The installation of wind power generation is progressing globally to prevent exhaustion of resources and global warming. If the output fluctuation of the wind turbine is suppressed using the storage battery, total installation cost may become expensive. In this study, authors propose to utilize the inertial energy of windmill to suppress the output power fluctuations. The proposed control reduces the rotating speed of a variable speed wind turbine to inject excessive power to the grid by a vector control of utility interactive converter. Therefore, the output power of the wind power generation can be boosted by the inertial energy of the windmill. When two wind power generators are connected in parallel, interchange of the inertial energy between the windmills can be considered and, therefore, the total output power of the two wind power generators can be smoothed during a short period. In this paper, it is confirmed that the fluctuation can be suppressed by the proposed method as compared with the case where the wind power generators are equipped with no more than the traditional MPPT control.

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The objective of this research is to design an operator-based nonlinear control system for thermoelectric generation so that the generated energy becomes maximum within determined range of time. Electric current control using DC-DC converter is necessary to achieve the maximum condition. Desired current is calculated from evaluation function and heat transfer model including the thermoelectric generator. The designed control system is verified by numerical simulations and experiment.

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In order to utilize the power output of photovoltaic (PV) power generation as much as possible in an electric power system, proper unit commitment (UC) scheduling based on an accurate and reliable forecasting of PV power output is essentially important. This study based on a computational simulation demonstrates the effect of forecast update on the improvement of UC scheduling as follows. In a large demand case, the cost is reduced by about 2 % by 20% forecast improvement when the update is available early in the morning. In a small demand case, the cost reduction by the forecast improvement is limited due to smaller flexibility of generators.

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Under the Paris Agreement, Japan promises reducing 26 % from greenhouse gas emissions in 2013 by 2030. We have proposed a concept of Cluster Energy Management System, CEMS, which can design a highly saving-energy network based on demand simulation of communities consisting various different residents. As an example of CEMS designing a good thermal and electricity demand-balance among a network of residential houses, commercial and nursing facilities is introduced. The network can use almost whole exhaust heat from distributed power plant such as fuel cell with solar power and thermal utilization. We can simulated saving about 40 % in prime-energy consumption and about 45 % reduction of CO2 emission by designing an example case of the CEMS, which combines fuel cells and electric vehicles in a community, where 200 families including elderly people are living. We concluded that it would be possible to reduce primary energy consumption and CO2 emission by nearly a half amount or more by introducing the CEMS.

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The presented study covers concepts for residential heat grids, including power-to-heat solutions and shared storage approach, based on a realistic large scale infrastructure. It targets the investigation of advanced solutions for a heat revolution within the frame of energy revolution and climate targets 2050. Multivalent heating systems are implemented and compared in a fully automated neighborhood grid, consisting of residential buildings, a switchable local heat grid matrix and instrumentation for widespread energy and climate measurements. The neighborhood grid is built within the project Living Lab Energy Campus is connected to the large project Energy Lab 2.0 infrastructure, which allows upscaling of data in the range of several MW via physical simulations and serves as fully controllable supply grid.

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A palisaded heat exchanger combined with plastic pipes was newly developed and applied for heat recovery system from hot springs. The heat exchanger was easily formed by thermal fusion bonding, which gave high heat transfer area to installation volume. The heat exchanger can be used to recover heat from corrosive hot spring water and waste water with low pH solutions or many suspended solids, although the overall heat transmission coefficients were comparatively low 65－73 W/(m2・K). Polypropylene random copolymer samples derived from the plastic pipes exhibited high tensile yield strengths even after soaking for 2-8 weeks in hot spring water.

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In order to realize energy saving at university campus, it is necessary to utilize renewable and unutilezed energy existing in the campus. In this paper, the performance of air conditioning system that uses pond water as heat source for heat pump (HP) is investigated using system simulation. Simulation results show that primary energy consumption of the HP using pond water is reduced compared to the system with air-source heat pump especially in the summer and winter when outdoor air conditions are severe. However, the energy consumption of the additional pumps for water-source system has increased.

