This paper describes examination of the high temperature fatigue lives on gas turbine materials for combustors using a plane bending fatigue testing method It is important to examine how in-service operation affects the high temperature fatigue lives on combustor materials to maintain the integrity of gas turbines. Gas turbine combustors for power generation are consisted of thin plates by Ni-base superalloys. Therefore, It could be difficult to evaluate fatigue life using a uniaxial tension-compression testing method by round bar specimens Thin plate specimens were prepared from inner side plates of the combustors. The plane bending fatigue tests using thin plate specimens were conducted at high temperature. Low-cycle fatigue lives in various regions of the combustors at 850℃ were obtained. The plane bending fatigue testing method could be a useful tool to evaluate the degradation of combustor materials in-service.

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The new huge steel structure to cover the entire Chernobyl Reactor Building completed for the first stage and we visited Chernobyl last December We visited also the hospital for all the Ukraine people who got the radiation from Chernobyl. We are impressed by the city where the hospital locates. There were a lot of workers required for Chernobyl recovery. They needed their resident houses. They decided to make the dreamy city for their residence and then constructed Slavutich city within two years where 24,700 people are living right now by free of charge. There are 11 story apartments and the independent houses with the garden where the people with three children can live. In Fukushima after two years from the bad accident the people are living in the tentative cold houses. There are only the bad news in Fukushima and I strongly insist to make the dreamy city in Fukushima to remember the smiles for the people.

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Construction of the New Safety Confinement (NSC) for the Chernobyl unit 4 started 2010,after about 25years of Chernobyl accident and will complete summer of 2015 This project is being conducted by assistance of EU, USA and other countries including Japan. NSC can cover the whole facility of unit 4, and is installed various components or tools including big bridge crane for decommissioning unit 4 and has durability over 100 years In addition to construction of NSC, various activities for preparing the decommissioning including developing the technology of monitoring the inside of destructive building and remote access technologies. The spent fuel storage facility and waste proposal facilities are also constructed. These activities include many valuable information about how to smoothly conduct the decommissioning and it would be important to learn the above activities in conducting the post-processing activities on the Fukushima-Danchi accident successfully.

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Fukushima Daiichi NPP accident will be terminated, if sufficient care of recovery for heart of people, economy and enviroment leads to happy Fukushima. It might be taken more than 20 yesrs or more The oversea NPP investigation group in the study comittee for safety regulatory of NPP in PES division in JSME visited Chernobyl NPP, Ministry of Emergencies, National Institute for Strategic Studies under the President of Ukraine, Chornobyl Center, Slavutych, Research Center for Radiation Medicine of the National Academy of Medical Sciences of Ukraine, National University of Life and Environmental Science of Ukraine, Institute for Safety Problems of Nuclear Power Plants and Chornobyl Museum. The investigation of bases of their new technology for deep LRW cleaning of Fukushima genesis from the whole range of radionuclides, including uranium and transuranic elements, organic impurities and simultaneous concentration of radioactive components in a small volume. The recovery of eivironment and care of heart of people were good in Ukuraina The lessons derived from the accident, we can decide what we should do.

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To avoid the severe energy crises estimated at 2050s and to face the growing global climate crises, This paper proposes to enlarge Nuclear energy to supply enough surplus power to yield Hydrogen for multi-purpose (C_1 Chemical with Blast Furnace Gasification in ironworks, Refinery, Petrochemical, Fuel cell) and to replace fuel with Heat Pump & EV and utilize Small Modular Reactor efficiently with illustrating some examples Example A: Small Modular Reactor co-generate heat & power to dry Victoria-lignite in Australia and to resolve it into Char, water and tar, this Char is useful for C_1 Chemical in Japan Example B: Small Modular Reactor co-generate heat & power to extract Methane of Methane-Hydrate well in the bottom of the sea.

