 900 deg. C, the energy efficiency of the COOLCEP-S system reaches 59%. The thermoeconomic analysis determines the specific cost, the cost of electricity, the system payback period and the total net revenue. The optimization started by performing a thermodynamic sensitivity analysis, which has shown that for a fixed TIT and pressure ratio, the pinch point temperature difference in the recuperator, {delta}T{sub p1}, and that in the condenser, {delta}T{sub p2} are the most significant unconstrained variables to have a significant effect on the thermal performance of novel cycle. The payback period of this novel cycle (with fixed net power output of 20 MW and plant life of 40 years) was {approx}5.9 years at most, and would be reduced to {approx}3.1 years at most when there is a market for the refrigeration byproduct. The capital investment cost of the economically optimized plant is estimated to be about 1000 $/kWe, and the cost of electricity is estimated to be 0.34-0.37 CNY/kWh ({approx}0.04 $/kWh). These values are much lower than those of conventional coal power plants being installed at this time in China, which, in contrast to COOLCEP-S, do produce CO{sub 2} emissions at that.

  4. Performance study of highly efficient 520 W average power long pulse ceramic Nd:YAG rod laser

    Science.gov (United States)

    Choubey, Ambar; Vishwakarma, S. C.; Ali, Sabir; Jain, R. K.; Upadhyaya, B. N.; Oak, S. M.

    2013-10-01

    We report the performance study of a 2% atomic doped ceramic Nd:YAG rod for long pulse laser operation in the millisecond regime with pulse duration in the range of 0.5-20 ms. A maximum average output power of 520 W with 180 J maximum pulse energy has been achieved with a slope efficiency of 5.4% using a dual rod configuration, which is the highest for typical lamp pumped ceramic Nd:YAG lasers. The laser output characteristics of the ceramic Nd:YAG rod were revealed to be nearly equivalent or superior to those of high-quality single crystal Nd:YAG rod. The laser pump chamber and resonator were designed and optimized to achieve a high efficiency and good beam quality with a beam parameter product of 16 mm mrad (M2˜47). The laser output beam was efficiently coupled through a 400 μm core diameter optical fiber with 90% overall transmission efficiency. This ceramic Nd:YAG laser will be useful for various material processing applications in industry.

  5. The in-situ testing of high efficiency particulate filters in the CEGB south eastern region nuclear power stations

    International Nuclear Information System (INIS)

    Powell, A.W.; Wilkinson, B.A.

    1977-01-01

    High efficiency air filters are installed in the CEGB's Nuclear Power Stations to prevent discharge of radioactive material to the environment should the ventilation air become contaminated. The Board has determined that these filter units should be tested in-situ to ensure that the stringent design specifications are met. This paper describes the rig work comparing the British Standard method using sodium chloride aerosol with other test methods, such as Dioctyl Phthalate, naturally occurring dust aerosols and artificially produced condensation nuclei. This work led to the development of an in-situ test method using condensation nuclei and a Pollak-Nolan nucleus counter. The advantages and disadvantages of this method over other methods for in-situ testing is discussed. The test method has been used in the South Eastern Region for several years and considerable experience has been gained in its use on a wide variety of filter systems. The method adopted for each system is detailed including the injection, sampling and interpretation of the results obtained. Numerous faults and difficulties have been highlighted from the design, installation and filter changing aspects

  6. Report of high efficiency waste power generation technology development in 1995; Kokoritsu haikibutsu hatsuden gijutsu kaihatsu (1995 nendo hokokusho)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-03-01

    High temperature and high pressure steam has been investigated for the high efficiency waste power generation technology development. The steam temperature below 300 centigrade is currently employed to avoid the corrosion of superheater, and the generating efficiency is less than 15%. Practical application of 500 centigrade and 100 kg/cm{sup 2} is planned by developing corrosion resistance materials. Environmental load reduction technology has been also developed. For the external circulation type fluidized bed furnace combustion tests using dummy waste in fiscal 1995, the temperature control at bag filter was effective for suppressing the dioxins. When using waste plastics, HCl could be reduced by blowing Ca compounds. Various Cr-Ni-Mo-based alloys have been developed as a corrosion resistance superheater tube material, and are currently tested. For the environmental load reduction technology, the development of pulse plasma exhaust gas treatment method has been continued from fiscal 1993. In fiscal 1995, this method was confirmed using a small-scale test unit, and also tested using a 5000 Nm{sup 3}/h bench-scale unit. The removal rates of dioxins at the outlet of bag filter were 99.8% and 99.3%, respectively. They were found to be affected greatly by the pulse waveform. 13 refs., 107 figs., 24 tabs.

  7. Development of technologies on innovative-simplified nuclear power plant using high-efficiency steam injectors (2) analysis of heat balance of innovative-simplified nuclear power plant

    International Nuclear Information System (INIS)

    Goto, S.; Ohmori, S.; Mori, M.

    2005-01-01

    It is possible to establish simplified system with reduced space and total equipment weight using high-efficiency Steam Injector (SI) instead of low-pressure feedwater heaters in Nuclear Power Plant (NPP)(1)-(6). The SI works as a heat exchanger through direct contact between feedwater from the condensers and extracted steam from the turbines. It can get a higher pressure than supplied steam pressure, so it can reduce the feedwater pumps. The maintenance and reliability are still higher because SI has no movable parts. This paper describes the analysis of the heat balance and plant efficiency of this Innovative- Simplified NPP with high-efficiency SI. The plant efficiency is compared with the electric power of 1100MWe-class BWR system and the Innovative- Simplified BWR system with SI. The SI model is adapted into the heat balance simulator with a simplified model. The results show plant efficiencies of the Innovated-Simplified BWR system are almost equal to the original BWR one. The present research is one of the projects that are carried out by Tokyo Electric Power Company, Toshiba Corporation, and six Universities in Japan, funded from the Institute of Applied Energy (IAE) of Japan as the national public research-funded program. (authors)

  8. Development of technologies on innovative-simplified nuclear power plant using high-efficiency steam injectors. (2) Analysis of heat balance of innovative-simplified nuclear power plant

    International Nuclear Information System (INIS)

    Goto, Shoji; Ohmori, Shuichi; Mori, Mitchitsugu

    2004-01-01

    It is possible to established simplified systems and reduced space and equipments using high-efficiency Steam Injector (SI) instead of low-pressure feed water heaters in Nuclear Power Plant (NPP). The SI works as a heat exchanger through direct contact between feedwater from condenser and extracted steam from turbine. It can get a higher pressure than supplied steam pressure, so it can reduce the feedwater pumps. The maintenance and reliability are still higher because SI has no movable parts. This paper describes the analysis of the heat balance and plant efficiency of this Innovative-Simplified NPP with high-efficiency SI. The plant efficiency is compared with the electric power of 1100MWe class original BWR system and the Innovative-Simplified BWR system with SI. The SI model is adapted into the heat balance simulator with a simplified model. The results show plant efficiencies of the Innovated-Simplified BWR system are almost equal to the original BWR one. The present research is one of the projects that are carried out by Tokyo Electric Power Company, Toshiba Corporation, and six Universities in Japan, funded from the Institute of Applied Energy (IAE) of Japan as the national public research-funded program. (author)

  9. Models and simulation of non-ideal fluid flows in unconventional turbomachinery : Toward highly efficient next-generation green power systems

    NARCIS (Netherlands)

    Rinaldi, E.

    2015-01-01

    The new generation of power plants based on innovative thermodynamic cycles operating with unconventional working fluids, such as CO2 close to its thermodynamic critical point or organic fluids close to their vapour saturation line, is an attractive option for high efficiency conversion of

  10. A highly efficient Micro-Power Converter between a Solar Cell and a Rechargable Lithium-ion Battery

    NARCIS (Netherlands)

    Woerd, van der A.C.; Bais, M.A.; Jong, de L.P.; Roermund, van A.H.M.; Varandan, V.K.; Singer, R.A.; Vellekoop, M.J.

    1998-01-01

    This paper describes the design of a low-power photo-voltaic power converter which will be used in a directional hearing aid. It is argued, that the use of a switched-capacitor converter is needed when integration on a chip is demanded. This converter combined with a parallel power converter has an

  11. Design of a high-efficiency train headlamp with low power consumption using dual half-parabolic aluminized reflectors.

    Science.gov (United States)

    Liang, Wei-Lun; Su, Guo-Dung J

    2018-02-20

    We propose a train headlamp system using dual half-circular parabolic aluminized reflectors. Each half-circular reflector contains five high-efficiency and small-package light-emitting diode (LED) chips, and the halves are 180° rotationally symmetric. For traffic safety, the headlamp satisfies the Code of Federal Regulations. To predict the pattern of illumination, an analytical derivation is developed for the optical path of a ray that is perpendicular to and emitted from the center of an LED chip. This ray represents the main ray emitted from the LED chip and is located at the maximum illuminance of the spot projected by the LED source onto a screen. We then analyze the design systematically to determine the locations of the LED chips in the reflector that minimize electricity consumption while satisfying reliability constraints associated with traffic safety. Compared to a typical train headlamp system with an incandescent or halogen lamp needing several hundred watts, the proposed system only uses 20.18 W to achieve the luminous intensity requirements.

  12. New highly efficient piezoceramic materials

    International Nuclear Information System (INIS)

    Dantsiger, A.Ya.; Razumovskaya, O.N.; Reznichenko, L.A.; Grineva, L.D.; Devlikanova, R.U.; Dudkina, S.I.; Gavrilyachenko, S.V.; Dergunova, N.V.

    1993-01-01

    New high efficient piezoceramic materials with various combination of parameters inclusing high Curie point for high-temperature transducers using in atomic power engineering are worked. They can be used in systems for heated matters nondestructive testing, controllers for varied industrial power plants and other high-temperature equipment

  13. High Efficiency Hybrid Energy Storage Utilizing High Power Density Ultracapacitors For Long Duration Balloon Flights, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — FastCAP proposes to develop an ultra-high power density and high frequency ultracapacitor capable of surviving over the wide temperature range of -60C to 130C and...

  14. High-Efficiency, Ka-band Solid-State Power Amplifier Utilizing GaN Technology, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — QuinStar Technology proposes to develop an efficient, solid-state power amplifier (SSPA), operating at Ka-band frequencies, for high data rate, long range space...

  15. 16 W output power by high-efficient spectral beam combining of DBR-tapered diode lasers

    DEFF Research Database (Denmark)

    Müller, André; Vijayakumar, Deepak; Jensen, Ole Bjarlin

    2011-01-01

    output power achieved by spectral beam combining of two single element tapered diode lasers. Since spectral beam combining does not affect beam propagation parameters, M2-values of 1.8 (fast axis) and 3.3 (slow axis) match the M2- values of the laser with lowest spatial coherence. The principle......Up to 16 W output power has been obtained using spectral beam combining of two 1063 nm DBR-tapered diode lasers. Using a reflecting volume Bragg grating, a combining efficiency as high as 93.7% is achieved, resulting in a single beam with high spatial coherence. The result represents the highest...... of spectral beam combining used in our experiments can be expanded to combine more than two tapered diode lasers and hence it is expected that the output power may be increased even further in the future....

  16. 16 W output power by high-efficient spectral beam combining of DBR-tapered diode lasers.

    Science.gov (United States)

    Müller, André; Vijayakumar, Deepak; Jensen, Ole Bjarlin; Hasler, Karl-Heinz; Sumpf, Bernd; Erbert, Götz; Andersen, Peter E; Petersen, Paul Michael

    2011-01-17

    Up to 16 W output power has been obtained using spectral beam combining of two 1063 nm DBR-tapered diode lasers. Using a reflecting volume Bragg grating, a combining efficiency as high as 93.7% is achieved, resulting in a single beam with high spatial coherence. The result represents the highest output power achieved by spectral beam combining of two single element tapered diode lasers. Since spectral beam combining does not affect beam propagation parameters, M2-values of 1.8 (fast axis) and 3.3 (slow axis) match the M2-values of the laser with lowest spatial coherence. The principle of spectral beam combining used in our experiments can be expanded to combine more than two tapered diode lasers and hence it is expected that the output power may be increased even further in the future.

  17. A new principle for a high-efficiency power audio amplifier for use with a digital preamplifier

    DEFF Research Database (Denmark)

    Jensen, Jørgen Arendt

    1987-01-01

    The use of class-B and class-D amplifiers for converting digital audio signals to analog signals is discussed. It is shown that the class-D amplifier is unsuitable due to distortion. Therefore a new principle involving a switch-mode power supply and a class-B amplifier is suggested. By regulating...... the supply voltage to the amplifier according to the amplitude of the audio signal, a higher efficiency than can be obtained by the usual principles is achieved. The regulation can be done very efficiently by generating the control signal to the power supply in advance of the audio signal, made possible...

  18. High-Efficiency Isolated Boost DCDC Converter for High-Power Low-Voltage Fuel-Cell Applications

    DEFF Research Database (Denmark)

    Nymand, Morten; Andersen, Michael A. E.

    2010-01-01

    high winding losses. The analysis of transformer leakage inductance reveals that extremely low leakage inductance can be achieved, allowing stored energy to be dissipated. Power MOSFETs fully rated for repetitive avalanches allow primary-side voltage clamp circuits to be eliminated. The oversizing...

  19. Techno-Economic Feasibility of Highly Efficient Cost-Effective Thermoelectric-SOFC Hybrid Power Generation Systems

    Energy Technology Data Exchange (ETDEWEB)

    Jifeng Zhang; Jean Yamanis

    2007-09-30

    Solid oxide fuel cell (SOFC) systems have the potential to generate exhaust gas streams of high temperature, ranging from 400 to 800 C. These high temperature gas streams can be used for additional power generation with bottoming cycle technologies to achieve higher system power efficiency. One of the potential candidate bottoming cycles is power generation by means of thermoelectric (TE) devices, which have the inherent advantages of low noise, low maintenance and long life. This study was to analyze the feasibility of combining coal gas based SOFC and TE through system performance and cost techno-economic modeling in the context of multi-MW power plants, with 200 kW SOFC-TE module as building blocks. System and component concepts were generated for combining SOFC and TE covering electro-thermo-chemical system integration, power conditioning system (PCS) and component designs. SOFC cost and performance models previously developed at United Technologies Research Center were modified and used in overall system analysis. The TE model was validated and provided by BSST. The optimum system in terms of energy conversion efficiency was found to be a pressurized SOFC-TE, with system efficiency of 65.3% and cost of $390/kW of manufacturing cost. The pressurization ratio was approximately 4 and the assumed ZT of the TE was 2.5. System and component specifications were generated based on the modeling study. The major technology and cost barriers for maturing the system include pressurized SOFC stack using coal gas, the high temperature recycle blowers, and system control design. Finally, a 4-step development roadmap is proposed for future technology development, the first step being a 1 kW proof-of-concept demonstration unit.

  20. High-efficiency space-based software radio architectures & algorithms (a minimum size, weight, and power TeraOps processor)

    Energy Technology Data Exchange (ETDEWEB)

    Dunham, Mark Edward [Los Alamos National Laboratory; Baker, Zachary K [Los Alamos National Laboratory; Stettler, Matthew W [Los Alamos National Laboratory; Pigue, Michael J [Los Alamos National Laboratory; Schmierer, Eric N [Los Alamos National Laboratory; Power, John F [Los Alamos National Laboratory; Graham, Paul S [Los Alamos National Laboratory

    2009-01-01

    Los Alamos has recently completed the latest in a series of Reconfigurable Software Radios, which incorporates several key innovations in both hardware design and algorithms. Due to our focus on satellite applications, each design must extract the best size, weight, and power performance possible from the ensemble of Commodity Off-the-Shelf (COTS) parts available at the time of design. In this case we have achieved 1 TeraOps/second signal processing on a 1920 Megabit/second datastream, while using only 53 Watts mains power, 5.5 kg, and 3 liters. This processing capability enables very advanced algorithms such as our wideband RF compression scheme to operate remotely, allowing network bandwidth constrained applications to deliver previously unattainable performance.

  1. Highly efficient and reliable high power LEDs with patterned sapphire substrate and strip-shaped distributed current blocking layer

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Shengjun [School of Power and Mechanical Engineering, Wuhan University, Wuhan 430072 (China); State Key Laboratory of Mechanical System and Vibration, School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); Yuan, Shu; Liu, Yingce [Quantum Wafer Inc., Foshan 528251 (China); Guo, L. Jay [Department of Electrical Engineering and Computer Science, University of Michigan, Ann Arbor, MI 48109 (United States); Liu, Sheng, E-mail: victor_liu63@126.com [School of Power and Mechanical Engineering, Wuhan University, Wuhan 430072 (China); Ding, Han [State Key Laboratory of Mechanical System and Vibration, School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China)

    2015-11-15

    Graphical abstract: - Highlights: • TEM is used to characterize threading dislocation existing in GaN epitaxial layer. • Effect of threading dislocation on optical and electrical of LEDs is discussed. • Strip-shaped SiO{sub 2} DCBL is designed to improve current spreading performance of LEDs. - Abstract: We demonstrated that the improvement in optical and electrical performance of high power LEDs was achieved using cone-shaped patterned sapphire substrate (PSS) and strip-shaped SiO{sub 2} distributed current blocking layer (DCBL). We found through transmission electron microscopy (TEM) observation that densities of both the screw dislocation and edge dislocation existing in GaN epitaxial layer grown on PSS were much less than that of GaN epitaxial layer grown on flat sapphire substrate (FSS). Compared to LED grown on FSS, LED grown on PSS showed higher sub-threshold forward-bias voltage and lower reverse leakage current, resulting in an enhancement in device reliability. We also designed a strip-shaped SiO{sub 2} DCBL beneath a strip-shaped p-electrode, which prevents the current from being concentrated on regions immediately adjacent the strip-shaped p-electrode, thereby facilitating uniform current spreading into the active region. By implementing strip-shaped SiO{sub 2} DCBL, light output power of high power PSS-LED chip could be further increased by 13%.

  2. Nanofluidic crystal: a facile, high-efficiency and high-power-density scaling up scheme for energy harvesting based on nanofluidic reverse electrodialysis

    International Nuclear Information System (INIS)

    Ouyang Wei; Wang Wei; Zhang Haixia; Wu Wengang; Li Zhihong

    2013-01-01

    The great advances in nanotechnology call for advances in miniaturized power sources for micro/nano-scale systems. Nanofluidic channels have received great attention as promising high-power-density substitutes for ion exchange membranes for use in energy harvesting from ambient ionic concentration gradient, namely reverse electrodialysis. This paper proposes the nanofluidic crystal (NFC), of packed nanoparticles in micro-meter-sized confined space, as a facile, high-efficiency and high-power-density scaling-up scheme for energy harvesting by nanofluidic reverse electrodialysis (NRED). Obtained from the self-assembly of nanoparticles in a micropore, the NFC forms an ion-selective network with enormous nanochannels due to electrical double-layer overlap in the nanoparticle interstices. As a proof-of-concept demonstration, a maximum efficiency of 42.3 ± 1.84%, a maximum power density of 2.82 ± 0.22 W m −2 , and a maximum output power of 1.17 ± 0.09 nW/unit (nearly three orders of magnitude of amplification compared to other NREDs) were achieved in our prototype cell, which was prepared within 30 min. The current NFC-based prototype cell can be parallelized and cascaded to achieve the desired output power and open circuit voltage. This NFC-based scaling-up scheme for energy harvesting based on NRED is promising for the building of self-powered micro/nano-scale systems. (paper)

  3. Thermodynamic Model of a Very High Efficiency Power Plant based on a Biomass Gasifier, SOFCs, and a Gas Turbine

    Directory of Open Access Journals (Sweden)

    P V Aravind

    2012-07-01

    Full Text Available Thermodynamic calculations with a power plant based on a biomass gasifier, SOFCs and a gas turbine are presented. The SOFC anode off-gas which mainly consists of steam and carbon dioxides used as a gasifying agent leading to an allothermal gasification process for which heat is required. Implementation of heat pipes between the SOFC and the gasifier using two SOFC stacks and intercooling the fuel and the cathode streams in between them has shown to be a solution on one hand to drive the allothermal gasification process and on the other hand to cool down the SOFC. It is seen that this helps to reduce the exergy losses in the system significantly. With such a system, electrical efficiency around 73% is shown as achievable.

  4. A High Efficiency Charging Strategy for a Supercapacitor Using a Wireless Power Transfer System Based on Inductor/Capacitor/Capacitor (LCC Compensation Topology

    Directory of Open Access Journals (Sweden)

    Yuyu Geng

    2017-01-01

    Full Text Available In the application of rail transit vehicles, when using typical wireless power transfer (WPT systems with series–series (SS compensation supply power for supercapacitors, the output current is in an approximately inverse relationship with the duty cycle in a wide range. This renders the typical buck circuit control inappropriate. In order to help resolve the above issues, this paper designs inductor/capacitor/capacitor (LCC compensation with new compensation parameters, which can achieve an adjustable quasi-constant voltage from the input of the inverter to the output of the rectifier. In addition, the two-port network method is used to analyze the resonant compensation circuit. The analysis shows that LCC compensation is more suitable for the WPT system using the supercapacitor as the energy storage device. In the case of LCC compensation topology combined with the charging characteristics of the supercapacitor, an efficient charging strategy is designed, namely first constant current charging, followed by constant power charging. Based on the analysis of LCC compensation, the system has an optimal load, by which the system works at the maximum efficiency point. Combined with the characteristics of the constant voltage output, the system can maintain high efficiency in the constant power stage by making constant output power the same as the optimal power point. Finally, the above design is verified through experiments.

  5. Report on the fiscal 1996 development of high efficient waste power generation technology; 1996 nendo kokoritsu haikibutsu hatsuden gijutsu kaihatsu hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    The technical development was made by which high-temperature/high-pressure steam is generated in the incineration furnace using general waste, combustible industrial waste, etc. as fuel to generate power high efficiently, and reliability of the superheater, etc. was verified by the pilot plant. For it, the following were conducted: development of element technology (high-temperature/high-efficiency combustion furnace, corrosion resistant super heater materials, environmental load reduction technology) and the demonstration (demonstrative test in pilot plant, study of an optimum total system). In relation to the external circulation type fluidized bed furnace, reformation was made which enables simultaneous sampling of dioxins, etc. The combustion test was done using the reformed combustion testing furnace to obtain the data necessary for the study of formation/decomposition mechanism of dioxin. The amount of corrosion reduction of superheater sample material for pilot plant use was determined. A study was made of improvement of removal of dioxins and NOx in the pulse plasma exhaust gas treatment method. The pilot plant was installed. 10 refs., 205 figs., 79 tabs.

  6. Investigation of High-Efficiency Wireless Power Transfer Criteria of Resonantly-Coupled Loops and Dipoles through Analysis of the Figure of Merit

    Directory of Open Access Journals (Sweden)

    Charles Moorey

    2015-10-01

    Full Text Available The efficiency of a Wireless Power Transfer (WPT system is greatly dependent on both the geometry and operating frequency of the transmitting and receiving structures. By using Coupled Mode Theory (CMT, the figure of merit is calculated for resonantly-coupled loop and dipole systems. An in-depth analysis of the figure of merit is performed with respect to the key geometric parameters of the loops and dipoles, along with the resonant frequency, in order to identify the key relationships leading to high-efficiency WPT. For systems consisting of two identical single-turn loops, it is shown that the choice of both the loop radius and resonant frequency are essential in achieving high-efficiency WPT. For the dipole geometries studied, it is shown that the choice of length is largely irrelevant and that as a result of their capacitive nature, low-MHz frequency dipoles are able to produce significantly higher figures of merit than those of the loops considered. The results of the figure of merit analysis are used to propose and subsequently compare two mid-range loop and dipole WPT systems of equal size and operating frequency, where it is shown that the dipole system is able to achieve higher efficiencies than the loop system of the distance range examined.

  7. BInGaN alloys nearly lattice-matched to GaN for high-power high-efficiency visible LEDs

    Science.gov (United States)

    Williams, Logan; Kioupakis, Emmanouil

    2017-11-01

    InGaN-based visible light-emitting diodes (LEDs) find commercial applications for solid-state lighting and displays, but lattice mismatch limits the thickness of InGaN quantum wells that can be grown on GaN with high crystalline quality. Since narrower wells operate at a higher carrier density for a given current density, they increase the fraction of carriers lost to Auger recombination and lower the efficiency. The incorporation of boron, a smaller group-III element, into InGaN alloys is a promising method to eliminate the lattice mismatch and realize high-power, high-efficiency visible LEDs with thick active regions. In this work, we apply predictive calculations based on hybrid density functional theory to investigate the thermodynamic, structural, and electronic properties of BInGaN alloys. Our results show that BInGaN alloys with a B:In ratio of 2:3 are better lattice matched to GaN compared to InGaN and, for indium fractions less than 0.2, nearly lattice matched. Deviations from Vegard's law appear as bowing of the in-plane lattice constant with respect to composition. Our thermodynamics calculations demonstrate that the solubility of boron is higher in InGaN than in pure GaN. Varying the Ga mole fraction while keeping the B:In ratio constant enables the adjustment of the (direct) gap in the 1.75-3.39 eV range, which covers the entire visible spectrum. Holes are strongly localized in non-bonded N 2p states caused by local bond planarization near boron atoms. Our results indicate that BInGaN alloys are promising for fabricating nitride heterostructures with thick active regions for high-power, high-efficiency LEDs.

  8. Performance Analysis of Multiradio Transmitter with Polar or Cartesian Architectures Associated with High Efficiency Switched-Mode Power Amplifiers (invited paper

    Directory of Open Access Journals (Sweden)

    F. Robert

    2010-12-01

    Full Text Available This paper deals with wireless multi-radio transmitter architectures operating in the frequency band of 800 MHz – 6 GHz. As a consequence of the constant evolution in the communication systems, mobile transmitters must be able to operate at different frequency bands and modes according to existing standards specifications. The concept of a unique multiradio architecture is an evolution of the multistandard transceiver characterized by a parallelization of circuits for each standard. Multi-radio concept optimizes surface and power consumption. Transmitter architectures using sampling techniques and baseband ΣΔ or PWM coding of signals before their amplification appear as good candidates for multiradio transmitters for several reasons. They allow using high efficiency power amplifiers such as switched-mode PAs. They are highly flexible and easy to integrate because of their digital nature. But when the transmitter efficiency is considered, many elements have to be taken into account: signal coding efficiency, PA efficiency, RF filter. This paper investigates the interest of these architectures for a multiradio transmitter able to support existing wireless communications standards between 800 MHz and 6 GHz. It evaluates and compares the different possible architectures for WiMAX and LTE standards in terms of signal quality and transmitter power efficiency.

  9. Development of high-efficiency wastes-burning electric power generating technology. Volume 2. Report for fiscal 1999; Kokoritsu haikibutsu hatsuden gijutsu kaihatsu 1999 nendo hokokusho. 2

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-03-01

    In high-efficiency power generation using general wastes and combustible industrial wastes as fuel, development has been performed on a wastes gasifying and melting power generation technology. This technology is capable of suppressing generation of dioxines, recovering slag that can be utilized effectively, and reducing ash volume, by thermally decomposing the wastes and melting combustion ash at elevated temperatures by using thermally decomposed gases. With regard to the evaluation on high temperature corrosiveness of SH materials and the development of a high temperature dust removing system, a steam heater was designed, fabricated, and installed in a model plant, wherein the operation test has been performed for about 1,620 hours. For the technology of dechlorination during a thermal decomposition process, dechlorination rate of 90% was confirmed at 425 degrees C or higher in a demonstration plant. In addition, developments were made on a low temperature denitration device to avoid re-heating of waste gases, a stable wastes supply system to reduce quantity of self-heated melt limiting heat generation, and a waste plastics blowing technology to reduce external fuel charge quantity. Furthermore, a survey was carried out on the trends in wastes electric power generation technologies. (NEDO)

  10. High-Bandwidth, High-Efficiency Envelope Tracking Power Supply for 40W RF Power Amplifier Using Paralleled Bandpass Current Sources

    DEFF Research Database (Denmark)

    Høyerby, Mikkel Christian Wendelboe; Andersen, Michael Andreas E.

    2005-01-01

    This paper presents a high-performance power conversion scheme for power supply applications that require very high output voltage slew rates (dV/dt). The concept is to parallel 2 switching bandpass current sources, each optimized for its passband frequency space and the expected load current....... The principle is demonstrated with a power supply, designed for supplying a 40 W linear RF power amplifier for efficient amplification of a 16-QAM modulated data stream...

  11. High efficiency, long life terrestrial solar panel

    Science.gov (United States)

    Chao, T.; Khemthong, S.; Ling, R.; Olah, S.

    1977-01-01

    The design of a high efficiency, long life terrestrial module was completed. It utilized 256 rectangular, high efficiency solar cells to achieve high packing density and electrical output. Tooling for the fabrication of solar cells was in house and evaluation of the cell performance was begun. Based on the power output analysis, the goal of a 13% efficiency module was achievable.

  12. HIGH EFFICIENCY TURBINE

    OpenAIRE

    VARMA, VIJAYA KRUSHNA

    2012-01-01

    Varma designed ultra modern and high efficiency turbines which can use gas, steam or fuels as feed to produce electricity or mechanical work for wide range of usages and applications in industries or at work sites. Varma turbine engines can be used in all types of vehicles. These turbines can also be used in aircraft, ships, battle tanks, dredgers, mining equipment, earth moving machines etc, Salient features of Varma Turbines. 1. Varma turbines are simple in design, easy to manufac...

  13. Development of high-efficiency wastes-burning electric power generating technology. Volume 1. Report for fiscal 1999; Kokoritsu haikibutsu hatsuden gijutsu kaihatsu 1999 nendo hokokusho. 1

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-03-01

    This paper summarizes the achievements of developing a technology to generate electric power at high efficiency by using a combustion furnace that uses general wastes and combustible industrial wastes as fuel to generate high-temperature and high-pressure steam under a stabilized condition. In the developmental research of the combustion furnace, discussions were given on single-pass and double-pass type stalker furnaces, an internal circulation type fluidized bed furnace, and an external circulation type fluidized bed furnace, whereas technological prospects were established on any of them as the combustion furnace. In developing corrosion resistant super heater materials, demonstration tests were performed by using a pilot plant, corrosion mechanisms were elucidated, amount of corrosion in steam generating tubes was discussed, and corrosion life of super heaters was estimated. In developing a technology to reduce environmental load, developmental researches were carried out on a method to treat waste gases by using pulse plasma to have established nearly completely a waste gas treatment system technology. In the demonstration test using the pilot plant, the operation has started from February 1998, generating stably the steam conditions of 500 degrees C and 9.8 MPa, and the smooth operation has continued. (NEDO)

  14. Fabrication of Very High Efficiency 5.8 GHz Power Amplifiers using AlGaN HFETs on SiC Substrates for Wireless Power Transmission

    Science.gov (United States)

    Sullivan, Gerry

    2001-01-01

    For wireless power transmission using microwave energy, very efficient conversion of the DC power into microwave power is extremely important. Class E amplifiers have the attractive feature that they can, in theory, be 100% efficient at converting, DC power to RF power. Aluminum gallium nitride (AlGaN) semiconductor material has many advantageous properties, relative to silicon (Si), gallium arsenide (GaAs), and silicon carbide (SiC), such as a much larger bandgap, and the ability to form AlGaN/GaN heterojunctions. The large bandgap of AlGaN also allows for device operation at higher temperatures than could be tolerated by a smaller bandgap transistor. This could reduce the cooling requirements. While it is unlikely that the AlGaN transistors in a 5.8 GHz class E amplifier can operate efficiently at temperatures in excess of 300 or 400 C, AlGaN based amplifiers could operate at temperatures that are higher than a GaAs or Si based amplifier could tolerate. Under this program, AlGaN microwave power HFETs have been fabricated and characterized. Hybrid class E amplifiers were designed and modeled. Unfortunately, within the time frame of this program, good quality HFETs were not available from either the RSC laboratories or commercially, and so the class E amplifiers were not constructed.

  15. Highly efficient maximum power point tracking using DC-DC coupled inductor single-ended primary inductance converter for photovoltaic power systems

    Science.gov (United States)

    Quamruzzaman, M.; Mohammad, Nur; Matin, M. A.; Alam, M. R.

    2016-10-01

    Solar photovoltaics (PVs) have nonlinear voltage-current characteristics, with a distinct maximum power point (MPP) depending on factors such as solar irradiance and operating temperature. To extract maximum power from the PV array at any environmental condition, DC-DC converters are usually used as MPP trackers. This paper presents the performance analysis of a coupled inductor single-ended primary inductance converter for maximum power point tracking (MPPT) in a PV system. A detailed model of the system has been designed and developed in MATLAB/Simulink. The performance evaluation has been conducted on the basis of stability, current ripple reduction and efficiency at different operating conditions. Simulation results show considerable ripple reduction in the input and output currents of the converter. Both the MPPT and converter efficiencies are significantly improved. The obtained simulation results validate the effectiveness and suitability of the converter model in MPPT and show reasonable agreement with the theoretical analysis.

  16. HIGH EFFICIENCY GENERATION OF HYDROGEN FUELS USING NUCLEAR POWER FINAL RECHNICAL REPORT FOR THE PERIOD AUGUST 1, 1999 THROUGH SEPTEMBER 30, 2002 REV. 1

    Energy Technology Data Exchange (ETDEWEB)

    BROWN,LC; BESENBRUCH,GE; LENTSCH, RD; SCHULTZ,KR; FUNK,JF; PICKARD,PS; MARSHALL,AC; SHOWALTER,SK

    2003-12-01

    carbon monoxide) that are detrimental to precious metal catalyzed fuel cells, as is now recognized by many of the world's largest automobile companies. Thermochemical hydrogen will not contain carbon monoxide as an impurity at any level. Electrolysis, the alternative process for producing hydrogen using nuclear energy, suffers from thermodynamic inefficiencies in both the production of electricity and in electrolytic parts of the process. The efficiency of electrolysis (electricity to hydrogen) is currently about 80%. Electric power generation efficiency would have to exceed 65% (thermal to electrical) for the combined efficiency to exceed the 52% (thermal to hydrogen) calculated for one thermochemical cycle. Thermochemical water-splitting cycles have been studied, at various levels of effort, for the past 35 years. They were extensively studied in the late 70s and early 80s but have received little attention in the past 10 years, particularly in the U.S. While there is no question about the technical feasibility and the potential for high efficiency, cycles with proven low cost and high efficiency have yet to be developed commercially. Over 100 cycles have been proposed, but substantial research has been executed on only a few. This report describes work accomplished during a three-year project whose objective is to ''define an economically feasible concept for production of hydrogen, by nuclear means, using an advanced high temperature nuclear reactor as the energy source.''

  17. F-band, High-Efficiency GaN Power Amplifier for the Scanning Microwave Limb Sounder and SOFIA, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — QuinStar Technology proposes to develop a high-efficiency, 4-W SSPA operating at F-band frequencies (106-114 GHz). This will be achieved by employing two major...

  18. High-efficiency CARM

    Energy Technology Data Exchange (ETDEWEB)

    Bratman, V.L.; Kol`chugin, B.D.; Samsonov, S.V.; Volkov, A.B. [Institute of Applied Physics, Nizhny Novgorod (Russian Federation)

    1995-12-31

    The Cyclotron Autoresonance Maser (CARM) is a well-known variety of FEMs. Unlike the ubitron in which electrons move in a periodical undulator field, in the CARM the particles move along helical trajectories in a uniform magnetic field. Since it is much simpler to generate strong homogeneous magnetic fields than periodical ones for a relatively low electron energy ({Brit_pounds}{le}1-3 MeV) the period of particles` trajectories in the CARM can be sufficiently smaller than in the undulator in which, moreover, the field decreases rapidly in the transverse direction. In spite of this evident advantage, the number of papers on CARM is an order less than on ubitron, which is apparently caused by the low (not more than 10 %) CARM efficiency in experiments. At the same time, ubitrons operating in two rather complicated regimes-trapping and adiabatic deceleration of particles and combined undulator and reversed guiding fields - yielded efficiencies of 34 % and 27 %, respectively. The aim of this work is to demonstrate that high efficiency can be reached even for a simplest version of the CARM. In order to reduce sensitivity to an axial velocity spread of particles, a short interaction length where electrons underwent only 4-5 cyclotron oscillations was used in this work. Like experiments, a narrow anode outlet of a field-emission electron gun cut out the {open_quotes}most rectilinear{close_quotes} near-axis part of the electron beam. Additionally, magnetic field of a small correcting coil compensated spurious electron oscillations pumped by the anode aperture. A kicker in the form of a sloping to the axis frame with current provided a control value of rotary velocity at a small additional velocity spread. A simple cavity consisting of a cylindrical waveguide section restricted by a cut-off waveguide on the cathode side and by a Bragg reflector on the collector side was used as the CARM-oscillator microwave system.

  19. F-band, High-Efficiency GaN Power Amplifier for the Scanning Microwave Limb Sounder and SOFIA, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — QuinStar Technology proposes to develop a 4-watt Solid-State Power Amplifier (SSPA) operating at F-band (106-114 GHz) with a power-added efficiency (PAE) of greater...

  20. Research and development of photovoltaic power system. Research on surface passivation for high-efficiency silicon solar cells; Taiyoko hatsuden system no kenkyu kaihatsu. Hyomen passivation no kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Saito, T [Tokyo Univ. of Agriculture and Technology, Tokyo (Japan). Faculty of Technology

    1994-12-01

    This paper reports the result obtained during fiscal 1994 on research on surface passivation of high-efficiency silicon solar cells. In research on carrier recombination on SiO2/doped silicon interface, measurements were carried out on minority carrier life with respect to p-type silicon substrates with which phosphorus with high and low concentrations are diffused uniformly on the surface and non-uniformly on the back and then oxidized. The measurements were performed for the purpose of evaluating the carrier recombination at p-n junctions. Effective life time of oxidized test samples increased longer than that of prior to the oxidization as a result of effect of surface passivation contributing remarkably. In research on reduction in carrier recombination on SiO2/Si interface by using H radical annealing, experiments were conducted by using a method that uses more active H-atoms. As a result, it was revealed that the reduction effect is recognized at as low temperature as 200{degree}C, and photo-bias effect is also noticeable. Other research activities included analytic research on minority carrier recombination on micro crystalline silicon/crystalline silicon interface, and experimental research on evaluation of minority carrier life of poly-crystalline silicon wafers. 6 figs.

  1. High-power and highly efficient diode-cladding-pumped holmium-doped fluoride fiber laser operating at 2.94 microm.

    Science.gov (United States)

    Jackson, Stuart D

    2009-08-01

    A high-power diode-cladding-pumped Ho(3+), Pr(3+)-doped fluoride glass fiber laser is demonstrated. The laser produced a maximum output power of 2.5 W at a slope efficiency of 32% using diode lasers emitting at 1,150 nm. The long-emission wavelength of 2.94 microm measured at maximum pump power, which is particularly suited to medical applications, indicates that tailoring of the proportion of Pr(3+) ions can provide specific emission wavelengths while providing sufficient de-excitation of the lower laser level.

  2. Coal gasification integration with solid oxide fuel cell and chemical looping combustion for high-efficiency power generation with inherent CO2 capture

    International Nuclear Information System (INIS)

    Chen, Shiyi; Lior, Noam; Xiang, Wenguo

    2015-01-01

    Highlights: • A novel power system integrating coal gasification with SOFC and chemical looping combustion. • The plant net power efficiency reaches 49.8% with complete CO 2 separation. • Energy and exergy analysis of the entire plant is conducted. • Sensitivity analysis shows a nearly constant power output when SOFC temperature and pressure vary. • NiO oxygen carrier shows higher plant efficiency than using Fe 2 O 3 and CuO. - Abstract: Since solid oxide fuel cells (SOFC) produce electricity with high energy conversion efficiency, and chemical looping combustion (CLC) is a process for fuel conversion with inherent CO 2 separation, a novel combined cycle integrating coal gasification, solid oxide fuel cell, and chemical looping combustion was configured and analyzed. A thermodynamic analysis based on energy and exergy was performed to investigate the performance of the integrated system and its sensitivity to major operating parameters. The major findings include that (1) the plant net power efficiency reaches 49.8% with ∼100% CO 2 capture for SOFC at 900 °C, 15 bar, fuel utilization factor = 0.85, fuel reactor temperature = 900 °C and air reactor temperature = 950 °C, using NiO as the oxygen carrier in the CLC unit. (2) In this parameter neighborhood the fuel utilization factor, the SOFC temperature and SOFC pressure have small effects on the plant net power efficiency because changes in pressure and temperature that increase the power generation by the SOFC tend to decrease the power generation by the gas turbine and steam cycle, and v.v.; an advantage of this system characteristic is that it maintains a nearly constant power output even when the temperature and pressure vary. (3) The largest exergy loss is in the gasification process, followed by those in the CO 2 compression and the SOFC. (4) Compared with the CLC Fe 2 O 3 and CuO oxygen carriers, NiO results in higher plant net power efficiency. To the authors’ knowledge, this is the first

  3. Design Method for the Coil-System and the Soft Switching Technology for High-Frequency and High-Efficiency Wireless Power Transfer Systems

    Directory of Open Access Journals (Sweden)

    Xu Liu

    2017-12-01

    Full Text Available Increasing the resonant frequency of a wireless power transfer (WPT system effectively improves the power transfer efficiency between the transmit and the receive coils but significantly limits the power transfer capacity with the same coils. Therefore, this paper proposes a coil design method for a series-series (SS compensated WPT system which can power up the same load with the same DC input voltage & current but with increased resonant frequency. For WPT systems with higher resonant frequencies, a new method of realizing soft-switching by tuning driving frequency is proposed which does not need to change any hardware in the WPT system and can effectively reduce switching losses generated in the inverter. Eighty-five kHz, 200 kHz and 500 kHz WPT systems are built up to validate the proposed methods. Experimental results show that all these three WPT systems can deliver around 3.3 kW power to the same load (15 Ω with 200 V input voltage and 20 A input current as expected and achieve more than 85% coil-system efficiency and 79% system overall efficiency. With the soft-switching technique, inverter efficiency can be improved from 81.91% to 98.60% in the 500 kHz WPT system.

  4. Fiscal 2000 report on the development of high-efficiency refuse-fueled power generation technology; Kokoritsu haikibutsu hatsuden gijutsu kaihatsu 2000 nendo hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-03-01

    Efforts were made to develop a refuse gasification/fusion power generation technology to contribute to the effective utilization of unexploited energy and to reduction in greenhouse gas emissions. Developed in the technology of elevating steam temperature were the evaluation of high-temperature corrosion of SH materials and a high temperature dust removing system, dechlorination technology for the thermolysis process, and a ceramic-made high-temperature air heater. For the avoidance of exhaust gas reheating, development was carried out for a low-temperature denitration unit, stable refuse feeding system for reduction in the self-heat melting critical calorific value, waste plastic injection technology for reduction in the amount of external fuel injection, and so forth. The effect of the developed element technologies were evaluated and a detailed feasibility study was conducted for a refuse gas conversion power generation system using gas engine power generation for minor-scale general waste treatment facilities. In the survey of the trend of refuse-fueled power generation technologies, trend in Japan and advanced refuse-fueled power generation systems and their introduction in Europe and America were investigated. (NEDO)

  5. High-Power and High-Efficiency 1.3- µm Superluminescent Diode With Flat-Top and Ultrawide Emission Bandwidth

    KAUST Repository

    Khan, Mohammed Zahed Mustafa; Alhashim, Hala H.; Ng, Tien Khee; Ooi, Boon S.

    2015-01-01

    We report on a flat-top and ultrawide emission bandwidth of 125 nm from InGaAsP/InP multiple quantum-well (MQW) superluminescent diode with antireflection coated and tilted ridge-waveguide device configuration. A total output power in excess of 70 mW with an average power spectral density of 0.56 mW/nm and spectral ripple ≤ 1.2 ± 0.5 dB is measured from the device. Wall-plug efficiency and output power as high as 14% and 80 mW, respectively, is demonstrated from this batch of devices. We attribute the broad emission to the inherent inhomogeneity of the electron-heavy-hole (e-hh) and electron-light-hole (e-lh) recombination of the ground state and the first excited state of the MQWs and their simultaneous emission.

  6. High-Power and High-Efficiency 1.3- µm Superluminescent Diode With Flat-Top and Ultrawide Emission Bandwidth

    KAUST Repository

    Khan, Mohammed Zahed Mustafa

    2015-02-01

    We report on a flat-top and ultrawide emission bandwidth of 125 nm from InGaAsP/InP multiple quantum-well (MQW) superluminescent diode with antireflection coated and tilted ridge-waveguide device configuration. A total output power in excess of 70 mW with an average power spectral density of 0.56 mW/nm and spectral ripple ≤ 1.2 ± 0.5 dB is measured from the device. Wall-plug efficiency and output power as high as 14% and 80 mW, respectively, is demonstrated from this batch of devices. We attribute the broad emission to the inherent inhomogeneity of the electron-heavy-hole (e-hh) and electron-light-hole (e-lh) recombination of the ground state and the first excited state of the MQWs and their simultaneous emission.

  7. Channel Temperature Model for Microwave AlGaN/GaN HEMTs on SiC and Sapphire MMICs in High Power, High Efficiency SSPAs

    Science.gov (United States)

    Freeman, Jon C.

    2004-01-01

    A key parameter in the design trade-offs made during AlGaN/GaN HEMTs development for microwave power amplifiers is the channel temperature. An accurate determination can, in general, only be found using detailed software; however, a quick estimate is always helpful, as it speeds up the design cycle. This paper gives a simple technique to estimate the channel temperature of a generic microwave AlGaN/GaN HEMT on SiC or Sapphire, while incorporating the temperature dependence of the thermal conductivity. The procedure is validated by comparing its predictions with the experimentally measured temperatures in microwave devices presented in three recently published articles. The model predicts the temperature to within 5 to 10 percent of the true average channel temperature. The calculation strategy is extended to determine device temperature in power combining MMICs for solid-state power amplifiers (SSPAs).

  8. Thermodynamic and economic studies of two new high efficient power-cooling cogeneration systems based on Kalina and absorption refrigeration cycles

    International Nuclear Information System (INIS)

    Rashidi, Jouan; Ifaei, Pouya; Esfahani, Iman Janghorban; Ataei, Abtin; Yoo, Chang Kyoo

    2016-01-01

    Highlights: • Proposing two new power and cooling cogeneration systems based on absorption chillers and Kalina cycles. • Model-based comparison through thermodynamic and economic standpoints. • Investigating sensitivity of system performance and costs to the key parameters. • Reducing total annual costs of the base system up to 8% by cogeneration. • Increasing thermal efficiency up to 4.9% despite of cooling generation. - Abstract: Two new power and cooling cogeneration systems based on Kalina cycle (KC) and absorption refrigeration cycle (AC) are proposed and studied from thermodynamic and economic viewpoints. The first proposed system, Kalina power-cooling cycle (KPCC), combines the refrigerant loop of the water-ammonia absorption chiller, consisting of an evaporator and two throttling valves with the KC. A portion of the KC mass flow enters the evaporator to generate cooling after being condensed in the KPCC system. KPCC is a flexible system adapting power and cooling cogeneration to the demand. The second proposed system, Kalina lithium bromide absorption chiller cycle (KLACC), consists of the KC and a single effect lithium bromide-water absorption chiller (AC_L_i_B_r_-_w_a_t_e_r). The KC subsystem discharges heat to the AC_L_i_B_r_-_w_a_t_e_r desorber before condensing in the condenser. The performance and economic aspects of both proposed systems are analyzed and compared with the stand alone KC. A parametric analysis is conducted to evaluate the sensitivity of efficiencies and the generated power and cooling quantities to the key operating variables. The results showed that, thermal efficiency and total annual costs decreased by 5.6% and 8% for KPCC system but increased 4.9% and 58% for KLACC system, respectively. Since the power-cooling efficiency of KLACC is 42% higher than KPCC it can be applied where the aim is cooling generation without considering economic aspects.

  9. The rewritable effects of bonded magnet for large starting torque and high efficiency in the small power single-phase written pole motor

    Science.gov (United States)

    Choi, Jae-Hak; Lee, Sung-Ho

    2009-04-01

    This paper presents a single-phase written pole motor using a bonded ring magnet for the small power home application. The motor has an exciter pole structure inside the stator and hybrid characteristics of an induction motor and permanent magnet motor. The design parameters and operating characteristics of the hybrid concept motor are investigated to increase starting torque and efficiency, which is most important for the small power home application. Larger starting torque and higher efficiency than those of the conventional induction motor could be obtained by using the rewritable characteristics of bonded magnet on the starting and running conditions.

  10. High-gain (43 dB), high-power (40 W), highly efficient multipass amplifier at 995 nm in Yb:LiYF4

    Science.gov (United States)

    Manni, Jeffrey; Harris, Dennis; Fan, Tso Yee

    2018-06-01

    A simple implementation of a multipass amplifier along with the use of a cryogenic Yb:LiYF4 (YLF) gain medium has enabled the demonstration of a bulk amplifier with an unprecedented combination of large-signal gain (43 dB), efficiency (>50% optical), average output power (40 W) and a near-diffraction-limited output beam.

  11. Integration of solid oxide fuel cell (SOFC) and chemical looping combustion (CLC) for ultra-high efficiency power generation and CO2 production

    NARCIS (Netherlands)

    Spallina, Vincenzo; Nocerino, Pasquale; Romano, Matteo C.; van Sint Annaland, Martin; Campanari, Stefano; Gallucci, Fausto

    2018-01-01

    This work presents a thermodynamic analysis of the integration of solid oxide fuel cells (SOFCs) with chemical looping combustion (CLC) in natural gas power plants. The fundamental idea of the proposed process integration is to use a dual fluidized-bed CLC process to complete the oxidation of the

  12. Survey on the feasibility of high-efficiency gas turbine power generation system; Kokoritsu gas turbine hatsuden system ni kansuru jitsuyo kanosei chosa

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    For higher-efficiency power generation cycle plants with less restrained conditions for a location, the conceptual design of an inter-cooled regenerative two-fluid cycle plant (ISTIG) was attempted using a modified aircraft gas turbine. A high-performance turbo fan engine is used for middle-class power generation. The first stage combustion gas drives the first stage turbine, and its exhaust gas is used for the second stage combustion. Because of two-axial type of high and low pressure, improvement of thermal efficiency is expected by easy-to-install inter-cooler. ISTIG superior in operability is suitable for medium load or distributed power generation facilities, and aims at higher efficiency of a 60% level. ISTIG includes a large amount of water vapor in combustion air by adopting a diffusion type combustor eliminating back fire, and can reduce exergy loss by preheating fuel gas. Since load of the high-pressure turbine shifts toward low-pressure one by the inter-cooler, some considerations are necessary for low-pressure side cooling together with reheating cycle. Because of unnecessary steam turbine, the construction cost per kW can be reduced by 20%. 41 refs., 64 figs., 27 tabs.

  13. Commissioning and operating experiences with high-efficiency, environmentally acceptable brown coal thermal power units; Inbetriebsetzung und Betriebserfahrungen mit hoch effizienten und umweltfreundlichen Braunkohlebloecken

    Energy Technology Data Exchange (ETDEWEB)

    Kehr, M.; Mandel, H.; Kather, A.

    1998-12-31

    The generation system of VEAG had a power output 15,000 MW, of which 82%, or 12,700 MW, came from brown coal power plants that had no flue gas desulphurisation and insufficient flue gas dedusting facilities. One of the major goals of the company`s programme for enhancing the economic efficiency and public acceptance of the conversion of brown coal to electricity was to achieve a net power plant efficiency of 40%. In the case of the ``KW Schwarze Pumpe`` project this was achieved by the use of supercritical steam parameters, installation of a flue gas heat recovery system, and the optimisation of the cold end of the turbine by allowing for a condenser pressure of 40 mbar and by connecting condensers in series. Further effects were achieved by fine adjustments to the thermal circuitry. [Deutsch] Der Kraftwerkspark der VEAG umfasste 15.400 MW und bestand mit 12.700 MW zu 82% aus Braunkohlekraftwerken, die ueber keine Rauchgasentschwefelung und unzureichende Entstaubungsanlagen im Rauchgas verfuegten. Als wesentliche Forderung zur Erhoehung der Wirtschaftlichkeit und Akzeptanz der Braunkohleverstromung wurde die Forderung nach Erreichen eines Netto-Kraftwerkswirkungsgrades von 40% gestellt. Fuer das Projekt KW Schwarze Pumpe wurde neben der Anwendung der ueberkritschen Dampfparameter zur Sicherung der Zielstellung eines Wirkungsgrades von mindestens 40% der Einbau einer Rauchgaswaermenutzung und die Optimierung des kalten Endes der Turbine mit Auslegung fuer einen Kondensatordruck von 40 mbar sowie Reihenschaltung der Kondensatoren festgelegt. Weitere Effekte wurden durch Feinoptimierung des Waermeschaltbildes erreicht. (orig.)

