著者
鈴木 杏奈 長谷川 諒 稗貫 峻一 窪田 ひろみ 伊藤 高敏
出版者
日本地熱学会
雑誌
日本地熱学会誌 (ISSN:03886735)
巻号頁・発行日
vol.44, no.3, pp.111-122, 2022-07-25 (Released:2023-01-25)
参考文献数
35

Geothermal potential area in Japan has been depopulated recently, and there have been distances between the geothermal potentials and most energy consumers living in urban areas. Since 2020, working from home (home-based telework) has spread rapidly due to the influence of the COVID-19. If some of the energy consumers work from the geothermal potential area, namely onsen areas, it would help to reduce the extra fossil fuel consumption, to reduce the environmental impact, and to save commuting costs and time. In this study, we quantitatively evaluated the advantages and feasibility of working from onsen in Naruko area, Osaki City, Miyagi Prefecture, as a case study. The environmental effects were analyzed by using the annual CO2 emissions and the costs, based on the perspective of the form of stay and the life-cycle assessments with four scenario conditions ((a) base system, (b) home-based telework in a city, (c) onsen-based telework (using hot spring only for bathing), and (d) onsen-based telework (using hot spring for bathing and heating)). Compared to the base system, the use of public baths in the onsen area can reduce CO2 emissions by about 1/3, and the use of bathing and heating by hot springs can reduce CO2 emissions by about 1/4. In the case of a short-term stay in the onsen area, the effects of reducing CO2 emission differed depending on the area where the worker is based and the season. The results indicates that some conditions of the short-term stay may results in higher CO2 emission than when nothing is done. Therefore, we expect that each of urban workers, companies, and onsen areas will change their awareness and take actions to be able to stay in the onsen area for a mid- to long-term.
著者
益川 敏雄 表 俊一郎 久保寺 章 三浪 俊夫
出版者
日本地熱学会
雑誌
日本地熱学会誌 (ISSN:03886735)
巻号頁・発行日
vol.1, no.1, pp.3-14, 1979-06-30 (Released:2009-08-07)
参考文献数
5
被引用文献数
1

Recently, the Hatchobaru geothermal electric power station of Kyushu Electric Power Co. started its commertial operation on June 1977, under the prescribed power of 50, 000KW. In prior to the completion of the full scale Hatchobaru Power Station, a geothermal power station had been operated since August 1963 at Ohtake, about 2 km distant from the new station to the north. Together with the increase in the development of power production it was planned to improve the micro-earthquake observation network. A new network is composed by one base station and 6 branch stations distributed within an area of 20×20km, in which the Hatchobaru station is acting as the base station locating nearly in the center of the other stations. Each branch station is equipped with one vertical seismometer and is connected to the base station by telephone lines. In the base station all neccesarry devices for micro-earthquake observations are prepared including memory unit, trigger unit, amplifying unit, for-each respective station and a cloock system as well as a recording system. The recording system in Hatchobaru base station is so arranged that the six seismograms of all the seismic stations could be reproduced on one sheet of paper side by side. In doing so reading of seismograms and locating of epicenters could be realized most easily with high acculacy. In this report there are described the newly developed telemeter system for observing the micro-earthquakes in the Hatchobaru geothermal area, together with the some results obtained in the course of the first 8 months test run. These results fairly a satisfactory operation.
著者
三浪 俊夫 久保寺 章 表 俊一郎 木下 保美
出版者
日本地熱学会
雑誌
日本地熱学会誌 (ISSN:03886735)
巻号頁・発行日
vol.3, no.1, pp.43-53, 1981-04-20 (Released:2010-02-05)
参考文献数
20
被引用文献数
1