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This paper describes an overview of Fukushima accident, lessons learned from it and measures to enhance safety reflecting the lessons The accident and response actions are analyzed to extract lessons. Based on the lessons three basic policies to enhance safety are discussed Firstly with considerations of multiple failures defense in depth should be enhanced by applying more diverse safety measures. Secondly a phased approach should be considered in choosing mitigation measures considering timing of the response actions and required reliabilities. Lastly performance requirements should be clarified for a containment vessel and its support systems after core damage. Specific safety measures are designed based on these policies and applied at Kashiwazaki Kariwa Nuclear Power Station.

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TOSHIBA has been carried tests to evaluate performance of the filtered vent system. In order to apply several parameters and functions, test facility is useful and has much flexibility The filtered vent system has 2 functions, one is scrubbing in water and the other is metal filter. Test results show a good performance We will introduce a outline of the filtered vent system examination.

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In the Tokyo Electric Power Company's Fukushima Daiichi nuclear power plant accident which results from the earthquake in the Tohoku district Pacific Ocean and the tsunami accompanying it, which occurred on March 11, 2011, a severe accident occurred, leading to reactor core damage and containment failure. As a result, a lot of radioactive materials were released into the environment from the plant. Strengthening of the counter measures against containment failure including installation of a filtered venting system enables it to reduce the probability of these accidents as much as possible.

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This paper describes how to write a manuscript of the 18th PES Proceedings. In the Fukushima Daiichi Nuclear Power Plant accident, a great deal of radioactive material was released to surrounding environment After the accident, the Filtered Containment Venting System (FCVS) that can remove radioactive material from steam in containment vessel has attracted a great deal of attentions. However, there is few knowledge of filtered vent in Japan because almost filtered vent were developed in Europe after Chernobyl nuclear power plant accident. Therefore, our purpose is getting the knowledge of filtered vent through experiments that simulate various filter vents in Europe. Also using the knowledge gotten through experiment, we aim at developing high efficiency filtered containment venting system using zeolite.

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Mitsubishi Heavy Industries, Ltd. (MHI) has been carrying out the evaluation of the diffusion of the radioactive material using our wind tunnel facilities before as the environmental impact assessment of Nuclear Power Station in Japan. Further, we are tackling development of the analysis code adapting the technology of abundant air current analyses and diffusion analyses, and dose projection analysis. On the other hand, we also have been coping positively with the support of Nuclear Comprehensive Emergency Drills/Exercises which was started seriously after Tokai-mura JCO Criticality Accident occurred on September 30, 1999. We also have abundant experiences in design, manufacture, and construction of nuclear facilities including PWR Power Plants since Mihama Nuclear Plant Unit 1 of Kansai Electric Power which started its commercial operation on November 28, 1970. By utilizing these experiences, outcomes, and knowledge, we have developed the system called MEASURES aiming at practical use in Nuclear Power Stations. In this presentation, the concept and basic system configuration of MEASURES, advanced features of MEASURES developed on the basis of discussions regarding Fukushima events which were occurred on March 11th, 2011, and the post evaluation results of Fukushima events will be reported.

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Shatter zone called "D-l" lies under the reactor building of Tsuruga Power Station (Tsuruga PS) Unit.2. The Japan Atomic Power Company(JAPC) has been investigating the D-l shatter zone in several ways (Overlying Strata Analysis Method, Tephra Analysis Method etc.) and evaluating that the D-l shatter zone would not be an active fault which should be taken into account in the seismic design, so far Additionally, JAPC have numerically analyzed how the shatter zones would be affected in case of the Urasoko fault moves using elasticity theory of dislocation method and Two Dimensional Finite Element Method.

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Information concerning the spatial distribution of debri in the containment vessels is of considerable importance in the decommission process of Fukushima Dai-ichi nuclear power plants. Since the cross-sectional area of the debri jet discharged from a reactor vessel may have great impact on the spatial distribution of debri, experiments of liquid jet were carried out in the present work Particular attention was paid to the effects of the nozzle shape and the back pressure In addition, spreading characteristics of debri on the pedestal floor was investigated through numerical simulation using the SAMPSON code.