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Total nominal power of solar photovoltaics (PV) worldwide installed in 2050 will reach more than 4 TW. As assuming 20 % PV efficiency of the panel, the rest of 80 % solar radiation would be the exhaust heat from the PV panels at about temperature of (ambient + 40℃) on fine day. Therefore, PV panel would be better to be kept at lower temperature and the panel could be used for providing not only electricity but also thermal energy. We are developing a photovoltaic/thermal (PVT) panel by coupling with decompression boiling for collecting thermal energy, which can control the temperature of inside air in the panel. This report provides the current thermal and PV performances of the proposed PVT panel, which can keep the air temperature inside the panel at the similar temperature of building walls around the solar-panel, while providing warm water about 40℃ through a year.

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Temperature of urban areas has increased since about 100 years ago. It would be needed to develop a new urban device to compensate artificial surface of urban areas by cooling air like leaves of plants. We have applied porous ceramics to a new concept of the cooling device, which can work as leaves of plants. It is a transpiration cooling system. We have already developed a testing device for confirming the thermal performance aiming 2 kW cooling capacity using porous ceramics and confirmed that the cooling ability has already exceeded 2 kW in intermediate seasons and the exhaust-air temperature is lower than ambient temperature in summer. By replacing out-door unit of small-capacity cooling tower or out-door unit of cooling devices, the proposed cooling system can create the non-exhaust heat thermal systems of refrigerating, air-cooling devices, power generator, and PVT solar panels etc.

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We are developing solar and ground assisted hybrid solar heat pump (HP) systems for DHW supply. There are various operating modes in the system and for better overall system efficiency, timing of switching between modes is necessary. In this paper, a detailed control strategy in which starting condition of HP, heat source selection of HP and maintenance of constant hot water supply during an operational day to a general house in Japan has been discussed. For improving efficiency of HP, we are controlling hot water flow rate also. The system is controlled via logical programming. And one-day experiment has been discussed.

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We developed an energy saving control valve which can measure and control flow rate. Energy consumption of each air handling unit (AHU) can be also figured out from flow rate and temperature measured by this control valve. In this report, we introduce the method of energy saving for building HVAC systems using the control valve.

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The effect of adsorption temperature (20ºC; 25ºC) and switching time for adsorption and desorption processes of 60:60 min, 60:90 min, 60:120 min was experimentally investigated on adsorption dehumidification system. It was performed to examine the performance index and moisture adsorbed ability. We found that performance index and moisture adsorbed decreased with the increase of adsorption temperature. While the increase of switching time increases the moisture adsorbed. On the contrary, the performance index increased up to switching time 60:90 min and decreased afterwards. The highest performance index and moisture adsorbed were 0.75 and 900 g/h, respectively.

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In data centers, as there are many servers with high load density, power consumption at data centers becomes large for operation of server itself and air conditioning. In this research, energy performance of economizer system and free cooling are examined. In addition, hot aisle containment which separate the high temperature exhaust air from server and the supply air from air handling unit was proposed in order to maximize efficiency of air conditioning by preventing recirculation of the high temperature exhaust air. Then it was shown that economizer, free cooling and hot aisle containment are effective to reduce energy consumption of server room by simulation.

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This paper discusses numerical solution of conjugate natural convection heat transfer problem using local radial basis function meshless method. Temperature difference is assumed small enough so that the Boussinesq approximation holds. Artificial compressibility method is used to couple the pressure to the continuity equation. The meshless method requires only a set of nodes, which is distributed in spatial domain. The semi algebraic equations is integrated using the second order Runge-Kutta. The numerical results are compared with three benchmark solutions and the results provide a good agreement.

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Industrial development and application of new methods require extensive studies for getting main goals in manufacturing to minimize production, cost, energy, and resources along with improving the function. In this way, a cutting fluid plays an important role for extending tool life of the cutting tool. Because of this reason, the use of the cutting fluid has to have the proper coolant properties for decreasing cutting temperature and friction coefficient in machining processes. An experimental study is performed for investigating the cooling properties of Al2O3(aluminium oxide) nanofluid with Minimum Quantity Lubrication (MQL) method as the cutting fluid in the machining process. For evaluating the cooling properties of cutting fluid, friction coefficient has been measured by using Pin on Disk machining (ASTM G99). The Pin and Disk are made from carbide drill MWS1130LB and carbon steel SS400, respectively. The MQL technique with using nanofluids in the nanoparticle concentration of 1.2 vol. % and conventional cutting fluid or C5 coolant were tested at a volumetric rate of 250 ml/h and 15 liters/min, respectively. As a result, the observed nanofluid has the best performance for decreasing friction coefficient as 36% on 1000 rpm. However, the coolant properties of C5 coolant are better that Al2O3 nanofluid. It is due to the volume concentration of nanofluid is very high, so the performance of the fluid decreases.