  14. Flexible one-structure arched triboelectric nanogenerator based on common electrode for high efficiency energy harvesting and self-powered motion sensing

    Science.gov (United States)

    Chen, Xi; He, Jian; Song, Linlin; Zhang, Zengxing; Tian, Zhumei; Wen, Tao; Zhai, Cong; Chen, Yi; Cho, Jundong; Chou, Xiujian; Xue, Chenyang

    2018-04-01

    Triboelectric nanogenerators are widely used because of low cost, simple manufacturing process and high output performance. In this work, a flexible one-structure arched triboelectric nanogenerator (FOAT), based on common electrode to combine the single-electrode mode and contact-separation, was designed using silicone rubber, epoxy resin and flexible electrode. The peak-to-peak short circuit current of 18μ A and the peak-to-peak open circuit voltage of 570V can be obtained from the FOAT with the size of 5×7 cm2 under the frequency of 3Hz and the pressure of 300N. The peak-to-peak short circuit current of FOAT is increased by 29% and 80%, and the peak-to-peak open circuit voltage is increased by 33% and 54% compared with single-electrode mode and contact-separation mode, respectively. FOAT realizes the combination of two generation modes, which improves the output performance of triboelectric nanogenerator (TENG). 62 light-emitting-diodes (LEDs) can be completely lit up and 2.2μ F capacitor can be easily charged to 1.2V in 9s. When the FOAT is placed at different parts of the human body, the human motion energy can be harvested and be the sensing signal for motion monitoring sensor. Based on the above characteristics, FOAT exhibits great potential in illumination, power supplies for wearable electronic devices and self-powered motion monitoring sensor via harvesting the energy of human motion.

  15. Study of highly efficient power generation system based on chemical-looping combustion; Chemical loop nenshoho ni yoru kokoritsu hatsuden system no kaihatsu ni kansuru kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Ishida, S; Suzuki, T; Yamamoto, M [Tokyo Institute of Technology, Tokyo (Japan). Research Laboratory of Resources Utilization

    1997-02-01

    This paper describes the research and development of power generation system by means of chemical-looping combustion. For this system, fuel flows in a reduction reactor and air flows in an oxidation reactor. These two flows are separated. As a result, recovery of CO2 without energy consumption, drastic improvement of power generation efficiency, and suppression of NOx emission are expected. To realize the above, two promising candidates, NiCoO2/YSZ and NiO2/NiAl2O4, have been found as recycle solid particles between the both reactors. These have excellent oxidation/reduction cycle characteristics. By these particles as well as the existing particle, NiO/YSZ, practical application of the chemical-looping combustion is realized. Besides LNG, coal and hydrogen were considered as fuels. When using coal or hydrogen, it was found that temperature of the reduction reactor should be increased the same as that of the oxidation reactor. This is a different point from a case using LNG as a fuel. 5 refs., 2 figs.

  16. Development of technologies on innovative-simplified nuclear power plant using high-efficiency steam injectors (8) numerical simulation using SOROBAN-grid CIP method

    International Nuclear Information System (INIS)

    Yasutaka Sakurai; Takashi Yabe; Tomomasa Ohkubo; Yoichi Ogata; Michitsugu Mori

    2005-01-01

    Generally, there are two coordinate systems in computation of fluid dynamics: curvilinear coordinate or Cartesian coordinate. The former is suitable for describing complex figure, but it cannot get high accuracy. On the other hand, the latter can easily increase the accuracy, but it needs a large number of grids to describe complex figure. In this paper, we propose a new grid generating method, the Soroban grid, which has large capability for treating complex figure and does not lose the accuracy. Coupling this grid generating method and the CIP method, we can get flexibility to describe complex figure without loosing (3rd order) accuracy. Since the Soroban grid is unstructured grid, we can not use the staggered grid and had better use the co-location grid. Although the fluid computation in the co-location grid is usually unstable, we succeeded in calculating the multi-phase flow that has large density difference applying the C-CUP method to this grid system. In this paper, we shall introduce this grid generating method and apply these methods to simulate the steam injector of power plant. (authors)

  17. Design of High-Efficiency and Low-Cost Six-Phase Permanent Magnet Synchronous Generator for Direct-Drive Small-Scale Wind Power Application

    Directory of Open Access Journals (Sweden)

    M. E. Moazzen

    2017-06-01

    Full Text Available Permanent magnet synchronous generators (PMSG have a huge potential for direct-drive wind power applications. Therefore, optimal design of these generators is necessary to maximize their efficiency and to reduce their manufacturing cost and total volume. In this paper, an optimal design of a six-phase 3.5 KW direct-drive PMSG to generate electricity for domestic needs is performed. The aim of optimal design is to reduce the manufacturing cost, losses and total volume of PMSG. To find the best design, single/multi-objective design optimization is carried out. Cuckoo optimization algorithm (COA is adopted to solve the optimization problem. Comparison between the results of the single-objective and multi-objective models shows that simultaneous optimization of manufacturing cost, losses and total volume leads to more suitable design for PMSG. Finally, finite-element method (FEM is employed to validate the optimal design, which show a good agreement between the theoretical work and simulation results.

  18. Development of technologies on innovative-simplified nuclear power plant using high-efficiency steam injectors. (6) Operating characteristics of center water jet type supersonic steam injector

    International Nuclear Information System (INIS)

    Kawamoto, Yujiro; Abe, Yutaka; Iwaki, Chikako; Narabayashi, Tadashi; Mori, Michitsugu; Ohmori, Shuichi

    2004-01-01

    One of the most interesting devices for next generation reactor systems aiming at simplified system and improvement of safety and credibility is the steam injector which is a passive pump without large motor or turbo-machinery. One of the applications of the steam injector is the passive water injection system to inject the coolant water into the core. The system can be started up merely by injecting the steam without any outer power supply. Since the steam injector is a simple, compact and passive device for water injection, if the steam injector is applied to the actual reactor, it is expected to make the system simple and to reduce the construction cost. Although non-condensable gases are well known for reducing heat transfer between water and steam, the effect of the non-condensable gas on the condensation of supersonic steam on high-speed water jet has not been cleared. The present paper reports about the experimental apparatus, measurement instrument and experimental results of observing the phenomenon inside the test section supplying water and steam to the test by using both the high-speed camera and the video camera and measuring the temperature and the pressure distribution n the test section. (author)

  19. Unconventional, High-Efficiency Propulsors

    DEFF Research Database (Denmark)

    Andersen, Poul

    1996-01-01

    The development of ship propellers has generally been characterized by search for propellers with as high efficiency as possible and at the same time low noise and vibration levels and little or no cavitation. This search has lead to unconventional propulsors, like vane-wheel propulsors, contra-r...

  20. High efficiency inverter and ballast circuits

    International Nuclear Information System (INIS)

    Nilssen, O.K.

    1984-01-01

    A high efficiency push-pull inverter circuit employing a pair of relatively high power switching transistors is described. The switching on and off of the transistors is precisely controlled to minimize power losses due to common-mode conduction or due to transient conditions that occur in the process of turning a transistor on or off. Two current feed-back transformers are employed in the transistor base drives; one being saturable for providing a positive feedback, and the other being non-saturable for providing a subtractive feedback

  1. Fiscal 1997 report of the development of high efficiency waste power generation technology. No.1 volume. Element technology development; Kokoritsu haikibutsu hatsuden gijutsu kaihatsu (yoso gijutsu kaihatsu). 1997 nendo hokokusho (daiichi bunsatsu)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-01

    Following the previous fiscal year, the technology development was conducted of a high efficiency waste power generation system using general waste as fuel. In the development of high temperature high efficiency combustion furnace, a combustion test on the external circulating fluidized bed incinerator was made to obtain data on formation/decomposition of dioxins. Moreover, a combustion test was conducted using mock refuse, petroleum-derived waste and waste plastics, to confirm stabilized combustion characteristics and low pollution. In the development of a corrosion resistant superheater, made were the stress load high temperature corrosion test, study of intergranular corrosion by elements of impurities, etc. In the development of the environmental load reduction technology, conducted was the conceptional design of pulse plasma exhaust gas disposal equipment corresponding to the actual one. In the verification test in a pilot plant, the pilot plant passed the pre-use inspection and was completed in February 1998. In the study of an optimal total system, discussed were the data on the pilot plant verification test, measuring points, how to arrange them, etc. 2 refs., 88 figs., 50 tabs.

  2. Overview of Ecological Agriculture with High Efficiency

    OpenAIRE

    Huang, Guo-qin; Zhao, Qi-guo; Gong, Shao-lin; Shi, Qing-hua

    2012-01-01

    From the presentation, connotation, characteristics, principles, pattern, and technologies of ecological agriculture with high efficiency, we conduct comprehensive and systematic analysis and discussion of the theoretical and practical progress of ecological agriculture with high efficiency. (i) Ecological agriculture with high efficiency was first advanced in China in 1991. (ii) Ecological agriculture with high efficiency highlights "high efficiency", "ecology", and "combination". (iii) Ecol...

  3. Fiscal 2000 achievement report on the followup research on high-efficiency refuse-fueled power generation technology development; 2000 nendo kokoritsu haikibutsu hatsuden gijutsu kaihatsu no follow up kenkyu seika hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-03-01

    Followup research was conducted using a high-efficiency refuse-fueled power generation pilot plant for interpolating research and development results, improvement on refuse-fueled power generation efficiency, and for introduction and popularization of refuse-fueled power generation. Operation control and safety control were performed in compliance with the pilot plant operation program, when high-temperature high-pressure steam (500 degrees C, 100 atm) was stably generated for approximately 7,600 hours in this fiscal year recording a total of approximately 22,000 hours when counted from the beginning of the verification test. Plant operation data were examined and every part of the furnace was checked and measured while the furnace was at rest, and it was found that the plant satisfied the intended specifications as refuse-fueled power plant facilities. As for its environmental impact, it was confirmed that it fully satisfied the standard values for substances in exhaust gas, which involved soot and dust, sulfur oxides, nitrogen oxides, hydrogen chloride, and dioxins. Dioxins, in particular, were far below the most rigorous legal level of 0.1ng-TEQ/m{sup 3}N. In the test of superheater materials, long-term data covering three years were acquired. (NEDO)

  4. Designing high efficient solar powered lighting systems

    DEFF Research Database (Denmark)

    Poulsen, Peter Behrensdorff; Thorsteinsson, Sune; Lindén, Johannes

    2016-01-01

    Some major challenges in the development of L2L products is the lack of efficient converter electronics, modelling tools for dimensioning and furthermore, characterization facilities to support the successful development of the products. We report the development of 2 Three-Port-Converters respec...

  5. Design of High Efficient MPPT Solar Inverter

    Directory of Open Access Journals (Sweden)

    Sunitha K. A.

    2017-01-01

    Full Text Available This work aims to design a High Efficient Maximum Power Point Tracking (MPPT Solar Inverter. A boost converter is designed in the system to boost the power from the photovoltaic panel. By this experimental setup a room consisting of 500 Watts load (eight fluorescent tubes is completely controlled. It is aimed to decrease the maintenance cost. A microcontroller is introduced for tracking the P&O (Perturb and Observe algorithm used for tracking the maximum power point. The duty cycle for the operation of the boost convertor is optimally adjusted by using MPPT controller. There is a MPPT charge controller to charge the battery as well as fed to inverter which runs the load. Both the P&O scheme with the fixed variation for the reference current and the intelligent MPPT algorithm were able to identify the global Maximum power point, however the performance of the MPPT algorithm was better.

  6. FY 2000 report on the results of development of technology for commercializing high-efficiency fuel cell systems. Development of technology for commercializing high-efficiency fuel cell systems (Development of technology for effective utilization of power produced by polymer electrolyte fuel cell systems); 2000 nendo kokoritsu nenryo denchi system jitsuyoka gijutsu kaihatsu seika hokokusho. Kotai kobunshigata nenryo denchi no shutsuryoku yuko riyo gijutsu kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-03-01

    This project is aimed at development of technologies for effective utilization of power produced by polymer electrolyte fuel cell (PEFC) systems and waste heat, to spread cogeneration systems incorporating PEFC systems for residential purposes. Described herein are the FY 2000 results. The program for high-efficiency peripherals for residential PFEC systems attempts use of GaN-FET as the semiconductor device of wide band gap and high breakdown voltage to realize conversion efficiency over 90% by improving inverter efficiency. Two types of the prototype heat recovery systems are developed for the PEFC, one incorporating a latent heat cooling system and the other a water cooling system, to improve heat recovery efficiency and increase heat recovery temperature. The program for technology to fit PEFC output to energy demand develops hot water supply systems provided with a hot water storage function for stable supply of hot water irrespective of the heat recovery conditions, and also with a back-up function with burners. The program also develops the PEFC system of fine load following characteristics, for which pure hydrogen is used as the fuel to allow the system to instantaneously follow fluctuating loads. The program for high-efficiency partial load operation technology studies a 1kW-class residential PEFC cogeneration system incorporating a power storage device for high-efficiency operation at partial loads, where the former operates in a high output mode while the latter absorbs fluctuating loads. (NEDO)

  7. Fiscal 1997 report of the development of high efficiency waste power generation technology. No.2 volume. Pilot plant verification test; Kokoritsu haikibutsu hatsuden gijutsu kaihatsu (pilot plant jissho shiken). 1997 nendo hokokusho (daini bunsatsu)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-01

    As to a high efficiency waste power generation system using general waste as fuel, the details of the following were described: design/construction management and operational study of pilot plant, design/manufacture/construction of pilot plant, and study of an optimal total system. Concerning the construction management and operational study, the paper described the application for governmental/official inspection procedures and taking inspection, process management of pilot plant, site patrol, safety management, management of trial run of pilot plant, drawing-up of a verification test plan and test run, etc. Relating to the design/manufacture/construction of pilot plant, an outline of the pilot plant was described. The paper also stated points to be considered in design of furnace structure and boiler structure, points to be considered of the verification test, etc. As to the study of an optimal total system, the following were described: survey of waste gasification/slagging power generation technology, basic study on RDF production process, survey of trends of waste power generation technology in the U.S., etc. 52 refs., 149 figs., 121 tabs.

  8. High Efficiency Room Air Conditioner

    Energy Technology Data Exchange (ETDEWEB)

    Bansal, Pradeep [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-01-01

    This project was undertaken as a CRADA project between UT-Battelle and Geberal Electric Company and was funded by Department of Energy to design and develop of a high efficiency room air conditioner. A number of novel elements were investigated to improve the energy efficiency of a state-of-the-art WAC with base capacity of 10,000 BTU/h. One of the major modifications was made by downgrading its capacity from 10,000 BTU/hr to 8,000 BTU/hr by replacing the original compressor with a lower capacity (8,000 BTU/hr) but high efficiency compressor having an EER of 9.7 as compared with 9.3 of the original compressor. However, all heat exchangers from the original unit were retained to provide higher EER. The other subsequent major modifications included- (i) the AC fan motor was replaced by a brushless high efficiency ECM motor along with its fan housing, (ii) the capillary tube was replaced with a needle valve to better control the refrigerant flow and refrigerant set points, and (iii) the unit was tested with a drop-in environmentally friendly binary mixture of R32 (90% molar concentration)/R125 (10% molar concentration). The WAC was tested in the environmental chambers at ORNL as per the design rating conditions of AHAM/ASHRAE (Outdoor- 95F and 40%RH, Indoor- 80F, 51.5%RH). All these modifications resulted in enhancing the EER of the WAC by up to 25%.

  9. High-efficient electron linacs

    International Nuclear Information System (INIS)

    Glavatskikh, K.V.; Zverev, B.V.; Kalyuzhnyj, V.E.; Morozov, V.L.; Nikolaev, S.V.; Plotnikov, S.N.; Sobenin, N.P.; Vovna, V.A.; Gryzlov, A.V.

    1993-01-01

    Comparison analysis of ELA on running and still waves designed for 10 MeV energy and with high efficiency is carried out. It is shown, that from the point of view of dimensions ELA with a still wave or that of a combined type is more preferable. From the point of view of impedance characteristics in any variant with application of magnetron as HF-generator it is necessary to implement special requirements to the accelerating structure if no ferrite isolation is provided in HF-channel. 3 refs., 4 figs., 1 tab

  10. FY1995 study of highly efficient power generation system based on chemical-looping combustion; 1995 nendo chemical loop nenshoho ni yoru kokoritsu hatsuden system no kaihatsu ni kansuru kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    Synthesis of highly efficient and low emission power generation plant with chemical-looping combustion using various fuels such as natural gas, coal gas and hydrogen. Development of new looping materials with suitable reactivity, regenerative ability, and avoidance of carbon deposition. To obtain the design data for demo-plant by using the current experiment high- pressure fixed bed reactor. From the viewpoint of application of the proposed power generation system with chemical-looping combustion, the following main results were obtained. 1. New looping materials: NiO/NiAl{sub 2}O{sub 4}, CoO-NiO/YSZ, and Co{sub 3}O{sub 4}/CoAl{sub 2}O{sub 4}. These materials have high reactivity, repeatability, and avoidance of carbon deposition which play important roles in application of this new combustor. 2. NO{sub x} formation can be completely avoided; both fuel NO{sub x} in reduction reactor for coal gas as fuel and thermal NO{sub x} in oxidation reactor. 3. It is identified from the experiment using fixed bed reactor with the elevated pressure that NiO/NiAl{sub 2}O{sub 4} is a suitable material for coal gas or hydrogen. These promising results have provided valuable data for industrial application. (NEDO)

  11. Analysis and evaluation for practical application of photovoltaic power generation system. Analysis and evaluation for development of extra-high efficiency solar cells (fundamental research on extra-high efficiency Si solar cells); Taiyoko hatsuden system jitsuyoka no tame no kaiseki hyoka. Chokokoritsu taiyo denchi no gijutsu kaihatsu no tame no kaiseki hyoka (chokokoritsu silicon taiyo denchi gijutsu kaihatsu)

    Energy Technology Data Exchange (ETDEWEB)

    Sekikawa, T; Suzuki, E; Ishikawa, K; Takato, H; Yui, N; Shimokawa, R [Electrotechnical Laboratory, Tsukuba (Japan)

    1994-12-01

    Described herein are the results of the FY1994 research program for analysis and evaluation for development of extra-high efficiency silicon solar cells. It is necessary for development of extra-high efficiency Si solar cells to extend as far as possible service life of minority carriers and to develop the evaluation techniques. Noting photoluminescence (PL) observable even with Si, the method of evaluating characteristics of minority carriers, which are not limited in samples, is developed to experimentally determine their service life from transitional response of the PL characteristics. Si has an extremely low quantum effect, because it is an indirect transitional semiconductor, and needs measurement of very high sensitivity. A rapid heat annealing apparatus and others to generate carriers in the infrared and ultraviolet regions are provided in consideration that these are possible means to increase efficiency. These possibilities will be pursued by developing the annealing techniques. 1 fig.

  12. Highly efficient pulsed power supply system with a two-stage LC generator and a step-up transformer for fast capillary discharge soft x-ray laser at shorter wavelength

    International Nuclear Information System (INIS)

    Sakai, Yusuke; Takahashi, Shnsuke; Komatsu, Takanori; Song, Inho; Watanabe, Masato; Hotta, Eiki

    2010-01-01

    Highly efficient and compact pulsed power supply system for a capillary discharge soft x-ray laser (SXRL) has been developed. The system consists of a 2.2 μF two-stage LC inversion generator, a 2:54 step-up transformer, a 3 nF water capacitor, and a discharge section with a few tens of centimeter length capillary. Adoption of the pulsed transformer in combination with the LC inversion generator enables us to use only one gap switch in the circuit for charging the water capacitor up to about 0.5 MV. Furthermore, step-up ratio of a water capacitor voltage to a LC inversion generator initial charging voltage is about 40 with energy transfer efficiency of about 50%. It also leads to good reproducibility of a capillary discharge which is necessary for lasing a SXRL stably. For the study of the possibility of lasing a SXRL at shorter wavelength in a small laboratory scale, high-density and high-temperature plasma column suitable for the laser can be generated relatively easily with this system.

  13. High-efficiency photovoltaic cells

    Science.gov (United States)

    Yang, H.T.; Zehr, S.W.

    1982-06-21

    High efficiency solar converters comprised of a two cell, non-lattice matched, monolithic stacked semiconductor configuration using optimum pairs of cells having bandgaps in the range 1.6 to 1.7 eV and 0.95 to 1.1 eV, and a method of fabrication thereof, are disclosed. The high band gap subcells are fabricated using metal organic chemical vapor deposition (MOCVD), liquid phase epitaxy (LPE) or molecular beam epitaxy (MBE) to produce the required AlGaAs layers of optimized composition, thickness and doping to produce high performance, heteroface homojunction devices. The low bandgap subcells are similarly fabricated from AlGa(As)Sb compositions by LPE, MBE or MOCVD. These subcells are then coupled to form a monolithic structure by an appropriate bonding technique which also forms the required transparent intercell ohmic contact (IOC) between the two subcells. Improved ohmic contacts to the high bandgap semiconductor structure can be formed by vacuum evaporating to suitable metal or semiconductor materials which react during laser annealing to form a low bandgap semiconductor which provides a low contact resistance structure.

  14. High Efficiency Ka-Band Spatial Combiner

    Directory of Open Access Journals (Sweden)

    D. Passi

    2014-12-01

    Full Text Available A Ka-Band, High Efficiency, Small Size Spatial Combiner (SPC is proposed in this paper, which uses an innovatively matched quadruple Fin Lines to microstrip (FLuS transitions. At the date of this paper and at the Author's best knowledge no such FLuS innovative transitions have been reported in literature before. These transitions are inserted into a WR28 waveguide T-junction, in order to allow the integration of 16 Monolithic Microwave Integrated Circuit (MMIC Solid State Power Amplifiers (SSPA's. A computational electromagnetic model using the finite elements method has been implemented. A mean insertion loss of 2 dB is achieved with a return loss better the 10 dB in the 31-37 GHz bandwidth.

  15. High efficiency beam splitting for H- accelerators

    International Nuclear Information System (INIS)

    Kramer, S.L.; Stipp, V.; Krieger, C.; Madsen, J.

    1985-01-01

    Beam splitting for high energy accelerators has typically involved a significant loss of beam and radiation. This paper reports on a new method of splitting beams for H - accelerators. This technique uses a high intensity flash of light to strip a fraction of the H - beam to H 0 which are then easily separated by a small bending magnet. A system using a 900-watt (average electrical power) flashlamp and a highly efficient collector will provide 10 -3 to 10 -2 splitting of a 50 MeV H - beam. Results on the operation and comparisons with stripping cross sections are presented. Also discussed is the possibility for developing this system to yield a higher stripping fraction

  16. Clean fossil-fuelled power generation

    International Nuclear Information System (INIS)

    Oliver, Tony

    2008-01-01

    Using fossil fuels is likely to remain the dominant means of producing electricity in 2030 and even 2050, partly because power stations have long lives. There are two main ways of reducing CO 2 emissions from fossil-fuelled power plants. These are carbon capture and storage (CCS), which can produce near-zero CO 2 emissions, and increases in plant efficiency, which can give rise to significant reductions in CO 2 emissions and to reduced costs. If a typical UK coal-fired plant was replaced by today's best available technology, it would lead to reductions of around 25% in emissions of CO 2 per MW h of electricity produced. Future technologies are targeting even larger reductions in emissions, as well as providing a route, with CCS, to zero emissions. These two routes are linked and they are both essential activities on the pathway to zero emissions. This paper focuses on the second route and also covers an additional third route for reducing emissions, the use of biomass. It discusses the current status of the science and technologies for fossil-fuelled power generation and outlines likely future technologies, development targets and timescales. This is followed by a description of the scientific and technological developments that are needed to meet these challenges. Once built, a power plant can last for over 40 years, so the ability to upgrade and retrofit a plant during its lifetime is important

  17. High efficiency turbine blade coatings

    Energy Technology Data Exchange (ETDEWEB)

    Youchison, Dennis L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Gallis, Michail A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2014-06-01

    The development of advanced thermal barrier coatings (TBCs) of yttria stabilized zirconia (YSZ) that exhibit lower thermal conductivity through better control of electron beam - physical vapor deposition (EB-PVD) processing is of prime interest to both the aerospace and power industries. This report summarizes the work performed under a two-year Lab-Directed Research and Development (LDRD) project (38664) to produce lower thermal conductivity, graded-layer thermal barrier coatings for turbine blades in an effort to increase the efficiency of high temperature gas turbines. This project was sponsored by the Nuclear Fuel Cycle Investment Area. Therefore, particular importance was given to the processing of the large blades required for industrial gas turbines proposed for use in the Brayton cycle of nuclear plants powered by high temperature gas-cooled reactors (HTGRs). During this modest (~1 full-time equivalent (FTE)) project, the processing technology was developed to create graded TBCs by coupling ion beam-assisted deposition (IBAD) with substrate pivoting in the alumina-YSZ system. The Electron Beam - 1200 kW (EB-1200) PVD system was used to deposit a variety of TBC coatings with micron layered microstructures and reduced thermal conductivity below 1.5 W/m.K. The use of IBAD produced fully stoichiometric coatings at a reduced substrate temperature of 600°C and a reduced oxygen background pressure of 0.1 Pa. IBAD was also used to successfully demonstrate the transitioning of amorphous PVD-deposited alumina to the -phase alumina required as an oxygen diffusion barrier and for good adhesion to the substrate Ni2Al3 bondcoat. This process replaces the time consuming thermally grown oxide formation required before the YSZ deposition. In addition to the process technology, Direct Simulation Monte Carlo plume modeling and spectroscopic characterization of the PVD plumes were performed. The project consisted of five tasks. These included the

  18. High efficiency double sided solar cells

    International Nuclear Information System (INIS)

    Seddik, M.M.

    1990-06-01

    Silicon technology state of the art for single crystalline was given to be limited to less than 20% efficiency. A proposed new form of photovoltaic solar cell of high current high efficiency with double sided structures has been given. The new forms could be n ++ pn ++ or p ++ np ++ double side junctions. The idea of double sided devices could be understood as two solar cells connected back-to-back in parallel electrical connection, in which the current is doubled if the cell is illuminated from both sides by a V-shaped reflector. The cell is mounted to the reflector such that each face is inclined at an angle of 45 deg. C to each side of the reflector. The advantages of the new structure are: a) High power devices. b) Easy to fabricate. c) The cells are used vertically instead of horizontal use of regular solar cell which require large area to install. This is very important in power stations and especially for satellite installation. If the proposal is made real and proved to be experimentally feasible, it would be a new era for photovoltaic solar cells since the proposal has already been extended to even higher currents. The suggested structures could be stated as: n ++ pn ++ Vp ++ np ++ ;n ++ pn ++ Vn ++ pn ++ ORp ++ np ++ Vp ++ np ++ . These types of structures are formed in wedged shape to employ indirect illumination by either parabolic; conic or V-shaped reflectors. The advantages of these new forms are low cost; high power; less in size and space; self concentrating; ... etc. These proposals if it happens to find their ways to be achieved experimentally, I think they will offer a short path to commercial market and would have an incredible impact on solar cell technology and applications. (author). 12 refs, 5 figs

  19. 1998 report on development of high-efficiency waste power generation technology. 2. Development of waste gasification and ash melting power generation technology; 1998 nendo kokoritsu haikibutsu hatsuden gijutsu kaihatsu seika hokokusho. Haikibutsu gas ka yoyu hatsuden gijutsu kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-01

    In regard to waste gasification and ash melting power generation, a basic test and examination were conducted in fiscal 1998, with a full-scale development test made ready to start. In the development of technology for raising steam temperature, evaluation of high temperature corrosivity of SH materials and development of high-temperature dust removal system were carried out for example, as were development of dechlorination technology for thermal decomposition process and development of ceramic high-temperature air heater. In the development of technology to prevent exhaust gas reheating, preliminary examination was made on denitrification technologies using a catalyst with superior low-temperature activity. In the development of technology to reduce self-heat melting critical calorific value, investigation and basic test were carried out concerning a stable waste feed system, with a pilot test device experimentally manufactured and tested based on the findings. In the development of technology for reducing external fuel input, examination and analysis were performed on pretreatment techniques for waste plastics, with basic data obtained for a waste blowing system project. In addition, the thermal decomposition and combustion characteristics of waste plastics were clarified by the basic test. (NEDO)

  20. High-Efficiency Klystron Design for the CLIC Project

    CERN Document Server

    Mollard, Antoine; Peauger, Franck; Plouin, Juliette; Beunas, Armel; Marchesin, Rodolphe

    2017-01-01

    The CLIC project requests new type of RF sources for the high power conditioning of the accelerating cavities. We are working on the development of a new kind of high-efficiency klystron to fulfill this need. This work is performed under the EuCARD-2 European program and involves theoretical and experimental study of a brand new klystron concept.

  1. Multi-petascale highly efficient parallel supercomputer

    Science.gov (United States)

    Asaad, Sameh; Bellofatto, Ralph E.; Blocksome, Michael A.; Blumrich, Matthias A.; Boyle, Peter; Brunheroto, Jose R.; Chen, Dong; Cher, Chen -Yong; Chiu, George L.; Christ, Norman; Coteus, Paul W.; Davis, Kristan D.; Dozsa, Gabor J.; Eichenberger, Alexandre E.; Eisley, Noel A.; Ellavsky, Matthew R.; Evans, Kahn C.; Fleischer, Bruce M.; Fox, Thomas W.; Gara, Alan; Giampapa, Mark E.; Gooding, Thomas M.; Gschwind, Michael K.; Gunnels, John A.; Hall, Shawn A.; Haring, Rudolf A.; Heidelberger, Philip; Inglett, Todd A.; Knudson, Brant L.; Kopcsay, Gerard V.; Kumar, Sameer; Mamidala, Amith R.; Marcella, James A.; Megerian, Mark G.; Miller, Douglas R.; Miller, Samuel J.; Muff, Adam J.; Mundy, Michael B.; O'Brien, John K.; O'Brien, Kathryn M.; Ohmacht, Martin; Parker, Jeffrey J.; Poole, Ruth J.; Ratterman, Joseph D.; Salapura, Valentina; Satterfield, David L.; Senger, Robert M.; Smith, Brian; Steinmacher-Burow, Burkhard; Stockdell, William M.; Stunkel, Craig B.; Sugavanam, Krishnan; Sugawara, Yutaka; Takken, Todd E.; Trager, Barry M.; Van Oosten, James L.; Wait, Charles D.; Walkup, Robert E.; Watson, Alfred T.; Wisniewski, Robert W.; Wu, Peng

    2015-07-14

    A Multi-Petascale Highly Efficient Parallel Supercomputer of 100 petaOPS-scale computing, at decreased cost, power and footprint, and that allows for a maximum packaging density of processing nodes from an interconnect point of view. The Supercomputer exploits technological advances in VLSI that enables a computing model where many processors can be integrated into a single Application Specific Integrated Circuit (ASIC). Each ASIC computing node comprises a system-on-chip ASIC utilizing four or more processors integrated into one die, with each having full access to all system resources and enabling adaptive partitioning of the processors to functions such as compute or messaging I/O on an application by application basis, and preferably, enable adaptive partitioning of functions in accordance with various algorithmic phases within an application, or if I/O or other processors are underutilized, then can participate in computation or communication nodes are interconnected by a five dimensional torus network with DMA that optimally maximize the throughput of packet communications between nodes and minimize latency.

  2. Charge transport in highly efficient iridium cored electrophosphorescent dendrimers

    Science.gov (United States)

    Markham, Jonathan P. J.; Samuel, Ifor D. W.; Lo, Shih-Chun; Burn, Paul L.; Weiter, Martin; Bässler, Heinz

    2004-01-01

    Electrophosphorescent dendrimers are promising materials for highly efficient light-emitting diodes. They consist of a phosphorescent core onto which dendritic groups are attached. Here, we present an investigation into the optical and electronic properties of highly efficient phosphorescent dendrimers. The effect of dendrimer structure on charge transport and optical properties is studied using temperature-dependent charge-generation-layer time-of-flight measurements and current voltage (I-V) analysis. A model is used to explain trends seen in the I-V characteristics. We demonstrate that fine tuning the mobility by chemical structure is possible in these dendrimers and show that this can lead to highly efficient bilayer dendrimer light-emitting diodes with neat emissive layers. Power efficiencies of 20 lm/W were measured for devices containing a second-generation (G2) Ir(ppy)3 dendrimer with a 1,3,5-tris(2-N-phenylbenzimidazolyl)benzene electron transport layer.

  3. High Efficiency Power Converter for Low Voltage High Power Applications

    OpenAIRE

    Nymand, Morten; Andersen, Michael A. E.

    2010-01-01

    Emnet for denne Ph.d. afhandling er design af effektelektroniske dc-dc konvertere med meget høj virkningsgrad til anvendelser med høj udgangseffekt, lav indgangsspænding samt høj udgangsspænding. Disse konvertere anvendes i stigende grad indenfor vedvarende energisystemer baseret på brændselsceller, batterier eller solceller. Anvendelserne omfatter nødstrømsanlæg (UPS), decentrale mikro-kraftvarmeanlæg, transportsystemer så som elektriske hybridbiler, gaffeltrucks samt særlige anvendelser ind...

  4. A combination of Stirling engine and high-efficiency boiler. Microsize cogeneration unit for heat and power supply; Stirlingmotor und Brennwertkessel vereint. Mikro-Waermekraftkopplung liefert Strom und Waerme

    Energy Technology Data Exchange (ETDEWEB)

    Donnerbauer, R.

    2001-03-01

    Apart from the heat pump and fuel cell, there is another new development: At the ISH in March, the Dutch producer EnAtEc intends to present a microsize cogeneration unit consisting of a gas-fuelled high-efficiency boiler and a free-piston Stirling motor. [German] Sind die Wirkungsgrade in der Heiztechnik ausgenutzt? Auf die Frage 'Was kommt nach der Brennwerttechnik?' gibt es jetzt neben Waermepumpe und Brennstoffzelle eine neue Antwort. Zur kommenden ISH Ende Maerz hat die niederlaendische Firma EnAtEc die Vorstellung einer 'Mikro-Waermekraftkopplung' ({mu}WK) angekuendigt. Das Geraet kombiniert einen Gas-Brennwertkessel mit einer Freikolben-Stirlingmaschine. (orig.)

  5. All passive architecture for high efficiency cascaded Raman conversion

    Science.gov (United States)

    Balaswamy, V.; Arun, S.; Chayran, G.; Supradeepa, V. R.

    2018-02-01

    Cascaded Raman fiber lasers have offered a convenient method to obtain scalable, high-power sources at various wavelength regions inaccessible with rare-earth doped fiber lasers. A limitation previously was the reduced efficiency of these lasers. Recently, new architectures have been proposed to enhance efficiency, but this came at the cost of enhanced complexity, requiring an additional low-power, cascaded Raman laser. In this work, we overcome this with a new, all-passive architecture for high-efficiency cascaded Raman conversion. We demonstrate our architecture with a fifth-order cascaded Raman converter from 1117nm to 1480nm with output power of ~64W and efficiency of 60%.

  6. High Efficient Bidirectional Battery Converter for residential PV Systems

    DEFF Research Database (Denmark)

    Pham, Cam; Kerekes, Tamas; Teodorescu, Remus

    2012-01-01

    Photovoltaic (PV) installation is suited for the residential environment and the generation pattern follows the distribution of residential power consumption in daylight hours. In the cases of unbalance between generation and demand, the Smart PV with its battery storage can absorb or inject...... the power to balance it. High efficient bidirectional converter for the battery storage is required due high system cost and because the power is processed twice. A 1.5kW prototype is designed and built with CoolMOS and SiC diodes, >;95% efficiency has been obtained with 200 kHz hard switching....

  7. Irradiation effects on high efficiency Si solar cells

    International Nuclear Information System (INIS)

    Nguyen Duy, T.; Amingual, D.; Colardelle, P.; Bernard, J.

    1974-01-01

    By optimizing the diffusion parameters, high efficiency cells are obtained with 2ohmsxcm (13.5% AMO) and 10ohmsxcm (12.5% AMO) silicon material. These new cells have been submitted to radiation tests under 1MeV, 2MeV electrons and 2.5MeV protons. Their behavior under irradiation is found to be dependent only on the bulk material. By using the same resistivity silicon, the rate of degradation is exactly the same than those of conventional cells. The power increase, due to a better superficial response of the cell, is maintained after irradiation. These results show that new high efficiency cells offer an E.O.L. power higher than conventional cells [fr

  8. Measure Guideline. High Efficiency Natural Gas Furnaces

    Energy Technology Data Exchange (ETDEWEB)

    Brand, L. [Partnership for Advanced Residential Retrofit (PARR), Des Plaines, IL (United States); Rose, W. [Partnership for Advanced Residential Retrofit (PARR), Des Plaines, IL (United States)

    2012-10-01

    This measure guideline covers installation of high-efficiency gas furnaces, including: when to install a high-efficiency gas furnace as a retrofit measure; how to identify and address risks; and the steps to be used in the selection and installation process. The guideline is written for Building America practitioners and HVAC contractors and installers. It includes a compilation of information provided by manufacturers, researchers, and the Department of Energy as well as recent research results from the Partnership for Advanced Residential Retrofit (PARR) Building America team.

  9. Measure Guideline: High Efficiency Natural Gas Furnaces

    Energy Technology Data Exchange (ETDEWEB)

    Brand, L.; Rose, W.

    2012-10-01

    This Measure Guideline covers installation of high-efficiency gas furnaces. Topics covered include when to install a high-efficiency gas furnace as a retrofit measure, how to identify and address risks, and the steps to be used in the selection and installation process. The guideline is written for Building America practitioners and HVAC contractors and installers. It includes a compilation of information provided by manufacturers, researchers, and the Department of Energy as well as recent research results from the Partnership for Advanced Residential Retrofit (PARR) Building America team.

  10. Lightweight High Efficiency Electric Motors for Space Applications

    Science.gov (United States)

    Robertson, Glen A.; Tyler, Tony R.; Piper, P. J.

    2011-01-01

    Lightweight high efficiency electric motors are needed across a wide range of space applications from - thrust vector actuator control for launch and flight applications to - general vehicle, base camp habitat and experiment control for various mechanisms to - robotics for various stationary and mobile space exploration missions. QM Power?s Parallel Path Magnetic Technology Motors have slowly proven themselves to be a leading motor technology in this area; winning a NASA Phase II for "Lightweight High Efficiency Electric Motors and Actuators for Low Temperature Mobility and Robotics Applications" a US Army Phase II SBIR for "Improved Robot Actuator Motors for Medical Applications", an NSF Phase II SBIR for "Novel Low-Cost Electric Motors for Variable Speed Applications" and a DOE SBIR Phase I for "High Efficiency Commercial Refrigeration Motors" Parallel Path Magnetic Technology obtains the benefits of using permanent magnets while minimizing the historical trade-offs/limitations found in conventional permanent magnet designs. The resulting devices are smaller, lower weight, lower cost and have higher efficiency than competitive permanent magnet and non-permanent magnet designs. QM Power?s motors have been extensively tested and successfully validated by multiple commercial and aerospace customers and partners as Boeing Research and Technology. Prototypes have been made between 0.1 and 10 HP. They are also in the process of scaling motors to over 100kW with their development partners. In this paper, Parallel Path Magnetic Technology Motors will be discussed; specifically addressing their higher efficiency, higher power density, lighter weight, smaller physical size, higher low end torque, wider power zone, cooler temperatures, and greater reliability with lower cost and significant environment benefit for the same peak output power compared to typically motors. A further discussion on the inherent redundancy of these motors for space applications will be provided.

  11. Saving energy via high-efficiency fans.

    Science.gov (United States)

    Heine, Thomas

    2016-08-01

    Thomas Heine, sales and market manager for EC Upgrades, the retrofit arm of global provider of air movement solutions, ebm-papst A&NZ, discusses the retrofitting of high-efficiency fans to existing HVAC equipment to 'drastically reduce energy consumption'.

  12. High-efficiency silicon solar cells for low-illumination applications

    OpenAIRE

    Glunz, S.W.; Dicker, J.; Esterle, M.; Hermle, M.; Isenberg, J.; Kamerewerd, F.; Knobloch, J.; Kray, D.; Leimenstoll, A.; Lutz, F.; Oßwald, D.; Preu, R.; Rein, S.; Schäffer, E.; Schetter, C.

    2002-01-01

    At Fraunhofer ISE the fabrication of high-efficiency solar cells was extended from a laboratory scale to a small pilot-line production. Primarily, the fabricated cells are used in small high-efficiency modules integrated in prototypes of solar-powered portable electronic devices such as cellular phones, handheld computers etc. Compared to other applications of high-efficiency cells such as solar cars and planes, the illumination densities found in these mainly indoor applications are signific...

  13. 依靠技术创新,安全高效发展核电,治理雾霾源头%Rely on Technological Innovation to Develop High Efficient Nuclear Power Generation Safely to Handel Haze Sources

    Institute of Scientific and Technical Information of China (English)

    周梦君

    2015-01-01

    It introduces haze's harmful effects and causes. It describes working principle of nuclear power, which determines ‘zero haze’ characteristics. In comparison with nuclear power generation and coal-fired power generation based on greenhouse gas emission and harm effect on environment, the paper points out that developing nuclear power has to adheres to‘safty and high efficiency’, which means we should accelerate innovative nuclear power technology in order to ensure safe and high-effective nuclear power development.%介绍了雾霾的危害和雾霾的成因。阐述了核发电的原理决定了核电的“零雾霾”特性;并在温室气体排放及对环境的影响两方面对核电与煤电做了比较,最后指出,发展核电必须始终坚持“安全、高效”;要确保核电安全高效发展,就必须依靠核电技术创新。

  14. Development of Technologies on Innovative-Simplified Nuclear Power Plant Using High-Efficiency Steam Injectors (12) Evaluations of Spatial Distributions of Flow and Heat Transfer in Steam Injector

    International Nuclear Information System (INIS)

    Yutaka Abe; Yujiro Kawamoto; Chikako Iwaki; Tadashi Narabayashi; Michitsugu Mori; Shuichi Ohmori

    2006-01-01

    Next-generation nuclear reactor systems have been under development aiming at simplified system and improvement of safety and credibility. One of the innovative technologies is the supersonic steam injector, which has been investigated as one of the most important component of the next-generation nuclear reactor. The steam injector has functions of a passive pump without large motor or turbo-machinery and a high efficiency heat exchanger. The performances of the supersonic steam injector as a pump and a heat exchanger are dependent on direct contact condensation phenomena between a supersonic steam and a sub-cooled water jet. In previous studies of the steam injector, there are studies about the operating characteristics of steam injector and about the direct contact condensation between static water pool and steam in atmosphere. However, there is a little study about the turbulent heat transfer and flow behavior under the great shear stress. In order to examine the heat transfer and flow behavior in supersonic steam injector, it is necessary to measure the spatial temperature distribution and velocity in detail. The present study, visible transparent supersonic steam injector is used to obtain the axial pressure distributions in the supersonic steam injector, as well as high speed visual observation of water jet and steam interface. The experiments are conducted with and without non-condensable gas. The experimental results of the interfacial flow behavior between steam and water jet are obtained. It is experimentally clarified that an entrainment exists on the water jet surface. It is also clarified that discharge pressure is depended on the steam supply pressure, the inlet water flow rate, the throat diameter and non-condensable flow rate. Finally a heat flux is estimated about 19 MW/m 2 without non-condensable gas condition in steam. (authors)

  15. Report on technological achievements in fiscal 1999. Institutions for research and development of new environmental industry creating type technologies (Development of harmful substance reducing device for incineration furnaces using high-efficiency power pulse technology); 1999 nendo shinki kankyo sangyo soshutsugata kenkyu kaihatsu seido seika hokokusho. Kokoritsu pulse power gijutsu wo mochiita shokyakuroyo yugai busshitsu sakugen sochi no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-03-01

    Development has been proceeded on a harmful substance (SOx, NOx, Dioxine, etc.) reducing device for incineration furnaces that can be installed retroactively to existing incineration facilities, using high-efficiency power pulse technology of energy saving type, and discharge in honeycomb ceramics. The developmental activities were advanced by dividing them into researches on (1) research of gas decomposing devices, (2) research of pulse plasma electric power source, and (3) research of SI thyristor for pulse. In the research (1), a pulse plasma experiment and a gas decomposing experiment were performed. In the former experiment, discussions were given on effects of discharge electrode structure on discharge in the honeycomb ceramics, wherein it was made clear that employing the mesh-comb type electrode structure can realize discharge along the ceramics surface. In the latter experiment, it was revealed that the simulated gas (dibenzofuran) can be decomposed to 90% by using a coaxial cylindrical reaction device. In the research (2), studies were performed on increasing voltage and current in the device, as well as on semiconductor driving circuits. In the research (3), studies were made on the high-quality gate zone forming method and the quality conduction zone forming method. (NEDO)

  16. High efficiency lithium-thionyl chloride cell

    Science.gov (United States)

    Doddapaneni, N.

    1982-08-01

    The polarization characteristics and the specific cathode capacity of Teflon bonded carbon electrodes in the Li/SOCl2 system have been evaluated. Doping of electrocatalysts such as cobalt and iron phthalocyanine complexes improved both cell voltage and cell rate capability. High efficiency Li/SOCl2 cells were thus achieved with catalyzed cathodes. The electrochemical reduction of SOCl2 seems to undergo modification at catalyzed cathode. For example, the reduction of SOCl2 at FePc catalyzed cathode involves 2-1/2 e-/mole of SOCl2. Furthermore, the reduction mechanism is simplified and unwanted chemical species are eliminated by the catalyst. Thus a potentially safer high efficiency Li/SOCl2 can be anticipated.

  17. High Efficiency Centrifugal Compressor for Rotorcraft Applications

    Science.gov (United States)

    Medic, Gorazd; Sharma, Om P.; Jongwook, Joo; Hardin, Larry W.; McCormick, Duane C.; Cousins, William T.; Lurie, Elizabeth A.; Shabbir, Aamir; Holley, Brian M.; Van Slooten, Paul R.

    2017-01-01

    A centrifugal compressor research effort conducted by United Technologies Research Center under NASA Research Announcement NNC08CB03C is documented. The objectives were to identify key technical barriers to advancing the aerodynamic performance of high-efficiency, high work factor, compact centrifugal compressor aft-stages for turboshaft engines; to acquire measurements needed to overcome the technical barriers and inform future designs; to design, fabricate, and test a new research compressor in which to acquire the requisite flow field data. A new High-Efficiency Centrifugal Compressor stage -- splittered impeller, splittered diffuser, 90 degree bend, and exit guide vanes -- with aerodynamically aggressive performance and configuration (compactness) goals were designed, fabricated, and subquently tested at the NASA Glenn Research Center.

  18. Standardization on the specification, test and evaluation of high efficiency motors and inverters

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kil Yong [Korea Electric Power Corp. (KEPCO), Taejon (Korea, Republic of). Research Center; Hyun, Chang Soon [Korea Academy of Industrial Technology, Incheon (Korea, Republic of)

    1995-12-31

    Most of the power systems energy is consumed by electrical motors. This report proposes a method for the standardization on the specification, test and evaluation of the high efficiency motors and related inverters. The results of this report can be referred to the rebate program for promoting the use of high efficiency motors and inverters (author). 26 refs., 102 figs.

  19. Critical study of high efficiency deep grinding

    OpenAIRE

    Johnstone, lain

    2002-01-01

    The recent years, the aerospace industry in particular has embraced and actively pursued the development of stronger high performance materials, namely nickel based superalloys and hardwearing steels. This has resulted in a need for a more efficient method of machining, and this need was answered with the advent of High Efficiency Deep Grinding (HEDG). This relatively new process using Cubic Boron Nitride (CBN) electroplated grinding wheels has been investigated through experim...

  20. Report on development of high-efficiency wastes power generation technology in fiscal 1998. 1. Development of component technology, and demonstration test of a pilot plant; 1998 nendo kokoritsu haikibutsu hatsuden gijutsu kaihatsu seika hokokusho. Yoso gijutsu kaihatsu (pilot plant jissho shiken) (dai 1 bunsatsu)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-01

    A technology is developed to perform high-efficiency power generation by generating high-temperature and high-pressure steam stably by burning general wastes and combustible industrial wastes as fuel. This paper describes summary of the achievements in fiscal 1998. Corrosion tests were performed on over-heater materials under steam condition of 500 degrees C and 100 kg/cm{sup 2} by using a hot model. It was verified by the tests that the corrosion environment around an external heat exchanger is milder than that with an external stack. A circulation fluid bed was simulated from operation data, and a prospect was obtained on steam conditions required for the high-efficiency power generation. In order to elucidate the corrosion mechanism, discussions were given on deposited ash properties, corrosion characteristics and stress. Elucidation was made on a discharge chamber structure most suitable for removing dioxins and NOx by using a waste gas treatment process that uses plasma generated by discharge. A concept design was made. The economic effect of the system is equivalent to that of the activated carbon blow-in process, whereas a waste gas treatment system was nearly completed. As a result of the pilot plant test, the power generation efficiency is estimated to be 30% in a scale of 1200 tons per 24 hours. A demonstration test revealed that dioxin emission was far below the regulation value. An optimal system was also discussed. (NEDO)

  1. Environment-friendly type energy and coordinated community development project. Feasibility study for industrialization of high efficiency waste-fired power generation system (industrial refuse derived fuel and gas turbine combined type); Kankyo chowagata energy community keisei sokushin. Kokoritsu haikibutsu hatsuden (sangyo RDF GT fukugogata) jigyoka FS chosa

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-03-01

    High efficiency power generation, which is useful for promoting the environment-friendly type energy and coordinated community, is investigated by combining a steam turbine power generation system using the PS-RDF (paper sludge-refuse derived fuel) and a gas turbine (GT) combined cycle. Industrialization plan for processing PS in low cost has been made to ensure the profitability by participating the wholesale power supply under the law of electric power industry. This combined system is similar to the so-called super power generation using municipal garbage, but the lower temperature of steam from GT waste heat boilers (WHB) is super-heated by the flue gas from RDF boiler, which is called advanced power generation system (A.S.S.). The total power generation capacity is 149,000 kW, which consists of three 35,000 kW units of GT and one 44,000 kW unit of steam turbine. When comparing the combined system (A.S.S.) and usual one with the independent installation of the RDF steam power generation system and a GT combined cycle, the A.S.S. provides the repowering efficiency of 7,600 kW output with exactly the same quantity of fuel input as usual one. 71 figs., 31 tabs.

  2. High currents, low voltages. Low-cost, high efficiency power supply meets the requirements of Intel Mobile Voltage Positioning; Von dicken Stroemen und kleinen Spannungen. Preiswerte Stromversorgung mit hohem Wirkungsgrad erfuellt die Anforderungen des Intel Mobile Voltage Positioning

    Energy Technology Data Exchange (ETDEWEB)

    Chen, V.W.; Guan, P.; Chen, D. [Linear Technology, CA (United States)

    2001-12-27

    The increasing demands on notebook computers have clock rates and currents and reduced voltages as CPUs are produced in increasingly smaller structural sizes. This makes high demands on power supply. [German] Die steigende Nachfrage nach Rechenleistung in Notebook-Computern hat zu einem betraechtlichen Anstieg der Taktfrequenzen und der Stromaufnahme der CPUs gefuehrt. Gleichzeitig sind die Versorgungsspannungen erheblich gesunken, da die CPUs in Prozessen mit immer kleineren Strukturgroessen hergestellt werden. Als die CPU-Taktfrequenzen 1 GHz ueberstiegen, hat die Stromaufnahme der CPU erstmals 20 A ueberschritten, und die minimale Versorgungsspannung ist auf unter 1 V gefallen. Dies stellt gewaltige Anforderungen an die Stromversorgungen. (orig.)

  3. FY 2000 report on the survey of the project to promote and support the formation of the environmentally friendly energy community. Feasibility study on the waste utilization high efficiency power generation project; Kankyo chowagata energy community keisei sokushin jigyo chosa hokokusho. Haikibutsu riyo kokoritsu hatsuden jigyo ni kakawaru FS chosa

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-03-01

    An investigational study was conducted on energy recovery (power generation) in disposal of industrial waste. The capacity of power generation facilities in incineration processing of industrial waste reached approximately 200,000kW (50 facilities) in the total nationwide. The incineration-processed waste is mainly chips of wood, waste tire and bagasse. Almost all the electric power is for non-utility use, and there are no examples of selling it outside. In the metropolitan area, there is only one example of the industrial waste incineration power generation in Tochigi prefecture. This is because there are extremely very few enterprises which are sources producing the waste as target. However, if the industrial waste market is targeted, there is a future. The industrial waste has a lot of disadvantages as power generation use fuel because of its diversification, but the use of it as fuel is technically easier than the use of the general waste as RDF. Accordingly, it can be used for power generation with no need of special technology or facilities. When picking up facilities with a potentiality of high efficiency power generation from the existing incinerators in operation of persons in charge of industrial waste processing, approximately 125,000 kW can be obtained only from remodeling of the existing facilities. (NEDO)

  4. Environment-friendly type energy and coordinated community development project. Feasibility study for industrialization of high efficiency waste-fired power generation system using CSD and other wastes; Kankyo chowagata energy community keisei sokushin. Kokoritsu haikibutsu hatsuden (CSD nado haikibutsu riyo) jigyoka FS chosa

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-03-01

    This report presents the feasibility of enterprise on power generation by thermal recycle and selling power together with volume reduction, de-harming (de-toxification) and stabilization of the shredder dust. Contents of the study include the investigation of generation amount of car shredder dust (CSD) and its properties, trial design of high efficiency power generation facilities, selection of boiler tube materials, incineration test with a melting kiln test plant, disposal and effective use of melted slag and fly ash, and environmental impact assessment. The capacity of waste disposal in the trial design contains 1,140 ton/day of shredder dust, 60 ton/day of waste plastics, sludge and waste paper, and 130 ton/day of waste oil. Melting kiln with secondary combustion chamber was adopted as the incineration type. The high temperature and high pressure waste heat boiler with an extraction condensing turbine was adopted as the waste heat recovery and power generation type. Stable combustion was confirmed from the results using a test plant. According to the consideration of cost and unit cost results for wholesale power supply, if it is postulated that income for waste disposal is 12,000 yen/ton, power generation costs in excess power selling and wholesales are 6.4 yen/kWh and 9.1 yen/kWh, respectively. 67 figs., 48 tabs.