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It is the important issue to fill up each nuclear reactor/containment vessel with water and to take out debris of damaged fuel from them for decommissioning of Fukushima Daiichi nuclear power plants. It is necessary to detect the debris and water leaks at a nuclear reactor/containment vessel for the purpose However, the method is not completely developed in the present stage. Accordingly, we have developed a method for detecting debris and water leaks at a nuclear reactor/containment vessel by flow visualization Experiments of the flow visualization were conducted using two types of water tanks An optical fiber and a collimator lens were employed for modifying a straight laser beam into a sheet projection Some visualized images were obtained through the experiments. Particle Image Velocimetry, i.e. PIV, analysis was applied to the images for quantitative flow rate analysis. Consequently, it is considered that the flow visualization method has a possibility for the practical use.

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This paper describes defects which caused the meltdown in Fukushima Dai Ichi No.1 nuclear power plant The valve-rod in a Primary Loop Recirculation was broken by the Delayed Fracture.

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Due to the increase of aged nuclear reactors, reduction of radioactive wastes is expected and cutting technology for thick structure would be necessary. Thermal cutting technology would be convenient for cutting thick materials, but generation of radioactive fume is one of the problems. A water jet-guided laser cutting is one of the suitable technologies for this application, because radioactive fume would be confined in the water and doze level won't be increased. However, this technology was developed for precision machining like dicing and slotting of silicon wafers, it is difficult to cut thick materials In this study, cutting technology for thick material with a water jet-guided laser was discussed Phenomenon during cutting thick stainless steel was observed by using high speed camera and optimum conditions for both water jet and laser cutting were derived. Finally, 50mm thick stainless steel plate was successfully cut by using this technology.

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For better energy policy and consensus building, we try to establish a scientific method to keep the basis of judgment clearly visible. In many cases, objective scientific assessment is mixed up with subjective judgment unintentionally. Thus, the roles of scientific advisors and policy makers are confused Therefore, we propose a quantitative method, with which evidence-based scientific assessment and value-based political judgment are to be clearly separated. The effectiveness of the proposed method is examined by a trial study on prioritization of research and development themes in the energy technology areas of Japan.

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To quantify the risk and impact of CO_2 seepage to the marine ecosystem, the Quantifying and Monitoring Potential Ecosystem Impacts of Geological Carbon Storage project is now undergoing in a bay in Scotland. In advance of the field experiment of this project, we conducted the numerical simulation of CO_2 seepage From this numerical study, we predicted how CO_2 behave in the bay and how the condition of the sea changes.

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Transportation of CO_2 is a key component in the CCS chain for commercial projects, and CO_2 shipping is being reconsidered as an alternative to pipeline transport. The ship-based transport will make it possible to couple CO_2 recovery plant and storage site without being limited to a single sink-source match, and decoupling and moving to another sink can be done with relative ease when necessary. It also removes the pipeline construction and removal activities in coastal zone where the social activities like fishery are often high In this study, the technical feasibility of shuttle-type shipping and offshore operation for CO_2 injection from the ship to the well(s) is demonstrated The main components needed for the proposed system are compression and liquefaction of CO_2, temporary storage at port, offloading, shuttle ship with Dynamic Positioning System and injection equipments onboard, flexible riser pipe whose end is connected with the wellhead on the sea floor, and pickup system at site.

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We experimentally investigated the effect of capillarity and buoyancy on non-wetting phase (NWP) saturation after the drainage. Distributions of the NWP in porous media have been visualized by mean of microtomograhy at a pore-scale. Viscous fingering is caused on the interface when less viscous NWP is displacing viscous WP. In the case of the upward injection, gas saturation is low compared with the upward case, because the fingering is enhanced by buoyancy. In the case of the downward injection, the fingering due to unfavourable viscosity ratio is suppressed by buoyancy. As a result, the high gas saturation is achieved over the wide range of capillaiy number. The combined dimensionless group of Bond number and capillary number is introduced to correlate with the gas saturation Finally, the effect of heterogeneity on gas saturation after drainage process was discussed In the case of parallel structure, the NWP flows through layers with high permeability and with low entrance pressure especially for low capillaiy numbers. Therefore gas saturation is quite low both for upward and downward injections. In the case of serial structure, capillary entrance pressure caused at the interface of discontinuity of pore structure has a strong influence to increase NWP saturation in porous structure before the interface.