The area around the Kujyu volcanic mountains that is locating just in the central part of Kyushu Island is named as the Hohi geothermal area. In this region, the Ohtake and the Hatchobaru geothermal electric power stations are currently in operation. In this region, the micro-earthquake observation system has been set up providing six satelite stations connected to the Hatchobaru central station by public cable lines and giving seismograph records displayed on one sheet of paper in the central station. The operation of this micro-earthquake system has started July 1977 with highly increased time accuracy.Analysis of the seismic records for the last two years has yield following results.i) In these two years, about 200 foci of the earthquakes that occurred in this region have been located. All of these earthquakes gave the magnitudes smaller than M=3. These earthquakes could be classified into two groups. One was a group of earthquakes that might be related to the characteristic tectonics in the geothermal area, and the other were the earthquake that may be related either to the earthquake swarm activity in the northern part of the Aso caldera or the aftershock activity of the Oita earthquake of 1975.ii) The micro-earthquakes that are proper to the geothermal area were seen arranged in a belt zone along fault lines that are developed clearly in this region. In this belt zone swarm type microearthquake activities were observed showing the short duration period of swarm occurrence and shifting the swarm activity from one place to another.iii) For the purpose of obtaining more accurate focal locations, re-determination of the foci of all these swarm earthquakes were carried out by the aid of the improved master event method.As the result of which, it was made clear that foci distribution of each of these earthquake swarm was bounded in a narrow volume having the horizontal and vertial dimensions of 500 m x 2 km, extending almost vertically.iv) With regard to these earthquakes in the swarm, the study was carried out for making clear the earthquake occurrence mechanism of these earthquakes. It was found that earthquakes that occurred in the area near the Aso caldera, showed a mechanism represented by the right-lateral fault movement and for the earthquakes that took place along the geological fault zone, they showed a normal fault type mechanism.v) Within the low gravity area represented by the Kujyu caldera, locating in the north-eastern part of the Kujyu mountain range, almost any micro-earthquake activity is not observed.
著者
安川 香澄 野田 徹郎
出版者
日本地熱学会
雑誌
日本地熱学会誌 (ISSN:03886735)
巻号頁・発行日
vol.39, no.4, pp.203-215, 2017-10-25 (Released:2018-04-25)
参考文献数
16
被引用文献数
2

A criterion to evaluate possible influence of geothermal development onto nearby hot spring aquifer, based on geochemical characteristic of the aquifer, was developed in a form of decision tree. Hydraulic and thermal connection of a geothermal reservoir to nearby hot spring aquifer may be expressed by five types of simplified structure models, which are, identical thermal water-, seepage thermal water-, steam heated-, heat conduction- and independent- systems. Since interference of geothermal fluid production differs depend on such types, required monitoring items for protection of hot spring aquifers also differ for each type. The type of relationship between a specific geothermal reservoir and a nearby hot spring aquifer can be roughly estimated by temperature and anion characteristics of the hot spring waters for volcanic geothermal systems. In a former study, a criterion was developed based on five types of geochemical characteristics of hot spring waters. However, such a categorization was not quite successful when volcanic gas or CO2 gas was supplied to the aquifer or geometrical setting was not appropriate. Although hydraulic relationship is well described by five types, geochemical characteristics of hot springs are not well represented by five types only. Therefore in this study, a new criterion was developed by adding two new types, CO2 gas supply and volcanic gas supply types, resulting in seven types in total. Spatial arrangement of the target aquifer and geothermal reservoir is also taken into consideration. The threshold values in this criterion are based on data sets obtained from hot spring wells and natural geothermal manifestations all over Japan. Then the new criterion was applied to hot spring waters in Kuju region, Oita, Japan where three geothermal power plants are in operation. As a result, all seven types were identified for this region. It was found that hot springs of seepage thermal water type and steam heated type densely exist near geothermal power plants, suggesting that such hot spring type identification may be an effective tool for geothermal exploration. The new criterion, which helps to estimate effects of geothermal development onto each nearby hot spring aquifer and enables to protect hot springs against excess geothermal development, may be applied for other volcanic geothermal regions.
著者
松田 雅司 鈴木 陽大 井岡 聖一郎 村岡 洋文
出版者
日本地熱学会
雑誌
日本地熱学会誌 (ISSN:03886735)
巻号頁・発行日
vol.39, no.2, pp.73-79, 2017-04-25 (Released:2017-10-26)
参考文献数
19

The southwestern foot of the Hakkoda–Odake volcano has many geothermal manifestations where geothermal development has been limited by the Natural Parks Law. The current target area, which is classified as Class II special zone has been deregulated for individual geothermal development. We conducted an investigation to determine the chemical and isotopic characteristics of the hot waters around the Shinyu Fault and to estimate the temperature of the geothermal reservoir. According to our δD–δ18O diagram, the hot waters in the study area are meteoric in origin. In addition, the triangle diagram for Cl–, SO42–, and HCO3– concentrations indicates that these hot waters can be classified as steam-heated waters and volcanic waters. The B/Cl and Br/Cl ratios show that the volcanic waters are diluted with shallow groundwater as they flow through Jigokunuma downstream to Shinyu. We estimated the geothermal reservoir temperature to be between approximately 150 and 160 °C, based on anhydrite geothermometry and the chloride–enthalpy mixing diagram.
著者
金子 正彦
出版者
日本地熱学会
雑誌
日本地熱学会誌 (ISSN:03886735)
巻号頁・発行日
vol.38, no.3, pp.85-100, 2016-07-25 (Released:2017-01-25)
参考文献数
28