  5. Report on a project to support promotion of forming an environmentally friendly energy community. Survey on an environmentally friendly community business by means of high-efficiency wastes power generation system in the Toyota-Kamo wide area; Kankyo chowagata energy community keisei sokushin hojo jigyo chosa hokokusho. Toyota Kamo koikiken kokoritsu haikibutsu hatsuden kankyo chowagata energy community jigyo chosa

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-01

    Taking the Toyota-Kamo wide area as the object, wastes power generation is positioned over the society system as worked on by administrations and operators integrally to incinerate mixedly those incineratable materials such as plastics among general and industrial combustible wastes for high-efficiency generation of power, which is supplied to electric utility operators as surplus power. Discussions were given on the business feasibility and the effectiveness as a society system. In this area, the mixed model B plan (dealing with general wastes plus industrial wastes) was evaluated as an effective plan as the society system. This is because the plan has effect to incinerate, melt and generate power from industrial wastes which have been used for land-fill, effect of improving the power generation efficiency, and effectiveness of mixed treatment with general wastes. The plan A in which general wastes are made into RDF, then incinerated mixedly with industrial wastes for power generation was evaluated to have high reliability potential of power supply and to be an effective plan as a society system, if effect can be expected to reduce transportation energy as a result of making the system large enough and turning wastes into RDF. (NEDO)

  6. High Efficiency, Illumination Quality OLEDs for Lighting

    Energy Technology Data Exchange (ETDEWEB)

    Joseph Shiang; James Cella; Kelly Chichak; Anil Duggal; Kevin Janora; Chris Heller; Gautam Parthasarathy; Jeffery Youmans; Joseph Shiang

    2008-03-31

    . In 2003, a large area, OLED based illumination source was demonstrated that could provide light with a quality, quantity, and efficiency on par with what can be achieved with traditional light sources. The demonstration source was made by tiling together 16 separate 6-inch x 6-inch blue-emitting OLEDs. The efficiency, total lumen output, and lifetime of the OLED based illumination source were the same as what would be achieved with an 80 watt incandescent bulb. The devices had an average efficacy of 15 LPW and used solution-processed OLEDs. The individual 6-inch x 6-inch devices incorporated three technology strategies developed specifically for OLED lighting -- downconversion for white light generation, scattering for outcoupling efficiency enhancement, and a scalable monolithic series architecture to enable large area devices. The downconversion approach consists of optically coupling a blue-emitting OLED to a set of luminescent layers. The layers are chosen to absorb the blue OLED emission and then luminescence with high efficiency at longer wavelengths. The composition and number of layers are chosen so that the unabsorbed blue emission and the longer wavelength re-emission combine to make white light. A downconversion approach has the advantage of allowing a wide variety of colors to be made from a limited set of blue emitters. In addition, one does not have to carefully tune the emission wavelength of the individual electro-luminescent species within the OLED device in order to achieve white light. The downconversion architecture used to develop the 15LPW large area light source consisted of a polymer-based blue-emitting OLED and three downconversion layers. Two of the layers utilized perylene based dyes from BASF AG of Germany with high quantum efficiency (>98%) and one of the layers consisted of inorganic phosphor particles (Y(Gd)AG:Ce) with a quantum efficiency of {approx}85%. By independently varying the optical density of the downconversion layers, the

  7. High efficiency and broadband acoustic diodes

    Science.gov (United States)

    Fu, Congyi; Wang, Bohan; Zhao, Tianfei; Chen, C. Q.

    2018-01-01

    Energy transmission efficiency and working bandwidth are the two major factors limiting the application of current acoustic diodes (ADs). This letter presents a design of high efficiency and broadband acoustic diodes composed of a nonlinear frequency converter and a linear wave filter. The converter consists of two masses connected by a bilinear spring with asymmetric tension and compression stiffness. The wave filter is a linear mass-spring lattice (sonic crystal). Both numerical simulation and experiment show that the energy transmission efficiency of the acoustic diode can be improved by as much as two orders of magnitude, reaching about 61%. Moreover, the primary working band width of the AD is about two times of the cut-off frequency of the sonic crystal filter. The cut-off frequency dependent working band of the AD implies that the developed AD can be scaled up or down from macro-scale to micro- and nano-scale.

  8. Experiments on high efficiency aerosol filtration

    International Nuclear Information System (INIS)

    Mazzini, M.; Cuccuru, A.; Kunz, P.

    1977-01-01

    Research on high efficiency aerosol filtration by the Nuclear Engineering Institute of Pisa University and by CAMEN in collaboration with CNEN is outlined. HEPA filter efficiency was studied as a function of the type and size of the test aerosol, and as a function of flowrate (+-50% of the nominal value), air temperature (up to 70 0 C), relative humidity (up to 100%), and durability in a corrosive atmosphere (up to 140 hours in NaCl mist). In the selected experimental conditions these influences were appreciable but are not sufficient to be significant in industrial HEPA filter applications. Planned future research is outlined: measurement of the efficiency of two HEPA filters in series using a fixed particle size; dependence of the efficiency on air, temperatures up to 300-500 0 C; performance when subject to smoke from burning organic materials (natural rubber, neoprene, miscellaneous plastics). Such studies are relevant to possible accidental fires in a plutonium laboratory

  9. High efficiency motors; Motores de alta eficiencia

    Energy Technology Data Exchange (ETDEWEB)

    Uranga Favela, Ivan Jaime [Energia Controlada de Mexico, S. A. de C. V., Mexico, D. F. (Mexico)

    1993-12-31

    This paper is a technical-financial study of the high efficiency and super-premium motors. As it is widely known, more than 60% of the electrical energy generated in the country is used for the operation of motors, in industry as well as in commerce. Therefore the importance that the motors have in the efficient energy use. [Espanol] El presente trabajo es un estudio tecnico-financiero de los motores de alta eficiencia y los motores super premium. Como es ampliamente conocido, mas del 60% de la energia electrica generada en el pais, es utilizada para accionar motores, dentro de la industria y el comercio. De alli la importancia que los motores tienen en el uso eficiente de la energia.

  10. High efficiency thin-film solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Schock, Hans-Werner [Helmholtz Zentrum Berlin (Germany). Solar Energy

    2012-11-01

    Production of photovoltaics is growing worldwide on a gigawatt scale. Among the thin film technologies, Cu(In,Ga)S,Se{sub 2} (CIS or CIGS) based solar cells have been the focus of more and more attention. This paper aims to analyze the success of CIGS based solar cells and the potential of this technology for future photovoltaics large-scale production. Specific material properties make CIS unique and allow the preparation of the material with a wide range of processing options. The huge potential lies in the possibility to take advantage of modern thin film processing equipment and combine it with very high efficiencies beyond 20% already achieved on the laboratory scale. A sustainable development of this technology could be realized by modifying the materials and replacing indium by abundant elements. (orig.)

  11. Complexity-aware high efficiency video coding

    CERN Document Server

    Correa, Guilherme; Agostini, Luciano; Cruz, Luis A da Silva

    2016-01-01

    This book discusses computational complexity of High Efficiency Video Coding (HEVC) encoders with coverage extending from the analysis of HEVC compression efficiency and computational complexity to the reduction and scaling of its encoding complexity. After an introduction to the topic and a review of the state-of-the-art research in the field, the authors provide a detailed analysis of the HEVC encoding tools compression efficiency and computational complexity.  Readers will benefit from a set of algorithms for scaling the computational complexity of HEVC encoders, all of which take advantage from the flexibility of the frame partitioning structures allowed by the standard.  The authors also provide a set of early termination methods based on data mining and machine learning techniques, which are able to reduce the computational complexity required to find the best frame partitioning structures. The applicability of the proposed methods is finally exemplified with an encoding time control system that emplo...

  12. High efficiency motors; Motores de alta eficiencia

    Energy Technology Data Exchange (ETDEWEB)

    Uranga Favela, Ivan Jaime [Energia Controlada de Mexico, S. A. de C. V., Mexico, D. F. (Mexico)

    1992-12-31

    This paper is a technical-financial study of the high efficiency and super-premium motors. As it is widely known, more than 60% of the electrical energy generated in the country is used for the operation of motors, in industry as well as in commerce. Therefore the importance that the motors have in the efficient energy use. [Espanol] El presente trabajo es un estudio tecnico-financiero de los motores de alta eficiencia y los motores super premium. Como es ampliamente conocido, mas del 60% de la energia electrica generada en el pais, es utilizada para accionar motores, dentro de la industria y el comercio. De alli la importancia que los motores tienen en el uso eficiente de la energia.

  13. Multi-petascale highly efficient parallel supercomputer

    Science.gov (United States)

    Asaad, Sameh; Bellofatto, Ralph E.; Blocksome, Michael A.; Blumrich, Matthias A.; Boyle, Peter; Brunheroto, Jose R.; Chen, Dong; Cher, Chen-Yong; Chiu, George L.; Christ, Norman; Coteus, Paul W.; Davis, Kristan D.; Dozsa, Gabor J.; Eichenberger, Alexandre E.; Eisley, Noel A.; Ellavsky, Matthew R.; Evans, Kahn C.; Fleischer, Bruce M.; Fox, Thomas W.; Gara, Alan; Giampapa, Mark E.; Gooding, Thomas M.; Gschwind, Michael K.; Gunnels, John A.; Hall, Shawn A.; Haring, Rudolf A.; Heidelberger, Philip; Inglett, Todd A.; Knudson, Brant L.; Kopcsay, Gerard V.; Kumar, Sameer; Mamidala, Amith R.; Marcella, James A.; Megerian, Mark G.; Miller, Douglas R.; Miller, Samuel J.; Muff, Adam J.; Mundy, Michael B.; O'Brien, John K.; O'Brien, Kathryn M.; Ohmacht, Martin; Parker, Jeffrey J.; Poole, Ruth J.; Ratterman, Joseph D.; Salapura, Valentina; Satterfield, David L.; Senger, Robert M.; Steinmacher-Burow, Burkhard; Stockdell, William M.; Stunkel, Craig B.; Sugavanam, Krishnan; Sugawara, Yutaka; Takken, Todd E.; Trager, Barry M.; Van Oosten, James L.; Wait, Charles D.; Walkup, Robert E.; Watson, Alfred T.; Wisniewski, Robert W.; Wu, Peng

    2018-05-15

    A Multi-Petascale Highly Efficient Parallel Supercomputer of 100 petaflop-scale includes node architectures based upon System-On-a-Chip technology, where each processing node comprises a single Application Specific Integrated Circuit (ASIC). The ASIC nodes are interconnected by a five dimensional torus network that optimally maximize the throughput of packet communications between nodes and minimize latency. The network implements collective network and a global asynchronous network that provides global barrier and notification functions. Integrated in the node design include a list-based prefetcher. The memory system implements transaction memory, thread level speculation, and multiversioning cache that improves soft error rate at the same time and supports DMA functionality allowing for parallel processing message-passing.

  14. The CRRES high efficiency solar panel

    International Nuclear Information System (INIS)

    Trumble, T.M.

    1991-01-01

    This paper reports on the High Efficiency Solar Panel (HESP) experiments which is to provide both engineering and scientific information concerning the effects of space radiation on advanced gallium arsenide (GaAs) solar cells. The HESP experiment consists of an ambient panel, and annealing panel and a programmable load. This experiment, in conjunction with the radiation measurement experiments abroad the CREES, provides the first opportunity to simultaneously measure the trapped radiation belts and the results of radiation damage to solar cells. The engineering information will result in a design guide for selecting the optimum solar array characteristics for different orbits and different lifetimes. The scientific information will provide both correlation of laboratory damage effects to space damage effects and a better model for predicting effective solar cell panel lifetimes

  15. High Efficiency, Low Emission Refrigeration System

    Energy Technology Data Exchange (ETDEWEB)

    Fricke, Brian A [ORNL; Sharma, Vishaldeep [ORNL

    2016-08-01

    Supermarket refrigeration systems account for approximately 50% of supermarket energy use, placing this class of equipment among the highest energy consumers in the commercial building domain. In addition, the commonly used refrigeration system in supermarket applications is the multiplex direct expansion (DX) system, which is prone to refrigerant leaks due to its long lengths of refrigerant piping. This leakage reduces the efficiency of the system and increases the impact of the system on the environment. The high Global Warming Potential (GWP) of the hydrofluorocarbon (HFC) refrigerants commonly used in these systems, coupled with the large refrigerant charge and the high refrigerant leakage rates leads to significant direct emissions of greenhouse gases into the atmosphere. Methods for reducing refrigerant leakage and energy consumption are available, but underutilized. Further work needs to be done to reduce costs of advanced system designs to improve market utilization. In addition, refrigeration system retrofits that result in reduced energy consumption are needed since the majority of applications address retrofits rather than new stores. The retrofit market is also of most concern since it involves large-volume refrigerant systems with high leak rates. Finally, alternative refrigerants for new and retrofit applications are needed to reduce emissions and reduce the impact on the environment. The objective of this Collaborative Research and Development Agreement (CRADA) between the Oak Ridge National Laboratory and Hill Phoenix is to develop a supermarket refrigeration system that reduces greenhouse gas emissions and has 25 to 30 percent lower energy consumption than existing systems. The outcomes of this project will include the design of a low emission, high efficiency commercial refrigeration system suitable for use in current U.S. supermarkets. In addition, a prototype low emission, high efficiency supermarket refrigeration system will be produced for

  16. Large-area high-efficiency flexible PHOLED lighting panels

    Science.gov (United States)

    Pang, Huiqing; Mandlik, Prashant; Levermore, Peter A.; Silvernail, Jeff; Ma, Ruiqing; Brown, Julie J.

    2012-09-01

    Organic Light Emitting Diodes (OLEDs) provide various attractive features for next generation illumination systems, including high efficiency, low power, thin and flexible form factor. In this work, we incorporated phosphorescent emitters and demonstrated highly efficient white phosphorescent OLED (PHOLED) devices on flexible plastic substrates. The 0.94 cm2 small-area device has total thickness of approximately 0.25 mm and achieved 63 lm/W at 1,000 cd/m2 with CRI = 85 and CCT = 2920 K. We further designed and fabricated a 15 cm x 15 cm large-area flexible white OLED lighting panels, finished with a hybrid single-layer ultra-low permeability single layer barrier (SLB) encapsulation film. The flexible panel has an active area of 116.4 cm2, and achieved a power efficacy of 47 lm/W at 1,000 cd/m2 with CRI = 83 and CCT = 3470 K. The efficacy of the panel at 3,000 cd/m2 is 43 lm/W. The large-area flexible PHOLED lighting panel is to bring out enormous possibilities to the future general lighting applications.

  17. High efficiency thermal energy storage system for utility applications

    International Nuclear Information System (INIS)

    Vrable, D.L.; Quade, R.N.

    1979-01-01

    A concept of coupling a high efficiency base loaded coal or nuclear power plant with a thermal energy storage scheme for efficient and low-cost intermediate and peaking power is presented. A portion of the power plant's thermal output is used directly to generate superheated steam for continuous operation of a conventional turbine-generator to product base-load power. The remaining thermal output is used on a continuous basis to heat a conventional heat transfer salt (such as the eutectic composition of KaNO 3 /NaNO 3 /NaNO 2 ), which is stored in a high-temperature reservoir [538 0 C (1000 0 F)]. During peak demand periods, the salt is circulated from the high-temperature reservoir to a low-temperature reservoir through steam generators in order to provide peaking power from a conventional steam cycle plant. The period of operation can vary, but may typically be the equivalent of about 4 to 8 full-power hours each day. The system can be tailored to meet the utilities' load demand by varying the base-load level and the period of operation of the peak-load system

  18. Bioblendstocks that Enable High Efficiency Engine Designs

    Energy Technology Data Exchange (ETDEWEB)

    McCormick, Robert L.; Fioroni, Gina M.; Ratcliff, Matthew A.; Zigler, Bradley T.; Farrell, John

    2016-11-03

    The past decade has seen a high level of innovation in production of biofuels from sugar, lipid, and lignocellulose feedstocks. As discussed in several talks at this workshop, ethanol blends in the E25 to E50 range could enable more highly efficient spark-ignited (SI) engines. This is because of their knock resistance properties that include not only high research octane number (RON), but also charge cooling from high heat of vaporization, and high flame speed. Emerging alcohol fuels such as isobutanol or mixed alcohols have desirable properties such as reduced gasoline blend vapor pressure, but also have lower RON than ethanol. These fuels may be able to achieve the same knock resistance benefits, but likely will require higher blend levels or higher RON hydrocarbon blendstocks. A group of very high RON (>150) oxygenates such as dimethyl furan, methyl anisole, and related compounds are also produced from biomass. While providing no increase in charge cooling, their very high octane numbers may provide adequate knock resistance for future highly efficient SI engines. Given this range of options for highly knock resistant fuels there appears to be a critical need for a fuel knock resistance metric that includes effects of octane number, heat of vaporization, and potentially flame speed. Emerging diesel fuels include highly branched long-chain alkanes from hydroprocessing of fats and oils, as well as sugar-derived terpenoids. These have relatively high cetane number (CN), which may have some benefits in designing more efficient CI engines. Fast pyrolysis of biomass can produce diesel boiling range streams that are high in aromatic, oxygen and acid contents. Hydroprocessing can be applied to remove oxygen and consequently reduce acidity, however there are strong economic incentives to leave up to 2 wt% oxygen in the product. This oxygen will primarily be present as low CN alkyl phenols and aryl ethers. While these have high heating value, their presence in diesel fuel

  19. High efficiency novel window air conditioner

    International Nuclear Information System (INIS)

    Bansal, Pradeep

    2015-01-01

    Highlights: • Use of novel refrigerant mixture of R32/R125 (85/15% molar conc.) to reduce global warming and improve energy efficiency. • Use of novel features such as electronically commuted motor (ECM) fan motor, slinger and sub-merged sub-cooler. • Energy savings of up to 0.1 Quads per year in USA and much more in Asia/Middle East where WACs are used in large numbers. • Payback period of only 1.4 years of the novel efficient WAC. - Abstract: This paper presents the results of an experimental and analytical evaluation of measures to raise the efficiency of window air conditioners (WAC). In order to achieve a higher energy efficiency ratio (EER), the original capacity of a baseline R410A unit was reduced by replacing the original compressor with a lower capacity but higher EER compressor, while all heat exchangers and the chassis from the original unit were retained. Subsequent major modifications included – replacing the alternating current fan motor with a brushless high efficiency electronically commutated motor (ECM) motor, replacing the capillary tube with a needle valve to better control the refrigerant flow and refrigerant set points, and replacing R410A with a ‘drop-in’ lower global warming potential (GWP) binary mixture of R32/R125 (85/15% molar concentration). All these modifications resulted in significant enhancement in the EER of the baseline WAC. Further, an economic analysis of the new WAC revealed an encouraging payback period

  20. High efficiency diffusion molecular retention tumor targeting.

    Directory of Open Access Journals (Sweden)

    Yanyan Guo

    Full Text Available Here we introduce diffusion molecular retention (DMR tumor targeting, a technique that employs PEG-fluorochrome shielded probes that, after a peritumoral (PT injection, undergo slow vascular uptake and extensive interstitial diffusion, with tumor retention only through integrin molecular recognition. To demonstrate DMR, RGD (integrin binding and RAD (control probes were synthesized bearing DOTA (for (111 In(3+, a NIR fluorochrome, and 5 kDa PEG that endows probes with a protein-like volume of 25 kDa and decreases non-specific interactions. With a GFP-BT-20 breast carcinoma model, tumor targeting by the DMR or i.v. methods was assessed by surface fluorescence, biodistribution of [(111In] RGD and [(111In] RAD probes, and whole animal SPECT. After a PT injection, both probes rapidly diffused through the normal and tumor interstitium, with retention of the RGD probe due to integrin interactions. With PT injection and the [(111In] RGD probe, SPECT indicated a highly tumor specific uptake at 24 h post injection, with 352%ID/g tumor obtained by DMR (vs 4.14%ID/g by i.v.. The high efficiency molecular targeting of DMR employed low probe doses (e.g. 25 ng as RGD peptide, which minimizes toxicity risks and facilitates clinical translation. DMR applications include the delivery of fluorochromes for intraoperative tumor margin delineation, the delivery of radioisotopes (e.g. toxic, short range alpha emitters for radiotherapy, or the delivery of photosensitizers to tumors accessible to light.

  1. High-efficiency concentrator silicon solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Sinton, R.A.; Cuevas, A.; King, R.R.; Swanson, R.M. (Stanford Univ., CA (USA). Solid-State Electronics Lab.)

    1990-11-01

    This report presents results from extensive process development in high-efficiency Si solar cells. An advanced design for a 1.56-cm{sup 2} cell with front grids achieved 26% efficiency at 90 suns. This is especially significant since this cell does not require a prismatic cover glass. New designs for simplified backside-contact solar cells were advanced from a status of near-nonfunctionality to demonstrated 21--22% for one-sun cells in sizes up to 37.5 cm{sup 2}. An efficiency of 26% was achieved for similar 0.64-cm{sup 2} concentrator cells at 150 suns. More fundamental work on dopant-diffused regions is also presented here. The recombination vs. various process and physical parameters was studied in detail for boron and phosphorous diffusions. Emitter-design studies based solidly upon these new data indicate the performance vs design parameters for a variety of the cases of most interest to solar cell designers. Extractions of p-type bandgap narrowing and the surface recombination for p- and n-type regions from these studies have a generality that extends beyond solar cells into basic device modeling. 68 refs., 50 figs.

  2. High efficiency, variable geometry, centrifugal cryogenic pump

    International Nuclear Information System (INIS)

    Forsha, M.D.; Nichols, K.E.; Beale, C.A.

    1994-01-01

    A centrifugal cryogenic pump has been developed which has a basic design that is rugged and reliable with variable speed and variable geometry features that achieve high pump efficiency over a wide range of head-flow conditions. The pump uses a sealless design and rolling element bearings to achieve high reliability and the ruggedness to withstand liquid-vapor slugging. The pump can meet a wide range of variable head, off-design flow requirements and maintain design point efficiency by adjusting the pump speed. The pump also has features that allow the impeller and diffuser blade heights to be adjusted. The adjustable height blades were intended to enhance the pump efficiency when it is operating at constant head, off-design flow rates. For small pumps, the adjustable height blades are not recommended. For larger pumps, they could provide off-design efficiency improvements. This pump was developed for supercritical helium service, but the design is well suited to any cryogenic application where high efficiency is required over a wide range of head-flow conditions

  3. Blanket options for high-efficiency fusion power

    International Nuclear Information System (INIS)

    Usher, J.L.; Lazareth, O.W.; Fillo, J.A.; Horn, F.L.; Powell, J.R.

    1980-01-01

    The efficiencies of blankets for fusion reactors are usually in the range of 30 to 40%, limited by the operating temperatures (500 0 C) of conventional structural materials such as stainless steels. In this project two-zone blankets are proposed; these blankets consist of a low-temperature shell surrounding a high-temperature interior zone. A survey of nucleonics and thermal hydraulic parameters has led to a reference blanket design consisting of a water-cooled stainless steel shell around a BeO, ZrO 2 interior (cooled by argon) utilizing Li 2 O for tritium breeding. In this design, approximately 60% of the fusion energy is deposited in the high-temperature interior. The maximum argon temperature is 2230 0 C leading to an overall efficiency estimate of 55 to 60% for this reference case

  4. Fusion blankets for high-efficiency power cycles

    International Nuclear Information System (INIS)

    Usher, J.L.; Lazareth, O.W.; Fillo, J.A.; Horn, F.L.; Powell, J.R.

    1980-01-01

    The efficiencies of blankets for fusion reactors are usually in the range of 30 to 40%, limited by the operating temperatures (500 0 C) of conventional structural materials such as stainless steels. In this project two-zone blankets are proposed; these blankets consist of a low-temperature shell surrounding a high-temperature interior zone. A survey of nucleonics and thermal hydraulic parameters has led to a reference blanket design consisting of a water-cooled stainless steel shell around a BeO, ZrO 2 interior (cooled by argon) utilizing Li 2 O for tritium breeding. In this design, approximately 60% of the fusion energy is deposited in the high-temperature interior. The maximum argon temperature is 2230 0 C leading to an overall efficiency estimate of 55 to 60% for this reference case

  5. Fusion blanket for high-efficiency power cycles

    International Nuclear Information System (INIS)

    Usher, J.L.; Powell, J.R.; Fillo, J.A.; Horn, F.L.; Lazareth, O.W.; Taussig, R.

    1980-01-01

    The efficiencies of blankets for fusion reactors are usually in the range of 30 to 40%, limited by the operating temperature (500 0 C) of conventional structural materials such as stainless steels. In this project two-zone blankets are proposed; these blankets consist of a low-temperature shell surrounding a high-temperature interior zone. A survey of nucleonics and thermal hydraulic parameters has led to a reference blanket design consisting of a water-cooled stainless steel shell around a BeO, ZrO 2 interior (cooled by Ar) utilizing Li 2 O for tritium breeding. In this design, approx. 60% of the fusion energy is deposited in the high-temperature interior. The maximum Ar temperature is 2230 0 C leading to an overall efficiency estimate of 55 to 60% for this reference case

  6. Fusion blankets for high-efficiency power cycles

    International Nuclear Information System (INIS)

    Usher, J.L.; Lazareth, O.W.; Fillo, J.A.; Horn, F.L.; Powell, J.R.

    1981-01-01

    The efficiencies of blankets for fusion reactors are usually in the range of 30 to 40%, limited by the operating temperatures (500 deg C) of conventional structural materials such as stainless steels. In this project 'two-zone' blankets are proposed; these blankets consist of a low-temperature shell surrounding a high-temperature interior zone. A survey of nucleonics and thermal hydraulic parameters has led to a reference blanket design consisting of a water-cooled stainless steel shell around a BeO, ZrO 2 interior (cooled by argon) utilizing Li 2 O for tritium breeding. In this design, approximately 60% of the fusion energy is deposited in the high-temperature interior. The maximum argon temperature is 2230 deg C leading to an overall efficiency estimate of 55 to 60% for this reference case. (author)

  7. Wide bandwidth high efficiency power converter for rf amplifiers

    OpenAIRE

    Vasic, Miroslav

    2010-01-01

    Tradicionalmente, en el mundo de la amplificación de potencia de alta frecuencia, se han distinguido dos grandes familias de amplificadores de potencia, atendiendo al efecto de su utilización sobre las señales amplificadas por los mismos: lineales y no lineales. Los amplificadores lineales se han relacionado con las clases de amplificación A, B y AB generalmente poco eficaces en el aprovechamiento de la energía, mientras que los amplificadores no lineales se han asociado a clases de funcionam...

  8. Very-High Efficiency, High Power Laser Diodes, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — AdTech Photonics, in collaboration with the Center for Advanced Studies in Photonics Research (CASPR) at UMBC, is pleased to submit this proposal entitled ?Very-High...

  9. Highly Efficient Fiber Lasers for Wireless Power Transmission, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to develop ytterbium (Yb) fiber lasers with an electrical-to-optical efficiency of nominally 64% by directly coupling 80%-efficient diode lasers with Yb...

  10. A new approach to a high efficiency inductive store

    International Nuclear Information System (INIS)

    Zowarka, R.C. Jr.; Kajs, J.P.; Price, J.H.; Weldon, W.F.

    1991-01-01

    In the Spring of 1989, Parker Kinetic Design, Inc. (PKD) and the Center for Electromechanics at The University of Texas at Austin (CEM-UT) conducted a study to examine the basic technologies to be used in the construction and operation of a feasible and reliable electromagnetic (EM) gun system. This work was performed for Brown and Root Vickers, Ltd. (BRV) in response to a feasibility analysis requirement of the Royal Armament and Development Establishment (RARDE), Ministry of Defence (MD) of the United Kingdom. This paper summarizes that this study focused on the analysis and evaluation of the suitability and applicability of various pulsed power supply options for the performance goals of the RARDE EM gun program. The existing technologies considered included batteries, compulsators, capacitors, and homopolar generators (HPGs). Primary performance specifications for the electrical energy radius system were that it be capable of providing 12 MJ of muzzle energy; velocities between 2.0 and 3.5 km/s; and a repetitive shot rate of up to 10 shots per day, with no more than a 30-min interval between shots. In addition, the recommended system needed to be reliable, easily maintainable, and capable of routinely firing large numbers of shots. Strict adherence to the goal of designing a system based only on demonstrated technology results in power supplies that are prohibitively expensive and large. As a consequence, candidate system designs represent a modest extrapolation from demonstrated technology well within an acceptable design envelope. A new topology has been developed for a highly efficient inductive store suitable for pulsed-power applications. The new design features high L/R ratios without having to cryogenically cool the conductors. This allows for high efficiency charging of the inductor from low impedance dc sources such as batteries of HPGs

  11. High efficiency inductive output tubes with intense annular electron beams

    Science.gov (United States)

    Appanam Karakkad, J.; Matthew, D.; Ray, R.; Beaudoin, B. L.; Narayan, A.; Nusinovich, G. S.; Ting, A.; Antonsen, T. M.

    2017-10-01

    For mobile ionospheric heaters, it is necessary to develop highly efficient RF sources capable of delivering radiation in the frequency range from 3 to 10 MHz with an average power at a megawatt level. A promising source, which is capable of offering these parameters, is a grid-less version of the inductive output tube (IOT), also known as a klystrode. In this paper, studies analyzing the efficiency of grid-less IOTs are described. The basic trade-offs needed to reach high efficiency are investigated. In particular, the trade-off between the peak current and the duration of the current micro-pulse is analyzed. A particle in the cell code is used to self-consistently calculate the distribution in axial and transverse momentum and in total electron energy from the cathode to the collector. The efficiency of IOTs with collectors of various configurations is examined. It is shown that the efficiency of IOTs can be in the 90% range even without using depressed collectors.

  12. Highly Efficient Thermoresponsive Nanocomposite for Controlled Release Applications

    KAUST Repository

    Yassine, Omar

    2016-06-23

    Highly efficient magnetic release from nanocomposite microparticles is shown, which are made of Poly (N-isopropylacrylamide) hydrogel with embedded iron nanowires. A simple microfluidic technique was adopted to fabricate the microparticles with a high control of the nanowire concentration and in a relatively short time compared to chemical synthesis methods. The thermoresponsive microparticles were used for the remotely triggered release of Rhodamine (B). With a magnetic field of only 1 mT and 20 kHz a drug release of 6.5% and 70% was achieved in the continuous and pulsatile modes, respectively. Those release values are similar to the ones commonly obtained using superparamagnetic beads but accomplished with a magnetic field of five orders of magnitude lower power. The high efficiency is a result of the high remanent magnetization of the nanowires, which produce a large torque when exposed to a magnetic field. This causes the nanowires to vibrate, resulting in friction losses and heating. For comparison, microparticles with superparamagnetic beads were also fabricated and tested; while those worked at 73 mT and 600 kHz, no release was observed at the low field conditions. Cytotoxicity assays showed similar and high cell viability for microparticles with nanowires and beads.

  13. Highly Efficient Thermoresponsive Nanocomposite for Controlled Release Applications

    KAUST Repository

    Yassine, Omar; Zaher, Amir; Li, Erqiang; Alfadhel, Ahmed; Perez, Jose E.; Kavaldzhiev, Mincho; Contreras, Maria F.; Thoroddsen, Sigurdur T; Khashab, Niveen M.; Kosel, Jü rgen

    2016-01-01

    Highly efficient magnetic release from nanocomposite microparticles is shown, which are made of Poly (N-isopropylacrylamide) hydrogel with embedded iron nanowires. A simple microfluidic technique was adopted to fabricate the microparticles with a high control of the nanowire concentration and in a relatively short time compared to chemical synthesis methods. The thermoresponsive microparticles were used for the remotely triggered release of Rhodamine (B). With a magnetic field of only 1 mT and 20 kHz a drug release of 6.5% and 70% was achieved in the continuous and pulsatile modes, respectively. Those release values are similar to the ones commonly obtained using superparamagnetic beads but accomplished with a magnetic field of five orders of magnitude lower power. The high efficiency is a result of the high remanent magnetization of the nanowires, which produce a large torque when exposed to a magnetic field. This causes the nanowires to vibrate, resulting in friction losses and heating. For comparison, microparticles with superparamagnetic beads were also fabricated and tested; while those worked at 73 mT and 600 kHz, no release was observed at the low field conditions. Cytotoxicity assays showed similar and high cell viability for microparticles with nanowires and beads.

  14. Multiscale approaches to high efficiency photovoltaics

    Directory of Open Access Journals (Sweden)

    Connolly James Patrick

    2016-01-01

    Full Text Available While renewable energies are achieving parity around the globe, efforts to reach higher solar cell efficiencies becomes ever more difficult as they approach the limiting efficiency. The so-called third generation concepts attempt to break this limit through a combination of novel physical processes and new materials and concepts in organic and inorganic systems. Some examples of semi-empirical modelling in the field are reviewed, in particular for multispectral solar cells on silicon (French ANR project MultiSolSi. Their achievements are outlined, and the limits of these approaches shown. This introduces the main topic of this contribution, which is the use of multiscale experimental and theoretical techniques to go beyond the semi-empirical understanding of these systems. This approach has already led to great advances at modelling which have led to modelling software, which is widely known. Yet, a survey of the topic reveals a fragmentation of efforts across disciplines, firstly, such as organic and inorganic fields, but also between the high efficiency concepts such as hot carrier cells and intermediate band concepts. We show how this obstacle to the resolution of practical research obstacles may be lifted by inter-disciplinary cooperation across length scales, and across experimental and theoretical fields, and finally across materials systems. We present a European COST Action “MultiscaleSolar” kicking off in early 2015, which brings together experimental and theoretical partners in order to develop multiscale research in organic and inorganic materials. The goal of this defragmentation and interdisciplinary collaboration is to develop understanding across length scales, which will enable the full potential of third generation concepts to be evaluated in practise, for societal and industrial applications.

  15. Radiation hardened high efficiency silicon space solar cell

    International Nuclear Information System (INIS)

    Garboushian, V.; Yoon, S.; Turner, J.

    1993-01-01

    A silicon solar cell with AMO 19% Beginning of Life (BOL) efficiency is reported. The cell has demonstrated equal or better radiation resistance when compared to conventional silicon space solar cells. Conventional silicon space solar cell performance is generally ∼ 14% at BOL. The Radiation Hardened High Efficiency Silicon (RHHES) cell is thinned for high specific power (watts/kilogram). The RHHES space cell provides compatibility with automatic surface mounting technology. The cells can be easily combined to provide desired power levels and voltages. The RHHES space cell is more resistant to mechanical damage due to micrometeorites. Micro-meteorites which impinge upon conventional cells can crack the cell which, in turn, may cause string failure. The RHHES, operating in the same environment, can continue to function with a similar crack. The RHHES cell allows for very efficient thermal management which is essential for space cells generating higher specific power levels. The cell eliminates the need for electrical insulation layers which would otherwise increase the thermal resistance for conventional space panels. The RHHES cell can be applied to a space concentrator panel system without abandoning any of the attributes discussed. The power handling capability of the RHHES cell is approximately five times more than conventional space concentrator solar cells

  16. Optimization of a high efficiency FEL amplifier

    International Nuclear Information System (INIS)

    Schneidmiller, E.A.; Yurkov, M.V.

    2014-10-01

    The problem of an efficiency increase of an FEL amplifier is now of great practical importance. Technique of undulator tapering in the post-saturation regime is used at the existing X-ray FELs LCLS and SACLA, and is planned for use at the European XFEL, Swiss FEL, and PAL XFEL. There are also discussions on the future of high peak and average power FELs for scientific and industrial applications. In this paper we perform detailed analysis of the tapering strategies for high power seeded FEL amplifiers. Application of similarity techniques allows us to derive universal law of the undulator tapering.

  17. Tailored Materials for High Efficiency CIDI Engines

    Energy Technology Data Exchange (ETDEWEB)

    Grant, G.J.; Jana, S.

    2012-03-30

    The overall goal of the project, Tailored Materials for High Efficiency Compression Ignition Direct Injection (CIDI) Engines, is to enable the implementation of new combustion strategies, such as homogeneous charge compression ignition (HCCI), that have the potential to significantly increase the energy efficiency of current diesel engines and decrease fuel consumption and environmental emissions. These strategies, however, are increasing the demands on conventional engine materials, either from increases in peak cylinder pressure (PCP) or from increases in the temperature of operation. The specific objective of this project is to investigate the application of a new material processing technology, friction stir processing (FSP), to improve the thermal and mechanical properties of engine components. The concept is to modify the surfaces of conventional, low-cost engine materials. The project focused primarily on FSP in aluminum materials that are compositional analogs to the typical piston and head alloys seen in small- to mid-sized CIDI engines. Investigations have been primarily of two types over the duration of this project: (1) FSP of a cast hypoeutectic Al-Si-Mg (A356/357) alloy with no introduction of any new components, and (2) FSP of Al-Cu-Ni alloys (Alloy 339) by physically stirring-in various quantities of carbon nanotubes/nanofibers or carbon fibers. Experimental work to date on aluminum systems has shown significant increases in fatigue lifetime and stress-level performance in aluminum-silicon alloys using friction processing alone, but work to demonstrate the addition of carbon nanotubes and fibers into aluminum substrates has shown mixed results due primarily to the difficulty in achieving porosity-free, homogeneous distributions of the particulate. A limited effort to understand the effects of FSP on steel materials was also undertaken during the course of this project. Processed regions were created in high-strength, low-alloyed steels up to 0.5 in

  18. Evaluating performance of high efficiency mist eliminators

    Energy Technology Data Exchange (ETDEWEB)

    Waggoner, Charles A.; Parsons, Michael S.; Giffin, Paxton K. [Mississippi State University, Institute for Clean Energy Technology, 205 Research Blvd, Starkville, MS (United States)

    2013-07-01

    Processing liquid wastes frequently generates off gas streams with high humidity and liquid aerosols. Droplet laden air streams can be produced from tank mixing or sparging and processes such as reforming or evaporative volume reduction. Unfortunately these wet air streams represent a genuine threat to HEPA filters. High efficiency mist eliminators (HEME) are one option for removal of liquid aerosols with high dissolved or suspended solids content. HEMEs have been used extensively in industrial applications, however they have not seen widespread use in the nuclear industry. Filtering efficiency data along with loading curves are not readily available for these units and data that exist are not easily translated to operational parameters in liquid waste treatment plants. A specialized test stand has been developed to evaluate the performance of HEME elements under use conditions of a US DOE facility. HEME elements were tested at three volumetric flow rates using aerosols produced from an iron-rich waste surrogate. The challenge aerosol included submicron particles produced from Laskin nozzles and super micron particles produced from a hollow cone spray nozzle. Test conditions included ambient temperature and relative humidities greater than 95%. Data collected during testing HEME elements from three different manufacturers included volumetric flow rate, differential temperature across the filter housing, downstream relative humidity, and differential pressure (dP) across the filter element. Filter challenge was discontinued at three intermediate dPs and the filter to allow determining filter efficiency using dioctyl phthalate and then with dry surrogate aerosols. Filtering efficiencies of the clean HEME, the clean HEME loaded with water, and the HEME at maximum dP were also collected using the two test aerosols. Results of the testing included differential pressure vs. time loading curves for the nine elements tested along with the mass of moisture and solid

  19. Analysis and evaluation for practical application of photovoltaic power generation system. Analysis and evaluation for development of extra-high efficiency solar cells (fundamental research on extra-high efficiency III-V compound semiconductor tandem solar cells); Taiyoko hatsuden system jitsuyoka no tame no kaiseki hyoka. Chokokoritsu taiyo denchi no gijutsu kaihatsu no tame no kaiseki hyoka (chokokoritsu III-V zoku kagobutsu taiyo denchi gijutsu kaihatsu)

    Energy Technology Data Exchange (ETDEWEB)

    Sekikawa, T; Kawanami, H; Sakata, I; Nagai, K; Matsumoto, K; Miki, K [Electrotechnical Laboratory, Tsukuba (Japan)

    1994-12-01

    Described herein are the results of the FY1994 research program for development of extra-high efficiency III-V compound semiconductor tandem solar cells. Heteroepitaxial structures of compound semiconductors, such as GaAs, on silicon substrates are analyzed and evaluated by EXAFS, Raman and RHEED for the initial stage of the film growth and heterointerfaces. The device capable of in-situ observation of the growing surface structures during the period of heteroepitaxial film growth is introduced, to investigate the effects of rise-up and initial growth conditions on defects. The effects of atomic hydrogen on growth of a GaAs film on a silicon substrate are investigated from photoluminescence and solar cell characteristics, to confirm the effects of reducing defects. Heteroepitaxial growth of InGaP, which has the optimum band width for forming multi-junction silicon solar cells, on a silicon substrate is investigated, to find that an interfacial buffer layer is necessary to form a good film. 2 figs.

  20. High efficiency graphene coated copper based thermocells connected in series

    Science.gov (United States)

    Sindhuja, Mani; Indubala, Emayavaramban; Sudha, Venkatachalam; Harinipriya, Seshadri

    2018-04-01

    Conversion of low-grade waste heat into electricity had been studied employing single thermocell or flowcells so far. Graphene coated copper electrodes based thermocells connected in series displayed relatively high efficiency of thermal energy harvesting. The maximum power output of 49.2W/m2 for normalized cross sectional electrode area is obtained at 60ºC of inter electrode temperature difference. The relative carnot efficiency of 20.2% is obtained from the device. The importance of reducing the mass transfer and ion transfer resistance to improve the efficiency of the device is demonstrated. Degradation studies confirmed mild oxidation of copper foil due to corrosion caused by the electrolyte.

  1. High Efficiency Graphene Coated Copper Based Thermocells Connected in Series

    Directory of Open Access Journals (Sweden)

    Mani Sindhuja

    2018-04-01

    Full Text Available Conversion of low-grade waste heat into electricity had been studied employing single thermocell or flowcells so far. Graphene coated copper electrodes based thermocells connected in series displayed relatively high efficiency of thermal energy harvesting. The maximum power output of 49.2 W/m2 for normalized cross sectional electrode area is obtained at 60°C of inter electrode temperature difference. The relative carnot efficiency of 20.2% is obtained from the device. The importance of reducing the mass transfer and ion transfer resistance to improve the efficiency of the device is demonstrated. Degradation studies confirmed mild oxidation of copper foil due to corrosion caused by the electrolyte.

  2. Rigid-beam model of a high-efficiency magnicon

    International Nuclear Information System (INIS)

    Rees, D.E.; Tallerico, P.J.; Humphries, S.J. Jr.

    1993-01-01

    The magnicon is a new type of high-efficiency deflection-modulated amplifier developed at the Institute of Nuclear Physics in Novosibirsk, Russia. The prototype pulsed magnicon achieved an output power of 2.4 MW and an efficiency of 73% at 915 MHz. This paper presents the results of a rigid-beam model for a 700-MHz, 2.5-MW 82%-efficient magnicon. The rigid-beam model allows for characterization of the beam dynamics by tracking only a single electron. The magnicon design presented consists of a drive cavity; passive cavities; a pi-mode, coupled-deflection cavity; and an output cavity. It represents an optimized design. The model is fully self-consistent, and this paper presents the details of the model and calculated performance of a 2.5-MW magnicon

  3. Study on a Novel High-Efficiency Bridgeless PFC Converter

    Directory of Open Access Journals (Sweden)

    Cao Taiqiang

    2014-01-01

    Full Text Available In order to implement a high-efficiency bridgeless power factor correction converter, a new topology and operation principles of continuous conduction mode (CCM and DC steady-state character of the converter are analyzed, which show that the converter not only has bipolar-gain characteristic but also has the same characteristic as the traditional Boost converter, while the voltage transfer ratio is not related with the resonant branch parameters and switching frequency. Based on the above topology, a novel bridgeless Bipolar-Gain Pseudo-Boost PFC converter is proposed. With this converter, the diode rectifier bridge of traditional AC-DC converter is eliminated, and zero-current switching of fast recovery diode is achieved. Thus, the efficiency is improved. Next, we also propose the one-cycle control policy of this converter. Finally, experiments are provided to verify the accuracy and feasibility of the proposed converter.

  4. SiC-based High Efficiency Bidirectional Battery Converter for Smart PV Residential Systems

    DEFF Research Database (Denmark)

    Pham, Cam; Biris, Valeriu-Ciprian; Teodorescu, Remus

    2013-01-01

    Smart PV inverters are essential components of future grids. Beside conventional functionalities they can communicate with the grid, supports the grid with reactive power and with active power from internal battery storage. To maximize internal consumption, a high efficiency bidirectional DC-DC c...

  5. High efficiency stoichiometric internal combustion engine system

    Science.gov (United States)

    Winsor, Richard Edward; Chase, Scott Allen

    2009-06-02

    A power system including a stoichiometric compression ignition engine in which a roots blower is positioned in the air intake for the engine to control air flow. Air flow is decreased during part power conditions to maintain the air-fuel ratio in the combustion chamber of the engine at stoichiometric, thus enabling the use of inexpensive three-way catalyst to reduce oxides of nitrogen. The roots blower is connected to a motor generator so that when air flow is reduced, electrical energy is stored which is made available either to the roots blower to temporarily increase air flow or to the system electrical load and thus recapture energy that would otherwise be lost in reducing air flow.

  6. High-Efficient Circuits for Ternary Addition

    Directory of Open Access Journals (Sweden)

    Reza Faghih Mirzaee

    2014-01-01

    Full Text Available New ternary adders, which are fundamental components of ternary addition, are presented in this paper. They are on the basis of a logic style which mostly generates binary signals. Therefore, static power dissipation reaches its minimum extent. Extensive different analyses are carried out to examine how efficient the new designs are. For instance, the ternary ripple adder constructed by the proposed ternary half and full adders consumes 2.33 μW less power than the one implemented by the previous adder cells. It is almost twice faster as well. Due to their unique superior characteristics for ternary circuitry, carbon nanotube field-effect transistors are used to form the novel circuits, which are entirely suitable for practical applications.

  7. High efficiency, multiterawatt x-ray free electron lasers

    Directory of Open Access Journals (Sweden)

    C. Emma

    2016-02-01

    Full Text Available In this paper we present undulator magnet tapering methods for obtaining high efficiency and multiterawatt peak powers in x-ray free electron lasers (XFELs, a key requirement for enabling 3D atomic resolution single molecule imaging and nonlinear x-ray science. The peak power and efficiency of tapered XFELs is sensitive to time dependent effects, like synchrotron sideband growth. To analyze this dependence in detail we perform a comparative numerical optimization for the undulator magnetic field tapering profile including and intentionally disabling these effects. We show that the solution for the magnetic field taper profile obtained from time independent optimization does not yield the highest extraction efficiency when time dependent effects are included. Our comparative optimization is performed for a novel undulator designed specifically to obtain TW power x-ray pulses in the shortest distance: superconducting, helical, with short period and built-in strong focusing. This design reduces the length of the breaks between modules, decreasing diffraction effects, and allows using a stronger transverse electron focusing. Both effects reduce the gain length and the overall undulator length. We determine that after a fully time dependent optimization of a 100 m long Linac coherent light source-like XFEL we can obtain a maximum efficiency of 7%, corresponding to 3.7 TW peak radiation power. Possible methods to suppress the synchrotron sidebands, and further enhance the FEL peak power, up to about 6 TW by increasing the seed power and reducing the electron beam energy spread, are also discussed.

  8. A high-efficiency electromechanical battery

    Science.gov (United States)

    Post, Richard F.; Fowler, T. K.; Post, Stephen F.

    1993-03-01

    In our society there is a growing need for efficient cost-effective means for storing electrical energy. The electric auto is a prime example. Storage systems for the electric utilities, and for wind or solar power, are other examples. While electrochemical cells could in principle supply these needs, the existing E-C batteries have well-known limitations. This article addresses an alternative, the electromechanical battery (EMB). An EMB is a modular unit consisting of an evacuated housing containing a fiber-composite rotor. The rotor is supported by magnetic bearings and contains an integrally mounted permanent magnet array. This article addresses design issues for EMBs with rotors made up of nested cylinders. Issues addressed include rotational stability, stress distributions, generator/motor power and efficiency, power conversion, and cost. It is concluded that the use of EMBs in electric autos could result in a fivefold reduction (relative to the IC engine) in the primary energy input required for urban driving, with a concomitant major positive impact on our economy and on air pollution.

  9. Ultra-high Efficiency DC-DC Converter using GaN Devices

    DEFF Research Database (Denmark)

    Ramachandran, Rakesh

    2016-01-01

    properties of GaN devices can be utilized in power converters to make them more compact and highly efficient. This thesis entitled “Ultra-high Efficiency DC-DC Converter using GaN devices” focuses on achieving ultra-high conversion efficiency in an isolated dc-dc converter by the optimal utilization of Ga...... for many decades. However, the rate of improvement slowed as the silicon power materials asymptotically approached its theoretical bounds. Compared to Si, wideband gap materials such as Silicon Carbide (SiC) and Gallium Nitride (GaN) are promising semiconductors for power devices due to their superior...... in this thesis. Efficiency measurements from the hardware prototype of both the topologies are also presented in this thesis. Finally, the bidirectional operation of an optimized isolated dc-dc converter is presented. The optimized converter has achieved an ultra-high efficiency of 98.8% in both directions...

  10. High efficiency quasi-monochromatic infrared emitter

    Energy Technology Data Exchange (ETDEWEB)

    Brucoli, Giovanni; Besbes, Mondher; Benisty, Henri, E-mail: henri.benisty@institutoptique.fr; Greffet, Jean-Jacques [Laboratoire Charles Fabry, UMR 8501, Institut d’Optique, CNRS, Université Paris-Sud 11, 2, Avenue Augustin Fresnel, 91127 Palaiseau Cedex (France); Bouchon, Patrick; Haïdar, Riad [Office National d’Études et de Recherches Aérospatiales, Chemin de la Hunière, 91761 Palaiseau (France)

    2014-02-24

    Incandescent radiation sources are widely used as mid-infrared emitters owing to the lack of alternative for compact and low cost sources. A drawback of miniature hot systems such as membranes is their low efficiency, e.g., for battery powered systems. For targeted narrow-band applications such as gas spectroscopy, the efficiency is even lower. In this paper, we introduce design rules valid for very generic membranes demonstrating that their energy efficiency for use as incandescent infrared sources can be increased by two orders of magnitude.

  11. High Efficiency and Low Cost Thermal Energy Storage System

    Energy Technology Data Exchange (ETDEWEB)

    Sienicki, James J. [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Lv, Qiuping [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Moisseytsev, Anton [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Bucknor, Matthew [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division

    2017-09-29

    BgtL, LLC (BgtL) is focused on developing and commercializing its proprietary compact technology for processes in the energy sector. One such application is a compact high efficiency Thermal Energy Storage (TES) system that utilizes the heat of fusion through phase change between solid and liquid to store and release energy at high temperatures and incorporate state-of-the-art insulation to minimize heat dissipation. BgtL’s TES system would greatly improve the economics of existing nuclear and coal-fired power plants by allowing the power plant to store energy when power prices are low and sell power into the grid when prices are high. Compared to existing battery storage technology, BgtL’s novel thermal energy storage solution can be significantly less costly to acquire and maintain, does not have any waste or environmental emissions, and does not deteriorate over time; it can keep constant efficiency and operates cleanly and safely. BgtL’s engineers are experienced in this field and are able to design and engineer such a system to a specific power plant’s requirements. BgtL also has a strong manufacturing partner to fabricate the system such that it qualifies for an ASME code stamp. BgtL’s vision is to be the leading provider of compact systems for various applications including energy storage. BgtL requests that all technical information about the TES designs be protected as proprietary information. To honor that request, only non-proprietay summaries are included in this report.