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Especially in a bubbly turbulent flow, the dynamical interaction between the bubbles and their surrounding liquid motion is an important factor to decide the flow itself The modulation of the ascent bubble motion from 2D (i.e. zigzag motion) to 3D is enhanced in the turbulence field We discuss how the dynamical gas-liquid interaction triggers the enhancement of the modulation of the bubble motion. A single oblate ellipsoidal bubble of 2.9 mm equivalent diameter was launched into an oscillating-grid decaying turbulence; its surrounding liquid-phase motion was measured by using PIV/LIF and its wake was visualized by using LIF/HPTS. Simultaneously, the bubble center-gravity motion and surface oscillation were captured by using infrared shadow-image technique. Compared the results obtained m the decaying turbulence with those in the stagnant water, we discussed the relationship between the bubble-liquid interactions and the modulation of transition of the bubble motion.

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Bubbly flows are used in various industrial plants: e.g. fired power plants, oil plants. Elucidating the flow structures contributes to promoting energy efficiency and energy saving of the plants. The main purpose of this study is to clarify the relationship among bubble swarms, liquid-phase motion and the dissolved CO_2 concentration transportation in a bubble column. For this particular purpose, we simultaneously measured time-series void fractions, local CO_2 concentrations and liquid-phase velocities, by using a newly developed optical fiber probe (POFP) and a laser Doppler velocimeter (LDV). We calculated the spatial scales of the bubble swarms and liquid-phase motion, based on the thinking of the integral length scale As a result, the spatial scales of the bubble swarms and liquid-phase motion were different by height in the bubble column. Moreover, we discussed the relationship between the flow structures and CO_2 concentration transportation by using cross correlation coefficient of the dissolved CO_2 concentration.

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We have investigated flow behaviour around a moving hydrofoil beneath an air-water interface in order to optimize the hydrofoil facility of bubble generation for drag reduction of ship. Experimental results of flow visualization show that the deformation characteristics of the air-water interface depend on the occurrence of the flow separation over the hydrofoil. The attachment of the flaps to the hydrofoils causes significant deformation of the air-water interface in the downstream, which induces wave breaking and results effective bubble generation. On the other hand, we could not observe the effective bubble generation by the vortex generators because the magnitude of the free surface deformation becomes small due to turbulent flow.

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We have developed the successful technique to improve the temperature exchange efficiency at the heat exchange region by absorbing thermal radiation energy emitting from CO_2 in the combustion exhaust gas. The electro-magnetic radiant materials as the absorption materials are applied at the inner surface of combustion chamber (CO_2 Spectrum Heat Absorption Technique). In order to check how robust our results are, the verification tests on the temperature exchange efficiency are carried out by employing the wick diffusion flames and fire tube and flue boilers. The fuels studied are kerosene, ethanol, and methanol for wick diffusion flames and LNG for fire tube and flue boilers. From these results obtained for the study we may predict that the spectrum heat absorption technique is very useful and effective to achieve the high energy saving through the improvement of thermal efficiency on fossil fuel combustion.

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The possible reasons of formation rate decrease of CO_2 hydrate around microscale ice are discussed by taking thermal and dynamic effects into account First, the thermal effect is modeled by numerically integrating the distributions of local temperature rise by the for mation heat. The constructed temperature model is implemented to the original formation model and the result shows decrease of formation rate. However, the effect is not as significant as was experimentally observed in the literature Second, dynamics of hydrate membrane is modeled and the relation of expansion pressure and the yield stress is derived. The results shows that the former is much larger than the latter and the dynamic effect is almost negligible.

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CO_2 hydrate formation generates exothermic heat Thus, there is a possibility to warm the sand layers for production of methane hydrate by using the heat. We had experimentally obtained data by flowing CO_2/water emulsion into Toyoura sand In this paper, the number 7 silica sand is used as more realistic sub-seabed sediments. The results showed that temperature rise by some degree centigrade at the tip of the permeation of the emulsion. And the temperature approached gradually to the phase equilibrium of CO_2 hydrate with continuous flow. This shows a possibility of an enhanced recovery using CO_2.