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In recent years, in Southeast Asia and the Middle East, large scale buildings have been constructed along with economic development. On the environmental and facility design of those buildings, energy consumption prediction must be performed in detail. It is necessary to grasp the meteorological conditions in the place where the buildings are constructed. Among the meteorological data, director diffuse radiation is separated from global irradiance generally. However, separation models were developed with the data in middle or high latitude regions. Therefore, we have measured meteorological data in low latitude region, and verified the applicability of the models with the data.

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Enhanced tube by employing double-sided delta wing vortex generator with alternate axes (DW-AA) was investigated　to observe thermal-hydraulic performance in the form of Nusselt number (Nu) and friction factor (f). DW-AA was examined for a given wing-width ratio (wr) of 0.47 and 0.63 with varied Reynolds number (Re) of 5,300 up to 14,500. A sophisticated performance was shown by the present configuration which revealed a high Nu and thermal performance (ƞ) with a reasonable increase of f among of all cases. The highest ƞ was in the value of 1.33. Additionally, a high value of wr offered the highest performance.

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We propose a couple of assessment-indexes on energy utilization from two viewpoints of reasonable consumption of energy resource and less environmental thermal-load. The exergy quantity in a demand, AD, is defined as a basis of the new indexes. For the assessment of energy resource, we consider the exergy quantity in consumed energy resource, AR, and propose an index of AR /AD as an exergy-balance-ratio, EBR. The absolute value of EBR is always greater than unity and the EBR being unity is the ideal system. In addition, we also consider the exergy quantity in exhaust heat, AE. We can evaluate the environmental-thermal-load from the whole system by using a ratio of (AE + AD) /AD, which we call the index as an exhaust-exergy-ratio, EER. In case of the EER being unity is no environmental thermal load from the supply system. We could judge the best system by selecting both of EBR and EER to be closest to unity, respectively. The combination of the new indexes would be a useful tool to develop or select an environmentally better system. The quantitative assessment for various thermal devices for air heating will be shown as an example.

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In this work, the effects of climate change on district heating and cooling when the average global temperature rises by 4 °C were assessed by simulation, and adaptation measures toward mitigating these effects were considered. The thermal demand pattern was found to vary with climate change, impacting energy consumption, the economy, and the environment. The following adaptation measures were investigated: seawater thermal cooling (for minimizing the increase in exhaust heat quantity) and the use of heat storage systems (for minimizing the increase in peak load of cold water).

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Employing a CCHP system at the place of consumption is a method for optimizing energy consumption. The CCHP system generates the required electrical energy by using the prime mover, and recovers the lost heat to provide energy for heating and cooling. In this paper, a CCHP system is examined in different modes for residential buildings in Tehran climate. An evaluation of the CCHP system is carried out based on the primary energy saving and carbon dioxide emissions reduction criteria. The results show that use of CCHP system in the residential building reduces energy consumption and carbon dioxide emission. The values of evaluation criteria in the thermal demand management are higher than those of electrical demand management. The CCHP system achieves the best results based on thermal demand management and use of combination of electric and absorption chillers for cooling. The best achievement is reduction of 53% in energy consumption and 64% in carbon dioxide emission compared to a conventional system.

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There are combined cooling, heat and power supply systems (CCHP) as a method of efficient use of energy. In this research, we focus on gas engines among equipments. Gas engines for power generation have two types as high speed type and middle speed type, and maintenance is the most important factor among those characteristics. The purpose of this research is to investigate the type composition at the time of installing a plurality of gas engines and the maintenance of each type, and to evaluate the technical selection by comparing various combinations from the economic point of view. Temporary demand for this time is just 1 year, and 3 units of 4000 kW class gas engine are installed. The configuration of gas engine is mixed with high and middle speed types. As a result of optimization, engine’s operation hour was controlled as unbalanced even with the same types, and there was the case that controlled to limit the operation so as not to have latter stage of maintenance. As the result, a combination of the two types was recognized better than the systems with one type.