  12. A High Efficiency DC-DC Converter Topology Suitable for Distributed Large Commercial and Utility Scale PV Systems

    Energy Technology Data Exchange (ETDEWEB)

    Agamy, Mohammed S; Harfman-Todorovic, Maja; Elasser, Ahmed; Steigerwald, Robert L; Sabate, Juan A; Chi, Song; McCann, Adam J; Zhang, Li; Mueller, Frank

    2012-09-01

    In this paper a DC-DC power converter for distributed photovoltaic plant architectures is presented. The proposed converter has the advantages of simplicity, high efficiency, and low cost. High efficiency is achieved by having a portion of the input PV power directly fed forward to the output without being processed by the converter. The operation of this converter also allows for a simplified maximum power point tracker design using fewer measurements

  13. A high-efficiency superconductor distributed amplifier

    Energy Technology Data Exchange (ETDEWEB)

    Herr, Q P, E-mail: quentin.herr@ngc.co [Northrop Grumman Corporation, 7323 Aviation Boulevard, Baltimore, MD 21240 (United States)

    2010-02-15

    A superconductor output amplifier that converts single-flux-quantum signals to a non-return-to-zero pattern is reported using a twelve-stage distributed amplifier configuration. The output amplitude is measured to be 1.75 mV over a wide bias current range of {+-} 12%. The bit error rate is measured using a Delta-Sigma data pattern to be less than 1 x 10{sup -9} at 10 Gb s{sup -1} per channel. Analysis of the eye diagram suggests that the actual bit error rate may be much lower. The amplifier has power efficiency of 12% neglecting the termination resistor, which may be eliminated from the circuit with a small modification. (rapid communication)

  14. Highly efficient fully transparent inverted OLEDs

    Science.gov (United States)

    Meyer, J.; Winkler, T.; Hamwi, S.; Schmale, S.; Kröger, M.; Görrn, P.; Johannes, H.-H.; Riedl, T.; Lang, E.; Becker, D.; Dobbertin, T.; Kowalsky, W.

    2007-09-01

    One of the unique selling propositions of OLEDs is their potential to realize highly transparent devices over the visible spectrum. This is because organic semiconductors provide a large Stokes-Shift and low intrinsic absorption losses. Hence, new areas of applications for displays and ambient lighting become accessible, for instance, the integration of OLEDs into the windshield or the ceiling of automobiles. The main challenge in the realization of fully transparent devices is the deposition of the top electrode. ITO is commonly used as transparent bottom anode in a conventional OLED. To obtain uniform light emission over the entire viewing angle and a low series resistance, a TCO such as ITO is desirable as top contact as well. However, sputter deposition of ITO on top of organic layers causes damage induced by high energetic particles and UV radiation. We have found an efficient process to protect the organic layers against the ITO rf magnetron deposition process of ITO for an inverted OLED (IOLED). The inverted structure allows the integration of OLEDs in more powerful n-channel transistors used in active matrix backplanes. Employing the green electrophosphorescent material Ir(ppy) 3 lead to IOLED with a current efficiency of 50 cd/A and power efficiency of 24 lm/W at 100 cd/m2. The average transmittance exceeds 80 % in the visible region. The on-set voltage for light emission is lower than 3 V. In addition, by vertical stacking we achieved a very high current efficiency of more than 70 cd/A for transparent IOLED.

  15. Highly Efficient Thermostable DSM Cellulases: Why & How?

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Manoj [DSM Innovation, Inc., San Francisco, CA (United States)

    2011-04-26

    These are the slides from this presentation. Lignocellulosic biomass is the most abundant, least expensive renewable natural biological resource for the production of biobased products and bioenergy is important for the sustainable development of human civilization in 21st century. For making the fermentable sugars from lignocellulosic biomass, a reduction in cellulase production cost, an improvement in cellulase performance, and an increase in sugar yields are all vital to reduce the processing costs of biorefineries. Improvements in specific cellulase activities for non-complexed cellulase mixtures can be implemented through cellulase engineering based on rational design or directed evolution for each cellulase component enzyme, as well as on the reconstitution of cellulase components. In this paper, we will provide DSM's efforts in cellulase research and developments and focus on limitations. Cellulase improvement strategies based on directed evolution using screening on relevant substrates, screening for higher thermal tolerance based on activity screening approaches such as continuous culture using insoluble cellulosic substrates as a powerful selection tool for enriching beneficial cellulase mutants from the large library. We will illustrate why and how thermostable cellulases are vital for economic delivery of bioproducts from cellulosic biomass using biochemical conversion approach.

  16. A high efficiency hybrid stirling-pulse tube cryocooler

    Directory of Open Access Journals (Sweden)

    Xiaotao Wang

    2015-03-01

    Full Text Available This article presented a hybrid cryocooler which combines the room temperature displacers and the pulse tube in one system. Compared with a traditional pulse tube cryocooler, the system uses the rod-less ambient displacer to recover the expansion work from the pulse tube cold end to improve the efficiency while still keeps the advantage of the pulse tube cryocooler with no moving parts at the cold region. In the meantime, dual-opposed configurations for both the compression pistons and displacers reduce the cooler vibration to a very low level. In the experiments, a lowest no-load temperature of 38.5 K has been obtained and the cooling power at 80K was 26.4 W with an input electric power of 290 W. This leads to an efficiency of 24.2% of Carnot, marginally higher than that of an ordinary pulse tube cryocooler. The hybrid configuration herein provides a very competitive option when a high efficiency, high-reliability and robust cryocooler is desired.

  17. Highly Efficient, Durable Regenerative Solid Oxide Stack, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Precision Combustion, Inc. (PCI) proposes to develop a highly efficient regenerative solid oxide stack design. Novel structural elements allow direct internal...

  18. FY 1992 report on the results of the R and D of advanced function creation processing technology. Development of technology to create high efficiency power generation use members; 1992 nendo senshin kino soshutsu kako gijutsu no kenkyu kaihatsu seika hokokusho. Kokoritsu hatsuden'yo buzai sosei gijutsu kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1993-03-01

    The paper described the FY 1992 results of the technology to create high efficiency power generation use members. To enhance characteristics of super-high property permanent magnet up to the theoretical level, the development was proposed of a technology to control the size/configuration of micro crystal phase in association with the crystallization of alloy amorphous. For the development of environmental purification use high functional catalysts, a refining method using laser excitation was studied. The observation was also made of molecular adsorption on the Pd thin film catalyst prepared by RF sputtering. The multi-source excitation plasma CVD was proposed which was film-formed by exciting plasma as raw gas independently for each component and supplying it to the substrate of which the periphery was separately controlled. The paper also described the development of technology for ion/light combined assist ultra-thin film production for development of gas turbine combustion sensor. The study was also made of the synthesis of higher-order structure controlled high functional organic materials using the electrode interface combined field which is composed of electrode reaction/high grade photon/extreme magnetic field. In the development of the higher-order structure control technology using the photon combined reaction field, studies were made of the photo reaction film formation technology, the basic film formation technology in the combined reaction field, and the molecular orientation technology. (NEDO)

  19. FY 1993 report on the results of the R and D of advanced function creation processing technology. Development of technology to create high efficiency power generation use members; 1993 nendo senshin kino soshutsu kako gijutsu no kenkyu kaihatsu seika hokokusho. Kokoritsu hatsuden'yo buzai sosei gijutsu kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-03-01

    The paper described the FY 1993 results of the technology to create high efficiency power generation use members. A processing method was proposed in which to manifest magnetic characteristics up to the theoretical value level, crystallization of magnetic alloy amorphous was controlled and size/configuration of precipitated micro-fine crystals are made ideal. For the development of environmental purification use high functional catalysts, experiments were conducted on the heightening of purity of materials. Namely, by the two wavelength two stage excitation method using color laser, atomic beams of the material metal emitted by electronic beam evaporating source are photo-excited up near the ionization level. These are separated from the non-ionized components by electrostatic field application, and only the ionized atoms are vapor-deposited on substrate. The separation accuracy was good. Plasma excitation of raw gas was done independently for every component, and the multi-source excitation plasma CVD was proposed which is film-formed on the substrate of which the periphery was separately controlled. The synthesis method was considered of higher-order structure control high functional organic materials which are composed of electrode reaction/high grade photon/extreme magnetic field. Study was made of complex reaction field application film-forming/molecular orientation technology using a small test device. (NEDO)

  20. FY 1993 report on the results of the R and D of advanced function creation processing technology. Development of technology to create high efficiency power generation use members; 1993 nendo senshin kino soshutsu kako gijutsu no kenkyu kaihatsu seika hokokusho. Kokoritsu hatsuden'yo buzai sosei gijutsu kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-03-01

    The paper described the FY 1993 results of the technology to create high efficiency power generation use members. A processing method was proposed in which to manifest magnetic characteristics up to the theoretical value level, crystallization of magnetic alloy amorphous was controlled and size/configuration of precipitated micro-fine crystals are made ideal. For the development of environmental purification use high functional catalysts, experiments were conducted on the heightening of purity of materials. Namely, by the two wavelength two stage excitation method using color laser, atomic beams of the material metal emitted by electronic beam evaporating source are photo-excited up near the ionization level. These are separated from the non-ionized components by electrostatic field application, and only the ionized atoms are vapor-deposited on substrate. The separation accuracy was good. Plasma excitation of raw gas was done independently for every component, and the multi-source excitation plasma CVD was proposed which is film-formed on the substrate of which the periphery was separately controlled. The synthesis method was considered of higher-order structure control high functional organic materials which are composed of electrode reaction/high grade photon/extreme magnetic field. Study was made of complex reaction field application film-forming/molecular orientation technology using a small test device. (NEDO)

  1. FY 1992 report on the results of the R and D of advanced function creation processing technology. Development of technology to create high efficiency power generation use members; 1992 nendo senshin kino soshutsu kako gijutsu no kenkyu kaihatsu seika hokokusho. Kokoritsu hatsuden'yo buzai sosei gijutsu kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1993-03-01

    The paper described the FY 1992 results of the technology to create high efficiency power generation use members. To enhance characteristics of super-high property permanent magnet up to the theoretical level, the development was proposed of a technology to control the size/configuration of micro crystal phase in association with the crystallization of alloy amorphous. For the development of environmental purification use high functional catalysts, a refining method using laser excitation was studied. The observation was also made of molecular adsorption on the Pd thin film catalyst prepared by RF sputtering. The multi-source excitation plasma CVD was proposed which was film-formed by exciting plasma as raw gas independently for each component and supplying it to the substrate of which the periphery was separately controlled. The paper also described the development of technology for ion/light combined assist ultra-thin film production for development of gas turbine combustion sensor. The study was also made of the synthesis of higher-order structure controlled high functional organic materials using the electrode interface combined field which is composed of electrode reaction/high grade photon/extreme magnetic field. In the development of the higher-order structure control technology using the photon combined reaction field, studies were made of the photo reaction film formation technology, the basic film formation technology in the combined reaction field, and the molecular orientation technology. (NEDO)

  2. HIGH EFFICIENCY DESULFURIZATION OF SYNTHESIS GAS

    Energy Technology Data Exchange (ETDEWEB)

    Kwang-Bok Yi; Anirban Mukherjee; Elizabeth J. Podlaha; Douglas P. Harrison

    2004-03-01

    reducing gases for extended time periods. H{sub 2}S concentrations were reduced to levels approaching the minimum detectable limit of the PFPD detector, approximately 100 ppbv for time periods corresponding to as much as 60% sorbent sulfidation. The critical test of the sorbents was their performance when the reducing power of the feed gas was decreased by the addition of CO{sub 2} as an oxidant. While sub-ppmv levels of H{sub 2}S were still achieved using both CeO{sub 2} and CeO{sub 2}-ZrO{sub 2} sorbents when the feed gas contained as much as 1% CO{sub 2}, the duration of the prebreakthrough time decreased as the CO{sub 2} concentration increased.

  3. 40 CFR 761.71 - High efficiency boilers.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false High efficiency boilers. 761.71... PROHIBITIONS Storage and Disposal § 761.71 High efficiency boilers. (a) To burn mineral oil dielectric fluid containing a PCB concentration of ≥50 ppm, but boiler shall comply with the following...

  4. High efficiency nebulization for helium inductively coupled plasma mass spectrometry

    International Nuclear Information System (INIS)

    Jorabchi, Kaveh; McCormick, Ryan; Levine, Jonathan A.; Liu Huiying; Nam, S.-H.; Montaser, Akbar

    2006-01-01

    A pneumatically-driven, high efficiency nebulizer is explored for helium inductively coupled plasma mass spectrometry. The aerosol characteristics and analyte transport efficiencies of the high efficiency nebulizer for nebulization with helium are measured and compared to the results obtained with argon. Analytical performance indices of the helium inductively coupled plasma mass spectrometry are evaluated in terms of detection limits and precision. The helium inductively coupled plasma mass spectrometry detection limits obtained with the high efficiency nebulizer at 200 μL/min are higher than those achieved with the ultrasonic nebulizer consuming 2 mL/min solution, however, precision is generally better with high efficiency nebulizer (1-4% vs. 3-8% with ultrasonic nebulizer). Detection limits with the high efficiency nebulizer at 200 μL/min solution uptake rate approach those using ultrasonic nebulizer upon efficient desolvation with a heated spray chamber followed by a Peltier-cooled multipass condenser

  5. High Efficiency Non-isolated Three Port DC-DC Converter for PV-Battery Systems

    DEFF Research Database (Denmark)

    Tomas Manez, Kevin; Anthon, Alexander; Zhang, Zhe

    2016-01-01

    This paper presents a nonisolated Three Port Converter (TPC) with a unidirectional port for photovoltaic (PV) panels and a bidirectional port for energy storage. With the proposed topology single power conversion is performed between each port, so high efficiencies are obtained. A theoretical...

  6. Ultra-high efficiency, fast graphene micro-heater on silicon

    DEFF Research Database (Denmark)

    Yan, Siqi; Zhu, Xiaolong; Frandsen, Lars Hagedorn

    2017-01-01

    We demonstrate an ultra-high efficiency and fast graphene microheater on silicon photonic crystal waveguide. By taking advantage of slow-light effect, a tuning efficiency of 1.07 nm/mW and power consumption per free spectral range of 3.99 mW. A fast rise and decay times (10% to 90%) of only 750 ns...

  7. High efficiency battery converter with SiC devices for residential PV systems

    DEFF Research Database (Denmark)

    Pham, Cam; Teodorescu, Remus; Kerekes, Tamas

    2013-01-01

    The demand for high efficiency and higher power density is a challenge for Si-based semiconductors due to the physical characteristics of material. These can be overcome by employing wide-band-gap materials like SiC. This paper compares a second generator SiC MOSFETs against a normally-on Trench...

  8. Highly efficient tandem polymer solar cells with a photovoltaic response in the visible light range.

    Science.gov (United States)

    Zheng, Zhong; Zhang, Shaoqing; Zhang, Maojie; Zhao, Kang; Ye, Long; Chen, Yu; Yang, Bei; Hou, Jianhui

    2015-02-18

    Highly efficient polymer solar cells with a tandem structure are fabricated by using two excellent photovoltaic polymers and a highly transparent intermediate recombination layer. Power conversion -efficiencies over 10% can be realized with a photovoltaic response within 800 nm. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Highly Efficient and Reproducible Nonfullerene Solar Cells from Hydrocarbon Solvents

    KAUST Repository

    Wadsworth, Andrew; Ashraf, Raja; Abdelsamie, Maged; Pont, Sebastian; Little, Mark; Moser, Maximilian; Hamid, Zeinab; Neophytou, Marios; Zhang, Weimin; Amassian, Aram; Durrant, James R.; Baran, Derya; McCulloch, Iain

    2017-01-01

    With chlorinated solvents unlikely to be permitted for use in solution-processed organic solar cells in industry, there must be a focus on developing nonchlorinated solvent systems. Here we report high-efficiency devices utilizing a low-bandgap donor polymer (PffBT4T-2DT) and a nonfullerene acceptor (EH-IDTBR) from hydrocarbon solvents and without using additives. When mesitylene was used as the solvent, rather than chlorobenzene, an improved power conversion efficiency (11.1%) was achieved without the need for pre- or post-treatments. Despite altering the processing conditions to environmentally friendly solvents and room-temperature coating, grazing incident X-ray measurements confirmed that active layers processed from hydrocarbon solvents retained the robust nanomorphology obtained with hot-processed chlorinated solvents. The main advantages of hydrocarbon solvent-processed devices, besides the improved efficiencies, were the reproducibility and storage lifetime of devices. Mesitylene devices showed better reproducibility and shelf life up to 4000 h with PCE dropping by only 8% of its initial value.

  10. High-efficiency ballistic electrostatic generator using microdroplets

    Science.gov (United States)

    Xie, Yanbo; Bos, Diederik; de Vreede, Lennart J.; de Boer, Hans L.; van der Meulen, Mark-Jan; Versluis, Michel; Sprenkels, Ad J.; van den Berg, Albert; Eijkel, Jan C. T.

    2014-04-01

    The strong demand for renewable energy promotes research on novel methods and technologies for energy conversion. Microfluidic systems for energy conversion by streaming current are less known to the public, and the relatively low efficiencies previously obtained seemed to limit the further applications of such systems. Here we report a microdroplet-based electrostatic generator operating by an acceleration-deceleration cycle (‘ballistic’ conversion), and show that this principle enables both high efficiency and compact simple design. Water is accelerated by pumping it through a micropore to form a microjet breaking up into fast-moving charged droplets. Droplet kinetic energy is converted to electrical energy when the charged droplets decelerate in the electrical field that forms between membrane and target. We demonstrate conversion efficiencies of up to 48%, a power density of 160 kW m-2 and both high- (20 kV) and low- (500 V) voltage operation. Besides offering striking new insights, the device potentially opens up new perspectives for low-cost and robust renewable energy conversion.

  11. Highly Efficient and Reproducible Nonfullerene Solar Cells from Hydrocarbon Solvents

    KAUST Repository

    Wadsworth, Andrew

    2017-06-01

    With chlorinated solvents unlikely to be permitted for use in solution-processed organic solar cells in industry, there must be a focus on developing nonchlorinated solvent systems. Here we report high-efficiency devices utilizing a low-bandgap donor polymer (PffBT4T-2DT) and a nonfullerene acceptor (EH-IDTBR) from hydrocarbon solvents and without using additives. When mesitylene was used as the solvent, rather than chlorobenzene, an improved power conversion efficiency (11.1%) was achieved without the need for pre- or post-treatments. Despite altering the processing conditions to environmentally friendly solvents and room-temperature coating, grazing incident X-ray measurements confirmed that active layers processed from hydrocarbon solvents retained the robust nanomorphology obtained with hot-processed chlorinated solvents. The main advantages of hydrocarbon solvent-processed devices, besides the improved efficiencies, were the reproducibility and storage lifetime of devices. Mesitylene devices showed better reproducibility and shelf life up to 4000 h with PCE dropping by only 8% of its initial value.

  12. A High Efficiency Li-Ion Battery LDO-Based Charger for Portable Application

    Directory of Open Access Journals (Sweden)

    Youssef Ziadi

    2015-01-01

    Full Text Available This paper presents a high efficiency Li-ion battery LDO-based charger IC which adopted a three-mode control: trickle constant current, fast constant current, and constant voltage modes. The criteria of the proposed Li-ion battery charger, including high accuracy, high efficiency, and low size area, are of high importance. The simulation results provide the trickle current of 116 mA, maximum charging current of 448 mA, and charging voltage of 4.21 V at the power supply of 4.8–5 V, using 0.18 μm CMOS technology.

  13. High-efficiency FEL with Bragg resonator driven by linear induction accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Ginzburg, N S; Kaminskij, A A; Kaminskij, A K; Peskov, N Yu; Sedykh, S N; Sergeev, A P; Sergeev, A S [Russian Academy of Sciences, Nizhny Novgorod (Russian Federation). Inst. of Applied Physics

    1997-12-31

    A narrow-band high-efficiency FEL-oscillator with a Bragg resonator was constructed based on a linear induction accelerator which formed a 1 MeV, 200 A, 200 ns electron beam. At the frequency of 31 GHz, radiation with a power of 31 MW and efficiency of 25% was measured. A high efficiency and a narrow width of the spectrum were achieved owing to the selective properties of the Bragg resonator in combination with the high quality of the helical electron beam formed in the reversed guide field regime. (author). 3 figs., 3 refs.

  14. High-efficiency diode-pumped femtosecond Yb:YAG ceramic laser

    DEFF Research Database (Denmark)

    Zhou, Binbin; Wei, Z.Y.; Zou, Y.W.

    2010-01-01

    A highly efficient diode-end-pumped femtosecond Yb:yttrium aluminum garnet (YAG) ceramic laser was demonstrated. Pumped by a 968 nm fiber-coupled diode laser, 1.9 W mode-locked output power at a repetition rate of 64.27 MHz was obtained with 3.5 W absorbed pump power, corresponding to a slope...... efficiency of 76%. Our measurement showed that the pulse duration was 418 fs with the central wavelength of 1048 nm....

  15. High Efficiency Lighting with Integrated Adaptive Control (HELIAC), Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed project is the continued development of the High Efficiency Lighting with Integrated Adaptive Control (HELIAC) system. Solar radiation is not a viable...

  16. High Efficiency Lighting with Integrated Adaptive Control (HELIAC), Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The innovation of the proposed project is the development of High Efficiency Lighting with Integrated Adaptive Control (HELIAC) systems to drive plant growth. Solar...

  17. High Efficiency S-Band 20 Watt Amplifier

    Data.gov (United States)

    National Aeronautics and Space Administration — This project includes the design and build of a prototype 20 W, high efficiency, S-Band amplifier.   The design will incorporate the latest semiconductor technology,...

  18. Process development for high-efficiency silicon solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Gee, J.M.; Basore, P.A.; Buck, M.E.; Ruby, D.S.; Schubert, W.K.; Silva, B.L.; Tingley, J.W.

    1991-12-31

    Fabrication of high-efficiency silicon solar cells in an industrial environment requires a different optimization than in a laboratory environment. Strategies are presented for process development of high-efficiency silicon solar cells, with a goal of simplifying technology transfer into an industrial setting. The strategies emphasize the use of statistical experimental design for process optimization, and the use of baseline processes and cells for process monitoring and quality control. 8 refs.

  19. The photonic nanowire: A highly efficient single-photon source

    DEFF Research Database (Denmark)

    Gregersen, Niels

    2014-01-01

    The photonic nanowire represents an attractive platform for a quantum light emitter. However, careful optical engineering using the modal method, which elegantly allows access to all relevant physical parameters, is crucial to ensure high efficiency.......The photonic nanowire represents an attractive platform for a quantum light emitter. However, careful optical engineering using the modal method, which elegantly allows access to all relevant physical parameters, is crucial to ensure high efficiency....

  20. High-efficiency airfoil rudders applied to submarines

    Directory of Open Access Journals (Sweden)

    ZHOU Yimei

    2017-03-01

    Full Text Available Modern submarine design puts forward higher and higher requirements for control surfaces, and this creates a requirement for designers to constantly innovate new types of rudder so as to improve the efficiency of control surfaces. Adopting the high-efficiency airfoil rudder is one of the most effective measures for improving the efficiency of control surfaces. In this paper, we put forward an optimization method for a high-efficiency airfoil rudder on the basis of a comparative analysis of the various strengths and weaknesses of the airfoil, and the numerical calculation method is adopted to analyze the influence rule of the hydrodynamic characteristics and wake field by using the high-efficiency airfoil rudder and the conventional NACA rudder comparatively; at the same time, a model load test in a towing tank was carried out, and the test results and simulation calculation obtained good consistency:the error between them was less than 10%. The experimental results show that the steerage of a high-efficiency airfoil rudder is increased by more than 40% when compared with the conventional rudder, but the total resistance is close:the error is no more than 4%. Adopting a high-efficiency airfoil rudder brings much greater lifting efficiency than the total resistance of the boat. The results show that high-efficiency airfoil rudder has obvious advantages for improving the efficiency of control, giving it good application prospects.

  1. High efficiency diffractive grating coupler based on transferred silicon nanomembrane overlay on photonic waveguide

    Energy Technology Data Exchange (ETDEWEB)

    Saha, Tapas Kumar; Zhou Weidong [University of Texas at Arlington, Department of Electrical Engineering, NanoFAB Center, Arlington, TX 76019-0072 (United States)

    2009-04-21

    We report here the design of a new type of high efficiency grating coupler, based on single crystalline Si nanomembrane overlay and stacking. Such high efficiency diffractive grating couplers are designed for the purpose of coupling light between single mode fibres and nanophotonic waveguides, and for the coupling between multiple photonic interconnect layers for compact three-dimensional vertical integration. Two-dimensional model simulation based on eigenmode expansion shows a diffractive power-up efficiency of 81% and a fibre coupling efficiency of 64%. With nanomembrane stacking, it is feasible to integrate the side-distributed Bragg reflector and bottom reflector, which can lead to the diffractive power-up efficiency and the fibre coupling efficiency of 97% and 73.5%, respectively. For a negatively detuned coupler, the bottom reflector is not needed, and the diffractive power-up efficiency can reach 98% over a large spectral range. The device is extremely tolerant to fabrication errors.

  2. Progress of OLED devices with high efficiency at high luminance

    Science.gov (United States)

    Nguyen, Carmen; Ingram, Grayson; Lu, Zhenghong

    2014-03-01

    Organic light emitting diodes (OLEDs) have progressed significantly over the last two decades. For years, OLEDs have been promoted as the next generation technology for flat panel displays and solid-state lighting due to their potential for high energy efficiency and dynamic range of colors. Although high efficiency can readily be obtained at low brightness levels, a significant decline at high brightness is commonly observed. In this report, we will review various strategies for achieving highly efficient phosphorescent OLED devices at high luminance. Specifically, we will provide details regarding the performance and general working principles behind each strategy. We will conclude by looking at how some of these strategies can be combined to produce high efficiency white OLEDs at high brightness.

  3. Compact and high-efficiency device for Raman scattering measurement using optical fibers.

    Science.gov (United States)

    Mitsui, Tadashi

    2014-11-01

    We describe the design and development of a high-efficiency optical measurement device for operation within the small bore of a high-power magnet at low temperature. For the high-efficiency measurement of light emitted from this small region, we designed a compact confocal optics with lens focusing and tilting systems, and used a piezodriven translation stage that allows micron-scale focus control of the sample position. We designed a measurement device that uses 10 m-long optical fibers in order to avoid the influence of mechanical vibration and magnetic field leakage of high-power magnets, and we also describe a technique for minimizing the fluorescence signal of optical fibers. The operation of the device was confirmed by Raman scattering measurements of monolayer graphene on quartz glass with a high signal-to-noise ratio.

  4. The Mechanism of Burn-in Loss in a High Efficiency Polymer Solar Cell

    KAUST Repository

    Peters, Craig H.

    2011-10-11

    Degradation in a high efficiency polymer solar cell is caused by the formation of states in the bandgap. These states increase the energetic disorder in the system. The power conversion efficiency loss does not occur when current is run through the device in the dark but occurs when the active layer is photo-excited. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. High Efficiency Non-isolated Three Port DC-DC Converter for PV-Battery Systems

    OpenAIRE

    Tomas Manez, Kevin; Anthon, Alexander; Zhang, Zhe; Ouyang, Ziwei; Franke, Toke

    2016-01-01

    This paper presents a nonisolated Three Port Converter (TPC) with a unidirectional port for photovoltaic (PV) panels and a bidirectional port for energy storage. With the proposed topology single power conversion is performed between each port, so high efficiencies are obtained. A theoretical analysis is carried out to analyze all operating modes and design considerations with the main equations are given. A 4kW laboratory prototype is developed and tested under all operatingconditions. Resul...

  6. Highly-efficient, flexible piezoelectric PZT thin film nanogenerator on plastic substrates.

    Science.gov (United States)

    Park, Kwi-Il; Son, Jung Hwan; Hwang, Geon-Tae; Jeong, Chang Kyu; Ryu, Jungho; Koo, Min; Choi, Insung; Lee, Seung Hyun; Byun, Myunghwan; Wang, Zhong Lin; Lee, Keon Jae

    2014-04-23

    A highly-efficient, flexible piezoelectric PZT thin film nanogenerator is demonstrated using a laser lift-off (LLO) process. The PZT thin film nanogenerator harvests the highest output performance of ∼200 V and ∼150 μA·cm(-2) from regular bending motions. Furthermore, power sources generated from a PZT thin film nanogenerator, driven by slight human finger bending motions, successfully operate over 100 LEDs. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. High-efficiency electric motors: An analysis of a feasible tariff policy for Brazil

    International Nuclear Information System (INIS)

    Paiva Delgado, M.A. de; Tolmasquim, M.T.

    1997-01-01

    The main objective is to calculate an average value for an electricity tariff which will facilitate the introduction of high-efficiency electric motors in the production sector. Two computational models will be developed for technical-economic evaluation to assess economic attractiveness by calculating feasible average electricity tariffs in order to create a market for substitution of standard motors by new high-efficiency models (Purchase Decision Model) as well as to determine if retrofitting of standard installed motors by others with high-efficiency characteristics is viable, and, if so, to specify the optimum timing for such substitution (Substitution Decision Model). It should be noted that the Purchase Decision Model takes into account power factor adjustment and the Substitution Decision Model incorporates considerations as to reduction in the electromechanical performance of operating motors. Results indicate that even where average electricity tariffs are low, as in Brazil, high-efficiency motors are economically attractive compared to standard motors. There is an obvious need for complementary instruments to assist massive market penetration

  8. Design Strategies for Ultra-high Efficiency Photovoltaics

    Science.gov (United States)

    Warmann, Emily Cathryn

    While concentrator photovoltaic cells have shown significant improvements in efficiency in the past ten years, once these cells are integrated into concentrating optics, connected to a power conditioning system and deployed in the field, the overall module efficiency drops to only 34 to 36%. This efficiency is impressive compared to conventional flat plate modules, but it is far short of the theoretical limits for solar energy conversion. Designing a system capable of achieving ultra high efficiency of 50% or greater cannot be achieved by refinement and iteration of current design approaches. This thesis takes a systems approach to designing a photovoltaic system capable of 50% efficient performance using conventional diode-based solar cells. The effort began with an exploration of the limiting efficiency of spectrum splitting ensembles with 2 to 20 sub cells in different electrical configurations. Incorporating realistic non-ideal performance with the computationally simple detailed balance approach resulted in practical limits that are useful to identify specific cell performance requirements. This effort quantified the relative benefit of additional cells and concentration for system efficiency, which will help in designing practical optical systems. Efforts to improve the quality of the solar cells themselves focused on the development of tunable lattice constant epitaxial templates. Initially intended to enable lattice matched multijunction solar cells, these templates would enable increased flexibility in band gap selection for spectrum splitting ensembles and enhanced radiative quality relative to metamorphic growth. The III-V material family is commonly used for multijunction solar cells both for its high radiative quality and for the ease of integrating multiple band gaps into one monolithic growth. The band gap flexibility is limited by the lattice constant of available growth templates. The virtual substrate consists of a thin III-V film with the desired

  9. A nuclear standard high-efficiency adsorber for iodine

    International Nuclear Information System (INIS)

    Wang Jianmin; Qian Yinge

    1988-08-01

    The structure of a nuclear standard high-efficiency adsorber, adsorbent and its performance are introduced. The performance and structure were compared with the same kind product of other firms. The results show that the leakage rate is less than 0.005%

  10. Optimization of high-efficiency components; Optimieren auf hohem Niveau

    Energy Technology Data Exchange (ETDEWEB)

    Neumann, Eva

    2009-07-01

    High efficiency is a common feature of modern current inverters and is not a unique selling proposition. Other factors that influence the buyer's decision are cost reduction, reliability and service, optimum grid integration, and the challenges of the competitive thin film technology. (orig.)

  11. Orion, a high efficiency 4π neutron detector

    International Nuclear Information System (INIS)

    Crema, E.; Piasecki, E.; Wang, X.M.; Doubre, H.; Galin, J.; Guerreau, D.; Pouthas, J.; Saint-Laurent, F.

    1990-01-01

    In intermediate energy heavy ion collisions the multiplicity of emitted neutrons is strongly connected to energy dissipation and to impact parameter. We present the 4π detector ORION, a high efficiency liquid scintillator detector which permits to get information on the multiplicity of neutrons measured event-wise and on the spatial distribution of these neutrons [fr

  12. High efficiency hydrodynamic DNA fragmentation in a bubbling system

    NARCIS (Netherlands)

    Li, Lanhui; Jin, Mingliang; Sun, Chenglong; Wang, Xiaoxue; Xie, Shuting; Zhou, Guofu; Van Den Berg, Albert; Eijkel, Jan C.T.; Shui, Lingling

    2017-01-01

    DNA fragmentation down to a precise fragment size is important for biomedical applications, disease determination, gene therapy and shotgun sequencing. In this work, a cheap, easy to operate and high efficiency DNA fragmentation method is demonstrated based on hydrodynamic shearing in a bubbling

  13. High efficiency confinement mode by electron cyclotron heating

    International Nuclear Information System (INIS)

    Funahashi, Akimasa

    1987-01-01

    In the medium size nuclear fusion experiment facility JFT-2M in the Japan Atomic Energy Research Institute, the research on the high efficiency plasma confinement mode has been advanced, and in the experiment in June, 1987, the formation of a high efficiency confinement mode was successfully controlled by electron cyclotron heating, for the first time in the world. This result further advanced the control of the formation of a high efficiency plasma confinement mode and the elucidation of the physical mechanism of that mode, and promoted the research and development of the plasma heating by electron cyclotron heating. In this paper, the recent results of the research on a high efficiency confinement mode at the JFT-2M are reported, and the role of the JFT-2M and the experiment on the improvement of core plasma performance are outlined. Now the plasma temperature exceeding 100 million deg C has been attained in large tokamaks, and in medium size facilities, the various measures for improving confinement performance are to be brought forth and their scientific basis is elucidated to assist large facilities. The JFT-2M started the operation in April, 1983, and has accumulated the results smoothly since then. (Kako, I.)

  14. Super Boiler: First Generation, Ultra-High Efficiency Firetube Boiler

    Energy Technology Data Exchange (ETDEWEB)

    None

    2006-06-01

    This factsheet describes a research project whose goal is to develop and demonstrate a first-generation ultra-high-efficiency, ultra-low emissions, compact gas-fired package boiler (Super Boiler), and formulate a long-range RD&D plan for advanced boiler technology out to the year 2020.

  15. High-efficient solar cells with porous silicon

    International Nuclear Information System (INIS)

    Migunova, A.A.

    2002-01-01

    It has been shown that the porous silicon is multifunctional high-efficient coating on silicon solar cells, modifies its surface and combines in it self antireflection and passivation properties., The different optoelectronic effects in solar cells with porous silicon were considered. The comparative parameters of uncovered photodetectors also solar cells with porous silicon and other coatings were resulted. (author)

  16. 3rd symposium on high-efficiency boiler technology: potential, performance, shortcomings of natural gas fuelled high-efficiency boilers

    International Nuclear Information System (INIS)

    1993-01-01

    The brochure contains abstracts of the papers presented at the symposium. The potential, performance and marketing problems of natural gas high-efficiency boiler systems are outlined, and new ideas are presented for gas utilities, producers of appliances, fitters, and chimneysweeps. 13 papers are available as separate regards in this database. (HW) [de

  17. Impedance Matching Antenna-Integrated High-Efficiency Energy Harvesting Circuit

    Science.gov (United States)

    Shinki, Yuharu; Shibata, Kyohei; Mansour, Mohamed

    2017-01-01

    This paper describes the design of a high-efficiency energy harvesting circuit with an integrated antenna. The circuit is composed of series resonance and boost rectifier circuits for converting radio frequency power into boosted direct current (DC) voltage. The measured output DC voltage is 5.67 V for an input of 100 mV at 900 MHz. Antenna input impedance matching is optimized for greater efficiency and miniaturization. The measured efficiency of this antenna-integrated energy harvester is 60% for −4.85 dBm input power and a load resistance equal to 20 kΩ at 905 MHz. PMID:28763043

  18. Impedance Matching Antenna-Integrated High-Efficiency Energy Harvesting Circuit

    Directory of Open Access Journals (Sweden)

    Yuharu Shinki

    2017-08-01

    Full Text Available This paper describes the design of a high-efficiency energy harvesting circuit with an integrated antenna. The circuit is composed of series resonance and boost rectifier circuits for converting radio frequency power into boosted direct current (DC voltage. The measured output DC voltage is 5.67 V for an input of 100 mV at 900 MHz. Antenna input impedance matching is optimized for greater efficiency and miniaturization. The measured efficiency of this antenna-integrated energy harvester is 60% for −4.85 dBm input power and a load resistance equal to 20 kΩ at 905 MHz.

  19. Impedance Matching Antenna-Integrated High-Efficiency Energy Harvesting Circuit.

    Science.gov (United States)

    Shinki, Yuharu; Shibata, Kyohei; Mansour, Mohamed; Kanaya, Haruichi

    2017-08-01

    This paper describes the design of a high-efficiency energy harvesting circuit with an integrated antenna. The circuit is composed of series resonance and boost rectifier circuits for converting radio frequency power into boosted direct current (DC) voltage. The measured output DC voltage is 5.67 V for an input of 100 mV at 900 MHz. Antenna input impedance matching is optimized for greater efficiency and miniaturization. The measured efficiency of this antenna-integrated energy harvester is 60% for -4.85 dBm input power and a load resistance equal to 20 kΩ at 905 MHz.

  20. Highly efficient white top-emitting organic light-emitting diodes with forward directed light emission

    Energy Technology Data Exchange (ETDEWEB)

    Freitag, Patricia; Reineke, Sebastian; Furno, Mauro; Luessem, Bjoern; Leo, Karl [Institut fuer Angewandte Photophysik, TU Dresden (Germany)

    2010-07-01

    The demand for highly efficient and energy saving illumination has increased considerably during the last decades. Organic light emitting diodes (OLEDs) are promising candidates for future lighting technologies. They offer high efficiency along with excellent color quality, allowing substantially lower power consumption than traditional illuminants. Recently, especially top-emitting devices have attracted high interest due to their compatibility with opaque substrates like metal sheets. In this contribution, we demonstrate top-emitting OLEDs with white emission spectra employing a multilayer hybrid cavity structure with two highly efficient phosphorescent emitter materials for orange-red (Ir(MDQ)2(acac)) and green (Ir(ppy)3) emission as well as the stable fluorescent blue emitter TBPe. To improve the OLED performance and modify the color quality, two different electron blocking layers and anode material combinations are tested. Compared to Lambertian emission, our devices show considerably enhanced forward emission, which is preferred for most lighting applications. Besides broadband emission and angle independent emission maxima, power efficiencies of 13.3 lm/W at 3 V and external quantum efficiencies of 5.3% are achieved. The emission shows excellent CIE coordinates of (0.420,0.407) at approx. 1000 cd/m{sup 2} and color rendering indices up to 77.

  1. Perovskite Solar Cells for High-Efficiency Tandems

    Energy Technology Data Exchange (ETDEWEB)

    McGehee, Michael [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Buonassisi, Tonio [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)

    2017-09-30

    organic cation evolution and moisture penetration to overcome the often-reported thermal and environmental instability of metal halide perovskites. Previous perovskite-containing tandems utilized molybdenum oxide (MoOx) as a sputter buffer layer, but this has raised concerns over long-term stability, as the iodide in the perovskite can chemically react with MoOx. Mixed-cation perovskite solar cells have consistently outperformed their single-cation counterparts. The first perovskite device to exceed 20% PCE was fabricated with a mixture of methylammonium (MA) and formamidinium (FA). Recent reports have shown promising results with the introduction of cesium mixtures, enabling high efficiencies with improved photo-, moisture, and thermal stability. The increased moisture and thermal stability are especially important as they broaden the parameter space for processing on top of the perovskite, enabling the deposition of metal oxide contacts through atomic layer deposition (ALD) or chemical vapor deposition (CVD) that may require elevated temperatures or water as a counter reagent. Both titanium dioxide (TiO2) and tin oxide (SnO2) have consistently proven to be effective electron-selective contacts for perovskite solar cells and both can be deposited via ALD at temperatures below 150 °C. We introduced a bilayer of SnO2 and zinc tin oxide (ZTO) that can be deposited by either low-temperature ALD or pulsed-CVD as a window layer with minimal parasitic absorption, efficient electron extraction, and sufficient buffer properties to prevent the organic and perovskite layers from damage during the subsequent sputter deposition of a transparent ITO electrode. We explored pulsed-CVD as a modified ALD process with a continual, rather than purely step-wise, growth component in order to considerably reduce the process time of the SnO2 deposition process and minimize potential perovskite degradation. These layers, when

  2. The high efficiency steel filters for nuclear air cleaning

    International Nuclear Information System (INIS)

    Bergman, W.; Larsen, G.; Lopez, R.; Williams, K.; Violet, C.

    1990-08-01

    We have, in cooperation with industry, developed high-efficiency filters made from sintered stainless-steel fibers for use in several air-cleaning applications in the nuclear industry. These filters were developed to overcome the failure modes in present high-efficiency particulate air (HEPA) filters. HEPA filters are made from glass paper and glue, and they may fail when they get hot or wet and when they are overpressured. In developing our steel filters, we first evaluated the commercially available stainless-steel filter media made from sintered powder and sintered fiber. The sintered-fiber media performed much better than sintered-powder media, and the best media had the smallest fiber diameter. Using the best media, we then built prototype filters for venting compressed gases and evaluated them in our automated filter tester. 12 refs., 20 figs

  3. High efficiency steel filters for nuclear air cleaning

    International Nuclear Information System (INIS)

    Bergman, W.; Conner, J.; Larsen, G.; Lopez, R.; Turner, C.; Vahla, G.; Violet, C.; Williams, K.

    1991-01-01

    The authors have, in cooperation with industry, developed high-efficiency filters made from sintered stainless-steel fibers for use in several air-cleaning applications in the nuclear industry. These filters were developed to overcome the failure modes in present high-efficiently particulate air (HEPA) filters. HEPA filters are made from glass paper and glue, and they may fail when they get hot or wet and when they are overpressured. In developing steel filters, they first evaluated the commercially available stainless-steel filter media made from sintered powder and sintered fiber. The sintered-fiber media performed much better than sintered-powder media, and the best media had the smallest fiber diameter. Using the best media, prototype filters were then built for venting compressed gases and evaluated in their automated filter tester

  4. Development of high-efficiency solar cells on silicon web

    Science.gov (United States)

    Meier, D. L.; Greggi, J.; Okeeffe, T. W.; Rai-Choudhury, P.

    1986-01-01

    Work was performed to improve web base material with a goal of obtaining solar cell efficiencies in excess of 18% (AM1). Efforts in this program are directed toward identifying carrier loss mechanisms in web silicon, eliminating or reducing these mechanisms, designing a high efficiency cell structure with the aid of numerical models, and fabricating high efficiency web solar cells. Fabrication techniques must preserve or enhance carrier lifetime in the bulk of the cell and minimize recombination of carriers at the external surfaces. Three completed cells were viewed by cross-sectional transmission electron microscopy (TEM) in order to investigate further the relation between structural defects and electrical performance of web cells. Consistent with past TEM examinations, the cell with the highest efficiency (15.0%) had no dislocations but did have 11 twin planes.

  5. Potential high efficiency solar cells: Applications from space photovoltaic research

    Science.gov (United States)

    Flood, D. J.

    1986-01-01

    NASA involvement in photovoltaic energy conversion research development and applications spans over two decades of continuous progress. Solar cell research and development programs conducted by the Lewis Research Center's Photovoltaic Branch have produced a sound technology base not only for the space program, but for terrestrial applications as well. The fundamental goals which have guided the NASA photovoltaic program are to improve the efficiency and lifetime, and to reduce the mass and cost of photovoltaic energy conversion devices and arrays for use in space. The major efforts in the current Lewis program are on high efficiency, single crystal GaAs planar and concentrator cells, radiation hard InP cells, and superlattice solar cells. A brief historical perspective of accomplishments in high efficiency space solar cells will be given, and current work in all of the above categories will be described. The applicability of space cell research and technology to terrestrial photovoltaics will be discussed.

  6. Light-induced lattice expansion leads to high-efficiency perovskite solar cells

    Science.gov (United States)

    Tsai, Hsinhan; Asadpour, Reza; Blancon, Jean-Christophe; Stoumpos, Constantinos C.; Durand, Olivier; Strzalka, Joseph W.; Chen, Bo; Verduzco, Rafael; Ajayan, Pulickel M.; Tretiak, Sergei; Even, Jacky; Alam, Muhammad Ashraf; Kanatzidis, Mercouri G.; Nie, Wanyi; Mohite, Aditya D.

    2018-04-01

    Light-induced structural dynamics plays a vital role in the physical properties, device performance, and stability of hybrid perovskite–based optoelectronic devices. We report that continuous light illumination leads to a uniform lattice expansion in hybrid perovskite thin films, which is critical for obtaining high-efficiency photovoltaic devices. Correlated, in situ structural and device characterizations reveal that light-induced lattice expansion benefits the performances of a mixed-cation pure-halide planar device, boosting the power conversion efficiency from 18.5 to 20.5%. The lattice expansion leads to the relaxation of local lattice strain, which lowers the energetic barriers at the perovskite-contact interfaces, thus improving the open circuit voltage and fill factor. The light-induced lattice expansion did not compromise the stability of these high-efficiency photovoltaic devices under continuous operation at full-spectrum 1-sun (100 milliwatts per square centimeter) illumination for more than 1500 hours.

  7. Highly efficient single-layer dendrimer light-emitting diodes with balanced charge transport

    Science.gov (United States)

    Anthopoulos, Thomas D.; Markham, Jonathan P. J.; Namdas, Ebinazar B.; Samuel, Ifor D. W.; Lo, Shih-Chun; Burn, Paul L.

    2003-06-01

    High-efficiency single-layer-solution-processed green light-emitting diodes based on a phosphorescent dendrimer are demonstrated. A peak external quantum efficiency of 10.4% (35 cd/A) was measured for a first generation fac-tris(2-phenylpyridine) iridium cored dendrimer when blended with 4,4'-bis(N-carbazolyl)biphenyl and electron transporting 1,3,5-tris(2-N-phenylbenzimidazolyl)benzene at 8.1 V. A maximum power efficiency of 12.8 lm/W was measured also at 8.1 V and 550 cd/m2. These results indicate that, by simple blending of bipolar and electron-transporting molecules, highly efficient light-emitting diodes can be made employing a very simple device structure.

  8. Highly efficient red OLEDs using DCJTB as the dopant and delayed fluorescent exciplex as the host.

    Science.gov (United States)

    Zhao, Bo; Zhang, Tianyou; Chu, Bei; Li, Wenlian; Su, Zisheng; Wu, Hairuo; Yan, Xingwu; Jin, Fangming; Gao, Yuan; Liu, Chengyuan

    2015-05-29

    In this manuscript, we demonstrated a highly efficient DCJTB emission with delayed fluorescent exciplex TCTA:3P-T2T as the host. For the 1.0% DCJTB doped concentration, a maximum luminance, current efficiency, power efficiency and EQE of 22,767 cd m(-2), 22.7 cd A(-1), 21.5 lm W(-1) and 10.15% were achieved, respectively. The device performance is the best compared to either red OLEDs with traditional fluorescent emitter or traditional red phosphor of Ir(piq)3 doped into CBP host. The extraction of so high efficiency can be explained as the efficient triplet excitons up-conversion of TCTA:3P-T2T and the energy transfer from exciplex host singlet state to DCJTB singlet state.

  9. Highly efficient deep-blue organic light emitting diode with a carbazole based fluorescent emitter

    Science.gov (United States)

    Sahoo, Snehasis; Dubey, Deepak Kumar; Singh, Meenu; Joseph, Vellaichamy; Thomas, K. R. Justin; Jou, Jwo-Huei

    2018-04-01

    High efficiency deep-blue emission is essential to realize energy-saving, high-quality display and lighting applications. We demonstrate here a deep-blue organic light emitting diode using a novel carbazole based fluorescent emitter 7-[4-(diphenylamino)phenyl]-9-(2-ethylhexyl)-9H-carbazole-2-carbonitrile (JV234). The solution processed resultant device shows a maximum luminance above 1,750 cd m-2 and CIE coordinates (0.15,0.06) with a 1.3 lm W-1 power efficiency, 2.0 cd A-1 current efficiency, and 4.1% external quantum efficiency at 100 cd m-2. The resulting deep-blue emission enables a greater than 100% color saturation. The high efficiency may be attributed to the effective host-to-guest energy transfer, suitable device architecture facilitating balanced carrier injection and low doping concentration preventing efficiency roll-off caused by concentration quenching.

  10. Highly efficient electron vortex beams generated by nanofabricated phase holograms

    Energy Technology Data Exchange (ETDEWEB)

    Grillo, Vincenzo, E-mail: vincenzo.grillo@nano.cnr.it [CNR-Istituto Nanoscienze, Centro S3, Via G Campi 213/a, I-41125 Modena (Italy); CNR-IMEM Parco Area delle Scienze 37/A, I-43124 Parma (Italy); Carlo Gazzadi, Gian [CNR-Istituto Nanoscienze, Centro S3, Via G Campi 213/a, I-41125 Modena (Italy); Karimi, Ebrahim [CNR-Istituto Nanoscienze, Centro S3, Via G Campi 213/a, I-41125 Modena (Italy); Department of Physics, University of Ottawa, 150 Louis Pasteur, Ottawa, Ontario K1N 6N5 (Canada); Mafakheri, Erfan [Dipartimento di Fisica Informatica e Matematica, Università di Modena e Reggio Emilia, via G Campi 213/a, I-41125 Modena (Italy); Boyd, Robert W. [Department of Physics, University of Ottawa, 150 Louis Pasteur, Ottawa, Ontario K1N 6N5 (Canada); Frabboni, Stefano [CNR-Istituto Nanoscienze, Centro S3, Via G Campi 213/a, I-41125 Modena (Italy); Dipartimento di Fisica Informatica e Matematica, Università di Modena e Reggio Emilia, via G Campi 213/a, I-41125 Modena (Italy)

    2014-01-27

    We propose an improved type of holographic-plate suitable for the shaping of electron beams. The plate is fabricated by a focused ion beam on a silicon nitride membrane and introduces a controllable phase shift to the electron wavefunction. We adopted the optimal blazed-profile design for the phase hologram, which results in the generation of highly efficient (25%) electron vortex beams. This approach paves the route towards applications in nano-scale imaging and materials science.

  11. Holography as a highly efficient RG flow I: Rephrasing gravity

    OpenAIRE

    Behr, Nicolas; Kuperstein, Stanislav; Mukhopadhyay, Ayan

    2015-01-01

    We investigate how the holographic correspondence can be reformulated as a generalisation of Wilsonian RG flow in a strongly interacting large $N$ quantum field theory. We firstly define a \\textit{highly efficient RG flow} as one in which the Ward identities related to local conservation of energy, momentum and charges preserve the same form at each scale -- to achieve this it is necessary to redefine the background metric and external sources at each scale as functionals of the effective sin...

  12. Sm , Bi phosphors with high efficiency white-light-emittin

    Indian Academy of Sciences (India)

    2017-08-29

    Aug 29, 2017 ... Therefore, researches on high efficiency red phos- phors are very important. So far ..... ing concentration and reached a maximum at y = 8 mol%. A .... [10] Xue L P, Wang Y J, Lv P W, Chen D G, Lin Z, Liang J K et al. 2009 Crystal ... [28] Liu J, Xu B, Song C, Luo H, Zou X, Han L et al 2012 Cryst-. EngComm.

  13. High-Efficient Low-Cost Photovoltaics Recent Developments

    CERN Document Server

    Petrova-Koch, Vesselinka; Goetzberger, Adolf

    2009-01-01

    A bird's-eye view of the development and problems of recent photovoltaic cells and systems and prospects for Si feedstock is presented. High-efficient low-cost PV modules, making use of novel efficient solar cells (based on c-Si or III-V materials), and low cost solar concentrators are in the focus of this book. Recent developments of organic photovoltaics, which is expected to overcome its difficulties and to enter the market soon, are also included.

  14. Highly efficient procedure for the transesterification of vegetable oil

    Energy Technology Data Exchange (ETDEWEB)

    Liang, Xuezheng; Gao, Shan; He, Mingyuan [Shanghai Key Laboratory of Green Chemistry and Chemical Process, Department of Chemistry, East China Normal University, Shanghai 200062 (China); Yang, Jianguo [Shanghai Key Laboratory of Green Chemistry and Chemical Process, Department of Chemistry, East China Normal University, Shanghai 200062 (China); Energy Institute, Department of Materials Science and Engineering, Pennsylvania State University, University Park, PA 16802 (United States)

    2009-10-15

    The highly efficient procedure has been developed for the synthesis of biodiesel from vegetable oil and methanol. The KF/MgO has been selected as the most efficient catalyst for the reactions with the yield of 99.3%. Operational simplicity, without need of the purification of raw vegetable oil, low cost of the catalyst used, high activities, no saponification and reusability are the key features of this methodology. (author)

  15. Stabilization void-fill encapsulation high-efficiency particulate filters

    International Nuclear Information System (INIS)

    Alexander, R.G.; Stewart, W.E.; Phillips, S.J.; Serkowski, M.M.; England, J.L.; Boynton, H.C.