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The purpose of the present study is to develop the prediction models of CO_2 hydrate film thickness for the long run CO_2 storage. In this study, we suggest two models First model can predict CO_2 hydrate film thickness. This model structure is based on two-dimensional CO_2 solubility in CO_2 hydrate generation phase Second model can predict the growth behavior of CO_2 hydrate film This model structure takes into consideration the mass transfer between CO_2 and hydrate film. By using these two prediction models, we can compare predicted film thickness with experimental film thickness under various pressure conditions, and discussed compliance of the prediction models.

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Abstract In this report, numerical analyses of performances of prototype Mg-alloy micro vertical axis wind turbine were conducted It has 3 wings with usual NACA0018 wing section. Typical Reynolds number based on the wind speed and the wing chord length were set around 3.3 × 10^4 with consideration for using as a portable-type micro VAWT system for engineering educations. In such low Reynolds number cases, somewhat different way of design would be required. We also examined a torque variation generated from the wings using 3-D unsteady CFD analysis and compared the results and flow patterns for higher performance in case of such low Reynolds number flow.

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This study carried out CFD analyses to build up a database of aerodynamic characteristics of cambered blades like NACA 2518, NACA 4518, and NACA 6518 in order to use it for performance prediction of vertical axis wind turbines(VAWTs). Dependence of the increase in lift coefficient on the Reynolds number is shown as well as dependence of the decrease in moment coefficient, and the approximate equations for these dependences are proposed. Using the aerodynamic database, performances of virtual small VAWTs with cambered blades were predicted by Blade Element Momentum method. Increase in usual camber extends the power curve toward high tip speed ratio region although the maximum power decreases.

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Computational fluid dynamics (CFD) modeling and experiments have both advantages and disadvantages. Doing both can be complementary, and we can expect more effective understanding of the phenomenon. CFD is generally difficult to obtain reliable results over the wide range when compared with the experiment However, it is possible to obtain useful detailed results in any condition based on verification using the experimental results Moreover, experiments are not necessarily deliver correct results for any arbitrary condition due to limitations of the experimental equipments, the measurement errors and the problems with measurement systems. In this paper, the efficiency of a wind turbine is proposed, and the performance can be compared with the other turbomachineries, which is different from the traditional wind turbine factors, that is, the power coefficient, the torque coefficient, the thrust coefficient and so on. The characteristics of wind turbine are evaluated by combining simple approximate analysis based on wing section, CFD simulations and experimental results.

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This study simulates the flow through the rotor of an open cross-flow type hydraulic turbine by a two-dimensional particle method. The simulation demonstrates that the rotor performance agrees nearly with the measurement and that the flow is successfully analyzed. It is also made clear that the performance deterioration due to the increment of the flow rate is caused by the reduction of the 2nd-stage flow between the rotor blades.

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In future planning pf the city, it is very important to consider the proper intelligent integration of renewable energy sources into the built environment for developing smart cities. This study proposes that the accelerated wind by blowing through buildings is utilized for wind turbine. A building model whose layout is like nozzle is proposed for obtaining the accelerated wind. The wind velocity distribution across the buildings is numerically simulated by commercial CFD software. Wind turbine power output is estimated by the wind velocity distribution simulated by CFD software and the power curve of real commercial wind turbine. For the feasibility check of installing the building model in some area actually, the power energy of wind turbine is investigated by considering the data of wind velocity and wind direction distribution intended for Tsu city as an example.

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When introducing renewable energies, the job-creation effect needs to be considered in addition to stable supply of energy and countermeasures against global warming. In this paper, we estimated the job-creation effect in the life cycle of wind power plants which is expected to be massively introduced into the Hokkaido, the life cycle of wind power generation includes manufacture of a wind turbine, power generation, operation and maintenance. Input-output table analysis is applied for the estimation, and wind power generation sector is newly added to the published version of the Hokkaido input-output table. The life cycle job-creation is estimated to be 1.34 person*year/GWh Of these, 0.57 person*year/GWh are Construction of wind turbine and 0.77 person*year/GWh are wind power generation About 30% of the life cycle job-creation is created outside the Hokkaido.

