FREAパンフレット（英語）

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Heat exchanger (sheet type)Heat exchanger (slinky type)Heat exchanger(borehole type)17P.8P.10P.12P.14Hydrogen Energy Carrier TeamWind Power TeamPhotovoltaic Power TeamGeothermal Energy TeamShallow Geothermal and Hydrogeology TeamEnergy Network TeamP.6P.8P.10P.12P.14Hydrogen Energy Carrier TeamWind Power TeamPhotovoltaic Power TeamGeothermal Energy TeamEnergy Network TeamP.6● Technology development for GSHP systems optimizationThe team is evaluating the optimal heat exchange system that can eciently utilize a shallow (depth: 1‒2 m) or deep (depth: about 100 m or less) heat exchanger and is developing a more ecient heat exchange system based on site-specic hydrogeological conditions. At the GSHP experiment eld of FREA and at the Geological Museum of AIST in Tsukuba City, identical GSHP systems combining various types of hori-zontal and vertical heat exchangers are installed to investigate and evalu-ate the dierences between the two areas, having dierent hydrogeo-logical settings, in the optimal heat exchange method and their eciency, by long-term monitoring and numerical simulation. Through the “visual-ization” of the GSHP systems, with a real-time display of the operating state and observation of the heat exchange borehole, the team aims to promote and diuse the GSHP system.Activities and AchievementsMain Research FacilitiesThis GSHP system uses a sheet-type heat exchanger and a Slinky-type heat exchanger installed at a depth of 1‒2 m and a vertical-type (borehole type) heat exchanger installed at a depth of about 40 m.FREA Ground-Source Heat Pump System Demonstration AreaFacility at Chulalongkorn University in Thailand used to demonstrate the possibility of cooling operation through the GSHP system in Bangkok.*GSHP: Ground-Source Heat PumpGround-source heat pump (GSHP) system installed at Chulalongkorn University, Thailand1) Analysis of the hydrogeological struc-ture of the Aizu BasinThrough joint research with Fukushima University, the team conducted an analysis of the geological structures of the Quaternary layers and of the hydraulic structure (including subsurface temperature distribution) in the Aizu district, Fukushima Prefecture to recon-struct the basic data for assessing the suitabil-ity of GSHP systems.2) Suitability assessment for GSHP system installation in Aizu BasinThe team constructed a three dimensional groundwater ow and heat transport model based on the geology data obtained from the analysis of geological structure of the Aizu Basin (Fig. 1). Using the model results, the team then conducted a suitability assessment for the closed-loop system, and prepared a distribution map of estimated heat exchange rates (Fig. 2). This kind of suitability map that illustrates the regional variation of heat exchange rates, is essential to select the suitable location for the optimum design of GSHP system.3) Performance evaluation of a closed-loop GSHP air-conditioning system using an artesian wellThe team constructed a closed-loop GSHP system using an artesian well in a joint research project with Japan Groundwater Development Co., Ltd. through the “Program for Promoting Technologies Invented by Industry in Disaster Areas in Tohoku.” The team built a system to control the natural ow using the well temperature. COP higher than 8.0 in the cooling operation and COP higher than 4.5 in the heating operation were observed; however, this depends on the operating conditions.Fig. 1: Three-dimensional groundwater-ow and heat-transport model in the Aizu BasinFig. 2: Distribution map of estimatedheat exchange rate in the Aizu BasinDrilling siteGSHPFan-coil unitA numerical model of a heat exchangerA sheet-type heat exchanger (buried at a depth of 1-2 m)GSGSHH-coil--ccoil