    1994-05-01

    This report discusses high-efficiency particulate air (HEPA) filter systems that which are contaminated with radionuclides are part of the nuclear fuel processing systems conducted by the US Department of Energy (DOE) and require replacement and safe and efficient disposal for plant safety. Two K-3 HEPA filters were removed from service, placed burial boxes, buried, and safely and efficiently stabilized remotely which reduced radiation exposure to personnel and the environment

  16. Global climate change: Mitigation opportunities high efficiency large chiller technology

    Energy Technology Data Exchange (ETDEWEB)

    Stanga, M.V.

    1997-12-31

    This paper, comprised of presentation viewgraphs, examines the impact of high efficiency large chiller technology on world electricity consumption and carbon dioxide emissions. Background data are summarized, and sample calculations are presented. Calculations show that presently available high energy efficiency chiller technology has the ability to substantially reduce energy consumption from large chillers. If this technology is widely implemented on a global basis, it could reduce carbon dioxide emissions by 65 million tons by 2010.

  17. Design of High Efficiency Illumination for LED Lighting

    OpenAIRE

    Chang, Yong-Nong; Cheng, Hung-Liang; Kuo, Chih-Ming

    2013-01-01

    A high efficiency illumination for LED street lighting is proposed. For energy saving, this paper uses Class-E resonant inverter as main electric circuit to improve efficiency. In addition, single dimming control has the best efficiency, simplest control scheme and lowest circuit cost among other types of dimming techniques. Multiple serial-connected transformers used to drive the LED strings as they can provide galvanic isolation and have the advantage of good current distribution against de...

  18. High-efficiency pumps drastically reduce energy consumption

    Energy Technology Data Exchange (ETDEWEB)

    Anon

    2002-05-01

    Wilo's Stratos pumps for air conditioning and other domestic heating applications combine the advantages of wet runner technology with an innovative electronic commutator motor. The energy consumption of these high-efficiency pumps is halved compared with similar wet runner designs. With vast numbers of pumps used in buildings across Europe alone, the adoption of this technology potentially offers significant energy sayings. (Author)

  19. The emerging High Efficiency Video Coding standard (HEVC)

    International Nuclear Information System (INIS)

    Raja, Gulistan; Khan, Awais

    2013-01-01

    High definition video (HDV) is becoming popular day by day. This paper describes the performance analysis of latest upcoming video standard known as High Efficiency Video Coding (HEVC). HEVC is designed to fulfil all the requirements for future high definition videos. In this paper, three configurations (intra only, low delay and random access) of HEVC are analyzed using various 480p, 720p and 1080p high definition test video sequences. Simulation results show the superior objective and subjective quality of HEVC

  20. Highly efficient electron vortex beams generated by nanofabricated phase holograms

    International Nuclear Information System (INIS)

    Grillo, Vincenzo; Carlo Gazzadi, Gian; Karimi, Ebrahim; Mafakheri, Erfan; Boyd, Robert W.; Frabboni, Stefano

    2014-01-01

    We propose an improved type of holographic-plate suitable for the shaping of electron beams. The plate is fabricated by a focused ion beam on a silicon nitride membrane and introduces a controllable phase shift to the electron wavefunction. We adopted the optimal blazed-profile design for the phase hologram, which results in the generation of highly efficient (25%) electron vortex beams. This approach paves the route towards applications in nano-scale imaging and materials science

  1. High-efficiency white OLEDs based on small molecules

    Science.gov (United States)

    Hatwar, Tukaram K.; Spindler, Jeffrey P.; Ricks, M. L.; Young, Ralph H.; Hamada, Yuuhiko; Saito, N.; Mameno, Kazunobu; Nishikawa, Ryuji; Takahashi, Hisakazu; Rajeswaran, G.

    2004-02-01

    Eastman Kodak Company and SANYO Electric Co., Ltd. recently demonstrated a 15" full-color, organic light-emitting diode display (OLED) using a high-efficiency white emitter combined with a color-filter array. Although useful for display applications, white emission from organic structures is also under consideration for other applications, such as solid-state lighting, where high efficiency and good color rendition are important. By incorporating adjacent blue and orange emitting layers in a multi-layer structure, highly efficient, stable white emission has been attained. With suitable host and dopant combinations, a luminance yield of 20 cd/A and efficiency of 8 lm/W have been achieved at a drive voltage of less than 8 volts and luminance level of 1000 cd/m2. The estimated external efficiency of this device is 6.3% and a high level of operational stability is observed. To our knowledge, this is the highest performance reported so far for white organic electroluminescent devices. We will review white OLED technology and discuss the fabrication and operating characteristics of these devices.

  2. High-Efficiency Nitride-Based Solid-State Lighting

    Energy Technology Data Exchange (ETDEWEB)

    Paul T. Fini; Shuji Nakamura

    2005-07-30

    In this final technical progress report we summarize research accomplished during Department of Energy contract DE-FC26-01NT41203, entitled ''High-Efficiency Nitride-Based Solid-State Lighting''. Two teams, from the University of California at Santa Barbara (Principle Investigator: Dr. Shuji Nakamura) and the Lighting Research Center at Rensselaer Polytechnic Institute (led by Dr. N. Narendran), pursued the goals of this contract from thin film growth, characterization, and packaging/luminaire design standpoints. The UCSB team initially pursued the development of blue gallium nitride (GaN)-based vertical-cavity surface-emitting lasers, as well as ultraviolet GaN-based light emitting diodes (LEDs). In Year 2, the emphasis shifted to resonant-cavity light emitting diodes, also known as micro-cavity LEDs when extremely thin device cavities are fabricated. These devices have very directional emission and higher light extraction efficiency than conventional LEDs. Via the optimization of thin-film growth and refinement of device processing, we decreased the total cavity thickness to less than 1 {micro}m, such that micro-cavity effects were clearly observed and a light extraction efficiency of over 10% was reached. We also began the development of photonic crystals for increased light extraction, in particular for so-called ''guided modes'' which would otherwise propagate laterally in the device and be re-absorbed. Finally, we pursued the growth of smooth, high-quality nonpolar a-plane and m-plane GaN films, as well as blue light emitting diodes on these novel films. Initial nonpolar LEDs showed the expected behavior of negligible peak wavelength shift with increasing drive current. M-plane LEDs in particular show promise, as unpackaged devices had unsaturated optical output power of {approx} 3 mW at 200 mA drive current. The LRC's tasks were aimed at developing the subcomponents necessary for packaging UCSB's light

  3. CFD application to advanced design for high efficiency spacer grid

    Energy Technology Data Exchange (ETDEWEB)

    Ikeda, Kazuo, E-mail: kazuo3_ikeda@ndc.mhi.co.jp

    2014-11-15

    Highlights: • A new LDV was developed to investigate the local velocity in a rod bundle and inside a spacer grid. • The design information that utilizes for high efficiency spacer grid has been obtained. • CFD methodology that predicts flow field in a PWR fuel has been developed. • The high efficiency spacer grid was designed using the CFD methodology. - Abstract: Pressurized water reactor (PWR) fuels have been developed to meet the needs of the market. A spacer grid is a key component to improve thermal hydraulic performance of a PWR fuel assembly. Mixing structures (vanes) of a spacer grid promote coolant mixing and enhance heat removal from fuel rods. A larger mixing vane would improve mixing effect, which would increase the departure from nucleate boiling (DNB) benefit for fuel. However, the increased pressure loss at large mixing vanes would reduce the coolant flow at the mixed fuel core, which would reduce the DNB margin. The solution is to develop a spacer grid whose pressure loss is equal to or less than the current spacer grid and that has higher critical heat flux (CHF) performance. For this reason, a requirement of design tool for predicting the pressure loss and CHF performance of spacer grids has been increased. The author and co-workers have been worked for development of high efficiency spacer grid using Computational Fluid Dynamics (CFD) for nearly 20 years. A new laser Doppler velocimetry (LDV), which is miniaturized with fiber optics embedded in a fuel cladding, was developed to investigate the local velocity profile in a rod bundle and inside a spacer grid. The rod-embedded fiber LDV (rod LDV) can be inserted in an arbitrary grid cell instead of a fuel rod, and has the advantage of not disturbing the flow field since it is the same shape as a fuel rod. The probe volume of the rod LDV is small enough to measure spatial velocity profile in a rod gap and inside a spacer grid. According to benchmark experiments such as flow velocity

  4. CFD application to advanced design for high efficiency spacer grid

    International Nuclear Information System (INIS)

    Ikeda, Kazuo

    2014-01-01

    Highlights: • A new LDV was developed to investigate the local velocity in a rod bundle and inside a spacer grid. • The design information that utilizes for high efficiency spacer grid has been obtained. • CFD methodology that predicts flow field in a PWR fuel has been developed. • The high efficiency spacer grid was designed using the CFD methodology. - Abstract: Pressurized water reactor (PWR) fuels have been developed to meet the needs of the market. A spacer grid is a key component to improve thermal hydraulic performance of a PWR fuel assembly. Mixing structures (vanes) of a spacer grid promote coolant mixing and enhance heat removal from fuel rods. A larger mixing vane would improve mixing effect, which would increase the departure from nucleate boiling (DNB) benefit for fuel. However, the increased pressure loss at large mixing vanes would reduce the coolant flow at the mixed fuel core, which would reduce the DNB margin. The solution is to develop a spacer grid whose pressure loss is equal to or less than the current spacer grid and that has higher critical heat flux (CHF) performance. For this reason, a requirement of design tool for predicting the pressure loss and CHF performance of spacer grids has been increased. The author and co-workers have been worked for development of high efficiency spacer grid using Computational Fluid Dynamics (CFD) for nearly 20 years. A new laser Doppler velocimetry (LDV), which is miniaturized with fiber optics embedded in a fuel cladding, was developed to investigate the local velocity profile in a rod bundle and inside a spacer grid. The rod-embedded fiber LDV (rod LDV) can be inserted in an arbitrary grid cell instead of a fuel rod, and has the advantage of not disturbing the flow field since it is the same shape as a fuel rod. The probe volume of the rod LDV is small enough to measure spatial velocity profile in a rod gap and inside a spacer grid. According to benchmark experiments such as flow velocity

  5. Design of a high efficiency 30 kW boost composite converter

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyeokjin [Univ. of Colorado, Boulder, CO (United States); Chen, Hua [Univ. of Colorado, Boulder, CO (United States); Maksimovic, Dragan [Univ. of Colorado, Boulder, CO (United States); Erickson, Robert W. [Univ. of Colorado, Boulder, CO (United States)

    2015-09-20

    An experimental 30 kW boost composite converter is described in this paper. The composite converter architecture, which consists of a buck module, a boost module, and a dual active bridge module that operates as a DC transformer (DCX), leads to substantial reductions in losses at partial power points, and to significant improvements in weighted efficiency in applications that require wide variations in power and conversion ratio. A comprehensive loss model is developed, accounting for semiconductor conduction and switching losses, capacitor losses, as well as dc and ac losses in magnetic components. Based on the developed loss model, the module and system designs are optimized to maximize efficiency at a 50% power point. Experimental results for the 30 kW prototype demonstrate 98.5%peak efficiency, very high efficiency over wide ranges of power and voltage conversion ratios, as well as excellent agreements between model predictions and measured efficiency curves.

  6. The Design of High Efficiency Crossflow Hydro Turbines: A Review and Extension

    Directory of Open Access Journals (Sweden)

    Ram Adhikari

    2018-01-01

    Full Text Available Efficiency is a critical consideration in the design of hydro turbines. The crossflow turbine is the cheapest and easiest hydro turbine to manufacture and so is commonly used in remote power systems for developing countries. A longstanding problem for practical crossflow turbines is their lower maximum efficiency compared to their more advanced counterparts, such as Pelton and Francis turbines. This paper reviews the experimental and computational studies relevant to the design of high efficiency crossflow turbines. We concentrate on the studies that have contributed to designs with efficiencies in the range of 88–90%. Many recent studies have been conducted on turbines of low maximum efficiency, which we believe is due to misunderstanding of design principles for achieving high efficiencies. We synthesize the key results of experimental and computational fluid dynamics studies to highlight the key fundamental design principles for achieving efficiencies of about 90%, as well as future research and development areas to further improve the maximum efficiency. The main finding of this review is that the total conversion of head into kinetic energy in the nozzle and the matching of nozzle and runner designs are the two main design requirements for the design of high efficiency turbines.

  7. Heat pumps; Synergy of high efficiency and low carbon electricity

    Energy Technology Data Exchange (ETDEWEB)

    Koike, Akio

    2010-09-15

    Heat pump is attracting wide attention for its high efficiency to utilize inexhaustible and renewable ambient heat in the environment. With its rapid innovation and efficiency improvement, this technology has a huge potential to reduce CO2 emissions by replacing currently widespread fossil fuel combustion systems to meet various heat demands from the residential, commercial and industrial sectors. Barriers to deployment such as low public awareness and a relatively long pay-back period do exist, so it is strongly recommended that each country implement policies to promote heat pumps as a renewable energy option and an effective method to combat global warming.

  8. Development of large area, high efficiency amorphous silicon solar cell

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, K.S.; Kim, S.; Kim, D.W. [Yu Kong Taedok Institute of Technology (Korea, Republic of)

    1996-02-01

    The objective of the research is to develop the mass-production technologies of high efficiency amorphous silicon solar cells in order to reduce the costs of solar cells and dissemination of solar cells. Amorphous silicon solar cell is the most promising option of thin film solar cells which are relatively easy to reduce the costs. The final goal of the research is to develop amorphous silicon solar cells having the efficiency of 10%, the ratio of light-induced degradation 15% in the area of 1200 cm{sup 2} and test the cells in the form of 2 Kw grid-connected photovoltaic system. (author) 35 refs., 8 tabs., 67 figs.

  9. High-efficiency ventilated metamaterial absorber at low frequency

    Science.gov (United States)

    Wu, Xiaoxiao; Au-Yeung, Ka Yan; Li, Xin; Roberts, Robert Christopher; Tian, Jingxuan; Hu, Chuandeng; Huang, Yingzhou; Wang, Shuxia; Yang, Zhiyu; Wen, Weijia

    2018-03-01

    We demonstrate a ventilated metamaterial absorber operating at low frequency (90%) has been achieved in both simulations and experiments. This high-efficiency absorption under the ventilation condition originates from the weak coupling of two identical split tube resonators constituting the absorber, which leads to the hybridization of the degenerate eigenmodes and breaks the absorption upper limit of 50% for conventional transmissive symmetric acoustic absorbers. The absorber can also be extended to an array and work in free space. The absorber should have potential applications in acoustic engineering where both noise reduction and ventilation are required.

  10. Polarization holograms allow highly efficient generation of complex light beams.

    Science.gov (United States)

    Ruiz, U; Pagliusi, P; Provenzano, C; Volke-Sepúlveda, K; Cipparrone, Gabriella

    2013-03-25

    We report a viable method to generate complex beams, such as the non-diffracting Bessel and Weber beams, which relies on the encoding of amplitude information, in addition to phase and polarization, using polarization holography. The holograms are recorded in polarization sensitive films by the interference of a reference plane wave with a tailored complex beam, having orthogonal circular polarizations. The high efficiency, the intrinsic achromaticity and the simplicity of use of the polarization holograms make them competitive with respect to existing methods and attractive for several applications. Theoretical analysis, based on the Jones formalism, and experimental results are shown.

  11. High bandgap III-V alloys for high efficiency optoelectronics

    Energy Technology Data Exchange (ETDEWEB)

    Alberi, Kirstin; Mascarenhas, Angelo; Wanlass, Mark

    2017-01-10

    High bandgap alloys for high efficiency optoelectronics are disclosed. An exemplary optoelectronic device may include a substrate, at least one Al.sub.1-xIn.sub.xP layer, and a step-grade buffer between the substrate and at least one Al.sub.1-xIn.sub.xP layer. The buffer may begin with a layer that is substantially lattice matched to GaAs, and may then incrementally increase the lattice constant in each sequential layer until a predetermined lattice constant of Al.sub.1-xIn.sub.xP is reached.

  12. Iodine laser of high efficiency and fast repetition rate

    Energy Technology Data Exchange (ETDEWEB)

    Hohla, K; Witte, K J

    1976-07-01

    The scaling laws of an iodine laser of high efficiency and fast repetition rate are reported. The laser is pumped with a new kind of low pressure Hg-UV-lamps which convert 32% of the electrical input in UV-light in the absorption band of the iodine laser and which can be fired up to 100 Hz. Details of a 10 kJ/1 nsec system as dimensions, energy density, repetition rate, flow velocity, gas composition and gas pressure and the overall efficiency are given which is expected to be about 2%.

  13. The problems of high efficient extraction from the isochronous cyclotron

    International Nuclear Information System (INIS)

    Schwabe, J.

    1994-06-01

    The problem of high efficient extraction (η ≥ 50%) from isochronous cyclotrons (with the exception of the stripping method) is not completely solved up to this day. This problem is specifically important, because these cyclotrons are being also applied in the production of medical radioisotopes, labeled pharmaceuticals as well as in neutron therapy (oncology), machine industry, agriculture (plant mutagenesis), etc. The aim of the proposed topic is to solve this problem on the AIC-144 isochronous cyclotron in the INP (Institute of Nuclear Physics). Lately, a beam of 20 MeV deuterons with an efficiency of ca. 15% was extracted from this cyclotron. (author). 25 refs, 14 figs

  14. Design of High Efficiency Illumination for LED Lighting

    Directory of Open Access Journals (Sweden)

    Yong-Nong Chang

    2013-01-01

    Full Text Available A high efficiency illumination for LED street lighting is proposed. For energy saving, this paper uses Class-E resonant inverter as main electric circuit to improve efficiency. In addition, single dimming control has the best efficiency, simplest control scheme and lowest circuit cost among other types of dimming techniques. Multiple serial-connected transformers used to drive the LED strings as they can provide galvanic isolation and have the advantage of good current distribution against device difference. Finally, a prototype circuit for driving 112 W LEDs in total was built and tested to verify the theoretical analysis.

  15. Research on High Efficient Single-Phase Multi-Stage Interleaved Bridgeless PFC Frontend for Class-D Amplifiers

    DEFF Research Database (Denmark)

    Li, Qingnan; Thomsen, Ole Cornelius; Andersen, Michael A. E.

    2012-01-01

    In this paper, a 3.5kW single-phase high efficient interleaved Bridgeless PFC (IBPFC) is proposed for class-D amplifiers. This topology achieves a relatively higher efficiency in a wide output power range, which helps to reduce the energy consuming of the whole system. In addition, a detailed...

  16. High efficiency video coding coding tools and specification

    CERN Document Server

    Wien, Mathias

    2015-01-01

    The video coding standard High Efficiency Video Coding (HEVC) targets at improved compression performance for video resolutions of HD and beyond, providing Ultra HD video at similar compressed bit rates as for HD video encoded with the well-established video coding standard H.264 | AVC. Based on known concepts, new coding structures and improved coding tools have been developed and specified in HEVC. The standard is expected to be taken up easily by established industry as well as new endeavors, answering the needs of todays connected and ever-evolving online world. This book presents the High Efficiency Video Coding standard and explains it in a clear and coherent language. It provides a comprehensive and consistently written description, all of a piece. The book targets at both, newbies to video coding as well as experts in the field. While providing sections with introductory text for the beginner, it suits as a well-arranged reference book for the expert. The book provides a comprehensive reference for th...

  17. Detecting Android Malwares with High-Efficient Hybrid Analyzing Methods

    Directory of Open Access Journals (Sweden)

    Yu Liu

    2018-01-01

    Full Text Available In order to tackle the security issues caused by malwares of Android OS, we proposed a high-efficient hybrid-detecting scheme for Android malwares. Our scheme employed different analyzing methods (static and dynamic methods to construct a flexible detecting scheme. In this paper, we proposed some detecting techniques such as Com+ feature based on traditional Permission and API call features to improve the performance of static detection. The collapsing issue of traditional function call graph-based malware detection was also avoided, as we adopted feature selection and clustering method to unify function call graph features of various dimensions into same dimension. In order to verify the performance of our scheme, we built an open-access malware dataset in our experiments. The experimental results showed that the suggested scheme achieved high malware-detecting accuracy, and the scheme could be used to establish Android malware-detecting cloud services, which can automatically adopt high-efficiency analyzing methods according to the properties of the Android applications.

  18. A highly efficient graphene oxide absorber for Q-switched Nd:GdVO4 lasers

    International Nuclear Information System (INIS)

    Wang Yonggang; Wen Xiaoming; Tang Jau; Chen, Hou Ren; Hsieh, Wen Feng

    2011-01-01

    We demonstrated that graphene oxide material could be used as a highly efficient saturable absorber for the Q-switched Nd:GdVO 4 laser. A novel and low-cost graphene oxide (GO) absorber was fabricated by a vertical evaporation technique and high viscosity of polyvinyl alcohol (PVA) aqueous solution. A piece of GO/PVA absorber, a piece of round quartz, and an output coupler mirror were combined to be a sandwich structure passive component. Using such a structure, 104 ns pulses and 1.22 W average output power were obtained with the maximum pulse energy at 2 µJ and a slope efficiency of 17%.

  19. Game-Theoretic Rate-Distortion-Complexity Optimization of High Efficiency Video Coding

    DEFF Research Database (Denmark)

    Ukhanova, Ann; Milani, Simone; Forchhammer, Søren

    2013-01-01

    profiles in order to tailor the computational load to the different hardware and power-supply resources of devices. In this work, we focus on optimizing the quantization parameter and partition depth in HEVC via a game-theoretic approach. The proposed rate control strategy alone provides 0.2 dB improvement......This paper presents an algorithm for rate-distortioncomplexity optimization for the emerging High Efficiency Video Coding (HEVC) standard, whose high computational requirements urge the need for low-complexity optimization algorithms. Optimization approaches need to specify different complexity...

  20. Highly Efficient PCDTBT:PC71 BM Based Photovoltaic Devices without Thermal Annealing Treatment

    International Nuclear Information System (INIS)

    Yang Shao-Peng; Kong Wei-Guang; Liu Bo-Ya; Fu Guang-Sheng; Zheng Wen-Yao; Li Bao-Min; Liu Xian-Hao

    2011-01-01

    We propose an effective method to fabricate highly efficient organic photovoltaic cells based on poly [N-9 - heptadecanyl-2, 7-carbazole-alt-5,5-(4'7'-di-2-thienyl-2'1'3-b-enzothiadiazole): [6,6]-phenyl C 71 -butyric acid methyl ester (PCDTBT:PC 71 BM). A power conversion efficiency of as high as 5.6% and a fill factor of 53.7% are achieved from the optimized cells. The influence of surface morphology of the active layer on the performance of the cells is also investigated. (cross-disciplinary physics and related areas of science and technology)

  1. 2 W high efficiency PbS mid-infrared surface emitting laser

    Science.gov (United States)

    Ishida, A.; Sugiyama, Y.; Isaji, Y.; Kodama, K.; Takano, Y.; Sakata, H.; Rahim, M.; Khiar, A.; Fill, M.; Felder, F.; Zogg, H.

    2011-09-01

    High efficiency laser operation with output power exceeding 2 W was obtained for vertical external-cavity PbS based IV-VI compound surface emitting quantum-well structures. The laser showed external quantum efficiency as high as 16%. Generally, mid-infrared III-V or II-VI semiconductor laser operation utilizing interband electron transitions are restricted by Auger recombination and free carrier absorption. Auger recombination is much lower in the IV-VI semiconductors, and the free-carrier absorption is significantly reduced by an optically pumped laser structure including multi-step optical excitation layers.

  2. A High-Efficiency Wind Energy Harvester for Autonomous Embedded Systems.

    Science.gov (United States)

    Brunelli, Davide

    2016-03-04

    Energy harvesting is currently a hot research topic, mainly as a consequence of the increasing attractiveness of computing and sensing solutions based on small, low-power distributed embedded systems. Harvesting may enable systems to operate in a deploy-and-forget mode, particularly when power grid is absent and the use of rechargeable batteries is unattractive due to their limited lifetime and maintenance requirements. This paper focuses on wind flow as an energy source feasible to meet the energy needs of a small autonomous embedded system. In particular the contribution is on the electrical converter and system integration. We characterize the micro-wind turbine, we define a detailed model of its behaviour, and then we focused on a highly efficient circuit to convert wind energy into electrical energy. The optimized design features an overall volume smaller than 64 cm³. The core of the harvester is a high efficiency buck-boost converter which performs an optimal power point tracking. Experimental results show that the wind generator boosts efficiency over a wide range of operating conditions.

  3. A High-Efficiency Wind Energy Harvester for Autonomous Embedded Systems

    Science.gov (United States)

    Brunelli, Davide

    2016-01-01

    Energy harvesting is currently a hot research topic, mainly as a consequence of the increasing attractiveness of computing and sensing solutions based on small, low-power distributed embedded systems. Harvesting may enable systems to operate in a deploy-and-forget mode, particularly when power grid is absent and the use of rechargeable batteries is unattractive due to their limited lifetime and maintenance requirements. This paper focuses on wind flow as an energy source feasible to meet the energy needs of a small autonomous embedded system. In particular the contribution is on the electrical converter and system integration. We characterize the micro-wind turbine, we define a detailed model of its behaviour, and then we focused on a highly efficient circuit to convert wind energy into electrical energy. The optimized design features an overall volume smaller than 64 cm3. The core of the harvester is a high efficiency buck-boost converter which performs an optimal power point tracking. Experimental results show that the wind generator boosts efficiency over a wide range of operating conditions. PMID:26959018

  4. A High-Efficiency Wind Energy Harvester for Autonomous Embedded Systems

    Directory of Open Access Journals (Sweden)

    Davide Brunelli

    2016-03-01

    Full Text Available Energy harvesting is currently a hot research topic, mainly as a consequence of the increasing attractiveness of computing and sensing solutions based on small, low-power distributed embedded systems. Harvesting may enable systems to operate in a deploy-and-forget mode, particularly when power grid is absent and the use of rechargeable batteries is unattractive due to their limited lifetime and maintenance requirements. This paper focuses on wind flow as an energy source feasible to meet the energy needs of a small autonomous embedded system. In particular the contribution is on the electrical converter and system integration. We characterize the micro-wind turbine, we define a detailed model of its behaviour, and then we focused on a highly efficient circuit to convert wind energy into electrical energy. The optimized design features an overall volume smaller than 64 cm3. The core of the harvester is a high efficiency buck-boost converter which performs an optimal power point tracking. Experimental results show that the wind generator boosts efficiency over a wide range of operating conditions.

  5. Highly efficient 400  W near-fundamental-mode green thin-disk laser.

    Science.gov (United States)

    Piehler, Stefan; Dietrich, Tom; Rumpel, Martin; Graf, Thomas; Ahmed, Marwan Abdou

    2016-01-01

    We report on the efficient generation of continuous-wave, high-brightness green laser radiation. Green lasers are particularly interesting for reliable and reproducible deep-penetration welding of copper or for pumping Ti:Sa oscillators. By intracavity second-harmonic generation in a thin-disk laser resonator designed for fundamental-mode operation, an output power of up to 403 W is demonstrated at a wavelength of 515 nm with almost diffraction-limited beam quality. The unprecedented optical efficiency of 40.7% of green output power with respect to the pump power of the thin-disk laser is enabled by the intracavity use of a highly efficient grating waveguide mirror, which combines the functions of wavelength stabilization and spectral narrowing, as well as polarization selection in a single element.

  6. The High-efficiency LED Driver for Visible Light Communication Applications.

    Science.gov (United States)

    Gong, Cihun-Siyong Alex; Lee, Yu-Chen; Lai, Jyun-Liang; Yu, Chueh-Hao; Huang, Li Ren; Yang, Chia-Yen

    2016-08-08

    This paper presents a LED driver for VLC. The main purpose is to solve the low data rate problem used to be in switching type LED driver. The GaN power device is proposed to replace the traditional silicon power device of switching LED driver for the purpose of increasing switching frequency of converter, thereby increasing the bandwidth of data transmission. To achieve high efficiency, the diode-connected GaN power transistor is utilized to replace the traditional ultrafast recovery diode used to be in switching type LED driver. This work has been experimentally evaluated on 350-mA output current. The results demonstrate that it supports the data of PWM dimming level encoded in the PPM scheme for VLC application. The experimental results also show that system's efficiency of 80.8% can be achieved at 1-Mb/s data rate.

  7. High efficiency 40 K single-stage Stirling-type pulse tube cryocooler

    Science.gov (United States)

    Wu, X. L.; Chen, L. B.; Pan, C. Z.; Cui, C.; Wang, J. J.; Zhou, Y.

    2017-12-01

    A high efficiency single-stage Stirling-type coaxial pulse tube cryocooler (SPTC) operating at around 40 K has been designed, built and tested. The double-inlet and the inertance tubes together with the gas reservoir were adopted as the phase shifters. Under the conditions of 2.5 MPa charging pressure and 30 Hz operating frequency, the prototype has achieved a no-load temperature of 23.8 K with 330 W of electric input power at a rejection temperature of 279 K. When the input power increases to 400 W, it can achieve a cooling capacity of 4.7 W/40 K while rejecting heat at 279 K yielding an efficiency of 7.02% relative to Carnot. It achieves a cooling capacity of 5 W/40 K with an input power of 450 W. It takes 10 minutes for the SPTC to cool to its no-load temperature of 40 K from 295 K.

  8. X-parameter Based GaN Device Modeling and its Application to a High-efficiency PA Design

    DEFF Research Database (Denmark)

    Wang, Yelin; Nielsen, Troels Studsgaard; Jensen, Ole Kiel

    2014-01-01

    X-parameters are supersets of S-parameters and applicable to both linear and nonlinear system modeling. In this paper, a packaged 6 W Gallium Nitride (GaN) RF power transistor is modeled using load-dependent X-parameters by simulations. During the device characterization the load impedance is tuned...... to decrease the complexity of a harmonic load-pull measurement setup. A high-efficiency 2 GHz power amplifier is also designed for further validation of the concept....

  9. Microbial electrolytic disinfection process for highly efficient Escherichia coli inactivation

    DEFF Research Database (Denmark)

    Zhou, Shaofeng; Huang, Shaobin; Li, Xiaohu

    2018-01-01

    extensively studied for recalcitrant organics removal, its application potential towards water disinfection (e.g., inactivation of pathogens) is still unknown. This study investigated the inactivation of Escherichia coli in a microbial electrolysis cell based bio-electro-Fenton system (renamed as microbial......Water quality deterioration caused by a wide variety of recalcitrant organics and pathogenic microorganisms has become a serious concern worldwide. Bio-electro-Fenton systems have been considered as cost-effective and highly efficient water treatment platform technology. While it has been......]OH was identified as one potential mechanism for disinfection. This study successfully demonstrated the feasibility of bio-electro-Fenton process for pathogens inactivation, which offers insight for the future development of sustainable, efficient, and cost-effective biological water treatment technology....

  10. Highly efficient light management for perovskite solar cells.

    Science.gov (United States)

    Wang, Dong-Lin; Cui, Hui-Juan; Hou, Guo-Jiao; Zhu, Zhen-Gang; Yan, Qing-Bo; Su, Gang

    2016-01-06

    Organic-inorganic halide perovskite solar cells have enormous potential to impact the existing photovoltaic industry. As realizing a higher conversion efficiency of the solar cell is still the most crucial task, a great number of schemes were proposed to minimize the carrier loss by optimizing the electrical properties of the perovskite solar cells. Here, we focus on another significant aspect that is to minimize the light loss by optimizing the light management to gain a high efficiency for perovskite solar cells. In our scheme, the slotted and inverted prism structured SiO2 layers are adopted to trap more light into the solar cells, and a better transparent conducting oxide layer is employed to reduce the parasitic absorption. For such an implementation, the efficiency and the serviceable angle of the perovskite solar cell can be promoted impressively. This proposal would shed new light on developing the high-performance perovskite solar cells.

  11. Improved entropy encoding for high efficient video coding standard

    Directory of Open Access Journals (Sweden)

    B.S. Sunil Kumar

    2018-03-01

    Full Text Available The High Efficiency Video Coding (HEVC has better coding efficiency, but the encoding performance has to be improved to meet the growing multimedia applications. This paper improves the standard entropy encoding by introducing the optimized weighing parameters, so that higher rate of compression can be accomplished over the standard entropy encoding. The optimization is performed using the recently introduced firefly algorithm. The experimentation is carried out using eight benchmark video sequences and the PSNR for varying rate of data transmission is investigated. Comparative analysis based on the performance statistics is made with the standard entropy encoding. From the obtained results, it is clear that the originality of the decoded video sequence is preserved far better than the proposed method, though the compression rate is increased. Keywords: Entropy, Encoding, HEVC, PSNR, Compression

  12. Simple processing of high efficiency silicon solar cells

    International Nuclear Information System (INIS)

    Hamammu, I.M.; Ibrahim, K.

    2006-01-01

    Cost effective photovoltaic devices have been an area research since the development of the first solar cells, as cost is the major factor in their usage. Silicon solar cells have the biggest share in the photovoltaic market, though silicon os not the optimal material for solar cells. This work introduces a simplified approach for high efficiency silicon solar cell processing, by minimizing the processing steps and thereby reducing cost. The suggested procedure might also allow for the usage of lower quality materials compared to the one used today. The main features of the present work fall into: simplifying the diffusion process, edge shunt isolation and using acidic texturing instead of the standard alkaline processing. Solar cells of 17% efficiency have been produced using this procedure. Investigations on the possibility of improving the efficiency and using less quality material are still underway

  13. Highly Efficient Coherent Optical Memory Based on Electromagnetically Induced Transparency

    Science.gov (United States)

    Hsiao, Ya-Fen; Tsai, Pin-Ju; Chen, Hung-Shiue; Lin, Sheng-Xiang; Hung, Chih-Chiao; Lee, Chih-Hsi; Chen, Yi-Hsin; Chen, Yong-Fan; Yu, Ite A.; Chen, Ying-Cheng

    2018-05-01

    Quantum memory is an important component in the long-distance quantum communication based on the quantum repeater protocol. To outperform the direct transmission of photons with quantum repeaters, it is crucial to develop quantum memories with high fidelity, high efficiency and a long storage time. Here, we achieve a storage efficiency of 92.0 (1.5)% for a coherent optical memory based on the electromagnetically induced transparency scheme in optically dense cold atomic media. We also obtain a useful time-bandwidth product of 1200, considering only storage where the retrieval efficiency remains above 50%. Both are the best record to date in all kinds of schemes for the realization of optical memory. Our work significantly advances the pursuit of a high-performance optical memory and should have important applications in quantum information science.

  14. High-Temperature High-Efficiency Solar Thermoelectric Generators

    Energy Technology Data Exchange (ETDEWEB)

    Baranowski, LL; Warren, EL; Toberer, ES

    2014-03-01

    Inspired by recent high-efficiency thermoelectric modules, we consider thermoelectrics for terrestrial applications in concentrated solar thermoelectric generators (STEGs). The STEG is modeled as two subsystems: a TEG, and a solar absorber that efficiently captures the concentrated sunlight and limits radiative losses from the system. The TEG subsystem is modeled using thermoelectric compatibility theory; this model does not constrain the material properties to be constant with temperature. Considering a three-stage TEG based on current record modules, this model suggests that 18% efficiency could be experimentally expected with a temperature gradient of 1000A degrees C to 100A degrees C. Achieving 15% overall STEG efficiency thus requires an absorber efficiency above 85%, and we consider two methods to achieve this: solar-selective absorbers and thermally insulating cavities. When the TEG and absorber subsystem models are combined, we expect that the STEG modeled here could achieve 15% efficiency with optical concentration between 250 and 300 suns.

  15. A Low VSWR and High Efficiency Waveguide Feed Antenna Array

    Directory of Open Access Journals (Sweden)

    Zhao Xiao-Fang

    2018-01-01

    Full Text Available A low VSWR and high efficiency antenna array operating in the Ku band for satellite communications is presented in this paper. To achieve high radiation efficiency and broad enough bandwidth, all-metal radiation elements and full-corporate waveguide feeding network are employed. As the general milling method is used in the multilayer antenna array fabrication, the E-plane waveguide feeding network is adopted here to suppress the wave leakage caused by the imperfect connectivity between adjacent layers. A 4 × 8 elements array prototype was fabricated and tested for verification. The measured results of proposed antenna array show bandwidth of 6.9% (13.9–14.8 GHz for VSWR < 1.5. Furthermore, antenna gain and efficiency of higher than 22.2 dBi and 80% are also exhibited, respectively.

  16. Disposal of aqueous condensate from high efficiency gas boilers

    Energy Technology Data Exchange (ETDEWEB)

    Hardwick, G J; Pattison, J R

    1984-01-01

    If highly efficient gas-fired condensing heating appliances are installed in Britain, the aqueous condensate produced can be conveniently run into existing sewage drains. The part of the drainage system that is most vulnerable to corrosion from the mildly acid condensate is that portion adjacent to the domestic premises. The tests described indicate that this is not at risk and the only precaution that might be considered necessary is to avoid running the condensate over galvanized drain covers in order to prevent unsightly staining. Water authorities in Britain and detailed studies in the US and Holland confirm that the condensate - after dilution by domestic waste, sewage, and rainwater - would be harmless to municipal sewage systems and would not, either in volume or chemical composition, affect the working of existing sewage treatment plants.

  17. High efficiency particulate removal with sintered metal filters

    International Nuclear Information System (INIS)

    Kirstein, B.E.; Paplawsky, W.J.; Pence, D.T.; Hedahl, T.G.

    1981-01-01

    Because of their particle removal efficiencies and durability, sintered metal filters have been chosen for high efficiency particulate air (HEPA) filter protection in the off-gas treatment system for the proposed Idaho National Engineering Laboratory Transuranic Waste Treatment Facility. Process evaluation of sintered metal filters indicated a lack of sufficient process design data to ensure trouble-free operation. Subsequence pilot scale testing was performed with flyash as the test particulate. The test results showed that the sintered metal filters can have an efficiency greater than 0.9999999 for the specific test conditions used. Stable pressure drop characteristics were observed in pulsed and reversed flow blowback modes of operation. Over 4900 hours of operation were obtained with operating conditions ranging up to approximately 90 0 C and 24 vol % water vapor in the gas stream

  18. Highly Efficient Catalytic Cyclic Carbonate Formation by Pyridyl Salicylimines.

    Science.gov (United States)

    Subramanian, Saravanan; Park, Joonho; Byun, Jeehye; Jung, Yousung; Yavuz, Cafer T

    2018-03-21

    Cyclic carbonates as industrial commodities offer a viable nonredox carbon dioxide fixation, and suitable heterogeneous catalysts are vital for their widespread implementation. Here, we report a highly efficient heterogeneous catalyst for CO 2 addition to epoxides based on a newly identified active catalytic pocket consisting of pyridine, imine, and phenol moieties. The polymeric, metal-free catalyst derived from this active site converts less-reactive styrene oxide under atmospheric pressure in quantitative yield and selectivity to the corresponding carbonate. The catalyst does not need additives, solvents, metals, or co-catalysts, can be reused at least 10 cycles without the loss of activity, and scaled up easily to a kilogram scale. Density functional theory calculations reveal that the nucleophilicity of pyridine base gets stronger due to the conjugated imines and H-bonding from phenol accelerates the reaction forward by stabilizing the intermediate.

  19. Development and evaluation of a cleanable high efficiency steel filter

    International Nuclear Information System (INIS)

    Bergman, W.; Larsen, G.; Weber, F.; Wilson, P.; Lopez, R.; Valha, G.; Conner, J.; Garr, J.; Williams, K.; Biermann, A.; Wilson, K.; Moore, P.; Gellner, C.; Rapchun, D.; Simon, K.; Turley, J.; Frye, L.; Monroe, D.

    1993-01-01

    We have developed a high efficiency steel filter that can be cleaned in-situ by reverse air pulses. The filter consists of 64 pleated cylindrical filter elements packaged into a 6l0 x 6l0 x 292 mm aluminum frame and has 13.5 m 2 of filter area. The filter media consists of a sintered steel fiber mat using 2 μm diameter fibers. We conducted an optimization study for filter efficiency and pressure drop to determine the filter design parameters of pleat width, pleat depth, outside diameter of the cylinder, and the total number of cylinders. Several prototype cylinders were then built and evaluated in terms of filter cleaning by reverse air pulses. The results of these studies were used to build the high efficiency steel filter. We evaluated the prototype filter for efficiency and cleanability. The DOP filter certification test showed the filter has a passing efficiency of 99.99% but a failing pressure drop of 0.80 kPa at 1,700 m 3 /hr. Since we were not able to achieve a pressure drop less than 0.25 kPa, the steel filter does not meet all the criteria for a HEPA filter. Filter loading and cleaning tests using AC Fine dust showed the filter could be repeatedly cleaned by reverse air pulses. The next phase of the prototype evaluation consisted of installing the unit and support housing in the exhaust duct work of a uranium grit blaster for a field evaluation at the Y-12 Plant in Oak Ridge, TN. The grit blaster is used to clean the surface of uranium parts and generates a cloud of UO 2 aerosols. We used a 1,700 m 3 /hr slip stream from the 10,200 m 3 /hr exhaust system

  20. Comparison of high efficiency particulate filter testing methods

    International Nuclear Information System (INIS)

    1985-01-01

    High Efficiency Particulate Air (HEPA) filters are used for the removal of submicron size particulates from air streams. In nuclear industry they are used as an important engineering safeguard to prevent the release of air borne radioactive particulates to the environment. HEPA filters used in the nuclear industry should therefore be manufactured and operated under strict quality control. There are three levels of testing HEPA filters: i) testing of the filter media; ii) testing of the assembled filter including filter media and filter housing; and iii) on site testing of the complete filter installation before putting into operation and later for the purpose of periodic control. A co-ordinated research programme on particulate filter testing methods was taken up by the Agency and contracts were awarded to the Member Countries, Belgium, German Democratic Republic, India and Hungary. The investigations carried out by the participants of the present co-ordinated research programme include the results of the nowadays most frequently used HEPA filter testing methods both for filter medium test, rig test and in-situ test purposes. Most of the experiments were carried out at ambient temperature and humidity, but indications were given to extend the investigations to elevated temperature and humidity in the future for the purpose of testing the performance of HEPA filter under severe conditions. A major conclusion of the co-ordinated research programme was that it was not possible to recommend one method as a reference method for in situ testing of high efficiency particulate air filters. Most of the present conventional methods are adequate for current requirements. The reasons why no method is to be recommended were multiple, ranging from economical aspects, through incompatibility of materials to national regulations

  1. Preliminary field evaluation of high efficiency steel filters

    Energy Technology Data Exchange (ETDEWEB)

    Bergman, W.; Larsen, G.; Lopez, R. [Lawrence Livermore National Laboratory, CA (United States)] [and others

    1995-02-01

    We have conducted an evaluation of two high efficiency steel filters in the exhaust of an uranium oxide grit blaster at the Y-12 Plant in Oak Ridge Tennessee. The filters were installed in a specially designed filter housing with a reverse air-pulse cleaning system for automatically cleaning the filters in-place. Previous tests conducted on the same filters and housing at LLNL under controlled conditions using Arizona road dust showed good cleanability with reverse air pulses. Two high efficiency steel filters, containing 64 pleated cartridge elements housed in the standard 2` x 2` x 1` HEPA frame, were evaluated in the filter test housing using a 1,000 cfm slip stream containing a high concentration of depleted uranium oxide dust. One filter had the pleated cartridges manufactured to our specifications by the Pall Corporation and the other by Memtec Corporation. Test results showed both filters had a rapid increase in pressure drop with time, and reverse air pulses could not decrease the pressure drop. We suspected moisture accumulation in the filters was the problem since there were heavy rains during the evaluations, and the pressure drop of the Memtec filter decreased dramatically after passing clean, dry air through the filter and after the filter sat idle for one week. Subsequent laboratory tests on a single filter cartridge confirmed that water accumulation in the filter was responsible for the increase in filter pressure drop and the inability to lower the pressure drop by reverse air pulses. No effort was made to identify the source of the water accumulation and correct the problem because the available funds were exhausted.

  2. Analysis and evaluation for practical application of photovoltaic power generation system. Analysis and evaluation for extra-high efficiency solar cells (research on new concentrator modules); Taiyoko hatsuden system jitsuyoka no tame no kaiseki hyoka. Chokokoritsu taiyo denchi no gijutsu kaihatsu no tame no kaiseki hyoka (shingata shuko module)

    Energy Technology Data Exchange (ETDEWEB)

    Tanimoto, J; Sakuta, K; Sawada, S; Yaoita, A [Electrotechnical Laboratory, Tsukuba (Japan)

    1994-12-01

    Described herein are the results of the FY1994 research program for analysis and evaluation of concentrator modules for extra-high efficiency solar cells. The outdoor exposure tests have been under way for 3 years for fluorescent plates, as part of the research program for development of materials and elementary techniques, and essentially no degradation has been observed by the perylene pigment test. Coupling of the fluorescent concentrator and solar cell units is investigated for the coupling position and method, to theoretically analyze geometrical coupling efficiency, where they are coupled at the bottom faces in consideration of easiness of module fabrication. It is demonstrated that a high coupling efficiency can be realized when the cell is sufficiently wide relative to thickness of the fluorescent plate. The coupling method is experimentally examined using transparent silicon gel. A prototype module having the same size as the commercial module (420mm by 960mm) is made on a trial basis, where a total of nine 20mm-thick cells are cut out of a single-crystalline silicon solar cell, 100mm by 100mm in size, and are connected to concentrators at the bottom faces. It shows 2.3 times increased output by the test using a large-area solar simulator. 2 figs.

  3. High-efficiency and flexible generation of vector vortex optical fields by a reflective phase-only spatial light modulator.

    Science.gov (United States)

    Cai, Meng-Qiang; Wang, Zhou-Xiang; Liang, Juan; Wang, Yan-Kun; Gao, Xu-Zhen; Li, Yongnan; Tu, Chenghou; Wang, Hui-Tian

    2017-08-01

    The scheme for generating vector optical fields should have not only high efficiency but also flexibility for satisfying the requirements of various applications. However, in general, high efficiency and flexibility are not compatible. Here we present and experimentally demonstrate a solution to directly, flexibly, and efficiently generate vector vortex optical fields (VVOFs) with a reflective phase-only liquid crystal spatial light modulator (LC-SLM) based on optical birefringence of liquid crystal molecules. To generate the VVOFs, this approach needs in principle only a half-wave plate, an LC-SLM, and a quarter-wave plate. This approach has some advantages, including a simple experimental setup, good flexibility, and high efficiency, making the approach very promising in some applications when higher power is need. This approach has a generation efficiency of 44.0%, which is much higher than the 1.1% of the common path interferometric approach.

  4. Dynamical Origin of Highly Efficient Energy Dissipation in Soft Magnetic Nanoparticles for Magnetic Hyperthermia Applications

    Science.gov (United States)

    Kim, Min-Kwan; Sim, Jaegun; Lee, Jae-Hyeok; Kim, Miyoung; Kim, Sang-Koog

    2018-05-01

    We explore robust magnetization-dynamic behaviors in soft magnetic nanoparticles in single-domain states and find their related high-efficiency energy-dissipation mechanism using finite-element micromagnetic simulations. We also make analytical derivations that provide deeper physical insights into the magnetization dynamics associated with Gilbert damping parameters under applications of time-varying rotating magnetic fields of different strengths and frequencies and static magnetic fields. Furthermore, we find that the mass-specific energy-dissipation rate at resonance in the steady-state regime changes remarkably with the strength of rotating fields and static fields for given damping constants. The associated magnetization dynamics are well interpreted with the help of the numerical calculation of analytically derived explicit forms. The high-efficiency energy-loss power can be obtained using soft magnetic nanoparticles in the single-domain state by tuning the frequency of rotating fields to the resonance frequency; what is more, it is controllable via the rotating and static field strengths for a given intrinsic damping constant. We provide a better and more efficient means of achieving specific loss power that can be implemented in magnetic hyperthermia applications.

  5. Development of high-efficiency solar cells and modules. Optimised production processes and more durable modules can reduce the costs for producing solar power by a third; Hocheffiziente Solarzellen und Module entwickeln. Optimierte Fertigungsablaeufe und langlebigere Module koennen die Erzeugung von Solarstrom um ein Drittel billiger machen

    Energy Technology Data Exchange (ETDEWEB)

    Hirn, Gerhard

    2013-09-01

    Research institutes, photovoltaic producers, system manufacturers and solar industry suppliers are working together to produce more powerful and durable modules in a more efficient manner. In the SONNE project, companies and researchers are optimising the output and production of modules made of crystalline silicon cells, whereby they are covering the entire production chain and are making the new developments ready for production in a short time. With their developments they want to reduce the costs of solar power by a third.

  6. Development in fiscal 1999 of technologies to put photovoltaic power generation systems into practical use. Development of technologies to manufacture ultra-high efficiency crystalline compound solar cells; 1999 nendo taiyoko hatsuden system jitsuyoka gijutsu kaihatsu seika hokokusho. Chokokoritsu kessho kagobutsu taiyo denchi no seizo gijutsu kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-03-01

    Research and development has been performed on laminated cells comprising of GaInP/GaAs//GaInAs using poly-element compound semiconductors. This paper summarizes the achievements in fiscal 1999. In developing the technology to manufacture large-area ultra-high efficiency cells, fabrication of 5-cm square GaAs cells was worked on, and a conversion efficiency of 24.7%, which is equivalent or better than that for 1-cm square cell, was achieved by using the epitaxial growth temperature for the GaAs cell structure of 600 degrees C, by adopting the p-on-p structure and by making the electrode thicker by using the plating method. Furthermore, trial fabrication was performed on 5-cm square cells also on GaInAs as the bottom cell. A conversion efficiency of 4.6% was obtained in a 5-cm square cell as a result of high level homogenization of film thickness and composition by optimizing the gas flow in growing GaInAs onto an InP substrate, and using a growth temperature of 550 degrees C. In developing the technology to form GaInP/GaAs laminated cells, discussions were given by using 5-mm square cells on especially improving the GaInP crystallinity and reducing the series resistance in the window layer. GaInP/GaAs-2 bonded lamination cells were fabricated, whereas a conversion efficiency of 19.63% was obtained without using a reflection preventing film. (NEDO)

  7. High-efficiency frequency doubling of continuous-wave laser light.

    Science.gov (United States)

    Ast, Stefan; Nia, Ramon Moghadas; Schönbeck, Axel; Lastzka, Nico; Steinlechner, Jessica; Eberle, Tobias; Mehmet, Moritz; Steinlechner, Sebastian; Schnabel, Roman

    2011-09-01

    We report on the observation of high-efficiency frequency doubling of 1550 nm continuous-wave laser light in a nonlinear cavity containing a periodically poled potassium titanyl phosphate crystal (PPKTP). The fundamental field had a power of 1.10 W and was converted into 1.05 W at 775 nm, yielding a total external conversion efficiency of 95±1%. The latter value is based on the measured depletion of the fundamental field being consistent with the absolute values derived from numerical simulations. According to our model, the conversion efficiency achieved was limited by the nonperfect mode matching into the nonlinear cavity and by the nonperfect impedance matching for the maximum input power available. Our result shows that cavity-assisted frequency conversion based on PPKTP is well suited for low-decoherence frequency conversion of quantum states of light.

  8. High Efficiency, Low Cost Parabolic Dish System for Cogeneration of Electricity and Heat

    Science.gov (United States)

    Chayet, Haim; Lozovsky, Ilan; Kost, Ori; Loeckenhoff, Ruediger; Rasch, Klaus-Dieter

    2010-10-01

    Highly efficient combined heat and power generating system based on CPV technology using unique dish design consisting of multiple simple flat mirrors mounted on a plastic parabolic surface. The dish of total aperture area of 11 m2 focuses 10.3 kWp onto a heat and electricity generating receiver. The receiver comprises a water cooled, dense triple junction cell array of 176 cm2 aperture area. A unique arrangement of the cells compensates for the non-uniformity of the reflected flux. Depending on the flow rate, the temperature of the hot water can be adjusted to suit from temperatures for domestic use, to temperatures suited for process heat. The output of 2.3 kWp electrical and 5.5 kWp thermal power from one dish system represent 20 to 21% electrical and 50% thermal conversion efficiency adding to 70% overall system efficiency.