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To spread the wind power technology, the power fluctuation risk of wind power plants, i.e.a risk of frequent and large reduction in the output caused by time-varying wind speeds, need to be decreased. Among measures against the risk, the geographical distribution of wind power plants needs to be examined first because additional facilities, such as backup thermal power plants or electricity storages, are not required. This study analyzes the risk reduction effect of geographically distributing wind power plants among the regions within Hokkaido. The mean-CVaR (Conditional Value at Risk) model is adopted to estimate optimum geographical distribution of the plants. We found that the geographical distribution can largely decrease the power fluctuation risk. Such a result indicates that the Hokkaido has enough variety of climates to largely decrease the power fluctuation risk of wind power plants by domestic geographical distribution.

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This paper describes on the energy saving using ocean, and power management using ship at time of the disaster. Yokohama Green Valley is a concept for purpose of CO2 reduction and revitalization of the economy, using the city coastal area as a model In order to realize this concept model, we performed experiment at Yokohama Hakkeijima. Experiments were performed following concretely 1 Introduction of seawater heat pump. 2. Power supply from the ship in emergency. 3. Visualization of power. The seawater heat pump, we have energy-saving 20% cut off of power. We found that the power of ship to land is an effective method in emergency. In energy saving by smart meters, we found that there is an economic benefit to reduce the basic charge of power.

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Co-generation systems and district heating and cooling have been applied to urban areas for achieving a low-carbon society. However, CO2 emissions from operations division including commercial buildings are still on the increase Hence research of micro grid is conducted as one of the countermeasures for achieving a low_carbon society. In case micro grid is introduced actually, it is facilitated by choosing a region where district heating and cooling was already applied Thus in this report, a combined system composed of micro grid and district heating and cooling was considered. The combined system in this study interconnected 3 commercial-scale utility customers with different electric demands and thermal demands. Annual CO2 emissions in each condition were minimized by using a numerical software GAMS/BARON.

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Promoting utilization of photovoltaic (PV) cell, for residential use has become urgent issue recently. One approach is to use an electrical battery (BT) in the house in order to maximize consuming the electricity generated by the photovoltaic power generator. The energy systems including energy buffer like electrical batteries have a lot of operational flexibility. The mathematical optimization technique is useful for rational energy use The objective of this study is to making operational optimization models considering degradation characteristic of a battery. As a result, the four types of operational optimization models, which consider degradation characteristics caused by battery cycle life, were formulated on the mixed integer linear programming problems. Consequently, it was found that the appropriate optimal operational strategy should be derived from the model including the degradation characteristics on DOD.

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In order to expand the natural energy and increase the energy effectively, the photovoltaic power generation (PV) and electric vehicle (EV) combined system has been proposed. In order to spread the EV, it's necessary to solve some problems which are high energy consumption of air-conditioner, high cost of storage battery and risk aversion of a dead battery. So, Air-conditioning system Integrated Electric Vehicle (ITEV) which has a great possibility to solve the current EV problems has been proposed. In this paper, the authors have studied the introduction effects of ITEV using in the PV & EV combined system which is considered to optimize not only the vehicle but also as s whole energy system in a Smart community. As a result, ITEV can reduce C0_2 emissions by 37% comparing with the current system as the same as EV In addition, ITEV is able to gam the cruising range twice as long as EV with the same battery capacity.

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Silicon nanocrystals (Si NCs) have unique optical and electronic properties that are advantageous for semiconductor device applications and here their application to photovoltaics is examined. Freestanding Si NCs were synthesized by a non-thermal plasma using silicon tetrachloride (S1CI_4). Blended solutions of Si NCs and p-type semiconductor polymer (P3HT) were fabricated by spin-casting to form bulk-hetrojunction devices. The weight fraction of Si NCs in P3HT was found to greatly impact the device performance. As the weight fraction increases up to 50 wt%, the short-circuit current dramatically increases, while the open-circuit voltage and fill factor do not change significantly. The improvement in device performance is attributed to increased probability of excitons in P3HT finding an interface before recombination and an enhancement in the conversion of wavelengths where P3HT is a poor photovoltaic material.