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With the development of modern technology, a number of domains, such as agriculture and forestry, readily employ infrared drones. But the application of infrared drones in the field of building industry is still a rarity. In the past two years, some teams have carried out the related researches for infrared drones to survey building thermography, these researches are valuable. In order to promote the development of this research in China, this paper is going to build a procedure of infrared drones in the building industry of China based on a literature research and a series of actual flights. The procedures will be concentrated on the flight stages of using infrared drones and be proposed problems and notices that will be encountered in different stages, in order to guide a completion of a successful infrared detection flight mission. This paper will also give some reflections and suggestions from practical flight by using this procedure. we contribute to the discussion to use infrared drones in the building domain.

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Measurements, questionnaires, and interviews were conducted in a daytime care facility for the elderly that was equipped with a cold-water circulation type of snow cooling systems (SCS) and an air conditioning system (ACS) in Niigata, Japan. Even though small differences were measured in a thermal environment when SCS and ACS were operated, the elderly felt more comfortable in the SCS environment than in the ACS environment. In contrast, the care staff preferred the ACS environment because they felt cool and comfortable in that environment. Moreover, using SCS was difficult to control and maintain a stable temperature owing to a variation in the conditions of the melting snow.

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An aquaponics system combined with open culture and photovoltaic system adapting to arid region has been developed for sustainable food production. The demonstration test on the aquaponics system has been conducted to investigate the technical feasibility by utilizing a small-scale aquaponics system built in the farm field of Tottori University in Tottori, Japan. In order to set the system in impoverished arid region without electricity, the amount of electric power generation by photovoltaic system was predicted by using the typical calculation model and measured solar radiation, to facilitate the calculation about a suitable scale of photovoltaic system.

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The high temperature mechanical behaviors of SiO2-based cores for the directional solidification of turbine hollow blades were investigated. Isothermal uniaxial compression tests of ceramic core samples were conducted on a Gleeble-1500D mechanical simulator with an innovative auxiliary thermal system. The stress-strain results, macro- and microstructures of SiO2-based ceramic cores were investigated experimentally. The microstructures were characterized by the scanning electron microscope (SEM). The fracture type of the SiO2-based core samples is brittle fracture, but when the temperature exceeds 1400℃, the mechanical behavior exhibits thermo-viscoelastic and viscoplastic property. Under high-temperature (＞1400℃) and stress conditions, the strength of the ceramic core is weakened attributed to the viscous slip of SiO2, which is initially melted at a temperature of 1400℃.

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In Japan, there is a technical barrier of micro hydropower (MHP) small hydropower (SHP) development, which is a lack of skilled about small and micro size technology in the Japanese market. Japanese industries have advanced technology for large-scale hydropower, such as dam facilities, big turbines and generators, electrical control systems. However, in case of small and microscale, there is insufficient capacity in making an accurate assessment of suitability at a local level. In this paper, we challenged to develop the compact hydropower plant package through the practical case study. In Japan, an unused rice-producing districts are increasing, because of the aging and depopulation community. This paper deals with a micro hydro power plant by using the irrigation water for generating power. The power generation project had been done at Oohito community, Miyazaki prefecture in Japan, collaborated with the local SHP development team: local company, university, agricultural association and Asian SHP networks (especially Indonesia and India).

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This paper deals with small and micro hydropower in Japan. After the Great East Japan Earthquake of March 2011 and the nuclear accident in Fukushima, renewable energy attracted great attention as a possible solutions to climate change, greenhouse gas (GHG) emissions and revitalize the local communities with natural capital management at the local level. Historically, hydropower (especially small scale) improved with community-based technology as an appropriate technology. In this paper, we tried to analyze some barriers to small hydropower development in Japan. In the current situation, some countries face similar problems (the problems of aging and depopulation community, economic dependence, liberalization of electricity, energy mixed system etc.) to Japan. The experience we have described from Japan may be of relevance to these countries.