  9. Nonlinear vibration analysis of the high-efficiency compressive-mode piezoelectric energy harvester

    Science.gov (United States)

    Yang, Zhengbao; Zu, Jean

    2015-04-01

    Power source is critical to achieve independent and autonomous operations of electronic mobile devices. The vibration-based energy harvesting is extensively studied recently, and recognized as a promising technology to realize inexhaustible power supply for small-scale electronics. Among various approaches, the piezoelectric energy harvesting has gained the most attention due to its high conversion efficiency and simple configurations. However, most of piezoelectric energy harvesters (PEHs) to date are based on bending-beam structures and can only generate limited power with a narrow working bandwidth. The insufficient electric output has greatly impeded their practical applications. In this paper, we present an innovative lead zirconate titanate (PZT) energy harvester, named high-efficiency compressive-mode piezoelectric energy harvester (HC-PEH), to enhance the performance of energy harvesters. A theoretical model was developed analytically, and solved numerically to study the nonlinear characteristics of the HC-PEH. The results estimated by the developed model agree well with the experimental data from the fabricated prototype. The HC-PEH shows strong nonlinear responses, favorable working bandwidth and superior power output. Under a weak excitation of 0.3 g (g = 9.8 m/s2), a maximum power output 30 mW is generated at 22 Hz, which is about ten times better than current energy harvesters. The HC-PEH demonstrates the capability of generating enough power for most of wireless sensors.

  10. The thermodynamic characteristics of high efficiency, internal-combustion engines

    International Nuclear Information System (INIS)

    Caton, Jerald A.

    2012-01-01

    Highlights: ► The thermodynamics of an automotive engine are determined using a cycle simulation. ► The net indicated thermal efficiency increased from 37.0% to 53.9%. ► High compression ratio, lean mixtures and high EGR were the important features. ► Efficiency increased due to lower heat losses, and increased work conversion. ► The nitric oxides were essentially zero due to the low combustion temperatures. - Abstract: Recent advancements have demonstrated new combustion modes for internal combustion engines that exhibit low nitric oxide emissions and high thermal efficiencies. These new combustion modes involve various combinations of stratification, lean mixtures, high levels of EGR, multiple injections, variable valve timings, two fuels, and other such features. Although the exact combination of these features that provides the best design is not yet clear, the results (low emissions with high efficiencies) are of major interest. The current work is directed at determining some of the fundamental thermodynamic reasons for the relatively high efficiencies and to quantify these factors. Both the first and second laws are used in this assessment. An automotive engine (5.7 l) which included some of the features mentioned above (e.g., high compression ratios, lean mixtures, and high EGR) was evaluated using a thermodynamic cycle simulation. These features were examined for a moderate load (bmep = 900 kPa), moderate speed (2000 rpm) condition. By the use of lean operation, high EGR levels, high compression ratio and other features, the net indicated thermal efficiency increased from 37.0% to 53.9%. These increases are explained in a step-by-step fashion. The major reasons for these improvements include the higher compression ratio and the dilute charge (lean mixture, high EGR). The dilute charge resulted in lower temperatures which in turn resulted in lower heat loss. In addition, the lower temperatures resulted in higher ratios of the specific heats which

  11. Second Generation Advanced Reburning for High Efficiency NOx Control

    International Nuclear Information System (INIS)

    Zamansky, Vladimir M.; Maly, Peter M.; Sheldon, Mark; Seeker, W. Randall; Folsom, Blair A.

    1997-01-01

    Energy and Environmental Research Corporation is developing a family of high efficiency and low cost NO x control technologies for coal fired utility boilers based on Advanced Reburning (AR), a synergistic integration of basic reburning with injection of an N-agent. In conventional AR, injection of the reburn fuel is followed by simultaneous N-agent and overfire air injection. The second generation AR systems incorporate several components which can be used in different combinations. These components include: (1) Reburning Injection of the reburn fuel and overfire air. (2) N-agent Injection The N-agent (ammonia or urea) can be injected at different locations: into the reburning zone, along with the overfire air, and downstream of the overfire air injection. (3) N-agent Promotion Several sodium compounds can considerably enhance the NO x control from N-agent injection. These ''promoters'' can be added to aqueous N-agents. (4) Two Stages of N-agent Injection and Promotion Two N-agents with or without promoters can be injected at different locations for deeper NO x control. AR systems are intended for post-RACT applications in ozone non-attainment areas where NO x control in excess of 80% is required. AR will provide flexible installations that allow NO x levels to be lowered when regulations become more stringent. The total cost of NO x control for AR systems is approximately half of that for SCR. Experimental and kinetic modeling results for development of these novel AR systems are presented. Tests have been conducted in a 1.0 MMBtu/hr Boiler Simulator Facility with coal as the main fuel and natural gas as the reburning fuel. The results show that high efficiency NO x control, in the range 84-95%, can be achieved with various elements of AR. A comparative byproduct emission study was performed to compare the emissions from different variants of AR with commercial technologies (reburning and SNCR). For each technology sampling included: CO, SO 2 , N 2 O, total

  12. Environment-friendly type energy and coordinated community development project. Feasibility study for industrialization of high efficiency waste-fired power generation system using animal waste; Kankyo chowagata energy community keisei sokushin. Kokoritsu haikibutsu hatsuden (chikusan haikibutsu riyo) jigyoka FS chosa

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-03-01

    To introduce the power generation system fueled by animal waste (excrements), one of the so-called industrial waste, its feasibility has been studied in Koyu and surrounding area located in Miyazaki Prefecture. This report includes the technical feasibility of available quantity of animal waste, chemical analysis of the waste, and basic design of the power generation system containing the furnace model and also its economical feasibility. The available quantity of animal waste in Koyu area is about 169,000 tons a year, which can generate 10.5 MW of electric power. That including the surrounding area is about 219,000 tons a year, which can generate 15.0 MW. The heating values of animal excrements in average and as received are 970 kcal/kg for pigs and 1,230 to 2,700 kcal/kg for broilers. In the case of combustion of mixed broiler and pig excrements, both of the stoker and fluidized-bed model furnaces become refractory furnace construction and provide with heat recovery boiler due to their high moisture content. In addition, the stoker furnace model requires an excrement dryer system as pre-treatment of fuel. For the fluidized-bed furnace of 15 MW grade power plant using the mixed fuel of 50% broiler excrements and 50% pig excrements, the power generation efficiency of 23% can be expected at generator end. The generating cost is around 10 yen/kWh. 27 refs., 61 tabs.

  13. In-situ high efficiency filter testing at AEE Winfrith

    International Nuclear Information System (INIS)

    Fraser, D.C.

    1977-01-01

    This paper discusses experience in the testing of high efficiency filters in a variety of reactor and plant installations at AEE Winfrith. There is rarely any concern about the effectiveness of the filter as supplied by any reputable manufacturer. Experience has shown there is a need to check for defects in the installation of filters which could lead to by-passing of aerosols and it is desirable to perform periodical re-tests to ensure that no subsequent deterioration occurs. It is important to use simple, portable apparatus for such tests; methods based on the use of sodium chloride aerosols, although suitable for the testing of filters prior to installation, involve apparatus which is too bulky for in-situ testing. At Winfrith a double automatic Pollak counter has been developed and used routinely since 1970. The aerosol involved has a particle size far smaller than the size most likely to penetrate intact filters, but this is irrelevant when one is primarily interested in particles which by-pass the filter. Comparisons with other methods of testing filters will be described. There is remarkably good agreement between the efficiency of the filter installation as measured by a Pollak counter compared with techniques involving aerosols of sodium chloride and Dioctyl Phthalate (DOP), presumably because the leakage around the filter is independent of particle size

  14. MXene molecular sieving membranes for highly efficient gas separation.

    Science.gov (United States)

    Ding, Li; Wei, Yanying; Li, Libo; Zhang, Tao; Wang, Haihui; Xue, Jian; Ding, Liang-Xin; Wang, Suqing; Caro, Jürgen; Gogotsi, Yury

    2018-01-11

    Molecular sieving membranes with sufficient and uniform nanochannels that break the permeability-selectivity trade-off are desirable for energy-efficient gas separation, and the arising two-dimensional (2D) materials provide new routes for membrane development. However, for 2D lamellar membranes, disordered interlayer nanochannels for mass transport are usually formed between randomly stacked neighboring nanosheets, which is obstructive for highly efficient separation. Therefore, manufacturing lamellar membranes with highly ordered nanochannel structures for fast and precise molecular sieving is still challenging. Here, we report on lamellar stacked MXene membranes with aligned and regular subnanometer channels, taking advantage of the abundant surface-terminating groups on the MXene nanosheets, which exhibit excellent gas separation performance with H 2 permeability >2200 Barrer and H 2 /CO 2 selectivity >160, superior to the state-of-the-art membranes. The results of molecular dynamics simulations quantitatively support the experiments, confirming the subnanometer interlayer spacing between the neighboring MXene nanosheets as molecular sieving channels for gas separation.

  15. High-Efficient Parallel CAVLC Encoders on Heterogeneous Multicore Architectures

    Directory of Open Access Journals (Sweden)

    H. Y. Su

    2012-04-01

    Full Text Available This article presents two high-efficient parallel realizations of the context-based adaptive variable length coding (CAVLC based on heterogeneous multicore processors. By optimizing the architecture of the CAVLC encoder, three kinds of dependences are eliminated or weaken, including the context-based data dependence, the memory accessing dependence and the control dependence. The CAVLC pipeline is divided into three stages: two scans, coding, and lag packing, and be implemented on two typical heterogeneous multicore architectures. One is a block-based SIMD parallel CAVLC encoder on multicore stream processor STORM. The other is a component-oriented SIMT parallel encoder on massively parallel architecture GPU. Both of them exploited rich data-level parallelism. Experiments results show that compared with the CPU version, more than 70 times of speedup can be obtained for STORM and over 50 times for GPU. The implementation of encoder on STORM can make a real-time processing for 1080p @30fps and GPU-based version can satisfy the requirements for 720p real-time encoding. The throughput of the presented CAVLC encoders is more than 10 times higher than that of published software encoders on DSP and multicore platforms.

  16. Novel Intermode Prediction Algorithm for High Efficiency Video Coding Encoder

    Directory of Open Access Journals (Sweden)

    Chan-seob Park

    2014-01-01

    Full Text Available The joint collaborative team on video coding (JCT-VC is developing the next-generation video coding standard which is called high efficiency video coding (HEVC. In the HEVC, there are three units in block structure: coding unit (CU, prediction unit (PU, and transform unit (TU. The CU is the basic unit of region splitting like macroblock (MB. Each CU performs recursive splitting into four blocks with equal size, starting from the tree block. In this paper, we propose a fast CU depth decision algorithm for HEVC technology to reduce its computational complexity. In 2N×2N PU, the proposed method compares the rate-distortion (RD cost and determines the depth using the compared information. Moreover, in order to speed up the encoding time, the efficient merge SKIP detection method is developed additionally based on the contextual mode information of neighboring CUs. Experimental result shows that the proposed algorithm achieves the average time-saving factor of 44.84% in the random access (RA at Main profile configuration with the HEVC test model (HM 10.0 reference software. Compared to HM 10.0 encoder, a small BD-bitrate loss of 0.17% is also observed without significant loss of image quality.

  17. EUROGAM: A high efficiency escape suppressed spectrometer array

    Energy Technology Data Exchange (ETDEWEB)

    Nolan, P J [Liverpool Univ. (United Kingdom). Oliver Lodge Lab.

    1992-08-01

    EUROGAM is a UK-France collaboration to develop and build a high efficiency escape suppressed spectrometer array. The project has involved the development of both germanium (Ge) and bismuth germanate (BGO) detectors to produce crystals which are both bigger and have a more complex geometry. As a major investment for the future, the collaboration has developed a new electronics and data acquisition system based on the VXI and VME standards. The array will start its experimental programme in mid 1992 at the Nuclear Structure Facility at Daresbury, U.K. At this stage it will have a total photopeak efficiency (for 1.33 MeV gamma-rays) of {approx} 4.5%. This will give an improvement in sensitivity (relative to presently operating arrays) of a factor of about 10. When EUROGAM moves to France in mid 1993 its photopeak efficiency will have increased to about 8.5% which will result in an increase in sensitivity of a further factor of about 10. In this article I will concentrate on the array which will operate at Daresbury in 1992 and only briefly cover the developments which will take place for the full array before it is used in France in 1993. (author). 13 refs., 2 tabs., 10 figs.

  18. High Efficiency Hydrodynamic DNA Fragmentation in a Bubbling System.

    Science.gov (United States)

    Li, Lanhui; Jin, Mingliang; Sun, Chenglong; Wang, Xiaoxue; Xie, Shuting; Zhou, Guofu; van den Berg, Albert; Eijkel, Jan C T; Shui, Lingling

    2017-01-18

    DNA fragmentation down to a precise fragment size is important for biomedical applications, disease determination, gene therapy and shotgun sequencing. In this work, a cheap, easy to operate and high efficiency DNA fragmentation method is demonstrated based on hydrodynamic shearing in a bubbling system. We expect that hydrodynamic forces generated during the bubbling process shear the DNA molecules, extending and breaking them at the points where shearing forces are larger than the strength of the phosphate backbone. Factors of applied pressure, bubbling time and temperature have been investigated. Genomic DNA could be fragmented down to controllable 1-10 Kbp fragment lengths with a yield of 75.30-91.60%. We demonstrate that the ends of the genomic DNAs generated from hydrodynamic shearing can be ligated by T4 ligase and the fragmented DNAs can be used as templates for polymerase chain reaction. Therefore, in the bubbling system, DNAs could be hydrodynamically sheared to achieve smaller pieces in dsDNAs available for further processes. It could potentially serve as a DNA sample pretreatment technique in the future.

  19. A Novel High Efficiency Fractal Multiview Video Codec

    Directory of Open Access Journals (Sweden)

    Shiping Zhu

    2015-01-01

    Full Text Available Multiview video which is one of the main types of three-dimensional (3D video signals, captured by a set of video cameras from various viewpoints, has attracted much interest recently. Data compression for multiview video has become a major issue. In this paper, a novel high efficiency fractal multiview video codec is proposed. Firstly, intraframe algorithm based on the H.264/AVC intraprediction modes and combining fractal and motion compensation (CFMC algorithm in which range blocks are predicted by domain blocks in the previously decoded frame using translational motion with gray value transformation is proposed for compressing the anchor viewpoint video. Then temporal-spatial prediction structure and fast disparity estimation algorithm exploiting parallax distribution constraints are designed to compress the multiview video data. The proposed fractal multiview video codec can exploit temporal and spatial correlations adequately. Experimental results show that it can obtain about 0.36 dB increase in the decoding quality and 36.21% decrease in encoding bitrate compared with JMVC8.5, and the encoding time is saved by 95.71%. The rate-distortion comparisons with other multiview video coding methods also demonstrate the superiority of the proposed scheme.

  20. High-efficiency target-ion sources for RIB generation

    International Nuclear Information System (INIS)

    Alton, G.D.

    1993-01-01

    A brief review is given of high-efficiency ion sources which have been developed or are under development at ISOL facilities which show particular promise for use at existing, future, or radioactive ion beam (RIB) facilities now under construction. Emphasis will be placed on those sources which have demonstrated high ionization efficiency, species versatility, and operational reliability and which have been carefully designed for safe handling in the high level radioactivity radiation fields incumbent at such facilities. Brief discussions will also be made of the fundamental processes which affect the realizable beam intensities in target-ion sources. Among the sources which will be reviewed will be selected examples of state-of-the-art electron-beam plasma-type ion sources, thermal-ionization, surface-ionization, ECR, and selectively chosen ion source concepts which show promise for radioactive ion beam generation. A few advanced, chemically selective target-ion sources will be described, such as sources based on the use of laser-resonance ionization, which, in principle, offer a more satisfactory solution to isobaric contamination problems than conventional electromagnetic techniques. Particular attention will be given to the sources which have been selected for initial or future use at the Holifield Radioactive Ion Beam Facility now under construction at the Oak Ridge National Laboratory

  1. High efficiency video coding (HEVC) algorithms and architectures

    CERN Document Server

    Budagavi, Madhukar; Sullivan, Gary

    2014-01-01

    This book provides developers, engineers, researchers and students with detailed knowledge about the High Efficiency Video Coding (HEVC) standard. HEVC is the successor to the widely successful H.264/AVC video compression standard, and it provides around twice as much compression as H.264/AVC for the same level of quality. The applications for HEVC will not only cover the space of the well-known current uses and capabilities of digital video – they will also include the deployment of new services and the delivery of enhanced video quality, such as ultra-high-definition television (UHDTV) and video with higher dynamic range, wider range of representable color, and greater representation precision than what is typically found today. HEVC is the next major generation of video coding design – a flexible, reliable and robust solution that will support the next decade of video applications and ease the burden of video on world-wide network traffic. This book provides a detailed explanation of the various parts ...

  2. EUROGAM: A high efficiency escape suppressed spectrometer array

    International Nuclear Information System (INIS)

    Nolan, P.J.

    1992-01-01

    EUROGAM is a UK-France collaboration to develop and build a high efficiency escape suppressed spectrometer array. The project has involved the development of both germanium (Ge) and bismuth germanate (BGO) detectors to produce crystals which are both bigger and have a more complex geometry. As a major investment for the future, the collaboration has developed a new electronics and data acquisition system based on the VXI and VME standards. The array will start its experimental programme in mid 1992 at the Nuclear Structure Facility at Daresbury, U.K. At this stage it will have a total photopeak efficiency (for 1.33 MeV gamma-rays) of ∼ 4.5%. This will give an improvement in sensitivity (relative to presently operating arrays) of a factor of about 10. When EUROGAM moves to France in mid 1993 its photopeak efficiency will have increased to about 8.5% which will result in an increase in sensitivity of a further factor of about 10. In this article I will concentrate on the array which will operate at Daresbury in 1992 and only briefly cover the developments which will take place for the full array before it is used in France in 1993. (author). 13 refs., 2 tabs., 10 figs

  3. Characterization of three high efficiency and blue sensitive silicon photomultipliers

    Energy Technology Data Exchange (ETDEWEB)

    Otte, Adam Nepomuk, E-mail: otte@gatech.edu; Garcia, Distefano; Nguyen, Thanh; Purushotham, Dhruv

    2017-02-21

    We report about the optical and electrical characterization of three high efficiency and blue sensitive Silicon photomultipliers from FBK, Hamamatsu, and SensL. Key features of the tested devices when operated at 90% breakdown probability are peak photon detection efficiencies between 40% and 55%, temperature dependencies of gain and PDE that are less than 1%/°C, dark rates of ∼50 kHz/mm{sup 2} at room temperature, afterpulsing of about 2%, and direct optical crosstalk between 6% and 20%. The characteristics of all three devices impressively demonstrate how the Silicon-photomultiplier technology has improved over the past ten years. It is further demonstrated how the voltage and temperature characteristics of a number of quantities can be parameterized on the basis of physical models. The models provide a deeper understanding of the device characteristics over a wide bias and temperature range. They also serve as examples how producers could provide the characteristics of their SiPMs to users. A standardized parameterization of SiPMs would enable users to find the optimal SiPM for their application and the operating point of SiPMs without having to perform measurements thus significantly reducing design and development cycles.

  4. Thin Film Packaging Solutions for High Efficiency OLED Lighting Products

    Energy Technology Data Exchange (ETDEWEB)

    None

    2008-06-30

    The objective of the 'Thin Film Packaging Solutions for High Efficiency OLED Lighting Products' project is to demonstrate thin film packaging solutions based on SiC hermetic coatings that, when applied to glass and plastic substrates, support OLED lighting devices by providing longer life with greater efficiency at lower cost than is currently available. Phase I Objective: Demonstrate thin film encapsulated working phosphorescent OLED devices on optical glass with lifetime of 1,000 hour life, CRI greater than 75, and 15 lm/W. Phase II Objective: Demonstrate thin film encapsulated working phosphorescent OLED devices on plastic or glass composite with 25 lm/W, 5,000 hours life, and CRI greater than 80. Phase III Objective: Demonstrate 2 x 2 ft{sup 2} thin film encapsulated working phosphorescent OLED with 40 lm/W, 10,000 hour life, and CRI greater than 85. This report details the efforts of Phase III (Budget Period Three), a fourteen month collaborative effort that focused on optimization of high-efficiency phosphorescent OLED devices and thin-film encapsulation of said devices. The report further details the conclusions and recommendations of the project team that have foundation in all three budget periods for the program. During the conduct of the Thin Film Packaging Solutions for High Efficiency OLED Lighting Products program, including budget period three, the project team completed and delivered the following achievements: (1) a three-year marketing effort that characterized the near-term and longer-term OLED market, identified customer and consumer lighting needs, and suggested prototype product concepts and niche OLED applications lighting that will give rise to broader market acceptance as a source for wide area illumination and energy conservation; (2) a thin film encapsulation technology with a lifetime of nearly 15,000 hours, tested by calcium coupons, while stored at 16 C and 40% relative humidity ('RH'). This encapsulation technology

  5. Highly Efficient Spectrally Stable Red Perovskite Light-Emitting Diodes.

    Science.gov (United States)

    Tian, Yu; Zhou, Chenkun; Worku, Michael; Wang, Xi; Ling, Yichuan; Gao, Hanwei; Zhou, Yan; Miao, Yu; Guan, Jingjiao; Ma, Biwu

    2018-05-01

    Perovskite light-emitting diodes (LEDs) have recently attracted great research interest for their narrow emissions and solution processability. Remarkable progress has been achieved in green perovskite LEDs in recent years, but not blue or red ones. Here, highly efficient and spectrally stable red perovskite LEDs with quasi-2D perovskite/poly(ethylene oxide) (PEO) composite thin films as the light-emitting layer are reported. By controlling the molar ratios of organic salt (benzylammonium iodide) to inorganic salts (cesium iodide and lead iodide), luminescent quasi-2D perovskite thin films are obtained with tunable emission colors from red to deep red. The perovskite/polymer composite approach enables quasi-2D perovskite/PEO composite thin films to possess much higher photoluminescence quantum efficiencies and smoothness than their neat quasi-2D perovskite counterparts. Electrically driven LEDs with emissions peaked at 638, 664, 680, and 690 nm have been fabricated to exhibit high brightness and external quantum efficiencies (EQEs). For instance, the perovskite LED with an emission peaked at 680 nm exhibits a brightness of 1392 cd m -2 and an EQE of 6.23%. Moreover, exceptional electroluminescence spectral stability under continuous device operation has been achieved for these red perovskite LEDs. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. FY 2001 report on the results of the survey of the environmentally friendly type energy community project. Utilization of combustible waste as solid fuel in Shimizu City, Shizuoka Prefecture, and the wide spread sphere of municipalities (Facilities such as RDF+LNG combined use high efficiency waste power generation); 2001 nendo Shizuoka ken shimizu shi oyobi koiki shichoson ken ni okeru kanensei haikibutsu kokeika nenryo riyo kankyo chowa gata energy komyuniti keisei sokushin hojo jigyo chosa (RDF+LNG heiyo kokoritsu haikibutsu hatsuden tou shisetsu) chosa hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-03-01

    Survey/study were conducted of viability of an idea of the high efficiency power generation that combinedly use RDF from the refuse generated in Shizuoka/Yamanashi/Nagano prefectures and LNG from the LNG base in Shimizu City, Shizuoka Prefecture. In the survey of raw materials for RDF, the present amount that can be supplied to RDF power generation was estimated at 280 t/d in RDF and 4,300 Kcal/kg or more in heating value. As to the RDF/LNG combination power generation, combinations of RDF200t/d + 25MW (capacity of gas turbine power generation) or RDF200t/d + 70MW seem to be appropriate. And, 30% or more of RDF power generation efficiency is made possible. In the study of economical efficiency, expenses born by local governments were calculated supposing that the difference between the unit price of power selling and that of power generation in power generation is born by RDF suppliers. As a result, the share becomes approximately 8,600-12,000 yen/refuse t in 15-year operation, and was found lower than that in the existing small-/medium-scale refuse incineration treatment. The combustion flue gas associated with the power generation business becomes approximately 300,000 Nm{sup 3}/h. The gas turbine fuel is natural gas, and RDF is good in combustibility. Therefore, the effect on the environment is expected to be small. (NEDO)

  7. Environment-friendly type energy and coordinated community development project. Feasibility study for industrialization of high efficiency waste-fired power generation system using general RDF; Kankyo chowagata energy community keisei sokushin. Kokoritsu haikibutsu hatsuden (ippainado RDF riyo) jigyoka FS chosa

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-03-01

    The refuse-derived fuel (RDF) has been holding public attention not only as the energy resource of stable high calorific value for local energy development, but also as the effective method for waste treatment. As one of the effective utilization methods for waste treatment, this investigation was conducted to industrialize and establish the RDF power generation system, in which power generation and ash treatment are integrated in Tochigi Prefecture which is located inland. The base supply type was adopted as a way of operation from the menu of the electricity wholesale project of Tokyo Electric Power Co. and its rate of operation is 80 percent a year. Then, the fluidized bed combustion method, a dry exhaust gas treatment method, and continuous electric melting furnaces were decided as the RDF power generation system. According to this system, it is possible to obtain 26 percent gross thermal efficiency by conventional generation facilities. It was estimated that the expenses reduction for 15 years will be 17.6 billion yen compared with the ordinary combustion system. Also, the following effects can be expected; the reduction of CO2 emission, improvement of energy efficiency, and the extension of life of landfills capacity. 36 figs., 51 tabs.

  8. High-efficiency integrated piezoelectric energy harvesting systems

    Science.gov (United States)

    Hande, Abhiman; Shah, Pradeep

    2010-04-01

    This paper describes hierarchically architectured development of an energy harvesting (EH) system that consists of micro and/or macro-scale harvesters matched to multiple components of remote wireless sensor and communication nodes. The micro-scale harvesters consist of thin-film MEMS piezoelectric cantilever arrays and power generation modules in IC-like form to allow efficient EH from vibrations. The design uses new high conversion efficiency thin-film processes combined with novel cantilever structures tuned to multiple resonant frequencies as broadband arrays. The macro-scale harvesters are used to power the collector nodes that have higher power specifications. These bulk harvesters can be integrated with efficient adaptive power management circuits that match transducer impedance and maximize power harvested from multiple scavenging sources with very low intrinsic power consumption. Texas MicroPower, Inc. is developing process based on a composition that has the highest reported energy density as compared to other commercially available bulk PZT-based sensor/actuator ceramic materials and extending it to thin-film materials and miniature conversion transducer structures. The multiform factor harvesters can be deployed for several military and commercial applications such as underground unattended sensors, sensors in oil rigs, structural health monitoring, supply chain management, and battlefield applications such as sensors on soldier apparel, equipment, and wearable electronics.

  9. A high efficiency photovoltaic module integrated converter with the asymmetrical half-bridge flyback converter

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Heeje; Kim, Jongrak; Shin, Dongsul [Department of Electrical Engineering, Pusan National University, Jangjeon, Geumjeong, Busan 609-735 (Korea); Kim, Hosung; Lee, Kyungjun [Department of Electrical Engineering, Pusan National University, Jangjeon, Geumjeong, Busan 609-735 (Korea); New and Renewable Energy System Research Center, Korea Electro-technology Research Institute, 28-1, Sungju-dong Changwon-si, Kyungsannam-do, 641-120 (Korea); Kim, Jonghyun; Yoo, Dongwook [New and Renewable Energy System Research Center, Korea Electro-technology Research Institute, 28-1, Sungju-dong Changwon-si, Kyungsannam-do, 641-120 (Korea)

    2010-08-15

    A module integrated converter (MIC) for a photovoltaic (PV) cell is important part of power conditioning system (PCS). It performs maximum power point tracking of a PV cell to generate the power as much as possible from solar energy. There are several methods for connection between the PV modules and the MICs. In order to avoid partial shading effects, converter-per-module approach was proposed. The MIC that performs maximum power point tracking (MPPT), if it is low efficiency, is no use. The MIC whose output is connected to the output of PV module was proposed for high efficiency. However, there are some problems. In this study, an asymmetrical half-bridge flyback converter is proposed instead of the original flyback converter with same method to solve the problems. The proposed MIC was built to verify the performance. The new topology using soft switching technique showed good performance for the efficiency. At the higher power, the efficiency of the proposed converter is higher than existing converter. (author)

  10. Highly efficient distributed generation and high-capacity energy storage

    DEFF Research Database (Denmark)

    Hemmes, Kas; Guerrero, Josep M.; Zhelev, Toshko

    2012-01-01

    With the growing amount of decentralized power production the design and operation of the grid has to be reconsidered. New problems include the two-way flow of electricity and maintaining the power balance given the increased amount of uncertain and fluctuating renewable energy sources like wind...... and solar that deliver electricity to the grid. Solution directions are the development of smart grids, demand side management, virtual power plants and storage of electricity. These are directions that, rightly so, are already attracting a lot of attention and R&D funding. In this paper critical issues...... and fuel that can also fulfill a storage function....

  11. High Efficiency Microchannel Diamond Heat Sinks, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — While absolute power levels in microelectronic devices are relatively modest (a few tens to a few hundred watts), heat fluxes can be significant (~50 W/cm2 in...

  12. Spectral beam combining of diode lasers with high efficiency

    DEFF Research Database (Denmark)

    Müller, André; Vijayakumar, Deepak; Jensen, Ole Bjarlin

    2012-01-01

    Based on spectral beam combining we obtain 16 W of output power, combining two 1063 nm DBR-tapered diode lasers. The spectral separation within the combined beam can be used for subsequent sum-frequency generation.......Based on spectral beam combining we obtain 16 W of output power, combining two 1063 nm DBR-tapered diode lasers. The spectral separation within the combined beam can be used for subsequent sum-frequency generation....

  13. Light-induced lattice expansion leads to high-efficiency perovskite solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Tsai, Hsinhan; Asadpour, Reza; Blancon, Jean-Christophe; Stoumpos, Constantinos C.; Durand, Olivier; Strzalka, Joseph W.; Chen, Bo; Verduzco, Rafael; Ajayan, Pulickel M.; Tretiak, Sergei; Even, Jacky; Alam, Muhammad Ashraf; Kanatzidis, Mercouri G.; Nie, Wanyi; Mohite, Aditya D.

    2018-04-05

    Hybrid-perovskite based high-performance optoelectronic devices and clues from their operation has led to the realization that light-induced structural dynamics play a vital role on their physical properties, device performance and stability. Here, we report that continuous light illumination leads to a uniform lattice expansion in hybrid perovskite thin-films, which is critical for obtaining high-efficiency photovoltaic devices. Correlated, in-situ structural and device characterizations reveal that light-induced lattice expansion significantly benefits the performances of a mixed-cation pure-halide planar device, boosting the power conversion efficiency from 18.5% to 20.5%. This is a direct consequence of the relaxation of local lattice strains during lattice expansion, which results in the reduction of the energetic barriers at the perovskite/contact interfaces in devices, thus improving the open circuit voltage and fill factor. The light-induced lattice expansion stabilizes these high-efficiency photovoltaic devices under continuous operation of full-spectrum 1-Sun illumination for over 1500 hours. One Sentence Summary: Light-induced lattice expansion improves crystallinity, relaxes lattice strain, which enhances photovoltaic performance in hybrid perovskite device.

  14. Polyphenols attached graphene nanosheets for high efficiency NIR mediated photodestruction of cancer cells

    International Nuclear Information System (INIS)

    Abdolahad, M.; Janmaleki, M.; Mohajerzadeh, S.; Akhavan, O.; Abbasi, S.

    2013-01-01

    Green tea-reduced graphene oxide (GT-rGO) sheets have been exploited for high efficiency near infrared (NIR) photothermal therapy of HT29 and SW48 colon cancer cells. The biocompatibility of GT-rGO sheets was investigated by means of MTT assays. The polyphenol constituents of GT-rGO act as effective targeting ligands for the attachment of rGO to the surface of cancer cells, as confirmed by the cell granularity test in flow cytometry assays and also by scanning electron microscopy. The photo-thermal destruction of higher metastatic cancer cells (SW48) is found to be more than 20% higher than that of the lower metastatic one (HT29). The photo-destruction efficiency factor of the GT-rGO is found to be at least two orders of magnitude higher than other carbon-based nano-materials. Such excellent cancer cell destruction efficiency provided application of a low concentration of rGO (3 mg/L) and NIR laser power density (0.25 W/cm 2 ) in our photo-thermal therapy of cancer cells. Highlights: ► Attachment of polyphenol groups to graphene nano-sheets during reduction process by green tea. ► Selective attachment of polyphenols to cancer cell membrane. ► High efficiency photothermal therapy of colon cancer cells with green-tea reduced graphene oxide

  15. High-efficiency passive full wave rectification for electromagnetic harvesters

    Science.gov (United States)

    Yilmaz, Mehmet; Tunkar, Bassam A.; Park, Sangtak; Elrayes, Karim; Mahmoud, Mohamed A. E.; Abdel-Rahman, Eihab; Yavuz, Mustafa

    2014-10-01

    We compare the performance of four types of full-wave bridge rectifiers designed for electromagnetic energy harvesters based on silicon diodes, Schottky diodes, passive MOSFETs, and active MOSFETs. Simulation and experimental results show that MOSFET-type rectifiers are more efficient than diode-type rectifiers, reaching voltage and power efficiency of 99% for ideal voltage source with input amplitudes larger than 800 mV. Since active MOSFETs require extra components and an external DC power supply, we conclude that passive MOSFETs are superior for micro-power energy harvesting systems. We demonstrate passive MOSFET rectifiers implemented using discrete, off-shelf components and show that they outperform all electromagnetic harvester rectifiers hitherto reported obtaining a power efficiency of 95%. Furthermore, we show that passive MOSFET rectifiers do not affect the center frequency, harvesting bandwidth, or optimal resistance of electromagnetic harvesters. We demonstrate a complete power management module by adding a capacitor to the rectifier output terminal. We found that this configuration changed the optimal resistive load from 40 Ω to 55 Ω and decreased output power efficiency to 86%.

  16. Hot nuclei studied with high efficiency neutron detectors

    International Nuclear Information System (INIS)

    Galin, J.

    1990-01-01

    We have shown the invaluable benefit that a high efficiency 4π neutron detector can bring to the study of reaction mechanisms following collisions of heavy nuclei at intermediate energy. Analysis requires Monte-Carlo simulations for comparison between experimental data and any emission model. In systematic measurements with projectiles of velocity corresponding to energies between 27 and 77 MeV/u, where both the influence of beam velocity and mass have been investigated separately, it has been shown that the projectile-target mass asymmetry, much more than velocity, has a decisive influence on energy dissipation. The closer the projectile mass to the target mass, the more energy is dissipated per unit mass of the considered projectile plus target system. The latter presents all the characteristics of a thermalized system, evaporating a copious number of light particles: up to about 40 neutrons (after efficiency correction) and 11 light charged particles in the most dissipative collisions between Kr+Au, and 90 neutrons for Pb+U with a yet unknown number of l.c.p. In the Kr experiment, these particles are isotropically emitted in the frame of a fused system, excited with 1.2 GeV. Moreover, l.c.p. exhibit Maxwellian energy distributions as in any standard evaporation process. We are now eager to better characterize the properties of the Pb+Au (U) systems for which about 1/3 of the neutrons are freed in a rather large fraction of all collisions. The thermalized energy should then approach very closely the total binding energy of the two interacting nuclei

  17. A critical study of high efficiency deep grinding

    International Nuclear Information System (INIS)

    Johnstone, Iain

    2002-01-01

    The recent years, the aerospace industry in particular has embraced and actively pursued the development of stronger high performance materials, namely nickel based superalloys and hardwearing steels. This has resulted in a need for a more efficient method of machining, and this need was answered with the advent of High Efficiency Deep Grinding (HEDG). This relatively new process using Cubic Boron Nitride (CBN) electroplated grinding wheels has been investigated through experimental and theoretical means applied to two widely used materials, M50 bearing steel and IN718 nickel based superalloy. It has been shown that this grinding method using a stiff grinding centre such as the Edgetek 5-axis machine is a viable process. Using a number of experimental designs, produced results which were analysed using a variety of methods including visual assessment, sub-surface microscopy and surface analysis using a Scanning Electron Microscope (SEM), residual stress measurement using X-Ray Diffraction (XRD) techniques, Barkhausen Noise Amplitude (BNA) measurements, surface roughness and Vickers micro-hardness appraisal. It has been shown that the fundamentals of the HEDG process have been understood through experimental as well as theoretical means and that through the various thermal models used, grinding temperatures can be predicted to give more control over this dynamic process. The main contributions to knowledge are made up of a number of elements within the grinding environment, the most important being the demonstration of the HEDG effect, explanation of the phenomenon and the ability to model the process. It has also been shown that grinding is a dynamic process and factors such as wheel wear will result in a continuous change in the optimum grinding conditions for a given material and wheel combination. With the significance of these factors recognised, they can be accounted for within an industrial adaptive control scenario with the process engineer confident of a

  18. [Tobacco--a highly efficient producer of vaccines].

    Science.gov (United States)

    Budzianowski, Jaromir

    2010-01-01

    Along with the depreciation of tobacco as a source of nicotine-containing commercial products, the increase of its appreciation as a potential producer of recombinant therapeutical proteins can be observed. Two species of tobacco--Nicotiana tabacum L. and N. benthamiana are easily grown by well established methods of field or green-house cultivation or cell culture, yield high biomass and soluble protein content, can be easily transformed by several methods and are not food for humans or feed for animals. Expression of foreign proteins, including vaccines, can be achieved in those plants either through stable transformation of nuclear or plastid (chloroplast) genomes or by transient transformation using infection with plant virus or bacteria--Agrobacterium tumefaciens (agroinfiltration). The most advanced mode of agrofiltration termed magnifection, which combines benefits of virus and Agrobacterium and depends on using Agrobacterium with viral pro-vectors, enables high-yield and rapid expression of therapeutical proteins, even in a few days, and can be employed on an industrial scale. Expression of many antigenic proteins, which may serve as antiviral, antibacterial, antiprotozoan and anticancer vaccines, and additionally a few autoantigens designed for the treatment of autoimunogenic diseases, like diabetes, have been achieved in tobacco. To date, a vaccine against Newcastle virus disease in poultry produced by tobacco cell culture has been approved for commercial application and several other vaccines are in advanced stage of development. The possibility of a high-level production of vaccines in tobacco against pandemic influenza or anthrax and plague due to a bioterroristic attack, as well as of individualised anticancer vaccines against non-Hodgkin's lymphoma (NHL) in a much shorter period of time than by traditional methods became realistic and hence caused increased interest in tobacco as a high-efficient producer of vaccines not only of specialistic

  19. Progress of High Efficiency Centrifugal Compressor Simulations Using TURBO

    Science.gov (United States)

    Kulkarni, Sameer; Beach, Timothy A.

    2017-01-01

    Three-dimensional, time-accurate, and phase-lagged computational fluid dynamics (CFD) simulations of the High Efficiency Centrifugal Compressor (HECC) stage were generated using the TURBO solver. Changes to the TURBO Parallel Version 4 source code were made in order to properly model the no-slip boundary condition along the spinning hub region for centrifugal impellers. A startup procedure was developed to generate a converged flow field in TURBO. This procedure initialized computations on a coarsened mesh generated by the Turbomachinery Gridding System (TGS) and relied on a method of systematically increasing wheel speed and backpressure. Baseline design-speed TURBO results generally overpredicted total pressure ratio, adiabatic efficiency, and the choking flow rate of the HECC stage as compared with the design-intent CFD results of Code Leo. Including diffuser fillet geometry in the TURBO computation resulted in a 0.6 percent reduction in the choking flow rate and led to a better match with design-intent CFD. Diffuser fillets reduced annulus cross-sectional area but also reduced corner separation, and thus blockage, in the diffuser passage. It was found that the TURBO computations are somewhat insensitive to inlet total pressure changing from the TURBO default inlet pressure of 14.7 pounds per square inch (101.35 kilopascals) down to 11.0 pounds per square inch (75.83 kilopascals), the inlet pressure of the component test. Off-design tip clearance was modeled in TURBO in two computations: one in which the blade tip geometry was trimmed by 12 mils (0.3048 millimeters), and another in which the hub flow path was moved to reflect a 12-mil axial shift in the impeller hub, creating a step at the hub. The one-dimensional results of these two computations indicate non-negligible differences between the two modeling approaches.

  20. High-efficiency condenser of steam from a steam-gas mixture

    Science.gov (United States)

    Milman, O. O.; Krylov, V. S.; Ptakhin, A. V.; Kondratev, A. V.; Yankov, G. G.

    2017-12-01

    The design of a module for a high-efficiency condenser of steam with a high content (up to 15%) of noncondensable gases (NCGs) with a nearly constant steam-gas mixture (SGM) velocity during the condensation of steam has been developed. This module provides the possibility to estimate the operational efficiency of six condenser zones during the motion of steam from the inlet to the SGM suction point. Some results of the experimental tests of the pilot high-efficiency condenser module are presented. The dependence of the average heat transfer coefficient k¯ on the volumetric NCG concentration v¯ has been derived. It is shown that the high-efficiency condenser module can provide a moderate decrease in k¯ from 4400-4600 to 2600-2800 W/(m2 K) at v¯ ≈ 0.5-9.0%. The heat transfer coefficient distribution over different module zones at a heat duty close to its nominal value has been obtained. From this distribution, it can be seen that the average heat transfer coefficient decreases to 2600 W/(m2 K) at an NCG concentration v¯ = 7.5%, but the first condenser sections ( 1- 3) retain high values of k¯ at a level of no lower than 3200 W/(m2 K), and the last sections operate less well, having k¯ at a level of 1700 W/(m2 K). The dependence of the average heat transfer coefficient on the water velocity in condenser tubes has been obtained at a nearly nominal duty such that the extrapolation of this dependence to the water velocity of 2 m/s may be expected to give k¯ = 5000 W/(m2 K) for relatively pure steam, but an increase in k¯ at v¯ = 8% will be smaller. The effect of the gas removal device characteristic on the operation of the high-efficiency condenser module is described. The design developed for the steam condenser of a gas-turbine plant with a power of 25 MW, a steam flow rate of 40.2 t/h, and a CO2 concentration of up to 12% with consideration for the results of performed studies is presented.

  1. High-efficiency photovoltaic technology including thermoelectric generation

    Science.gov (United States)

    Fisac, Miguel; Villasevil, Francesc X.; López, Antonio M.

    2014-04-01

    Nowadays, photovoltaic solar energy is a clean and reliable source for producing electric power. Most photovoltaic systems have been designed and built up for use in applications with low power requirements. The efficiency of solar cells is quite low, obtaining best results in monocrystalline silicon structures, with an efficiency of about 18%. When temperature rises, photovoltaic cell efficiency decreases, given that the short-circuit current is slightly increased, and the open-circuit voltage, fill factor and power output are reduced. To ensure that this does not affect performance, this paper describes how to interconnect photovoltaic and thermoelectric technology into a single structure. The temperature gradient in the solar panel is used to supply thermoelectric cells, which generate electricity, achieving a positive contribution to the total balance of the complete system.

  2. Performance of High-Efficiency Advanced Triple-Junction Solar Panels for the LILT Mission Dawn

    Science.gov (United States)

    Fatemi, Navid S.; Sharma, Surya; Buitrago, Oscar; Sharps, Paul R.; Blok, Ron; Kroon, Martin; Jalink, Cees; Harris, Robin; Stella, Paul; Distefano, Sal

    2005-01-01

    NASA's Discovery Mission Dawn is designed to (LILT) conditions. operate within the solar system's Asteroid belt, where the large distance from the sun creates a low-intensity, low-temperature (LILT) condition. To meet the mission power requirements under LlLT conditions, very high-efficiency multi-junction solar cells were selected to power the spacecraft to be built by Orbital Sciences Corporation (OSC) under contract with JPL. Emcore's InGaP/InGaAs/Ge advanced triple-junction (ATJ) solar cells, exhibiting an average air mass zero (AMO) efficiency of greater than 27.6% (one-sun, 28 C), were used to populate the solar panels [1]. The two solar array wings, to be built by Dutch Space, with 5 large- area panels each (total area of 36.4 sq. meters) are projected to produce between 10.3 kWe and 1.3 kWe of end-of life (EOL) power in the 1.0 to 3.0 AU range, respectively. The details of the solar panel design, testing and power analysis are presented.

  3. Rotating-Sleeve Triboelectric-Electromagnetic Hybrid Nanogenerator for High Efficiency of Harvesting Mechanical Energy.

    Science.gov (United States)

    Cao, Ran; Zhou, Tao; Wang, Bin; Yin, Yingying; Yuan, Zuqing; Li, Congju; Wang, Zhong Lin

    2017-08-22

    Currently, a triboelectric nanogenerator (TENG) and an electromagnetic generator (EMG) have been hybridized to effectively scavenge mechanical energy. However, one critical issue of the hybrid device is the limited output power due to the mismatched output impedance between the two generators. In this work, impedance matching between the TENG and EMG is achieved facilely through commercial transformers, and we put forward a highly integrated hybrid device. The rotating-sleeve triboelectric-electromagnetic hybrid nanogenerator (RSHG) is designed by simulating the structure of a common EMG, which ensures a high efficiency in transferring ambient mechanical energy into electric power. The RSHG presents an excellent performance with a short-circuit current of 1 mA and open-circuit voltage of 48 V at a rotation speed of 250 rpm. Systematic measurements demonstrate that the hybrid nanogenerator can deliver the largest output power of 13 mW at a loading resistance of 8 kΩ. Moreover, it is demonstrated that a wind-driven RSHG can light dozens of light-emitting diodes and power an electric watch. The distinctive structure and high output performance promise the practical application of this rotating-sleeve structured hybrid nanogenerator for large-scale energy conversion.

  4. Completion of a high efficiency ultralarge capacity three-phase transformer

    International Nuclear Information System (INIS)

    Maejima, Masaaki; Maruyama, Katsuya; Fukuda, Teruo.

    1986-01-01

    As for the boosting transformers for thermal and nuclear power stations, at present the ultralarge capacity transformers of 1000 - 1200 MVA class are the main, and particularly in nuclear power, accompanying the development of improved type BWRs and the rise of system stability, there is the tendency toward further large capacity and large size. Consequently, reflecting the recent rise of energy cost, the demand of energy conservation and the reduction of required sites heightened largely as well as the high reliability. In order to meet these demands, Hitachi Ltd. has established the technology of changing to iron machines such as ultralarge iron cores and ultralarge capacity undivided disk windings using the latest design and manufacture techniques were applied to the 525 kV, 1200 MVA transformer for No.4 plant in Fukushima No.2 Nuclear Power Station, Tokyo Electric Power Co., Inc., thus a three-phase transformer of the highest level, high efficiency and ultralarge capacity was completed. In this paper, the outline of this transformer and the test for verifying its reliability are described. The technical change of large capacity three-phase transformers, the specifications, construction, manufacture, reliability test and the effect of modification of this transformer, and the expansion of application to the next generation ultralarge capacity transformers are reported. (Kako, I.)

  5. High Efficiency PFC Frontend for Class-D Amplifiers

    DEFF Research Database (Denmark)

    Li, Qingnan; Frium, Mads P.

    2012-01-01

    This thesis investigates the design of high eciency Power Factor Correction (PFC) converter for Class-D amplier at universal line and 3.5kW power range. The work starts with an overview on dierent high eciency Bridgeless PFC topologies and investigates their applicability with respect to the given...... speci- cations in Chapter 1. Based on the conclusions of Chapter 2, the single-phase Two-Boost-Circuit Bridgeless PFC converter topology is considered the most promising to start with regarding the achievable converter eciency and the EMI performances.The subsequent Chapters discuss the method...

  6. Low Temperature Combustion Demonstrator for High Efficiency Clean Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Ojeda, William de

    2010-07-31

    The project which extended from November 2005 to May of 2010 demonstrated the application of Low Temperature Combustion (LTC) with engine out NOx levels of 0.2 g/bhp-hr throughout the program target load of 12.6bar BMEP. The project showed that the range of loads could be extended to 16.5bar BMEP, therefore matching the reference lug line of the base 2007 MY Navistar 6.4L V8 engine. Results showed that the application of LTC provided a dramatic improvement over engine out emissions when compared to the base engine. Furthermore LTC improved thermal efficiency by over 5% from the base production engine when using the steady state 13 mode composite test as a benchmark. The key enablers included improvements in the air, fuel injection, and cooling systems made in Phases I and II. The outcome was the product of a careful integration of each component under an intelligent control system. The engine hardware provided the conditions to support LTC and the controller provided the necessary robustness for a stable combustion. Phase III provided a detailed account on the injection strategy used to meet the high load requirements. During this phase, the control strategy was implemented in a production automotive grade ECU to perform cycle-by-cycle combustion feedback on each of the engine cylinders. The control interacted on a cycle base with the injection system and with the Turbo-EGR systems according to their respective time constants. The result was a unique system that could, first, help optimize the combustion system and maintain high efficiency, and secondly, extend the steady state results to the transient mode of operation. The engine was upgraded in Phase IV with a Variable Valve Actuation system and a hybrid EGR loop. The impact of the more versatile EGR loop did not provide significant advantages, however the application of VVA proved to be an enabler to further extend the operation of LTC and gain considerable benefits in fuel economy and soot reduction. Finally

  7. Highly efficient DNA extraction method from skeletal remains

    Directory of Open Access Journals (Sweden)

    Irena Zupanič Pajnič

    2011-03-01

    Full Text Available Background: This paper precisely describes the method of DNA extraction developed to acquire high quality DNA from the Second World War skeletal remains. The same method is also used for molecular genetic identification of unknown decomposed bodies in routine forensic casework where only bones and teeth are suitable for DNA typing. We analysed 109 bones and two teeth from WWII mass graves in Slovenia. Methods: We cleaned the bones and teeth, removed surface contaminants and ground the bones into powder, using liquid nitrogen . Prior to isolating the DNA in parallel using the BioRobot EZ1 (Qiagen, the powder was decalcified for three days. The nuclear DNA of the samples were quantified by real-time PCR method. We acquired autosomal genetic profiles and Y-chromosome haplotypes of the bones and teeth with PCR amplification of microsatellites, and mtDNA haplotypes 99. For the purpose of traceability in the event of contamination, we prepared elimination data bases including genetic profiles of the nuclear and mtDNA of all persons who have been in touch with the skeletal remains in any way. Results: We extracted up to 55 ng DNA/g of the teeth, up to 100 ng DNA/g of the femurs, up to 30 ng DNA/g of the tibias and up to 0.5 ng DNA/g of the humerus. The typing of autosomal and YSTR loci was successful in all of the teeth, in 98 % dekalof the femurs, and in 75 % to 81 % of the tibias and humerus. The typing of mtDNA was successful in all of the teeth, and in 96 % to 98 % of the bones. Conclusions: We managed to obtain nuclear DNA for successful STR typing from skeletal remains that were over 60 years old . The method of DNA extraction described here has proved to be highly efficient. We obtained 0.8 to 100 ng DNA/g of teeth or bones and complete genetic profiles of autosomal DNA, Y-STR haplotypes, and mtDNA haplotypes from only 0.5g bone and teeth samples.

  8. A high-efficiency acoustic chamber and the anomalous sample rotation

    Science.gov (United States)

    Wang, Taylor G.; Allen, J. L.

    1992-01-01

    A high efficiency acoustic chamber for the levitation and manipulation of liquid or molten samples in a microgravity environment has been developed. The chamber uses two acoustic drivers that are mounted at opposite corners of the chamber; by driving these at the same frequency, with 18-deg phase shifts, an increase in force of a factor of 3-4 is obtainable relative to the force of a single-driver system that is operated at the same power level. This enhancement is due to the increased coupling between the sound driver and the chamber. An anomalous rotation is noted to be associated with the chamber; this is found to be eliminated by a physically as-yet inexplicable empirical solution.

  9. High efficiency particulate air filter technology from 1980 to 1985 in the Central Electricity Generating Board

    International Nuclear Information System (INIS)

    Skledon, R.; Taylor, S.; Fern, C.; Stead, M.

    1986-01-01

    This paper examines at the Central Electricity Generating Board's methods of High Efficiency Particulate Air (1,700 m 3 /hr) filter testing from conception to the present day. The choice of the test and the early results are looked at followed by the development using new test equipment for checking ladderframe systems. The need for the drawing up of the Central Electricity Generating Board 743401 Standard for filter manufacture and its effect on full implementation is looked into. The advantages and disadvantages of our test procedures are reflected upon and the future developments in test methods and filters for use by the C.E.G.B. in their power stations are discussed. (author)

  10. A simple and highly efficient Agrobacterium-mediated transformation protocol for Setaria viridis

    Directory of Open Access Journals (Sweden)

    Polyana Kelly Martins

    2015-06-01

    Full Text Available The production and use of sugarcane in Brazil is very important for bioenergy production and is recognized as one of the most efficient in the world. In our laboratory, Setaria viridis is being tested as a model plant for sugarcane. S. viridis has biological attributes (rapid life cycle, small genome, diploid, short stature and simple growth requirements that make it suitable for use as a model system. We report a highly efficient protocol for Agrobacterium-mediated genetic transformation of S. viridis. The optimization of several steps in tissue culture allowed the rapid regeneration of plants and increased the rate of transformation up to 29%. This protocol could become a powerful tool for functional genomics in sugarcane.

  11. Field test of radioactive high efficiency filter and filter exchange techniques of fuel cycle examination facility

    International Nuclear Information System (INIS)

    Hwang, Yong Hwa; Lee, Hyung Kwon; Chun, Young Bum; Park, Dae Gyu; Ahn, Sang Bok; Chu, Yong Sun; Kim, Eun Ka.