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Thermal efficiency of marine engine in a small fishing boat is about 40%, more then half of the energy is discarded. As an example of energy-saving measures of fishing boats, there is a exhaust heat power generation for effective use of recovered energy to be treated as exhaust heat. In this study, the performance of exhaust heat power generation system is evaluated using HFC-245fa as a working fluid for small fishing boats, as well as to clarify the characteristics and performance evaluation, the results are compared with the results using propane and ammonia.

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This study aims to develop a heating assist system for liquid tanks by using shallow geothermal energy via a new type of heat pipe named Bubble-Actuated Circulating Heat pipe (BACH). In this system, BACH transports heat from shallow underground (temperature remains constant at around 15 ℃ in Fukui) to the liquid of caustic soda solution (49 wt%, freezing point is about 5 ℃) preserved in the tank. From a previous simplified small-scale experiment, we concluded that BACH could warm the liquid to some extent in winter In this report, experimental results of field tests are demonstrated where 10 m^3 tank equipped with an electric heater as an auxiliary heater was tested and five BACHs were installed. As a result, this system could warm the liquid at about 7 ℃ only by BACH without electricity.

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A Low-grade Thermal Energy Conversion (LTEC) which is Geothermal, Wasted Energy, Ocean Thermal Energy, is refocused on as one of the renewable energy to solve the global warming and the energy problem. The heat source temperature in LTEC system is lower than that in the conventional thermal or nuclear power systems, and subsequently The thermal efficiency of cycle is theoretically small Therefore it is necessary to enhance the thermal efficiency of the LTEC system. The Multi-Stage cycle was proposed aiming at optimizing the power output from low-temperature heat sources such as geothermal of waste heat. This paper presents the maximum power of Multi-Stage cycle that has independent equipment respectively. Improvement in the system performance is achieved by decreasing the irreversible losses in the heat exchangers. The maximum power obtained from high and low temperature fluids is decided by warm and cold source temperatures, flow rates, number of stage.

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A Low-grade Thermal Energy Conversion (LTEC) is refocused as one of the renewable energy. For the LTEC and Refrigerator/Heat Pump, it is very important to enhance the heat transfer on heat exchanger though the available temperature deference is smaller than conventional thermal system. In last study, by using micro fabrication surface on plate evaporator, heat transfer coefficient of HFC245fa is enhanced compared with normal surface plate evaporator. In this paper, the experimental performance test as evaporator is evaluated on comparison with HFC245fa and HFC 134a The results show the boiling heat transfer coefficient of HFC 134a was larger than that of HFC245fa Heat transfer coefficient of these working fluids is estimated using Lockhart-Martinelli parameter.

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REBCO superconductors are promising for coil applications such as MRI, NMR and Superconducting Energy Storage System One apparent shortcoming of REBCO conductor coils is an extremely low fraction of conductor in the coil winding, as the REBCO conductor is as thin as 100-150 μm, comparable to the insulation thickness. If we wish to achieve high overall current densities for REBCO coils, the insulation thickness on REBCO conductor must be substantially reduced. Therefore, we have developed a 4 μm ultra-thin polyimide insulation coating by electro-deposition, which is 10 fold-thinner than conventional insulations on REBCO conductors. The fraction of REBCO conductor in the coil winding manufactured by this novel conductor becomes as high as 90%. A coil design demonstrates that if we use the REBCO conductors with 4 μm-thick polyimide coating instead of the conventional insulated conductors, we can decrease the amount of conductors by -80%.

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This study is to investigate of a utilization of thermal energy by slight temperature difference. An experiment has been carried out using the Peltier elements. We focused on an electric power generation system using thermal energy of hot spring water and Seebeck effect of thermoelectric conversion elements. In order to set a suitable temperature difference on both sides of the Peltier element, an apparatus consists of a rubber heater and a water cooled jacket. This paper described a relationship between the electric power and the temperature difference of the Peltier element. This system will be applied to the continuous power generation and to the LED lighting for 24hours.