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This study discusses a customized pico hydro system which was developed to harness the water power from Damulog River to be converted as electrical energy source of nearby off-grid community. In order to maximize the flow rate, a penstock was developed, which was patterned to the contour of a typical river with wider open/close tail. Making this generator system versatile to most types of run of river and water surges cause by heavy rains. The system has also modified sprocket, turbine and support pulley which proliferate the speed of the driving system and the output power. Pico-hydroelectric system is an effective way to help the remote areas by generating free and clean electricity. The main objective of the study is to design and install a 75W pico-hydroelectric system in Damulog River which is reliable and low-cost and can be used as a model system to address the still un-electrified rural households in the Philippines.

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J-POWER is promoting development of small hydro power plant projects using potential hydro power resources. One of these projects is “Konokitani hydro power plant” which uses potential head between the outlet of Konokitani mountain stream intake and existing Kuzuryu dam, maximum discharge is 3.22m3/s, normal effective head is 7.4m, and maximum output is 199kW. Since the hydro turbine installation site is submerged in the reservoir at higher water levels, a submersible turbine is adopted. This paper will introduce development and construction of Konokitani HPP in Japan.

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An installation concept of portable type Darrieus hydro turbine in inclined open waterway which is small agricultural waterway is developed. Darrieus turbine have high efficiency at upstream side of the turbine. In the case of installing of the turbine on inclined waterway, removal of downstream weir induces less torque reduction against for much reduction of loss by the drag force.

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Low head hydropower is one of realistic renewable energy. A portable type Darrieus hydro turbine system with a core-less type generator and open type runner is developed. The performance evaluation on portable type Darrieus hydro turbine is carried out.

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In the modern society, environmental problems become serious for influence of global warming. We have developed micro generation system for effective use of unutilized energy and the spread of a self-controlled dispersion energy supply system. The turbine blade was designed by special shape. The turbine was named tornado type turbine. We could realize a turbine with a very complicated shape with a 3D printer. Using 3D printers, it was possible to quickly generate various shape models, and we could compare the hydraulic performances of the seven different turbines. The theoretical output was also calculated using the inflow velocity obtained from the experimental data of each shape model. We found a blade shape for efficiently converting fluid energy into rotational energy.

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Water thermal energy of low temperature becomes in practical usages, by using zeolite crystals as absorbent and heat pump for desorbing out from so called Maracanian state of crystal structure. Temperature elevation in water vapor is accomplished automatically by nature between zeolite crystal and water vapor itself. Desorption of supper heated vapor out from zeolite in the solid-state boiler (SSB) is carried out by use of heat pumps. Vaporization of water is carried out with Infrared Radiation and tornado air jet produced by turbo-air pumps. Those chained mechanisms replace conventional vaporization of water with flame burning of fossil materials and of biomass materials, which also conforms energy flywheel in the system and then produce electric power output based on supplied thermal energy of low temperature water. Detailed explanations are given in the text.

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We investigated the photovoltaic properties of Cu(In,Ga)Se2 (CIGS) solar cells having varying CdS thicknesses ranging from 15 to 60 nm. CIGS solar cells having absorbers fabricated with potassium fluoride post-deposition treatment (KF-PDT) were compared with the as-grown samples. The reduction in CdS thickness decreased the open circuit voltage (VOC) and fill factor (FF) due to the increased minority carrier recombination. The increase in the ideality factor and reverse saturation current was observed in the solar cells having reduced thickness of CdS buffer layer. The reduction in VOC and FF was mitigated by introducing the KF-PDT. Analysis of Nyquist plots revealed that the influence of constant phase element (CPE) was small and independent of the thickness of CdS buffer layer. The capacitance quality of the pn junction of the CIGS solar cells was preserved even with the thin CdS buffer layer having thickness of ~15 nm.

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This study confirmed that usefulness of the vertical axis marine turbine with the variable-pitch control　system by using single actuator disk theory, the numerical calculations and experimental results on the flume and the　towing test in the sea area. The calculation and test model has a diameter of 0.5m, blade length of 0.6m and 6 blades. In　this condition, from the results of the numerical calculation, the flume test and the towing test, it confirmed that high　performance can be obtained the setting angle between -20 degrees and -30degrees.

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