    1997-12-01

    The development of high efficiency filter was started to protect human beings from the contamination of radioactive particles, toxic gases and bacillus, and its gradual performance increment led to the fabrication of Ultra Low Penetration Air Filter (ULPA) today. The application field of ULPA has been spread not only to the air conditioning of nuclear power facilities, semiconductor industries, life science, optics, medical care and general facilities but also to the core of ultra-precision facilities. Periodic performance test on the filters is essential to extend its life-time through effective maintenance. Especially, the bank test on HEPA filter of nuclear facilities handling radioactive materials is required for environmental safety. Nowadays, the bank test technology has been reached to the utilization of a minimized portable detecting instruments and the evaluation techniques can provide high confidence in the area of particle distribution and leakage test efficiency. (author). 16 refs., 13 tabs., 14 figs

  12. High-efficiency dielectric barrier Xe discharge lamp: theoretical and experimental investigations

    International Nuclear Information System (INIS)

    Beleznai, Sz; Mihajlik, G; Agod, A; Maros, I; Juhasz, R; Nemeth, Zs; Jakab, L; Richter, P

    2006-01-01

    A dielectric barrier Xe discharge lamp producing vacuum-ultraviolet radiation with high efficiency was investigated theoretically and experimentally. The cylindrical glass body of the lamp is equipped with thin strips of metal electrodes applied to diametrically opposite sides of the outer surface. We performed a simulation of discharge plasma properties based on one-dimensional fluid dynamics and also assessed the lamp characteristics experimentally. Simulation and experimental results are analysed and compared in terms of voltage and current characteristics, power input and discharge efficiency. Using the proposed lamp geometry and fast rise-time short square pulses of the driving voltage, an intrinsic discharge efficiency around 56% was predicted by simulation, and more than 60 lm W -1 lamp efficacy (for radiation converted into visible green light by phosphor coating) was demonstrated experimentally

  13. Fused Methoxynaphthyl Phenanthrimidazole Semiconductors as Functional Layer in High Efficient OLEDs.

    Science.gov (United States)

    Jayabharathi, Jayaraman; Ramanathan, Periyasamy; Karunakaran, Chockalingam; Thanikachalam, Venugopal

    2016-01-01

    Efficient hole transport materials based on novel fused methoxynaphthyl phenanthrimidazole core structure were synthesised and characterized. Their device performances in phosphorescent organic light emitting diodes were investigated. The high thermal stability in combination with the reversible oxidation process made promising candidates as hole-transporting materials for organic light-emitting devices. Highly efficient Alq3-based organic light emitting devices have been developed using phenanthrimidazoles as functional layers between NPB [4,4-bis(N-(1-naphthyl)-N-phenylamino)biphenyl] and Alq3 [tris(8-hydroxyquinoline)aluminium] layers. Using the device of ITO/NPB/4/Alq3/LiF/Al, a maximum luminous efficiency of 5.99 cd A(-1) was obtained with a maximum brightness of 40,623 cd m(-2) and a power efficiency of 5.25 lm W(-1).

  14. High-efficiency genome editing and allele replacement in prototrophic and wild strains of Saccharomyces.

    Science.gov (United States)

    Alexander, William G; Doering, Drew T; Hittinger, Chris Todd

    2014-11-01

    Current genome editing techniques available for Saccharomyces yeast species rely on auxotrophic markers, limiting their use in wild and industrial strains and species. Taking advantage of the ancient loss of thymidine kinase in the fungal kingdom, we have developed the herpes simplex virus thymidine kinase gene as a selectable and counterselectable marker that forms the core of novel genome engineering tools called the H: aploid E: ngineering and R: eplacement P: rotocol (HERP) cassettes. Here we show that these cassettes allow a researcher to rapidly generate heterogeneous populations of cells with thousands of independent chromosomal allele replacements using mixed PCR products. We further show that the high efficiency of this approach enables the simultaneous replacement of both alleles in diploid cells. Using these new techniques, many of the most powerful yeast genetic manipulation strategies are now available in wild, industrial, and other prototrophic strains from across the diverse Saccharomyces genus. Copyright © 2014 by the Genetics Society of America.

  15. Environmental friendly high efficient light source. Plasma lamp. 2006 annual report

    Energy Technology Data Exchange (ETDEWEB)

    Courret, G.

    2006-07-01

    This annual report for 2006 for the Swiss Federal Office of Energy (SFOE) reports on work being done on the development of a high-efficiency source of light based on the light emission of a plasma. The report presents a review of work done in 2006, including thermodynamics and assessment of the efficiency of the magnetron, tests with small bulbs, study of the standing wave ratio (microwave fluxes) and the development of a new coupling system to allow ignition in very small bulbs. Also, knowledge on the fillings of the bulb and induced effects of the modulator were gained. The development of a second generation of modulator to obtain higher efficiency at lower power is noted.

  16. High efficiency, monolithic fiber chirped pulse amplification system for high energy femtosecond pulse generation.

    Science.gov (United States)

    Peng, Xiang; Kim, Kyungbum; Mielke, Michael; Jennings, Stephen; Masor, Gordon; Stohl, Dave; Chavez-Pirson, Arturo; Nguyen, Dan T; Rhonehouse, Dan; Zong, Jie; Churin, Dmitriy; Peyghambarian, N

    2013-10-21

    A novel monolithic fiber-optic chirped pulse amplification (CPA) system for high energy, femtosecond pulse generation is proposed and experimentally demonstrated. By employing a high gain amplifier comprising merely 20 cm of high efficiency media (HEM) gain fiber, an optimal balance of output pulse energy, optical efficiency, and B-integral is achieved. The HEM amplifier is fabricated from erbium-doped phosphate glass fiber and yields gain of 1.443 dB/cm with slope efficiency >45%. We experimentally demonstrate near diffraction-limited beam quality and near transform-limited femtosecond pulse quality at 1.55 µm wavelength. With pulse energy >100 µJ and pulse duration of 636 fs (FWHM), the peak power is estimated to be ~160 MW. NAVAIR Public Release Distribution Statement A-"Approved for Public release; distribution is unlimited".

  17. Simulation design of P–I–N-type all-perovskite solar cells with high efficiency

    International Nuclear Information System (INIS)

    Du Hui-Jing; Wang Wei-Chao; Gu Yi-Fan

    2017-01-01

    According to the good charge transporting property of perovskite, we design and simulate a p–i–n-type all-perovskite solar cell by using one-dimensional device simulator. The perovskite charge transporting layers and the perovskite absorber constitute the all-perovskite cell. By modulating the cell parameters, such as layer thickness values, doping concentrations and energy bands of n-, i-, and p-type perovskite layers, the all-perovskite solar cell obtains a high power conversion efficiency of 25.84%. The band matched cell shows appreciably improved performance with widen absorption spectrum and lowered recombination rate, so weobtain a high J sc of 32.47 mA/cm 2 . The small series resistance of the all-perovskite solar cell also benefits the high J sc . The simulation provides a novel thought of designing perovskite solar cells with simple producing process, low production cost and high efficient structure to solve the energy problem. (paper)

  18. Test Program for High Efficiency Gas Turbine Exhaust Diffuser

    Energy Technology Data Exchange (ETDEWEB)

    Norris, Thomas R.

    2009-12-31

    This research relates to improving the efficiency of flow in a turbine exhaust, and thus, that of the turbine and power plant. The Phase I SBIR project demonstrated the technical viability of “strutlets” to control stalls on a model diffuser strut. Strutlets are a novel flow-improving vane concept intended to improve the efficiency of flow in turbine exhausts. Strutlets can help reduce turbine back pressure, and incrementally improve turbine efficiency, increase power, and reduce greenhouse gas emmission. The long-term goal is a 0.5 percent improvement of each item, averaged over the US gas turbine fleet. The strutlets were tested in a physical scale model of a gas turbine exhaust diffuser. The test flow passage is a straight, annular diffuser with three sets of struts. At the end of Phase 1, the ability of strutlets to keep flow attached to struts was demonstrated, but the strutlet drag was too high for a net efficiency advantage. An independently sponsored followup project did develop a highly-modified low-drag strutlet. In combination with other flow improving vanes, complicance to the stated goals was demonstrated for for simple cycle power plants, and to most of the goals for combined cycle power plants using this particular exhaust geometry. Importantly, low frequency diffuser noise was reduced by 5 dB or more, compared to the baseline. Appolicability to other diffuser geometries is yet to be demonstrated.

  19. High Efficiency Driving Electronics for General Illumination LED Luminaires

    Energy Technology Data Exchange (ETDEWEB)

    Upadhyay, Anand

    2012-10-31

    New generation of standalone LED driver platforms developed, which are more efficient These LED Drivers are more efficient (≥90%), smaller in size ( 0.15 in3/watt), lower in cost ( 12 cents/watt in high volumes in millions of units). And these products are very reliable having an operating life of over 50,000 hours. This technology will enable growth of LED light sources in the use. This will also help in energy saving and reducing total life cycle cost of LED units. Two topologies selected for next generation of LED drivers: 1) Value engineered single stage Flyback topology. This is suitable for low powered LED drivers up to 50W power. 2) Two stage boost power factor correction (PFC) plus LLC half bridge platform for higher powers. This topology is suitable for 40W to 300W LED drivers. Three new product platforms were developed to cover a wide range of LED drivers: 1) 120V 40W LED driver, 2) Intellivolt 75W LED driver, & 3) Intellivolt 150W LED driver. These are standalone LED drivers for rugged outdoor lighting applications. Based on these platforms number of products are developed and successfully introduced in the market place meeting key performance, size and cost goals.

  20. Metamaterial Receivers for High Efficiency Concentrated Solar Energy Conversion

    Energy Technology Data Exchange (ETDEWEB)

    Yellowhair, Julius E. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Concentrating Solar Technologies Dept.; Kwon, Hoyeong [Univ. of Texas, Austin, TX (United States). Dept. of Electrical and Computer Engineering; Alu, Andrea [Univ. of Texas, Austin, TX (United States). Dept. of Electrical and Computer Engineering; Jarecki, Robert L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Concentrating Solar Technologies Dept.; Shinde, Subhash L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Concentrating Solar Technologies Dept.

    2016-09-01

    Operation of concentrated solar power receivers at higher temperatures (>700°C) would enable supercritical carbon dioxide (sCO2) power cycles for improved power cycle efficiencies (>50%) and cost-effective solar thermal power. Unfortunately, radiative losses at higher temperatures in conventional receivers can negatively impact the system efficiency gains. One approach to improve receiver thermal efficiency is to utilize selective coatings that enhance absorption across the visible solar spectrum while minimizing emission in the infrared to reduce radiative losses. Existing coatings, however, tend to degrade rapidly at elevated temperatures. In this report, we report on the initial designs and fabrication of spectrally selective metamaterial-based absorbers for high-temperature, high-thermal flux environments important for solarized sCO2 power cycles. Metamaterials are structured media whose optical properties are determined by sub-wavelength structural features instead of bulk material properties, providing unique solutions by decoupling the optical absorption spectrum from thermal stability requirements. The key enabling innovative concept proposed is the use of structured surfaces with spectral responses that can be tailored to optimize the absorption and retention of solar energy for a given temperature range. In this initial study through the Academic Alliance partnership with University of Texas at Austin, we use Tungsten for its stability in expected harsh environments, compatibility with microfabrication techniques, and required optical performance. Our goal is to tailor the optical properties for high (near unity) absorptivity across the majority of the solar spectrum and over a broad range of incidence angles, and at the same time achieve negligible absorptivity in the near infrared to optimize the energy absorbed and retained. To this goal, we apply the recently developed concept of plasmonic Brewster angle to suitably designed

  1. Highly efficient white organic light-emitting devices consisting of undoped ultrathin yellow phosphorescent layer

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Shengqiang [State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Information, University of Electronic Science and Technology of China (UESTC), Chengdu 610054 (China); Yu, Junsheng, E-mail: jsyu@uestc.edu.cn [State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Information, University of Electronic Science and Technology of China (UESTC), Chengdu 610054 (China); Ma, Zhu; Zhao, Juan [State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Information, University of Electronic Science and Technology of China (UESTC), Chengdu 610054 (China)

    2013-02-15

    High-efficiency white organic light-emitting devices (WOLEDs) based on an undoped ultrathin yellow light-emitting layer and a doped blue light-emitting layer were demonstrated. While the thickness of blue light-emitting layer, formed by doping a charge-trapping phosphor, iridium(III) bis(4 Prime ,6 Prime -difluorophenylpyridinato)tetrakis(1-pyrazolyl)borate (FIr6) in a wide bandgap host, was kept constant, the thickness of neat yellow emissive layer of novel phosphorescent material, bis[2-(4-tertbutylphenyl)benzothiazolato-N,C{sup 2 Prime }]iridium (acetylacetonate) [(t-bt){sub 2}Ir(acac)] was varied to optimize the device performance. The optimized device exhibited maximum luminance, current efficiency and power efficiency of 24,000 cd/m{sup 2} (at 15.2 V), 79.0 cd/A (at 1550 cd/m{sup 2}) and 40.5 lm/W (at 1000 cd/m{sup 2}), respectively. Besides, the white-light emission covered a wide range of visible spectrum, and the Commission Internationale de l'Eclairage coordinates were (0.32, 0.38) with a color temperature of 5800 K at 8 V. Moreover, high external quantum efficiency was also obtained in the high-efficiency WOLEDs. The performance enhancement was attributed to the proper thickness of (t-bt){sub 2}Ir(acac) layer that enabled adequate current density and enough phosphorescent dye to trap electrons. - Highlights: Black-Right-Pointing-Pointer Highly efficient WOLEDs based on two complementary layers were fabricated. Black-Right-Pointing-Pointer The yellow emissive layer was formed by utilizing undoping system. Black-Right-Pointing-Pointer The blue emissive layer was made by host-guest doping system. Black-Right-Pointing-Pointer The thickness of the yellow emissive layer was varied to make device optimization. Black-Right-Pointing-Pointer The optimized device achieved high power efficiency of 40.5 lm/W.

  2. Gallium nitride based transistors for high-efficiency microwave switch-mode amplifiers

    Energy Technology Data Exchange (ETDEWEB)

    Maroldt, Stephan

    2012-07-01

    Highly-efficient switch-mode power amplifiers form key elements in future fully-digital base stations for mobile communication. This novel digital base station concept reduces system energy consumption, complexity, size and costs, while the flexibility in terms of multi-band operation and signal modulation improves. In this work, innovative core circuits for digital high-efficiency class-D and class-S power amplifiers based on gallium nitride (GaN) technology were developed for the application in digital base stations. A combination of optimized GaN devices and improvements in circuit design allow a highly-efficient switch-mode operation at mobile communication frequencies between 0.45 GHz and 2 GHz. Transistor device modeling for switch-mode operation, the simulation environment, and a broadband measurement system were established for the design and evaluation of digital switchmode power amplifiers. The design of broadband core circuits for switch-mode amplifier concepts was analyzed for dual-stage amplifier circuits, using an initial GaN technology with a gate length of 0.25 {mu}m. A speed-enhanced driver stage improved the circuit switching speed sufficiently above 1 GHz. Speed and efficiency of the amplifier core circuits were studied related to transistor parameters like cut-off frequency or gate capacitance. A reduced gate length was found to improve the switching speed, while a lower on-resistance allows the reduction of the inherent static losses of the GaN-based switches. Apart from this, the restriction of a 50 Ohm environment was found to be a major output power and switching speed limitation, due to a poor switching drive capability of the input capacitance of the GaN circuit. Finally, the optimized transistor and circuit design with an output gate width of 1.2 mm were effectively implemented in the given environment for an operation up to 2 GHz with a high drain efficiency of >65% and a digital output power of 5 W. A maximum output power of 9.7 W and a

  3. High efficiency solid-state sensitized heterojunction photovoltaic device

    KAUST Repository

    Wang, Mingkui

    2010-06-01

    The high molar extinction coefficient heteroleptic ruthenium dye, NaRu(4,4′-bis(5-(hexylthio)thiophen-2-yl)-2,2′-bipyridine) (4-carboxylic acid-4′-carboxylate-2,2′-bipyridine) (NCS) 2, exhibits certified 5% electric power conversion efficiency at AM 1.5 solar irradiation (100 mW cm-2) in a solid-state dye-sensitized solar cell using 2,2′,7,7′-tetrakis-(N,N-di-pmethoxyphenylamine)-9, 9′-spirobifluorene (spiro-MeOTAD) as the organic hole-transporting material. This demonstration elucidates a class of photovoltaic devices with potential for low-cost power generation. © 2010 Elsevier Ltd. All rights reserved.

  4. High efficiency semimetal/semiconductor nanocomposite thermoelectric materials

    International Nuclear Information System (INIS)

    Zide, J. M. O.; Bahk, J.-H.; Zeng, G.; Bowers, J. E.; Singh, R.; Zebarjadi, M.; Bian, Z. X.; Shakouri, A.; Lu, H.; Gossard, A. C.; Feser, J. P.; Xu, D.; Singer, S. L.; Majumdar, A.

    2010-01-01

    Rare-earth impurities in III-V semiconductors are known to self-assemble into semimetallic nanoparticles which have been shown to reduce lattice thermal conductivity without harming electronic properties. Here, we show that adjusting the band alignment between ErAs and In 0.53 Ga 0.47-X Al X As allows energy-dependent scattering of carriers that can be used to increase thermoelectric power factor. Films of various Al concentrations were grown by molecular beam epitaxy, and thermoelectric properties were characterized. We observe concurrent increases in electrical conductivity and Seebeck coefficient with increasing temperatures, demonstrating energy-dependent scattering. We report the first simultaneous power factor enhancement and thermal conductivity reduction in a nanoparticle-based system, resulting in a high figure of merit, ZT=1.33 at 800 K.

  5. High efficiency solid-state sensitized heterojunction photovoltaic device

    KAUST Repository

    Wang, Mingkui; Liu, Jingyuan; Cevey-Ha, Ngoc-Le; Moon, Soo-Jin; Liska, Paul; Humphry-Baker, Robin; Moser, Jacques-E.; Grä tzel, Carole; Wang, Peng; Zakeeruddin, Shaik M.

    2010-01-01

    The high molar extinction coefficient heteroleptic ruthenium dye, NaRu(4,4′-bis(5-(hexylthio)thiophen-2-yl)-2,2′-bipyridine) (4-carboxylic acid-4′-carboxylate-2,2′-bipyridine) (NCS) 2, exhibits certified 5% electric power conversion efficiency at AM 1.5 solar irradiation (100 mW cm-2) in a solid-state dye-sensitized solar cell using 2,2′,7,7′-tetrakis-(N,N-di-pmethoxyphenylamine)-9, 9′-spirobifluorene (spiro-MeOTAD) as the organic hole-transporting material. This demonstration elucidates a class of photovoltaic devices with potential for low-cost power generation. © 2010 Elsevier Ltd. All rights reserved.

  6. Highly efficient perovskite solar cells with crosslinked PCBM interlayers

    KAUST Repository

    Qiu, W.

    2017-01-09

    Commercially available phenyl-C-butyric acid methyl ester (PCBM) is crosslinked with 1,6-diazidohexane (DAZH), resulting in films resistant to common solvents used in perovskite solar cell processing. By using crosslinked PCBM as an interlayer and (HC(NH))(CHNH)PbIBr as the active layer, we achieve small area devices and modules with a maximum steady-state power conversion efficiency of 18.1% and 14.9%, respectively.

  7. Initial Test Bed for Very High Efficiency Solar Cells

    Science.gov (United States)

    2008-05-01

    efficiency, both at the solar cell and module levels. The optical system consists of a tiled nonimaging concentrating system, coupled with a spectral...To achieve the benefits of the new photovoltaic system architecture, a new optical element is designed that combines a nonimaging optical...of the power from each solar cell. Optics Design The most advanced optical design is based on non- symmetric, nonimaging optics, tiled into an

  8. EVALUATION OF A LOW FRICTION - HIGH EFFICIENCY ROLLER BEARING ENGINE

    Energy Technology Data Exchange (ETDEWEB)

    Kolarik, Robert V. II; Shattuck, Charles W.; Copper, Anthony P.

    2009-06-30

    This Low Friction (High Efficiency Roller Bearing) Engine (LFE) report presents the work done by The Timken Company to conduct a technology demonstration of the benefits of replacing hydrodynamic bearings with roller bearings in the crankshaft and camshaft assemblies of an internal combustion engine for the purpose of collecting data sufficient to prove merit. The engines in the present study have been more extensively converted to roller bearings than any previous studies (40 needle roller bearings per engine) to gain understanding of the full potential of application of bearing technology. The project plan called for comparative testing of a production vehicle which was already respected for having demonstrated low engine friction levels with a rollerized version of that engine. Testing was to include industry standard tests for friction, emissions and fuel efficiency conducted on instrumented dynamometers. Additional tests for fuel efficiency, cold start resistance and other measures of performance were to be made in the actual vehicle. Comparative measurements of noise, vibration and harshness (NVH), were planned, although any work to mitigate the suspected higher NVH level in the rollerized engine was beyond the scope of this project. Timken selected the Toyota Avalon with a 3.5L V-6 engine as the test vehicle. In an attempt to minimize cost and fabrication time, a ‘made-from’ approach was proposed in which as many parts as possible would be used or modified from production parts to create the rollerized engine. Timken commissioned its test partner, FEV Engine Technology, to do a feasibility study in which they confirmed that using such an approach was possible to meet the required dimensional restrictions and tolerances. In designing the roller bearing systems for the crank and cam trains, Timken utilized as many production engine parts as possible. The crankshafts were produced from production line forgings, which use Timken steel, modified with special

  9. High-efficient Nd:YAG microchip laser for optical surface scanning

    Science.gov (United States)

    Šulc, Jan; Jelínková, Helena; Nejezchleb, Karel; Škoda, Václav

    2017-12-01

    A CW operating, compact, high-power, high-efficient diode pumped 1064nm laser, based on Nd:YAG active medium, was developed for optical surface scanning and mapping applications. To enhance the output beam quality, laser stability, and compactness, a microchip configuration was used. In this arrangement the resonator mirrors were deposited directly on to the laser crystal faces. The Nd-doping concentration was 1 at.% Nd/Y. The Nd:YAG crystal was 5mm long. The laser resonator without pumping radiation recuperation was investigated {the output coupler was transparent for pumping radiation. For the generated laser radiation the output coupler reflectivity was 95%@1064 nm. The diameter of the samples was 5 mm. For the laser pumping two arrangements were investigated. Firstly, a fibre coupled laser diode operating at wavelength 808nm was used in CW mode. The 400 ¹m fiber was delivering up to 14W of pump power amplitude to the microchip laser. The maximum CW output power of 7.2W @ 1064nm in close to TEM00 beam was obtained for incident pumping power 13.7W @ 808 nm. The differential efficiency in respect to the incident pump power reached 56 %. Secondly, a single-emitter, 1W laser diode operating at 808nm was used for Nd:YAG microchip pumping. The laser pumping was directly coupled into the microchip laser using free-space lens optics. Slope efficiency up to 70% was obtained in stable, high-quality, 1064nm laser beam with CW power up to 350mW. The system was successfully used for scanning of super-Gaussian laser mirrors reflectivity profile.

  10. Report on results of feasibility study in fiscal 1986 on use of coal in next generation high efficiency power generation system - research commissioned by Moonlight project propulsion room of Agency of Industrial Science and Technology. MHD generation subcommittee; 1986 nendo jisedai kokoritsu hatsuden system no sekitan gas riyo feasibility chosa kenkyu seika hokokusho (Kogyo Gijutsuin Moonlight keikaku suishinshitsu itaku chosa). MHD hatsuden bunkakai

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1987-03-01

    A research study was done on MHD generation by coal gasificating combustion. MHD generation is a very attractive power generation system such that efficiency is as high as 55%, that preservation of the environment is superior, and that coal can be used as fuel. The open cycle seems suitable for a one million kW class as a base load following up load fluctuation of approximately 20%, while the closed cycle for 200-300 thousand kW class doing daily start-stop. With a mind to a scale of 30 MWt, in the open cycle, R and D is required in such items as a coal gas combustor, generation channel, high temperature air heater, and seed/slag recovery device. In the closed cycle, R and D is required in the generation channel, high temperature helium heater/high temperature valve, seed injection/recovery device, operation technique of helium closed loop, etc.. Moreover, as a total system, development is necessary in the areas of conceptual design and optimization method, partial load operation and DSS operation method, for example. (NEDO)

  11. Fiscal 1993 report on technological results. R and D on new forming technology of composite materials (Development of innovative technology for producing members for high efficiency power generation); 1993 nendo fukugo zairyo shinseikei gijutsu no kenkyu kaihatsu seika hokokusho. Kokoritsu hatsuden'yo buzai sosei gijutsu kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-03-01

    A forming technology was developed which uses superplasticity of composite materials, i.e., high-functional materials for power generating equipment for example. Activities were conducted in the three areas of (1) ceramic based composite materials, (2) development of metal-based composite forming technology, and (3) comprehensive investigation and adjustment. In (1), with a view to finding a composite forming technology, in which high tenacity materials are obtained by evenly dispersing particles or whiskers as reinforcements in a matrix, a room temperature forming technique using fine particles was exploited, as were a high temperature forming technique using fused bodies and a possibility of manifestation of superplasticity in the prepared composite materials. The materials used were Si{sub 3}N{sub 4} matrix-SiC, Al{sub 2}O{sub 3} matrix-TiC, and glass matrix composite based materials filling ceramics in fine holes of porous glass. In (2), composite forming technologies were examined for such composite materials as Al alloy matrix-SiC particulate-based by a molten metal stirring method, Al alloy matrix-ceramics short fiber-based by a high pressure forging method, Ti alloy matrix-ceramics particulate-based by a mechanical alloying method, and Al alloy matrix-ceramics particulate-based by an alkoxide method/powder metallurgy method. (NEDO)

  12. Completion of high-efficiency BWR turbine plant 'Hamaoka unit No. 4'

    International Nuclear Information System (INIS)

    Tsuji, Kunio; Hamaura, Norikazu; Shibashita, Naoaki; Kazama, Seiichi

    1995-01-01

    Accompanying the increase of capacity of nuclear power plants in Japan, the plants having heightened economical efficiency, which are supported by the improvement of thermal efficiency and the reduction of dose, are demanded. Hitachi Ltd. has completed No. 4 turbine unit of 1137 MW output in Hamaoka Nuclear Power Station, Chubu Electric Power Co., Inc., which is the largest capacity machine in Japanese BWR plants. In this unit, the moisture separator heater, the steam turbine with high efficiency, and the hollow thread film condensate filter which treats the total flow rate of condensate are used as the reheating type BWR plant for the first time in Japan, and the plan of heightened economy and operation was adopted. It was confirmed by the trial for about 10 months that the planned performance was sufficiently satisfied, and the commercial operation was started in September, 1993. The features of the 1137 MW turbine unit are explained. The turbine is of tandem six-flow exhaust condensation type. Diffuser type low pressure turbine exhaust chambers, butterfly type combination intermediate valve are adopted. The stages with the blades having moisture-separating grooves were corrected. The reliability of the shaft system was improved. The adoption of the moisture separator heater and the application of the hollow thread film type condensate filter are explained. (K.I.)

  13. Corrugation Architecture Enabled Ultraflexible Wafer-Scale High-Efficiency Monocrystalline Silicon Solar Cell

    KAUST Repository

    Bahabry, Rabab R.

    2018-01-02

    Advanced classes of modern application require new generation of versatile solar cells showcasing extreme mechanical resilience, large-scale, low cost, and excellent power conversion efficiency. Conventional crystalline silicon-based solar cells offer one of the most highly efficient power sources, but a key challenge remains to attain mechanical resilience while preserving electrical performance. A complementary metal oxide semiconductor-based integration strategy where corrugation architecture enables ultraflexible and low-cost solar cell modules from bulk monocrystalline large-scale (127 × 127 cm) silicon solar wafers with a 17% power conversion efficiency. This periodic corrugated array benefits from an interchangeable solar cell segmentation scheme which preserves the active silicon thickness of 240 μm and achieves flexibility via interdigitated back contacts. These cells can reversibly withstand high mechanical stress and can be deformed to zigzag and bifacial modules. These corrugation silicon-based solar cells offer ultraflexibility with high stability over 1000 bending cycles including convex and concave bending to broaden the application spectrum. Finally, the smallest bending radius of curvature lower than 140 μm of the back contacts is shown that carries the solar cells segments.

  14. Corrugation Architecture Enabled Ultraflexible Wafer-Scale High-Efficiency Monocrystalline Silicon Solar Cell

    KAUST Repository

    Bahabry, Rabab R.; Kutbee, Arwa T.; Khan, Sherjeel M.; Sepulveda, Adrian C.; Wicaksono, Irmandy; Nour, Maha A.; Wehbe, Nimer; Almislem, Amani Saleh Saad; Ghoneim, Mohamed T.; Sevilla, Galo T.; Syed, Ahad; Shaikh, Sohail F.; Hussain, Muhammad Mustafa

    2018-01-01

    Advanced classes of modern application require new generation of versatile solar cells showcasing extreme mechanical resilience, large-scale, low cost, and excellent power conversion efficiency. Conventional crystalline silicon-based solar cells offer one of the most highly efficient power sources, but a key challenge remains to attain mechanical resilience while preserving electrical performance. A complementary metal oxide semiconductor-based integration strategy where corrugation architecture enables ultraflexible and low-cost solar cell modules from bulk monocrystalline large-scale (127 × 127 cm) silicon solar wafers with a 17% power conversion efficiency. This periodic corrugated array benefits from an interchangeable solar cell segmentation scheme which preserves the active silicon thickness of 240 μm and achieves flexibility via interdigitated back contacts. These cells can reversibly withstand high mechanical stress and can be deformed to zigzag and bifacial modules. These corrugation silicon-based solar cells offer ultraflexibility with high stability over 1000 bending cycles including convex and concave bending to broaden the application spectrum. Finally, the smallest bending radius of curvature lower than 140 μm of the back contacts is shown that carries the solar cells segments.

  15. Next generation of high-efficient waste incinerators. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Jappe Frandsen, F.

    2010-11-15

    Modern society produces increasing amounts of combustible waste which may be utilized for heat and power production, at a lower emission of CO{sub 2}, e.g. by substituting a certain fraction of energy from fossil fuel-fired power stations. In 2007, 20.4 % of the district heating and 4.5 % of the power produced in Denmark came from thermal conversion of waste, and waste is a very important part of a future sustainable, and independent, Danish energy supply [Frandsen et al., 2009; Groen Energi, 2010]. In Denmark, approx 3.3 Mtons of waste was produced in 2005, an amount predicted to increase to 4.4 Mtons by the year 2030. According to Affald Danmark, 25 % of the current WtE plant capacity in Denmark is older than 20 years, which is usually considered as the technical and economical lifetime of WtE plants. Thus, there is a need for installation of a significant fraction of new waste incineration capacity, preferentially with an increased electrical efficiency, within the next few years. Compared to fossil fuels, waste is difficult to handle in terms of pre-treatment, combustion, and generation of reusable solid residues. In particular, the content of inorganic species (S, Cl, K, Na, etc.) is problematic, due to enhanced deposition and corrosion - especially at higher temperatures. This puts severe constraints on the electrical efficiency of grate-fired units utilizing waste, which seldom exceeds 26-27%, campared to 46-48 % for coal combustion in suspension. The key parameters when targeting higher electrical efficiency are the pressure and temperature in the steam cycle, which are limited by high-temperature corrosion, boiler- and combustion-technology. This report reviews some of the means that can be applied in order to increase the electrical efficiency in plants firing waste on a grate. (Author)

  16. High efficiency Dual-Cycle Conversion System using Kr-85.

    Science.gov (United States)

    Prelas, Mark A; Tchouaso, Modeste Tchakoua

    2018-04-26

    This paper discusses the use of one of the safest isotopes known isotopes, Kr-85, as a candidate fuel source for deep space missions. This isotope comes from 0.286% of fission events. There is a vast quantity of Kr-85 stored in spent fuel and it is continually being produced by nuclear reactors. In using Kr-85 with a novel Dual Cycle Conversion System (DCCS) it is feasible to boost the system efficiency from 26% to 45% over a single cycle device while only increasing the system mass by less than 1%. The Kr-85 isotope is the ideal fuel for a Photon Intermediate Direct Energy Conversion (PIDEC) system. PIDEC is an excellent choice for the top cycle in a DCCS. In the top cycle, ionization and excitation of the Kr-85:Cl gas mixture (99% Kr and 1% Cl) from beta particles creates KrCl* excimer photons which are efficiently absorbed by diamond photovoltaic cells on the walls of the pressure vessels. The benefit of using the DCCS is that Kr-85 is capable of operating at high temperatures in the primary cycle and the residual heat can then be converted into electrical power in the bottom cycle which uses a Stirling Engine. The design of the DCCS begins with a spherical pressure vessel of radius 13.7 cm with 3.7 cm thick walls and is filled with a Kr-85:Cl gas mixture. The inner wall has diamond photovoltaic cells attached to it and there is a sapphire window between the diamond photovoltaic cells and the Kr-85:Cl gas mixture which shields the photovoltaic cells from beta particles. The DCCS without a gamma ray shield has specific power of 6.49 W/kg. A removable 6 cm thick tungsten shield is used to safely limit the radiation exposure levels of personnel. A shadow shield remains in the payload to protect the radiation sensitive components in the flight package. The estimated specific power of the unoptimized system design in this paper is about 2.33 W/kg. The specific power of an optimized system should be higher. The Kr-85 isotope is relatively safe because it

  17. High efficiency motors - performance, economy and reliability, by optimisation

    Energy Technology Data Exchange (ETDEWEB)

    Caselotti, P.; Conchetto, A.; Tavner, P.J.

    2000-07-01

    The challenge of the efficiency initiatives in North America and the European Union is to improve performance without reducing power-weight by adding materials and increasing cost. This has been the subject of other papers, Haataja et al Ref2, where the key area has been identified as reducing loss. This paper suggests that addressing the fundamental problem of heat transfer in the TEFC machine, in addition to reducing loss will make it possible to improve performance and still provide competitive products. (orig.)

  18. High Efficiency Polymer Solar Cells with Long Operating Lifetimes

    KAUST Repository

    Peters, Craig H.; Sachs-Quintana, I. T.; Kastrop, John P.; Beaupré , Serge; Leclerc, Mario; McGehee, Michael D.

    2011-01-01

    Organic bulk-heterojunction solar cells comprising poly[N-9'-hepta-decanyl- 2,7-carbazole-alt-5,5-(4',7'-di-2-thienyl-2', 1',3'-benzothiadiazole) (PCDTBT) are systematically aged and demonstrate lifetimes approaching seven years, which is the longest reported lifetime for polymer solar cells. An experimental set-up is described that is capable of testing large numbers of solar cells, holding each device at its maximum power point while controlling and monitoring the temperature and light intensity. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. High Efficiency Polymer Solar Cells with Long Operating Lifetimes

    KAUST Repository

    Peters, Craig H.

    2011-04-20

    Organic bulk-heterojunction solar cells comprising poly[N-9\\'-hepta-decanyl- 2,7-carbazole-alt-5,5-(4\\',7\\'-di-2-thienyl-2\\', 1\\',3\\'-benzothiadiazole) (PCDTBT) are systematically aged and demonstrate lifetimes approaching seven years, which is the longest reported lifetime for polymer solar cells. An experimental set-up is described that is capable of testing large numbers of solar cells, holding each device at its maximum power point while controlling and monitoring the temperature and light intensity. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Technical basis for the proposed high efficiency nuclear fuel program

    International Nuclear Information System (INIS)

    MacDonald, P.E.; Herring, J.S.; Crawford, D.C.; Neimark, L.E.

    1999-01-01

    Greenhouse gas emissions from fossil fired electricity generating stations will dramatically increase over the next 20 years. Nuclear energy is the only fully developed technology able to supply large amounts of electricity without generation of greenhouse gases. However, the problem of noncompetitive economics and public concerns about radioactive waste disposal, safety, and nuclear weapons proliferation may prevent the reemergence of nuclear power as a preferred option for new electric energy generation in the U.S. This paper discusses a new research program to help address these issues, by developing fuel designs capable of burnup values in excess of 60 MWD/kgU. The objectives of the program are to: improve the reliability and robustness of light water reactor fuel, thereby improving safety margins; Significantly increase the energy generated by each fuel loading, thereby achieving longer operating cycles, higher capacity factors, and lower cost electric power; Significantly reduce the volume of spent nuclear fuel discharged for disposal by allowing more energy to be extracted from each fuel element prior to discharge; Develop fuel that is much more proliferation resistant. (author)

  1. High-efficiency VCSEL arrays for illumination and sensing in consumer applications

    Science.gov (United States)

    Seurin, Jean-Francois; Zhou, Delai; Xu, Guoyang; Miglo, Alexander; Li, Daizong; Chen, Tong; Guo, Baiming; Ghosh, Chuni

    2016-03-01

    There has been increased interest in vertical-cavity surface-emitting lasers (VCSELs) for illumination and sensing in the consumer market, especially for 3D sensing ("gesture recognition") and 3D image capture. For these applications, the typical wavelength range of interest is 830~950nm and power levels vary from a few milli-Watts to several Watts. The devices are operated in short pulse mode (a few nano-seconds) with fast rise and fall times for time-of-flight applications (ToF), or in CW/quasi-CW for structured light applications. In VCSELs, the narrow spectrum and its low temperature dependence allows the use of narrower filters and therefore better signal-to-noise performance, especially for outdoor applications. In portable devices (mobile devices, wearable devices, laptops etc.) the size of the illumination module (VCSEL and optics) is a primary consideration. VCSELs offer a unique benefit compared to other laser sources in that they are "surface-mountable" and can be easily integrated along with other electronics components on a printed circuit board (PCB). A critical concern is the power-conversion efficiency (PCE) of the illumination source operating at high temperatures (>50 deg C). We report on various VCSEL based devices and diffuser-integrated modules with high efficiency at high temperatures. Over 40% PCE was achieved in broad temperature range of 0-70 °C for either low power single devices or high power VCSEL arrays, with sub- nano-second rise and fall time. These high power VCSEL arrays show excellent reliability, with extracted mean-time-to-failure (MTTF) of over 500 years at 60 °C ambient temperature and 8W peak output.

  2. Molecular design toward highly efficient photovoltaic polymers based on two-dimensional conjugated benzodithiophene.

    Science.gov (United States)

    Ye, Long; Zhang, Shaoqing; Huo, Lijun; Zhang, Maojie; Hou, Jianhui

    2014-05-20

    As researchers continue to develop new organic materials for solar cells, benzo[1,2-b:4,5-b']dithiophene (BDT)-based polymers have come to the fore. To improve the photovoltaic properties of BDT-based polymers, researchers have developed and applied various strategies leading to the successful molecular design of highly efficient photovoltaic polymers. Novel polymer materials composed of two-dimensional conjugated BDT (2D-conjugated BDT) have boosted the power conversion efficiency of polymer solar cells (PSCs) to levels that exceed 9%. In this Account, we summarize recent progress related to the design and synthesis of 2D-conjugated BDT-based polymers and discuss their applications in highly efficient photovoltaic devices. We introduce the basic considerations for the construction of 2D-conjugated BDT-based polymers and systematic molecular design guidelines. For example, simply modifying an alkoxyl-substituted BDT to form an alkylthienyl-substituted BDT can improve the polymer hole mobilities substantially with little effect on their molecular energy level. Secondly, the addition of a variety of chemical moieties to the polymer can produce a 2D-conjugated BDT unit with more functions. For example, the introduction of a conjugated side chain with electron deficient groups (such as para-alkyl-phenyl, meta-alkoxyl-phenyl, and 2-alkyl-3-fluoro-thienyl) allowed us to modulate the molecular energy levels of 2D-conjugated BDT-based polymers. Through the rational design of BDT analogues such as dithienobenzodithiophene (DTBDT) or the insertion of larger π bridges, we can tune the backbone conformations of these polymers and modulate their photovoltaic properties. We also discuss the influence of 2D-conjugated BDT on polymer morphology and the blends of these polymers with phenyl-C61 (or C71)-butyric acid methyl ester (PCBM). Finally, we summarize the various applications of the 2D-conjugated BDT-based polymers in highly efficient PSC devices. Overall, this Account

  3. High efficiency filtration of liquid-metal-generated aerosols

    International Nuclear Information System (INIS)

    First, M.W.

    1977-01-01

    This paper will present data on filter performance for the range of sodium-containing aerorols that can result from large and small releases of hot metallic sodium into confined spaces containing air or special atmospheres and will compare the particle collection effectiveness, space and power requirements, service life, and disposal of the collected materials for the several options. Prompt reduction of in-vessel aerosols with methods that induce rapid coagulation and sedimentation by the application of violent turbulance, sonic energy, or electrostatic attraction; by aerosol scavenging with massive inert dust additions; and by a number of other innovative methods is of special interest because of their potential ability to bring down the aerosol cloud very rapidly and thereby to reduce vessel out-leakage drastically; as well as to relieve the particle load on filters. These methods will be examined as supplements to filtration methods for control of sodium-containing aerosols

  4. High efficient vacuum arc plant for coating deposition

    International Nuclear Information System (INIS)

    Aksenov, I.I.; Belous, V.A.

    2008-01-01

    A number of progressive technical solutions are used in the 'Bulat-9' machine designed for vacuum arc coating deposition. The features of the machine are: a dome shaped working chamber that allows to 'wash' its inner surfaces with hot nitrogen or argon gas; a system of automatic loading/unloading of articles to be treated into the chamber through its bottom; shielding of the inner surfaces of the chamber by heated panels; improved vacuum arc plasma sources including filtered one; four ported power supply for the vacuum arc discharges; LC oscillatory circuits suppressing microarcs on the substrate; the system of automatic control of a working process. The said technical features cause the apparatus originality and novelty preserved up to-day

  5. High efficiency polymer solar cells with vertically modulated nanoscale morphology

    International Nuclear Information System (INIS)

    Kumar, Ankit; Hong Ziruo; Yang Yang; Li Gang

    2009-01-01

    Nanoscale morphology has been shown to be a critical parameter governing charge transport properties of polymer bulk heterojunction (BHJ) solar cells. Recent results on vertical phase separation have intensified the research on 3D morphology control. In this paper, we intend to modify the distribution of donors and acceptors in a classical BHJ polymer solar cell by making the active layer richer in donors and acceptors near the anode and cathode respectively. Here, we chose [6,6]-phenyl- C 61 -butyric acid methyl ester (PCBM) to be the acceptor material to be thermally deposited on top of [poly(3-hexylthiophene)] P3HT: the PCBM active layer to achieve a vertical composition gradient in the BHJ structure. Here we report on a solar cell with enhanced power conversion efficiency of 4.5% which can be directly correlated with the decrease in series resistance of the device.

  6. The development and chemistry of high efficiency combined cycle plants

    International Nuclear Information System (INIS)

    Svoboda, Robert

    1999-01-01

    This paper presents a boiler concept based on the combination of a low-pressure drum-type boiler with high-pressure once-through boiler and the appropriate water/steam cycle. An all volatile treatment is used in the low-pressure boiler and oxygenated treatment for the once-through high pressure system. Impurity control is achieved by adapted system design and materials, high quality make-up, an appropriate cleanliness concept and clean-up procedures for a cold start. Cycle refreshing is realized by blowdown from the high-pressure water-separator. This concept utilizes simper and less equipment than traditional solutions, resulting in increased power plant reliability and less requirement on maintenance and on capital cost [it

  7. Simple Motor Control Concept Results High Efficiency at High Velocities

    Science.gov (United States)

    Starin, Scott; Engel, Chris

    2013-09-01

    The need for high velocity motors in space applications for reaction wheels and detectors has stressed the limits of Brushless Permanent Magnet Motors (BPMM). Due to inherent hysteresis core losses, conventional BPMMs try to balance the need for torque verses hysteresis losses. Cong-less motors have significantly less hysteresis losses but suffer from lower efficiencies. Additionally, the inherent low inductance in cog-less motors result in high ripple currents or high switching frequencies, which lowers overall efficiency and increases performance demands on the control electronics.However, using a somewhat forgotten but fully qualified technology of Isotropic Magnet Motors (IMM), extremely high velocities may be achieved at low power input using conventional drive electronics. This paper will discuss the trade study efforts and empirical test data on a 34,000 RPM IMM.

  8. Highly Efficient Segmented p-type Thermoelectric Leg

    Science.gov (United States)

    Sadia, Yatir; Ben-Yehuda, Ohad; Gelbstein, Yaniv

    In the past years, energy demands in the entire world have been constantly increasing. This fact, coupled with the requirement for decreasing the world's dependence on fossil fuels, has given rise to the need for alternative energy sources. While no single alternative energy source can solely replace the traditional fossil fuels, the combination of several alternative power sources can greatly decrease their usage. Thermoelectricity is one way to produce such energy via the harvesting of waste heat into electricity. One common example is the automobile industry which in the past few years had been looking into the option of harvesting the waste heat created by the engine, around the exhaust pipe and in the catalytic converter. Thermoelectricity is ideal for such application since it can convert the energy directly into electric current without any moving parts, thereby extending the life cycle of the operation.

  9. Advances in a high efficiency commercial pulse tube cooler

    Science.gov (United States)

    Zhang, Yibing; Li, Haibing; Wang, Xiaotao; Dai, Wei; Yang, Zhaohui; Luo, Ercang

    2017-12-01

    The pulse tube cryocooler has the advantage of no moving part at the cold end and offers a high reliability. To further extend its use in commercial applications, efforts are still needed to improve efficiency, reliability and cost effectiveness. This paper generalizes several key innovations in our newest cooler. The cooler consists of a moving magnet compressor with dual-opposed pistons, and a co-axial cold finger. Ambient displacers are employed to recover the expansion work to increase cooling efficiency. Inside the cold finger, the conventional flow straightener screens are replaced by a tapered throat between the cold heat exchanger and the pulse tube to strengthen its immunity to the working gas contamination as well as to simplify the manufacturing processes. The cold heat exchanger is made by copper forging process which further reduces the cost. Inside the compressor, a new gas bearing design has brought in assembling simplicity and running reliability. Besides the cooler itself, electronic controller is also important for actual application. A dual channel and dual driving mode control mechanism has been selected, which reduces the vibration to a minimum, meanwhile the cool-down speed becomes faster and run-time efficiency is higher. With these innovations, the cooler TC4189 reached a no-load temperature of 44 K and provided 15 W cooling power at 80K, with an input electric power of 244 W and a cooling water temperature of 23 ℃. The efficiency reached 16.9% of Carnot at 80 K. The whole system has a total mass of 4.3 kg.

  10. High-efficiency SO2 removal in utility FGD systems

    International Nuclear Information System (INIS)

    Phillips, J.L.; Gray, S.; Dekraker, D.

    1995-01-01

    The U.S. Department of Energy (DOE) and the Electric Power Research Institute (EPRI) have contracted with Radian Corporation to conduct full-scale testing, process modeling, and economic evaluations of six existing utility flue gas desulfurization (FGD) systems. The project objective is to evaluate low capital cost upgrades for achieving up to 98% sulfur dioxide (SO 2 ) removal efficiency in a variety of FGD system types. The systems include dual-loop, packed absorbers at Tampa Electric Company's Big Bend Station; cocurrent, packed absorbers at Hoosier Energy's Merom Station; dual-loop absorbers with perforated-plate trays at Southwestern Electric Power Company's Pirkey Station; horizontal spray absorbers at PSI Energy's Gibson Station; venturi scrubbers at Duquesne Light's Elrama Station; and open stray absorbers at New york State Electric and Gas Corporations's (NYSEG's) Kintigh Station. All operate in an inhibited-oxidation mode except the system at Big Bend (forced oxidation), and all use limestone reagent except the Elrama system (Mg-lime). The program was conducted to demonstrate that upgrades such as performance additives and/or mechanical modifications can increase system SO 2 removal at low cost. The cost effectiveness of each upgrade has been evaluated on the basis of test results and/or process model predictions for upgraded performance and utility-specific operating and maintenance costs. Results from this upgraded performance and utility-specific operating and maintenance costs. Results from this program may lead some utilities to use SO 2 removal upgrades as an approach for compliance with phase 2 of Title IV of the Clean Air Act Amendments (CAAA) of 1990. This paper summarizes the results of testing, modeling, and economic evaluations that have been completed since July, 1994

  11. Research and development of a high efficiency gas-fired water heater. Volume 2. Task reports

    Energy Technology Data Exchange (ETDEWEB)

    Vasilakis, A.D.; Pearson, J.F.; Gerstmann, J.

    1980-01-01

    Design and development of a cost-effective high efficiency gas-fired water heater to attain a service efficiency of 70% (including the effect of exfiltration) and a service efficiency of 78% (excluding exfiltration) for a 75 GPD draw at a 90/sup 0/F temperature rise, with a stored water to conditioned air temperature difference of 80/sup 0/F, are described in detail. Based on concept evaluation, a non-powered natural draft water heater was chosen as the most cost-effective design to develop. The projected installed cost is $374 compared to $200 for a conventional unit. When the project water heater is compared to a conventional unit, it has a payback of 3.7 years and life cycle savings of $350 to the consumer. A prototype water heater was designed, constructed, and tested. When operated with sealed combustion, the unit has a service efficiency of 66.4% (including the effect of exfiltration) below a burner input of 32,000 Btu/h. In the open combustion configuration, the unit operated at a measured efficiency of 66.4% Btu/h (excluding exfiltration). This compares with a service efficiency of 51.3% for a conventional water heater and 61% for a conventional high efficiency unit capable of meeting ASHRAE 90-75. Operational tests showed the unit performed well with no evidence of stacking or hot spots. It met or exceeded all capacity or usage tests specified in the program test plan and met all emission goals. Future work will concentrate on designing, building, and testing pre-production units. It is anticipated that both sealed combustion and open draft models will be pursued.

  12. High-Efficiency, Multijunction Solar Cells for Large-Scale Solar Electricity Generation

    Science.gov (United States)

    Kurtz, Sarah

    2006-03-01

    A solar cell with an infinite number of materials (matched to the solar spectrum) has a theoretical efficiency limit of 68%. If sunlight is concentrated, this limit increases to about 87%. These theoretical limits are calculated using basic physics and are independent of the details of the materials. In practice, the challenge of achieving high efficiency depends on identifying materials that can effectively use the solar spectrum. Impressive progress has been made with the current efficiency record being 39%. Today's solar market is also showing impressive progress, but is still hindered by high prices. One strategy for reducing cost is to use lenses or mirrors to focus the light on small solar cells. In this case, the system cost is dominated by the cost of the relatively inexpensive optics. The value of the optics increases with the efficiency of the solar cell. Thus, a concentrator system made with 35%- 40%-efficient solar cells is expected to deliver 50% more power at a similar cost when compare with a system using 25%-efficient cells. Today's markets are showing an opportunity for large concentrator systems that didn't exist 5-10 years ago. Efficiencies may soon pass 40% and ultimately may reach 50%, providing a pathway to improved performance and decreased cost. Many companies are currently investigating this technology for large-scale electricity generation. The presentation will cover the basic physics and more practical considerations to achieving high efficiency as well as describing the current status of the concentrator industry. This work has been authored by an employee of the Midwest Research Institute under Contract No. DE- AC36-99GO10337 with the U.S. Department of Energy. The United States Government retains and the publisher, by accepting the article for publication, acknowledges that the United States Government retains a non-exclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published form of this work, or allow

  13. High Efficiency, Transparent, Reusable, and Active PM2.5 Filters by Hierarchical Ag Nanowire Percolation Network.

    Science.gov (United States)

    Jeong, Seongmin; Cho, Hyunmin; Han, Seonggeun; Won, Phillip; Lee, Habeom; Hong, Sukjoon; Yeo, Junyeob; Kwon, Jinhyeong; Ko, Seung Hwan

    2017-07-12

    Air quality has become a major public health issue in Asia including China, Korea, and India. Particulate matters are the major concern in air quality. We present the first environmental application demonstration of Ag nanowire percolation network for a novel, electrical type transparent, reusable, and active PM2.5 air filter although the Ag nanowire percolation network has been studied as a very promising transparent conductor in optoelectronics. Compared with previous particulate matter air filter study using relatively weaker short-range intermolecular force in polar polymeric nanofiber, Ag nanowire percolation network filters use stronger long-range electrostatic force to capture PM2.5, and they are highly efficient (>99.99%), transparent, working on an active mode, low power consumption, antibacterial, and reusable after simple washing. The proposed new particulate matter filter can be applied for a highly efficient, reusable, active and energy efficient filter for wearable electronics application.

  14. Dossier high-efficient electric water heater. Electricity by a Stirling engine; Het Dossier HRE-ketel. Stroom uit Stirlingmotor

    Energy Technology Data Exchange (ETDEWEB)

    Scholtens, B.