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REBCO high temperature superconductors are promising for various superconducting coil systems such as MRI, NMR and Superconducting Energy Storage Systems. However, REBCO coils sometimes shows thermal runaway, resulting in meltdown of the coil in the worst case. In this paper, we investigate the effect of thermal grid method, in which heat channel of high thermal conductive metal are installed in the coil winding, on temperature increase of the REBCO coil due to thermal runaway. We demonstrate that there is a time interval prior to thermal runaway, in which the normal conductive part shrinks if the coil current dump starts.

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Economical CO_2 reduction will be possible to use the combination system of photovoltaic power generation (PV) and Electric vehicles (EV). In order to spread the EV, it's necessary to solve some problems which are high energy consumption of air-conditioner, high cost of storage battery and risk aversion of a dead battery. In this paper, the authors have proposed and studied an Integrated Electric Vehicle with air-conditioning system (ITEV) which is installed a small engine to supply the power of air-conditioner. As a result, the engine power requires 120cc or less displacement which is smaller than conventional PHV (plug-in hybrid Vehicle) and possible to be a co-generation system to drive air-conditioner. So, ITEV is proposed a practicable solution of the current EV.

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CRGT (Chemically Recuperated Gas Turbine) cogeneration systems can save fuel consumption and CO_2 emission by chemical recuperation of exhaust heat using endothermic reaction of natural gas steam reforming This study aims to quantify the effect of CRGT modifying an existing STIG (Steam Injected Gas Turbine) cogeneration system in an actual industrial plant and proposes an operating method to reduce fuel consumption with avoiding catalyst deactivation of the reformer in CRGTs. Around one hundred PFDs (Process Flow Diagram) of the existing STIG system was built on a process simulator and modified by addition of the equilibrium reactor including reactions of city gas steam reforming and water gas shift. Simulation results indicate that the CRGT can save fuel consumption by around 5% in comparison with the existing system even m partial load operations and also that use of all excess steam by the reformer can increases the power generation efficiency of the CRGT, while the steam injection flow rate should be minimized in the STIG to obtain a higher power generation efficiency.

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Residential fiiel cell cogeneration of SOFC has been evaluated using exergy approach. The exergy can be evaluated the exergy loss based on the increase of entropy. The exergy loss of a water independent type SOFC mainly occurred at the preheater and afterburner. These losses are recovered when electricity efficiency is improved by the increase in fuel utilization ratio of the cell stack. The anode gas recirculation SOFC can also recover another heat transfer loss at the preheater due to the avoidance of the water evaporation. Furthermore, the system exergy efficiency is defined, and the cogeneration operation data for a year is simulated in order to evaluate the energy saving effect of SOFC cogeneration. It is found that the system exergy efficiency can quantity the energy saving and electricity saving effect independently. The results also indicate that the increase in the rated power output and the reverse power flow is effective to derive the energy saving effect of the SOFC over the electricity efficiency of 55%.

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The steam compressors are usually developed for the purpose of large size and special VRC (vapor re-compression) application. However, it seems to have a considerable ripple effect on the various purposes if the small size and high performance steam compressor are practical use. In this study, the authors suggest the two-phase compression process models which are based on the various assumptions. In addition, an experimental set-up which uses 7.5kW - wing type compressor is made to validate calculation results and enabled to confirm reduced discharge temperature and effect of compression work reduction. An effect of two-phase compression of the steam is reported by comparing calculation results with experimental results.

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It is well known that the wetness of steam flow sometimes causes measurement errors of the steam flow meter. However, it is difficult to clarify the error and steam wetness quantitatively in actual plants and factories. Therefore, we have started steam flow rate measurement experiments to clarify the measurement error caused by the wetness of steam flow m a plant and a factory. As a result of the study, we have suggested the correction method of the measurement error for 3 flow meters. Then, m this study, we have tried to estimate the steam wetness in the wet steam flow with multi flow meter installation method. The measured flow rate in the wet steam flow is dependent on the type of flow meter and different from each other. So, we applied these characteristics and developed the evaluation analysis method to evaluate the wetness.

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