Geothermal energy laws in other countries may be great reference when Japan considers enhancing its own legal framework to promote geothermal energy development. This paper follows the previous paper of “Geothermal Energy Laws in the World” which was placed in the Journal of Geothermal Research Society of Japan, vol. 34, No.3 (2012). The previous paper surveyed geothermal energy laws of nine major geothermal countries including the U.S., the Philippines, New Zealand, Iceland and Japan. This paper is a supplemental paper to provide information of geothermal energy law of other countries such as Indonesia, Mexico, Italy, Turkey, Costa Rica, Peru and Ethiopia. The surveys show; (i) Each country has its own geothermal energy law to promote geothermal energy development. (ii) Hot Spring Law, that was enacted to regulate small wells for thermal baths, is also used to regulate large-scale wells for geothermal power plants in Japan. There are, however, many inconvenience arise from adapting Hot Spring Law to geothermal energy development. (iii) Japan needs to enact its own “Geothermal Energy Law,” of which objective is to control and to promote geothermal energy development, with reference of other countryʼs geothermal laws.
著者
ルーター ホルスト 日本地熱学会国際交流委員会
出版者
日本地熱学会
雑誌
日本地熱学会誌 (ISSN:03886735)
巻号頁・発行日
vol.35, no.1, pp.45-47, 2013-01-25
参考文献数
1

地熱資源を使うことは,ドイツの長期的な再生可能エネルギー利用の一部であり,それには地熱発電と,主として浅部での地中熱ヒートポンプを利用した暖房(および冷房)が含まれる。すべての原子力発電所を廃止するという政府の決定以降,あらゆる再生可能エネルギーの利用が加速している。決定からの期間がまだ短いため実際のマスタープランは無いが,原子力発電の置き換えに関するシナリオが数多くある。エネルギー生産のほかに,輸送(新しい送電線)および貯蔵が主要な問題である。<br>ほとんどのシナリオでは,地熱は小さな役割しか果たしておらず,全く抜けている場合さえある。しかし,電力供給網を安定させるベースロードとなるものが必要であること, 輸送と貯蔵の需要を減らす必要があることを理解すべきである。<br>暖房・冷房の市場では,地熱の導入(ほとんどが浅い地中熱)が普及しており,成長率が高い。近い将来,地熱供給は,太陽熱・マイクロ熱-電力に並び,主要なエネルギー源となるであろう。
著者
ジャリリナスラバディ サイード 糸井 龍一 ヴァルディマルソン ポール 藤井 光 田中 俊昭
出版者
日本地熱学会
雑誌
日本地熱学会誌 (ISSN:03886735)
巻号頁・発行日
vol.33, no.3, pp.113-121, 2011-07-25
参考文献数
19

サバラン地熱地域はイラン国の東北部に位置し,現在開発が進められている。建設予定のシングルフラッシュ型発電所の分離熱水が有するエネルギーとエクセルギーは生産流体の全エネルギーおよび全エクセルギーのそれぞれ54.8%,41.4%を占める。分離熱水は複合発電および地域熱利用システムに利用することができる。この分離熱水活用のためにシングルフラッシュ型発電所と併せた複合発電システムとしてバイナリー発電を採用した場合のフィージビリティスタディをおこなった。その結果バイナリー発電所の出力として17,151kWが得られた。エネルギーおよびエクセルギーに関する数学モデルを構築し,それをソフトウェアEngineering Equation Solverを用いて解析を行った。その結果,凝縮器と蒸発器において最大のエクセルギー損失が発生し,エクセルギー全損失に占める割合はそれぞれ12.1%,33.4%である。バイナリー発電所のエネルギー効率およびエクセルギー効率は,それぞれ6.25%および34.4%である。さらに,グラスマン図を用いてバイナリー発電所内におけるエクセルギーの全体的な流れを示した。これらの結果より,エクセルギー解析を行うことは生産されたエネルギーを地熱発電所にて最適に利用するうえで有用であることを明らかにした。
著者
RIOGILANG Hendra 糸井 龍一 田口 幸洋
出版者
日本地熱学会
雑誌
日本地熱学会誌 (ISSN:03886735)
巻号頁・発行日
vol.34, no.3, pp.151-159, 2012