    2010-10-15

    The market seems ready for a private power plant on the wall in the attic, which also heats the house. Such an installation is the successor of the high efficiency boiler, which is in use in most of the homes in the Netherlands. After fifteen years of development Dutch companies have taken the lead in this technology. The manufacturer Remeha in Apeldoorn, Netherlands, started one month ago with the production of high efficiency electric boiler. [Dutch] De markt lijkt klaar voor een eigen stroomcentrale aan de muur op zolder die bovendien het huis verwarmt. De installatie is de opvolger van de hoogrendementsketel, die de meeste huizen in Nederland verwarmt. Na vijftien jaar ontwikkeling hebben Nederlandse bedrijven het technologische voortouw genomen. De Apeldoornse fabrikant Remeha is een maand geleden als eerste met serieproductie van de hre-ketel begonnen.

  15. An episomal vector-based CRISPR/Cas9 system for highly efficient gene knockout in human pluripotent stem cells.

    Science.gov (United States)

    Xie, Yifang; Wang, Daqi; Lan, Feng; Wei, Gang; Ni, Ting; Chai, Renjie; Liu, Dong; Hu, Shijun; Li, Mingqing; Li, Dajin; Wang, Hongyan; Wang, Yongming

    2017-05-24

    Human pluripotent stem cells (hPSCs) represent a unique opportunity for understanding the molecular mechanisms underlying complex traits and diseases. CRISPR/Cas9 is a powerful tool to introduce genetic mutations into the hPSCs for loss-of-function studies. Here, we developed an episomal vector-based CRISPR/Cas9 system, which we called epiCRISPR, for highly efficient gene knockout in hPSCs. The epiCRISPR system enables generation of up to 100% Insertion/Deletion (indel) rates. In addition, the epiCRISPR system enables efficient double-gene knockout and genomic deletion. To minimize off-target cleavage, we combined the episomal vector technology with double-nicking strategy and recent developed high fidelity Cas9. Thus the epiCRISPR system offers a highly efficient platform for genetic analysis in hPSCs.

  16. Compressor motor for air conditioners realizing high efficiency and low cost; Kokoritsu tei cost wo jitsugenshita eakonyo asshukuki motor

    Energy Technology Data Exchange (ETDEWEB)

    Inaba, Y.; Kawamura, K.; Imazawa, K. [Toshiba Corp., Tokyo (Japan)

    2000-01-01

    The compressor motor accounts for most of the consumption of electric power in an air conditioner. To promote energy-saving, Toshiba has been progressively changing the compressor motors in its air conditioners to high-efficiency brushless DC motors. We have now developed a new compressor motor in order to achieve even greater energy-saving. A concentrated winding system was adopted featuring direct winding on the teeth of the stator core, for the first time in the industry. As a result, it was possible to realize a high-efficiency, compact, lightweight, and low-cost motor. Moreover, by constructing a new system for production, we were able to improve productivity and quality. The newly developed motor is expected to contribute to the further diffusion of energy-saving air conditioners. (author)

  17. Highly efficient hybrid energy generator: coupled organic photovoltaic device and randomly oriented electrospun poly(vinylidene fluoride) nanofiber.

    Science.gov (United States)

    Park, Boongik; Lee, Kihwan; Park, Jongjin; Kim, Jongmin; Kim, Ohyun

    2013-03-01

    A hybrid architecture consisting of an inverted organic photovoltaic device and a randomly-oriented electrospun PVDF piezoelectric device was fabricated as a highly-efficient energy generator. It uses the inverted photovoltaic device with coupled electrospun PVDF nanofibers as tandem structure to convert solar and mechanical vibrations energy to electricity simultaneously or individually. The power conversion efficiency of the photovoltaic device was also significantly improved up to 4.72% by optimized processes such as intrinsic ZnO, MoO3 and active layer. A simple electrospinning method with the two electrode technique was adopted to achieve a high voltage of - 300 mV in PVDF piezoelectric fibers. Highly-efficient HEG using voltage adder circuit provides the conceptual possibility of realizing multi-functional energy generator whenever and wherever various energy sources are available.

  18. A highly efficient Ho:YAG laser in-band pumped by a linewidth-narrowed Tm:YLF laser

    International Nuclear Information System (INIS)

    Duan, X M; Yang, C H; Yao, B Q; Wang, Y Z; Zhang, W S

    2013-01-01

    A highly efficient Tm:YLF-Ho:YAG laser system is presented in this paper. To obtain the narrow linewidth 1908 nm laser output, a volume Bragg grating combined with a Fabry–Perot (FP) etalon were used as wavelength selection devices. The maximum output power of 28.7 W was obtained with a slope efficiency of 42.3% in the Tm:YLF laser. An output wavelength of 1908.1 nm and FWHM linewidth of 60 pm were achieved at the maximum output level. Using this Tm:YLF laser as the pump source, high efficiency continuous wave and Q-switched operation of a Ho:YAG laser was demonstrated. Operating at continuous wave mode, up to 73.3% slope efficiency and 67.4% optical conversion efficiency were obtained in the Ho:YAG laser, corresponding to a diode-to-Ho optical conversion efficiency of 23.7%. For the Q-switched mode, when the incident Tm power was 27.3 W, the maximum single pulse energy of 3.4 mJ, pulse width of 15 ns and peak power of 229.3 kW were achieved at the pulse repetition rate of 5 kHz. The maximum average power of 18.3 W, pulse width of 18 ns and peak power of 103.6 kW were obtained at the pulse repetition rate of 10 kHz. (paper)

  19. High-Efficiency BODIPY-Based Organic Photovoltaics

    KAUST Repository

    Chen, John J.; Conron, Sarah M.; Erwin, Patrick; Dimitriou, Michael; McAlahney, Kyle; Thompson, Mark E.

    2015-01-01

    © 2014 American Chemical Society. A benzannulated boron dipyrromethene (BODIPY, bDIP) molecule exhibiting strong absorption at 640 nm was synthesized. The organic dye was used in an organic solar cell as the electron donor with C60 as the acceptor. The BODIPY dye demonstrated the best performance in lamellar architecture (indium tin oxide (ITO)/bDIP/C60/bathocuproine/Al), giving power conversion efficiency up to 4.5% with short-circuit current (JSC) of 8.7 mA/cm2 and an open-circuit voltage (VOC) of 0.81 V. Neutron reflectivity experiments were performed on the bilayer film to investigate the thickness dependence of JSC. A 13 nm mixed layer was found to be present at the donor/acceptor interface in the bilayer device, formed when the C60 was deposited onto a room temperature bDIP film. Planar-mixed heterojunction devices were fabricated to understand the extent of spontaneous mixing between the donor and acceptor materials. The native mixed region in the bilayer device was shown to most resemble 1:3 bDIP:C60 layer in the structure: (ITO/bDIP/bDIP:C60 blend/C60/bathocuproine/Al).

  20. Highly efficient solar-pumped Nd:YAG laser.

    Science.gov (United States)

    Liang, Dawei; Almeida, Joana

    2011-12-19

    The recent progress in solar-pumped laser with Fresnel lens and Cr:Nd:YAG ceramic medium has revitalized solar laser researches, revealing a promising future for renewable reduction of magnesium from magnesium oxide. Here we show a big advance in solar laser collection efficiency by utilizing an economical Fresnel lens and a most widely used Nd:YAG single-crystal rod. The incoming solar radiation from the sun is focused by a 0.9 m diameter Fresnel lens. A dielectric totally internally reflecting secondary concentrator is employed to couple the concentrated solar radiation from the focal zone to a 4 mm diameter Nd:YAG rod within a conical pumping cavity. 12.3 W cw laser power is produced, corresponding to 19.3 W/m(2) collection efficiency, which is 2.9 times larger than the previous results with Nd:YAG single-crystal medium. Record-high slope efficiency of 3.9% is also registered. Laser beam quality is considerably improved by pumping a 3 mm diameter Nd:YAG rod.

  1. High efficiency electrophosphorescence from bilayer organic light emitting diodes

    Energy Technology Data Exchange (ETDEWEB)

    Li Minghang; Lin, Ming-Te; Shepherd, Nigel D [Department of Material Science and Engineering, University of North Texas, Denton, TX (United States); Chen, Wei-Hsuan; Oswald, Iain; Omary, Mohammad [Department of Chemeistry, University of North Texas, Denton, TX (United States)

    2011-09-14

    An electron mobility of 2.7 x 10{sup -5} cm{sup 2} V{sup -1} s{sup -1} was measured for the phosphorescent emitter bis[3,5-bis(2-pyridyl)-1,2,4-triazolato]platinum(II)(Pt(ptp)2), which prompted its evaluation as both the emissive layer and electron transport layer in organic light emitting diodes with a simple bilayer structure. Power and external quantum efficiencies of 54.0 {+-} 0.2 lm W{sup -1} and 15.9% were obtained, which as far as we could ascertain are amongst the highest reported values for bilayer devices. We ascribe the high device efficiency to the combination of the high electron mobility, short excited-state lifetime (117 ns) and high luminescence quantum yield (60%) of the bis[3,5-bis(2-pyridyl)-1,2,4-triazolato]platinum(II). The colour temperature of the devices was 2855 K at 5 V, which places the emission in the 'warm' light spectral region.

  2. Molecular and Nanoscale Engineering of High Efficiency Excitonic Solar Cells

    Energy Technology Data Exchange (ETDEWEB)

    Jenekhe, Samson A. [Univ. of Washington, Seattle, WA (United States); Ginger, David S. [Univ. of Washington, Seattle, WA (United States); Cao, Guozhong [Univ. of Washington, Seattle, WA (United States)

    2016-01-15

    We combined the synthesis of new polymers and organic-inorganic hybrid materials with new experimental characterization tools to investigate bulk heterojunction (BHJ) polymer solar cells and hybrid organic-inorganic solar cells during the 2007-2010 period (phase I) of this project. We showed that the bulk morphology of polymer/fullerene blend solar cells could be controlled by using either self-assembled polymer semiconductor nanowires or diblock poly(3-alkylthiophenes) as the light-absorbing and hole transport component. We developed new characterization tools in-house, including photoinduced absorption (PIA) spectroscopy, time-resolved electrostatic force microscopy (TR-EFM) and conductive and photoconductive atomic force microscopy (c-AFM and pc-AFM), and used them to investigate charge transfer and recombination dynamics in polymer/fullerene BHJ solar cells, hybrid polymer-nanocrystal (PbSe) devices, and dye-sensitized solar cells (DSSCs); we thus showed in detail how the bulk photovoltaic properties are connected to the nanoscale structure of the BHJ polymer solar cells. We created various oxide semiconductor (ZnO, TiO2) nanostructures by solution processing routes, including hierarchical aggregates and nanorods/nanotubes, and showed that the nanostructured photoanodes resulted in substantially enhanced light-harvesting and charge transport, leading to enhanced power conversion efficiency of dye-sensitized solar cells.

  3. Improper ferroelectrics as high-efficiency energy conversion materials

    Energy Technology Data Exchange (ETDEWEB)

    Wakamatsu, Toru; Tanabe, Kenji; Terasaki, Ichiro; Taniguchi, Hiroki [Department of Physics, Nagoya University, Nagoya 464-8602 (Japan)

    2017-05-15

    An improper ferroelectric is a certain type of ferroelectrics whose primary order parameter is not polarization but another physical quantity such as magnetization. In contrast to a conventional proper ferroelectrics as represented by Pb(Zr,Ti)O{sub 3} and BaTiO{sub 3}, the improper ferroelectrics has been inconceivable for practical applications thus far. Herein, we illustrate the great potential of improper ferroelectrics for efficient conversion of temperature fluctuation to electric energy, as demonstrated with (Ca{sub 0.84}Sr{sub 0.16}){sub 8}[AlO{sub 2}]{sub 12}(MoO{sub 4}){sub 2} (CSAM-16). The present study has experimentally proven that CSAM-16 achieves an excellent electrothermal coupling factor and high electric field sensitivity for pyroelectric energy conversion that approach a practical level for application to self-powered autonomous electronic devices for rapidly spreading wireless sensor networks. The present results provide a novel approach to developing innovative pyroelectric energy harvesting devices using improper ferroelectrics. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  4. Improper ferroelectrics as high-efficiency energy conversion materials

    International Nuclear Information System (INIS)

    Wakamatsu, Toru; Tanabe, Kenji; Terasaki, Ichiro; Taniguchi, Hiroki

    2017-01-01

    An improper ferroelectric is a certain type of ferroelectrics whose primary order parameter is not polarization but another physical quantity such as magnetization. In contrast to a conventional proper ferroelectrics as represented by Pb(Zr,Ti)O_3 and BaTiO_3, the improper ferroelectrics has been inconceivable for practical applications thus far. Herein, we illustrate the great potential of improper ferroelectrics for efficient conversion of temperature fluctuation to electric energy, as demonstrated with (Ca_0_._8_4Sr_0_._1_6)_8[AlO_2]_1_2(MoO_4)_2 (CSAM-16). The present study has experimentally proven that CSAM-16 achieves an excellent electrothermal coupling factor and high electric field sensitivity for pyroelectric energy conversion that approach a practical level for application to self-powered autonomous electronic devices for rapidly spreading wireless sensor networks. The present results provide a novel approach to developing innovative pyroelectric energy harvesting devices using improper ferroelectrics. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  5. High-Efficiency BODIPY-Based Organic Photovoltaics

    KAUST Repository

    Chen, John J.

    2015-01-14

    © 2014 American Chemical Society. A benzannulated boron dipyrromethene (BODIPY, bDIP) molecule exhibiting strong absorption at 640 nm was synthesized. The organic dye was used in an organic solar cell as the electron donor with C60 as the acceptor. The BODIPY dye demonstrated the best performance in lamellar architecture (indium tin oxide (ITO)/bDIP/C60/bathocuproine/Al), giving power conversion efficiency up to 4.5% with short-circuit current (JSC) of 8.7 mA/cm2 and an open-circuit voltage (VOC) of 0.81 V. Neutron reflectivity experiments were performed on the bilayer film to investigate the thickness dependence of JSC. A 13 nm mixed layer was found to be present at the donor/acceptor interface in the bilayer device, formed when the C60 was deposited onto a room temperature bDIP film. Planar-mixed heterojunction devices were fabricated to understand the extent of spontaneous mixing between the donor and acceptor materials. The native mixed region in the bilayer device was shown to most resemble 1:3 bDIP:C60 layer in the structure: (ITO/bDIP/bDIP:C60 blend/C60/bathocuproine/Al).

  6. A High-Efficiency Voltage Equalization Scheme for Supercapacitor Energy Storage System in Renewable Generation Applications

    Directory of Open Access Journals (Sweden)

    Liran Li

    2016-06-01

    Full Text Available Due to its fast charge and discharge rate, a supercapacitor-based energy storage system is especially suitable for power smoothing in renewable energy generation applications. Voltage equalization is essential for series-connected supercapacitors in an energy storage system, because it supports the system’s sustainability and maximizes the available cell energy. In this paper, we present a high-efficiency voltage equalization scheme for supercapacitor energy storage systems in renewable generation applications. We propose an improved isolated converter topology that uses a multi-winding transformer. An improved push-pull forward circuit is applied on the primary side of the transformer. A coupling inductor is added on the primary side to allow the switches to operate under the zero-voltage switching (ZVS condition, which reduces switching losses. The diodes in the rectifier are replaced with metal-oxide-semiconductor field-effect transistors (MOSFETs to reduce the power dissipation of the secondary side. In order to simplify the control, we designed a controllable rectifying circuit to achieve synchronous rectifying on the secondary side of the transformer. The experimental results verified the effectiveness of the proposed design.

  7. Highly Efficient, Zero-Skew, Integrated Clock Distribution Networks Using Salphasic Principles

    Directory of Open Access Journals (Sweden)

    PASCA, A.

    2016-02-01

    Full Text Available The design of highly efficient clock distributions for integrated circuits is an active topic of research as there will never be a single solution for all systems. For high performance digital or mixed-signal circuits, achieving zero-skew clock over large areas usually comes with high costs in power requirements and design complexity. The present paper shows an overview of a recently proposed technique for ICs - on-die salphasic clock distribution, introduced by the author for CMOS processes. Initially reported in literature for rack-systems, the present paper shows that further refinements are needed for the concept to be applicable on a silicon die. Based on the formation of a standing wave (intrinsically presenting extended in-phase regions with a voltage peak at the input (creating a no-load condition, it is shown that any IC implementation must use transmission lines loss compensation techniques to maintain the proper standing wave configuration. Furthermore, the paper shows theoretical solutions and describes practical on-die techniques for pseudo-spherical bidimensional surfaces, which, with the already reported orthogonal and pseudo-orthogonal structures, can be used to distribute with minimal power requirements a zero-skew clock signal, over large silicon areas.

  8. A highly efficient multi-core algorithm for clustering extremely large datasets

    Directory of Open Access Journals (Sweden)

    Kraus Johann M

    2010-04-01

    Full Text Available Abstract Background In recent years, the demand for computational power in computational biology has increased due to rapidly growing data sets from microarray and other high-throughput technologies. This demand is likely to increase. Standard algorithms for analyzing data, such as cluster algorithms, need to be parallelized for fast processing. Unfortunately, most approaches for parallelizing algorithms largely rely on network communication protocols connecting and requiring multiple computers. One answer to this problem is to utilize the intrinsic capabilities in current multi-core hardware to distribute the tasks among the different cores of one computer. Results We introduce a multi-core parallelization of the k-means and k-modes cluster algorithms based on the design principles of transactional memory for clustering gene expression microarray type data and categorial SNP data. Our new shared memory parallel algorithms show to be highly efficient. We demonstrate their computational power and show their utility in cluster stability and sensitivity analysis employing repeated runs with slightly changed parameters. Computation speed of our Java based algorithm was increased by a factor of 10 for large data sets while preserving computational accuracy compared to single-core implementations and a recently published network based parallelization. Conclusions Most desktop computers and even notebooks provide at least dual-core processors. Our multi-core algorithms show that using modern algorithmic concepts, parallelization makes it possible to perform even such laborious tasks as cluster sensitivity and cluster number estimation on the laboratory computer.

  9. Magnetic Refrigeration Technology for High Efficiency Air Conditioning

    Energy Technology Data Exchange (ETDEWEB)

    Boeder, A; Zimm, C

    2006-09-30

    Magnetic refrigeration was investigated as an efficient, environmentally friendly, flexible alternative to conventional residential vapor compression central air conditioning systems. Finite element analysis (FEA) models of advanced geometry active magnetic regenerator (AMR) beds were developed to minimize bed size and thus magnet mass by optimizing geometry for fluid flow and heat transfer and other losses. Conventional and magnetocaloric material (MCM) regenerator fabrication and assembly techniques were developed and advanced geometry passive regenerators were built and tested. A subscale engineering prototype (SEP) magnetic air conditioner was designed, constructed and tested. A model of the AMR cycle, combined with knowledge from passive regenerator experiments and FEA results, was used to design the regenerator beds. A 1.5 Tesla permanent magnet assembly was designed using FEA and the bed structure and plenum design was extensively optimized using FEA. The SEP is a flexible magnetic refrigeration platform, with individually instrumented beds and high flow rate and high frequency capability, although the current advanced regenerator geometry beds do not meet performance expectations, probably due to manufacturing and assembly tolerances. A model of the AMR cycle was used to optimize the design of a 3 ton capacity magnetic air conditioner, and the system design was iterated to minimize external parasitic losses such as heat exchanger pressure drop and fan power. The manufacturing cost for the entire air conditioning system was estimated, and while the estimated SEER efficiency is high, the magnetic air conditioning system is not cost competitive as currently configured. The 3 ton study results indicate that there are other applications where magnetic refrigeration is anticipated to have cost advantages over conventional systems, especially applications where magnetic refrigeration, through the use of its aqueous heat transfer fluid, could eliminate intermediate

  10. High-efficiency, 154  W CW, diode-pumped Raman fiber laser with brightness enhancement.

    Science.gov (United States)

    Glick, Yaakov; Fromzel, Viktor; Zhang, Jun; Ter-Gabrielyan, Nikolay; Dubinskii, Mark

    2017-01-20

    We demonstrate a high-power, high-efficiency Raman fiber laser pumped directly by laser diode modules at 978 nm. 154 W of CW power were obtained at a wavelength of 1023 nm with an optical to optical efficiency of 65%. A commercial graded-index (GRIN) core fiber acts as the Raman fiber in a power oscillator configuration, which includes spectral selection to prevent generation of the second Stokes. In addition, brightness enhancement of the pump beam by a factor of 8.4 is attained due to the Raman gain distribution profile in the GRIN fiber. To the best of our knowledge this is the highest power and highest efficiency Raman fiber laser demonstrated in any configuration allowing brightness enhancement (i.e., in either cladding-pumped configuration or with GRIN fibers, excluding step-index core pumped), regardless of pumping scheme (i.e., either diode pumped or fiber laser pumped).

  11. Novel Low Cost Organic Vapor Jet Printing of Striped High Efficiency Phosphorescent OLEDs for White Lighting

    Energy Technology Data Exchange (ETDEWEB)

    Mike Hack

    2008-12-31

    In this program, Universal Display Corporation and University of Michigan proposed to integrate three innovative concepts to meet the DOE's Solid State Lighting (SSL) goals: (1) high-efficiency phosphorescent organic light emitting device (PHOLED{trademark}) technology, (2) a white lighting design that is based on a series of red, green and blue OLED stripes, and (3) the use of a novel cost-effective, high rate, mask-less deposition process called organic vapor jet printing (OVJP). Our PHOLED technology offers up to four-times higher power efficiency than other OLED approaches for general lighting. We believe that one of the most promising approaches to maximizing the efficiency of OLED lighting sources is to produce stripes of the three primary colors at such a pitch (200-500 {mu}m) that they appear as a uniform white light to an observer greater than 1 meter (m) away from the illumination source. Earlier work from a SBIR Phase 1 entitled 'White Illumination Sources Using Striped Phosphorescent OLEDs' suggests that stripe widths of less than 500 {mu}m appear uniform from a distance of 1m without the need for an external diffuser. In this program, we intend to combine continued advances in this PHOLED technology with the striped RGB lighting design to demonstrate a high-efficiency, white lighting source. Using this background technology, the team has focused on developing and demonstrating the novel cost-effective OVJP process to fabricate these high-efficiency white PHOLED light sources. Because this groundbreaking OVJP process is a direct printing approach that enables the OLED stripes to be printed without a shadow mask, OVJP offers very high material utilization and high throughput without the costs and wastage associated with a shadow mask (i.e. the waste of material that deposits on the shadow mask itself). As a direct printing technique, OVJP also has the potential to offer ultra-high deposition rates (> 1,000 Angstroms/second) for any size or

  12. Wide-Range Highly-Efficient Wireless Power Receivers for Implantable Biomedical Sensors

    KAUST Repository

    Ouda, Mahmoud

    2016-01-01

    for implantable devices or IoT nodes. A custom setup is developed to test the chip in a saline solution with electrical properties similar to those of the aqueous humor of the eye. The proposed chip, in this eye-like setup, is wirelessly charged to 1V from a 5W

  13. Development of a high-efficiency hydrogen generator for fuel cells for distributed power generation

    Energy Technology Data Exchange (ETDEWEB)

    Duraiswamy, K.; Chellappa, Anand [Intelligent Energy, 2955 Redondo Ave., Long Beach, CA 90806 (United States); Smith, Gregory; Liu, Yi; Li, Mingheng [Department of Chemical and Materials Engineering, California State Polytechnic University, Pomona, CA 91768 (United States)

    2010-09-15

    A collaborative effort between Intelligent Energy and Cal Poly Pomona has developed an adsorption enhanced reformer (AER) for hydrogen generation for use in conjunction with fuel cells in small sizes. The AER operates at a lower temperature (about 500 C) and has a higher hydrogen yield and purity than those in the conventional steam reforming. It employs ceria supported rhodium as the catalyst and potassium-promoted hydrotalcites to remove carbon dioxide from the products. A novel pulsing feed concept is developed for the AER operation to allow a deeper conversion of the feedstock to hydrogen. Continuous production of near fuel-cell grade hydrogen is demonstrated in the AER with four packed beds running alternately. In the best case of methane reforming, the overall conversion to hydrogen is 92% while the carbon dioxide and carbon monoxide concentrations in the production stream are on the ppm level. The ratio of carbon dioxide in the regeneration exhaust to the one in the product stream is on the order of 10{sup 3}. (author)

  14. High Efficiency Space Power Systems Project Advanced Space-Rated Batteries

    Science.gov (United States)

    Reid, Concha M.

    2011-01-01

    Case Western Reserve University (CWRU) has an agreement with China National Offshore Oil Corporation New Energy Investment Company, Ltd. (CNOOC), under the United States-China EcoPartnerships Framework, to create a bi-national entity seeking to develop technically feasible and economically viable solutions to energy and environmental issues. Advanced batteries have been identified as one of the initial areas targeted for collaborations. CWRU invited NASA Glenn Research Center (GRC) personnel from the Electrochemistry Branch to CWRU to discuss various aspects of advanced battery development as they might apply to this partnership. Topics discussed included: the process for the selection of a battery chemistry; the establishment of an integrated development program; project management/technical interactions; new technology developments; and synergies between batteries for automotive and space operations. Additional collaborations between CWRU and NASA GRC's Electrochemistry Branch were also discussed.

  15. Design, characterization and modelling of high efficient solar powered lighting systems

    DEFF Research Database (Denmark)

    Svane, Frederik; Nymann, Peter; Poulsen, Peter Behrensdorff

    2016-01-01

    This paper discusses some of the major challenges in the development of L2L (Light-2-Light) products. It’s the lack of efficient converter electronics, modelling tools for dimensioning and furthermore, characterization facilities to support the successful development of the products. We report...

  16. High-Efficiency, High-Power Laser Transmitter for Deep-Space Communication, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — There is demand for vastly improved deep space satellite communications links. As data rates dramatically increase due to new sensor technologies and the desire to...

  17. High Efficiency Quantum Dot III-V Multijunction Solar Cell for Space Power, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Quantum dots are nanoscale materials that have already improved the performance of optical sensors, lasers, and light emitting diodes. The unique properties of these...

  18. High Efficiency Quantum Dot III-V Thermophotovoltaic Cell for Space Power, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Quantum dots are nanoscale materials that have already improved the performance of optical sensors, lasers, light emitting diodes and solar cells. The unique...

  19. Nanocoatings for High-Efficiency Industrial Hydraulic and Tooling Systems

    Energy Technology Data Exchange (ETDEWEB)

    Clifton B. Higdon III

    2011-01-07

    energy conservation. In mobile hydraulic systems, efficiency gains through low friction would translate into improved fuel economy and fewer greenhouse gas emissions. Stationary hydraulic systems, accordingly, would consume less electrical power. Reduced tooling wear in machining operations would translate to greater operating yields, while lowering the energy consumed during processing. The AlMgB14 nanocoatings technology progressed beyond baseline laboratory tests into measurable energy savings and enhancements to product durability. Three key hydraulic markets were identified over the course of the project that will benefit from implementation: industrial vane pumps, orbiting valve-in-star hydraulic motors, and variable displacement piston pumps. In the vane pump application, the overall product efficiency was improved by as much as 11%. Similar results were observed with the hydraulic motors tested, where efficiency gains of over 10% were noted. For variable displacement piston pumps, overall efficiency was improved by 5%. For cutting tools, the most significant gains in productivity (and, accordingly, the efficiency of the machining process as a whole) were associated with the roughing and finishing of titanium components for aerospace systems. Use of the AlMgB14 nanocoating in customer field tests has shown that the coated tools were able to withstand machining rates as high as 500sfm (limited only by the substrate material), with relatively low flank wear when compared to other industrial offerings. AlMgB14 coated tools exhibited a 60% improvement over similarly applied TiAlN thin films. Furthermore, AlMgB14-based coatings in these particular tests lasted twice as long than their TiAlN counterparts at the 500sfm feed rates. Full implementation of the technology into the industrial hydraulic and cutting tool markets equates to a worldwide energy savings of 46 trillion BTU/year by 2030. U.S.-based GHG emissions associated with the markets identified would fall

  20. Progress in N-type Si Solar Cell and Module Technology for High Efficiency and Low Cost

    Energy Technology Data Exchange (ETDEWEB)

    Song, Dengyuan; Xiong, Jingfeng; Hu, Zhiyan; Li, Gaofei; Wang, Hongfang; An, Haijiao; Yu, Bo; Grenko, Brian; Borden, Kevin; Sauer, Kenneth; Cui, Jianhua; Wang, Haitao [Yingli Green Energy Holding Co., LTD, 071051 Boading (China); Roessler, T. [Yingli Green Energy Europe GmbH, Heimeranstr. 37, 80339 Munich (Germany); Bultman, J. [ECN Solar Energy, P.O. Box 1, NL-1755 ZG Petten (Netherlands); Vlooswijk, A.H.G.; Venema, P.R. [Tempress Systems BV, Radeweg 31, 8171 Vaassen (Netherlands)

    2012-06-15

    A novel high efficiency solar cell and module technology, named PANDA, using crystalline n-type CZ Si wafers has moved into large-scale production at Yingli. The first commercial sales of the PANDA modules commenced in mid 2010. Up to 600MW of mass production capacity from crystal-Si growth, wafer slicing, cell processing and module assembly have been implemented by the end of 2011. The PANDA technology was developed specifically for high efficiency and low cost. In contrast to the existing n-type Si solar cell manufacturing methods in mass production, this new technology is largely compatible with a traditional p-type Si solar cell production line by conventional diffusion, SiNx coating and screen-printing technology. With optimizing all technologies, Yingli's PANDA solar cells on semi-square 6-inch n-type CZ wafers (cell size 239cm{sup 2}) have been improved to currently have an average efficiency on commercial production lines exceeding 19.0% and up to 20.0% in pilot production. The PANDA modules have been produced and were certified according to UL1703, IEC 61215 and IEC 61730 standards. Nearly two years of full production on scale-up lines show that the PANDA modules have a high efficiency and power density, superior high temperature performance, near zero initial light induced degradation, and excellent efficiency at low irradiance.

  1. High-Efficiency Isolated Photovoltaic Microinverter Using Wide-Band Gap Switches for Standalone and Grid-Tied Applications

    Directory of Open Access Journals (Sweden)

    Yu-Chen Liu

    2018-03-01

    Full Text Available An isolated photovoltaic micro-inverter for standalone and grid-tied applications is designed and implemented to achieve high efficiency. System configuration and design considerations, including the proposed active-clamp forward-flyback resonant converter for the DC-DC stage and a dual-frequency full-bridge inverter for the DC-AC stage, are analyzed and discussed. A prototype microinverter system is built and tested. Experimental results verify the feasibility of the proposed system, which achieves 95% power conversion efficiency at full load.

  2. Highly efficient greenish-blue platinum-based phosphorescent organic light-emitting diodes on a high triplet energy platform

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Y. L., E-mail: yilu.chang@mail.utoronto.ca; Gong, S., E-mail: sgong@chem.utoronto.ca; White, R.; Lu, Z. H., E-mail: zhenghong.lu@utoronto.ca [Department of Materials Science and Engineering, University of Toronto, 184 College St., Toronto, Ontario M5S 3E4 (Canada); Wang, X.; Wang, S., E-mail: wangs@chem.queensu.ca [Department of Chemistry, Queen' s University, 90 Bader Lane, Kingston, Ontario K7L 3N6 (Canada); Yang, C. [Department of Chemistry, Wuhan University, Wuhan 430072 (China)

    2014-04-28

    We have demonstrated high-efficiency greenish-blue phosphorescent organic light-emitting diodes (PHOLEDs) based on a dimesitylboryl-functionalized C^N chelate Pt(II) phosphor, Pt(m-Bptrz)(t-Bu-pytrz-Me). Using a high triplet energy platform and optimized double emissive zone device architecture results in greenish-blue PHOLEDs that exhibit an external quantum efficiency of 24.0% and a power efficiency of 55.8 lm/W. This record high performance is comparable with that of the state-of-the-art Ir-based sky-blue organic light-emitting diodes.

  3. Sugar microanalysis by HPLC with benzoylation: improvement via introduction of a C-8 cartridge and a high efficiency ODS column.

    Science.gov (United States)

    Miyagi, Michiko; Yokoyama, Hirokazu; Hibi, Toshifumi

    2007-07-01

    An HPLC protocol for sugar microanalysis based on the formation of ultraviolet-absorbing benzoyl chloride derivatives was improved. Here, samples were prepared with a C-8 cartridge and analyzed with a high efficiency ODS column, in which porous spherical silica particles 3 microm in diameter were packed. These devices allowed us to simultaneously quantify multiple sugars and sugar alcohols up to 10 ng/ml and to provide satisfactory separations of some sugars, such as fructose and myo-inositol and sorbitol and mannitol. This protocol, which does not require special apparatuses, should become a powerful tool in sugar research.

  4. Development of high-efficiency laser Thomson scattering measurement system for the investigation of EEDF in surface wave plasma

    International Nuclear Information System (INIS)

    Aramaki, M.; Kobayashi, J.; Kono, A.; Stamate, E.; Sugai, H.

    2006-01-01

    A high-efficiency multichannel Thomson scattering measurement system was developed as a tool for studying the electron heating mechanisms in a surface wave plasma. By improving the output power and repetition rate of the Nd:YAG laser, an F-number of spectrograph, and a quantum efficiency of ICCD camera, the overall Thomson signal collection efficiency per unit measurement time has been improved by a factor larger than 40 in comparison with the previous measurement system developed by the authors. The one-dimensional electron velocity distribution functions were measured in the vicinity of the dielectric window of a surface wave plasma

  5. High-energy high-efficiency Nd:YLF laser end-pump by 808 nm diode

    Science.gov (United States)

    Ma, Qinglei; Mo, Haiding; Zhao, Jay

    2018-04-01

    A model is developed to calculate the optimal pump position for end-pump configuration. The 808 nm wing pump is employed to spread the absorption inside the crystal. By the optimal laser cavity design, a high-energy high-efficiency Nd:YLF laser operating at 1053 nm is presented. In cw operation, a 13.6 W power is obtained with a slope efficiency of 51% with respect to 30 W incident pump power. The beam quality is near diffraction limited with M2 ∼ 1.02. In Q-switch operation, a pulse energy of 5 mJ is achieved with a peak power of 125 kW at 1 kHz repetition rate.

  6. Graphene-based vdW heterostructure Induced High-efficiency Thermoelectric Devices

    Science.gov (United States)

    Liang, Shijun; Ang, Lay Kee

    Thermoelectric material (TE) can convert the heat into electricity to provide green energy source and its performance is characterized by a figure of merit (ZT) parameter. Traditional TE materials only give ZT equal to around 1 at room temperature. But, it is believed that materials with ZT >3 will find wide applications at this low temperature range. Prior studies have implied that the interrelation between electric conductivity and lattice thermal conductivity renders the goal of engineering ZT of bulk materials to reach ZT >3. In this work, we propose a high-efficiency van del Waals (vdW) heterostructure-based thermionic device with graphene electrodes, which is able to harvest wasted heat (around 400K) based on the newly established thermionic emission law of graphene electrodes instead of Seebeck effect, to boost the efficiency of power generation over 10% around room temperature. The efficiency can be above 20% if the Schottky barrier height and cross-plane lattice thermal conductivity of transition metal dichacogenides (TMD) materials can be fine-engineered. As a refrigerator at 260 K, the efficiency is 50% to 80% of Carnot efficiency. Finally, we identify two TMD materials as the ideal candidates of graphene/TMD/graphene devices based on the state-of-art technology.

  7. Design of a high efficiency relativistic backward wave oscillator with low guiding magnetic field

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xiaoze; Song, Wei; Tan, Weibing; Zhang, Ligang; Su, Jiancang; Zhu, Xiaoxin; Hu, Xianggang; Shen, Zhiyuan; Liang, Xu; Ning, Qi [Science and Technology on High Power Microwave Laboratory, Northwest Institute of Nuclear Technology, Xi' an 710024 (China)

    2016-07-15

    A high efficiency relativistic backward wave oscillator working at a low guiding magnetic field is designed and simulated. A trapezoidal resonant reflector is used to reduce the modulation field in the resonant reflector to avoid overmodulation of the electron beam which will lead to a large momentum spread and then low conversion efficiency. The envelope of the inner radius of the slow wave structure (SWS) increases stepwise to keep conformal to the trajectory of the electron beam which will alleviate the bombardment of the electron on the surface of the SWS. The length of period of the SWS is reduced gradually to make a better match between phase velocity and electron beam, which decelerates continually and improves the RF current distribution. Meanwhile the modulation field is reduced by the introduction of nonuniform SWS also. The particle in cell simulation results reveal that a microwave with a power of 1.8 GW and a frequency of 14.7 GHz is generated with an efficiency of 47% when the diode voltage is 620 kV, the beam current 6.1 kA, and the guiding magnetic field 0.95 T.

  8. High Efficiency Inverted Organic Solar Cells with a Neutral Fulleropyrrolidine Electron Collecting Interlayer

    KAUST Repository

    Xu, Weidong; Yan, Congfei; Kan, Zhipeng; Wang, Yang; Lai, Wen-Yong; Huang, Wei

    2016-01-01

    A novel fulleropyrrolidine derivative, named as FPNOH, was designed, synthesized and utilized as an efficient electron-collecting (EC) layer for inverted organic solar cells (i-OSCs). The grafted diethanolamino-polar moieties can not only trigger its function as an EC interlayer, but also induce orthogonal solubility that guarantees subsequent multi-layer processing without interfacial mixing. A higher power conversion efficiency (PCE) value of 8.34% was achieved for i-OSC devices with ITO/FPNOH EC electrode, compared to that of the sol-gel ZnO based reference devices with an optimized PCE value of 7.92%. High efficiency exceeding 7.7% was still achieved even for the devices with a relatively thick PFNOH film (16.9 nm). It is worthwhile to mention that this kind of material exhibits less thickness dependent performance, in contrast to widely utilized p-type conjugated polyelectrolytes (CPEs) as well as the non-conjugated polyelectrolytes (NCPEs). Further investigation on illuminating intensity dependent parameters revealed the role of FPNOH in reducing interfacial traps-induced recombination at ITO/active layer interface.

  9. High Efficiency Inverted Organic Solar Cells with a Neutral Fulleropyrrolidine Electron Collecting Interlayer

    KAUST Repository

    Xu, Weidong

    2016-05-20

    A novel fulleropyrrolidine derivative, named as FPNOH, was designed, synthesized and utilized as an efficient electron-collecting (EC) layer for inverted organic solar cells (i-OSCs). The grafted diethanolamino-polar moieties can not only trigger its function as an EC interlayer, but also induce orthogonal solubility that guarantees subsequent multi-layer processing without interfacial mixing. A higher power conversion efficiency (PCE) value of 8.34% was achieved for i-OSC devices with ITO/FPNOH EC electrode, compared to that of the sol-gel ZnO based reference devices with an optimized PCE value of 7.92%. High efficiency exceeding 7.7% was still achieved even for the devices with a relatively thick PFNOH film (16.9 nm). It is worthwhile to mention that this kind of material exhibits less thickness dependent performance, in contrast to widely utilized p-type conjugated polyelectrolytes (CPEs) as well as the non-conjugated polyelectrolytes (NCPEs). Further investigation on illuminating intensity dependent parameters revealed the role of FPNOH in reducing interfacial traps-induced recombination at ITO/active layer interface.

  10. Highly efficient blue OLEDs based on diphenylaminofluorenylstyrenes end-capped with heterocyclic aromatics

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Suhyun [Department of Chemistry, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Lee, Kum Hee; Kim, Young Kwan [Department of Information Display, Hongik University, Seoul 121-791 (Korea, Republic of); Yoon, Seung Soo, E-mail: ssyoon@skku.edu [Department of Chemistry, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of)

    2012-10-15

    In this paper, we have designed four diphenylaminofluorenylstyrene derivatives end-capped with heterocyclic aromatic groups, such as 9-phenylcabazole, 4-dibenzofuran, 2-benzoxazole, 2-quinoxaline, respectively. These materials showed blue to red fluorescence with maximum emission wavelengths of 476–611 nm, respectively, which were dependent on the structural and electronic nature of end-capping groups. To explore the electroluminescent properties of these materials, multilayer OLEDs were fabricated in the following sequence: ITO/DNTPD (40 nm)/NPB (20 nm)/2% doped in MADN (20 nm)/Alq{sub 3} (40 nm)/Liq. (1 nm)/Al. Among those, a device exhibited a highly efficient blue emission with the maximum luminance of 14,480 cd/m{sup 2} at 9 V, the luminous efficiency of 5.38 cd/A at 20 mA/cm{sup 2}, power efficiency of 2.77 lm/W at 20 mA/cm{sup 2}, and CIE{sub x,y} coordinates of (0.147, 0.152) at 8 V, respectively.

  11. High efficiency charge recuperation for electron beams of MeV energies

    International Nuclear Information System (INIS)

    MacLachlan, J.A.

    1996-05-01

    Electron cooling of ion beams with energies of some GeV per nucleon requires high-quality electron beams of MeV energies and currents as high as several amperes. The enormous beam power dictates that the beam current be returned to the high voltage terminal which provides the accelerating potential. The beam is returned to a carefully designed collector within the terminal and biased a few kV positive with respect to it. Thus the load on the HV supply is only the accelerating potential times the sum of the beam current loss and the current used to maintain a graded potential on the accelerating structure. If one employs an electrostatic HV supply like a Van de Graaff with maximum charging current of a few hundred microA, the permissible fractional loss is ∼ 10 -4 . During the 15 years or so the concept of medium energy electron cooling has been evolving, the need to demonstrate the practicability of such high efficiency beam recovery has been recognized. This paper will review some experimental tests and further experiments which have been proposed. The design and status are presented for a new re-circulation experiment at 2 MV being carried out by Fermilab at National Electrostatics Corp

  12. Development of High Efficiency and Low Emission Low Temperature Combustion Diesel Engine with Direct EGR Injection

    Science.gov (United States)

    Ho, R. J.; Kumaran, P.; Yusoff, M. Z.

    2016-03-01

    Focus on energy and environmental sustainability policy has put automotive research & development directed to developing high efficiency and low pollutant power train. Diffused flame controlled diesel combustion has reach its limitation and has driven R&D to explore other modes of combustions. Known effective mode of combustion to reduce emission are Low temperature combustion (LTC) and homogeneous charge combustion ignition by suppressing Nitrogen Oxide(NOx) and Particulate Matter (PM) formation. The key control to meet this requirement are chemical composition and distribution of fuel and gas during a combustion process. Most research to accomplish this goal is done by manipulating injected mass flow rate and varying indirect EGR through intake manifold. This research paper shows viable alternative direct combustion control via co-axial direct EGR injection with fuel injection process. A simulation study with OpenFOAM is conducted by varying EGR injection velocity and direct EGR injector diameter performed with under two conditions with non-combustion and combustion. n-heptane (C7H16) is used as surrogate fuel together with 57 species 290 semi-detailed chemical kinetic model developed by Chalmers University is used for combustion simulation. Simulation result indicates viability of co-axial EGR injection as a method for low temperature combustion control.

  13. Feasibility survey on international cooperation for high efficiency energy conversion technology in fiscal 1993

    Science.gov (United States)

    1994-03-01

    Following cooperative researches on fuel cell jointly conducted by NEDO and EGAT (Electricity Generating Authority of Thailand), the survey on international cooperation relating to high efficiency energy conversion technology was carried out for the ASEAN countries. The paper summed up the results of the survey. The study of the international cooperation is made for the following three items: a program for periodical exchange of information with EGAT, a project for cooperative research on phosphoric acid fuel cell in Indonesia, and a project for cooperative research with EGAT on electric power storage by advanced battery. In Malaysia, which is small in scale of state, part of the Ministry of Energy, Telecommunication and Posts is only in charge of the energy issue. Therefore, the situation is that they cannot answer well to many items of research/development cooperation brought in from Japan. The item of medium- and long-term developmental research in the Philippines is about the problems which are seen subsequently in the Manila metropolitan area where the problem of outage is being settled. Accordingly, it is essential to promote the cooperative research, well confirming policies and systems of the Ministry of Energy and the national electricity corporation.

  14. Highly Efficient Light-Driven TiO2-Au Janus Micromotors.

    Science.gov (United States)

    Dong, Renfeng; Zhang, Qilu; Gao, Wei; Pei, Allen; Ren, Biye

    2016-01-26

    A highly efficient light-driven photocatalytic TiO2-Au Janus micromotor with wireless steering and velocity control is described. Unlike chemically propelled micromotors which commonly require the addition of surfactants or toxic chemical fuels, the fuel-free Janus micromotor (diameter ∼1.0 μm) can be powered in pure water under an extremely low ultraviolet light intensity (2.5 × 10(-3) W/cm(2)), and with 40 × 10(-3) W/cm(2), they can reach a high speed of 25 body length/s, which is comparable to common Pt-based chemically induced self-electrophoretic Janus micromotors. The photocatalytic propulsion can be switched on and off by incident light modulation. In addition, the speed of the photocatalytic TiO2-Au Janus micromotor can be accelerated by increasing the light intensity or by adding low concentrations of chemical fuel H2O2 (i.e., 0.1%). The attractive fuel-free propulsion performance, fast movement triggering response, low light energy requirement, and precise motion control of the TiO2-Au Janus photocatalytic micromotor hold considerable promise for diverse practical applications.

  15. Parallel and series FED microstrip array with high efficiency and low cross polarization

    Science.gov (United States)

    Huang, John (Inventor)

    1995-01-01

    A microstrip array antenna for vertically polarized fan beam (approximately 2 deg x 50 deg) for C-band SAR applications with a physical area of 1.7 m by 0.17 m comprises two rows of patch elements and employs a parallel feed to left- and right-half sections of the rows. Each section is divided into two segments that are fed in parallel with the elements in each segment fed in series through matched transmission lines for high efficiency. The inboard section has half the number of patch elements of the outboard section, and the outboard sections, which have tapered distribution with identical transmission line sections, terminated with half wavelength long open-circuit stubs so that the remaining energy is reflected and radiated in phase. The elements of the two inboard segments of the two left- and right-half sections are provided with tapered transmission lines from element to element for uniform power distribution over the central third of the entire array antenna. The two rows of array elements are excited at opposite patch feed locations with opposite (180 deg difference) phases for reduced cross-polarization.

  16. Research Update: Behind the high efficiency of hybrid perovskite solar cells

    Directory of Open Access Journals (Sweden)

    Azhar Fakharuddin

    2016-09-01

    Full Text Available Perovskite solar cells (PSCs marked tremendous progress in a short period of time and offer bright hopes for cheap solar electricity. Despite high power conversion efficiency >20%, its poor operational stability as well as involvement of toxic, volatile, and less-abundant materials hinders its practical deployment. The fact that degradation and toxicity are typically observed in the most successful perovskite involving organic cation and toxic lead, i.e., CH3NH3PbX3, requires a deep understanding of their role in photovoltaic performance in order to envisage if a non-toxic, stable yet highly efficient device is feasible. Towards this, we first provide an overview of the basic chemistry and physics of halide perovskites and its correlation with its extraordinary properties such as crystal structure, bandgap, ferroelectricity, and electronic transport. We then discuss device related aspects such as the various device designs in PSCs and role of interfaces in origin of PV parameters particularly open circuit voltage, various film processing methods and their effect on morphology and characteristics of perovskite films, and the origin and elimination of hysteresis and operational stability in these devices. We then identify future perspectives for stable and efficient PSCs for practical deployment.

  17. Progress in target materials for high-efficiency X-ray backlight

    International Nuclear Information System (INIS)

    Du Ai; Zhou Bin; Li Longxiang; Zhu Xiurong; Li Yu'nong; Shen Jun; Gao Guohua; Zhang Zhihua; Wu Guangming

    2012-01-01

    The composition, microstructure and density of the target materials are the key parameters to determinate the photon energy and intensity of the laser-induced X-ray backlight. Thus the classification of backlight targets, the preparation of target materials and the interaction between targets and high power laser were introduced in this paper. Underdense targets were more competitive than traditional dense targets among the backlight targets. Nano-structured foam targets, which could be classified into nanofiber targets and aerogel targets, were regarded as novel high-efficiency underdense targets. Nanofiber, which was commonly prepared via electro spinning and thermal treatment, exhibited good formability and high concentration of emission atoms; while aerogel, which was prepared via sol-gel processes and supercritical fluid drying, possesses the advantages of homogeneous microstructure and theoretically high conversion efficiency, but accompanied with the disadvantages of complex synthetic processes and low concentration of emission atoms. To prepare monolithic aerogels with low density and high concentration of emission atoms via combined sol-gel theories may be the better design for the development of the laser-induced X-ray backlight. (authors)

  18. Selectively Modulating Triplet Exciton Formation in Host Materials for Highly Efficient Blue Electrophosphorescence.

    Science.gov (United States)

    Li, Huanhuan; Bi, Ran; Chen, Ting; Yuan, Kai; Chen, Runfeng; Tao, Ye; Zhang, Hongmei; Zheng, Chao; Huang, Wei

    2016-03-23

    The concept of limiting the triplet exciton formation to fundamentally alleviate triplet-involved quenching effects is introduced to construct host materials for highly efficient and stable blue phosphorescent organic light-emitting diodes (PhOLEDs). The low triplet exciton formation is realized by small triplet exciton formation fraction and rate with high binding energy and high reorganization energy of triplet exciton. Demonstrated in two analogue molecules in conventional donor-acceptor molecule structure for bipolar charge injection and transport with nearly the same frontier orbital energy levels and triplet excited energies, the new concept host material shows significantly suppressed triplet exciton formation in the host to avoid quenching effects, leading to much improved device efficiencies and stabilities. The low-voltage-driving blue PhOLED devices exhibit maximum efficiencies of 43.7 cd A(-1) for current efficiency, 32.7 lm W(-1) for power efficiency, and 20.7% for external quantum efficiency with low roll-off and remarkable relative quenching effect reduction ratio up to 41%. Our fundamental solution for preventing quenching effects of long-lived triplet excitons provides exciting opportunities for fabricating high-performance devices using the advanced host materials with intrinsically small triplet exciton formation cross section.

  19. Exciplex-Forming Cohost for High Efficiency and High Stability Phosphorescent Organic Light-Emitting Diodes.

    Science.gov (United States)

    Shih, Chun-Jen; Lee, Chih-Chien; Chen, Ying-Hao; Biring, Sajal; Kumar, Gautham; Yeh, Tzu-Hung; Sen, Somaditya; Liu, Shun-Wei; Wong, Ken-Tsung

    2018-01-17

    An exciplex forming cohost system is employed to achieve a highly efficient organic light-emitting diode (OLED) with good electroluminescent lifetime. The exciplex is formed at the interfacial contact of a conventional star-shaped carbazole hole-transporting material, 4,4',4″-tris(N-carbazolyl)-triphenylamine (TCTA), and a triazine electron-transporting material, 2,4,6-tris[3-(1H-pyrazol-1-yl)phenyl]-1,3,5-triazine (3P-T2T). The excellent combination of TCTA and 3P-T2T is applied as the cohost of a common green phosphorescent emitter with almost zero energy loss. When Ir(ppy) 2 (acac) is dispersed in such exciplex cohost system, OLED device with maximum external quantum efficiency of 29.6%, the ultrahigh power efficiency of 147.3 lm/W, and current efficiency of 107 cd/A were successfully achieved. More importantly, the OLED device showed a low-efficiency roll-off and an operational lifetime (τ 80 ) of ∼1020 min with the initial brightness of 2000 cd/m 2 , which is 56 times longer than the reference device. The significant difference of device stability was attributed to the degradation of exciplex system for energy transfer process, which was investigated by the photoluminescence aging measurement at room temperature and 100 K, respectively.

  20. Optical and electrical effects of plasmonic nanoparticles in high-efficiency hybrid solar cells.

    Science.gov (United States)

    Fu, Wei-Fei; Chen, Xiaoqiang; Yang, Xi; Wang, Ling; Shi, Ye; Shi, Minmin; Li, Han-Ying; Jen, Alex K-Y; Chen, Jun-Wu; Cao, Yong; Chen, Hong-Zheng

    2013-10-28

    Plasmonics have been proven to be an effective way to harness more incident light to achieve high efficiency in photovoltaic devices. Herein, we explore the possibility that plasmonics can be utilized to enhance light trapping and power conversion efficiency (PCE) for polymer-quantum dot (QD) hybrid solar cells (HSCs). Based on a low band-gap polymer poly[2,6-(4,4-bis-(2-ethylhexyl)-4H-cyclopenta[2,1-b;3,4-b']-dithiophene)-alt-4,7-(2,1,3-benzothiadiazole)] (PCPDTBT) and a CdSe QD bulk-heterojunction (BHJ) system, gold nanoparticles were doped at different locations of the devices. Successfully, an improved PCE of 3.20 ± 0.22% and 3.16 ± 0.15% was achieved by doping the hole transporting layer and the active layer, respectively, which are among the highest values reported for CdSe QD based HSCs. A detailed study of processing, characterization, microscopy, and device fabrication is conducted to understand the underlying mechanism for the enhanced device performance. The success of this work provides a simple and generally applicable approach to enhance light harnessing of polymer-QD hybrid solar cells.