コタモバグ地熱地域の東西30 km,南北20 km において温泉水および関連した水の地化学調査を実施した。温泉水,河川水からなる31 試料を標高173 m から1438 m の間で採取し,化学成分および水の安定同位体比を測定した。同時に雨水を標高556 m から1500 m の間の5 地点で,2010 年3 月から6月にかけて採取した。ほとんどの温泉水は中性のHCO<sub>3</sub> 型および複合型であり,水の安定同位対比のグローバルな天水線上に分布し,天水起源であることを示唆している。しかし,酸性の水はこの天水線からずれている。Muayat 山の山頂付近の噴気地帯近傍で採取された試料(MUAH-16)はSO<sub>4</sub> タイプであり,蒸気加熱型であることを示唆している。酸性水試料が安定同位体の天水線からずれている原因は地表あるいは浅層での天水の蒸発と考えられる。中性でかつ本地域の天水線の&delta;<sup>18O</sup>からずれている試料LOBH-10 は本地域の周辺部に位置し,このずれは海生起源の岩石との反応が原因と考えられる。
著者
大久保 泰邦 秋田 藤夫 田中 明子
出版者
日本地熱学会
雑誌
日本地熱学会誌 (ISSN:03886735)
巻号頁・発行日
vol.20, no.1, pp.15-29, 1998-01-25
参考文献数
25
被引用文献数
8
著者
最首 花恵 小坂 拓也 土屋 範芳 渡邉 則昭
出版者
日本地熱学会
雑誌
日本地熱学会誌 (ISSN:03886735)
巻号頁・発行日
vol.39, no.1, pp.15-24, 2017-01-25 (Released:2017-07-25)
参考文献数
19

Hydrogen produced by the water-splitting reaction is one of the alternate sources derived from fossil fuels. However, the present systems for the hydrogen production still require the extra energy or processes such as heating, milling and adding the chemical agent. The hot springs in Japan are naturally in high temperature and in wide range of pH. We investigated the combination of hot spring water and waste aluminum that are appropriate for hydrogen production without extra energy. Here, we used waste aluminum for reducer of water-splitting reactor. The hydrogen production system in Onsen (hot spring) area has a potential to promote not only the environmental and energy problems but also the activation of the local community as the system of “local production for local consumption”. In this study, the effects of the characters of hot springs and the conditions of the hydrogen generator system were revealed by the laboratory experiments. The water-splitting reaction was enhanced by using the hot spring water of (1) lower pH (< 2), (2) higher temperature, and (3) higher ratio of HCl/H2SO4. The concentration of cations in the fluid is not related to the reaction rate of hydrogen production. The prototype of the hydrogen generator for the water splitting reaction by using the acidic hot spring water and waste aluminum was developed and used in two type systems: batch and flow-through. The laboratory experiment by using the original generator revealed that hydrogen production was more efficient in the flow-through system because of constant pH value of fluid.
著者
太田 一也
出版者
日本地熱学会
雑誌
日本地熱学会誌 (ISSN:03886735)
巻号頁・発行日
vol.28, no.4, pp.337-346, 2006-10-25 (Released:2009-08-07)
参考文献数
28

Many hot springs are gushing from the inside of the Unzen Graben which traverses the central part of Unzen Volcano in east-west direction. Their geochemical characteristics are of salt type at the western foot, of sulfur type at the central mountain area and of bicarbonate type at the eastern foot of the volcano. They are hot in the west and warm in the east. A hydrothermal system at Unzen Volcano was presented by Ohta (1972) that the original magmatic emanations are supplying from a magma reservoir which lies beneath the Tachibana Bay assuming Chijiwa Caldera located at western side of volcano, and also that magmatic emanations have been ascending obliquely toward the east generating each type of thermal waters corresponding to the degree of differentiation. But this hydrothermal system was not accepted widely. Unzen Volcano began to erupt in November 1990 after 198 years dormancy. The forgoing earthquake swarm occurred beneath the Tachibana Bay in November 1989, and the foci migrated toward the summit of the volcano repeatedly for One year. They are arranged in semicircle at the southern part of Tachibana Bay and in a parallel two lines which run from the bay to the summit as if indicating the caldera rim and the conduit, respectively. Deformation of ground during the eruptions also showed that pressure sources were underlain beneath the inside of the parallel foci lines, and final pressure source was detected beneath the Tachibana Bay (Matsushima et al., 2003, 2005). So, the hydorothermal system presented by Ohta (1972) may be proved to be true because of these new facts. Based on these, modified supplying model of magmatic emanations were proposed here.