Milestone-Proposal:Matsukawa Geothermal Power Plant, 1966
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Docket #:2025-22
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To the proposer’s knowledge, is this achievement subject to litigation? No
Is the achievement you are proposing more than 25 years old? Yes
Is the achievement you are proposing within IEEE’s designated fields as defined by IEEE Bylaw I-104.11, namely: Engineering, Computer Sciences and Information Technology, Physical Sciences, Biological and Medical Sciences, Mathematics, Technical Communications, Education, Management, and Law and Policy. Yes
Did the achievement provide a meaningful benefit for humanity? Yes
Was it of at least regional importance? Yes
Has an IEEE Organizational Unit agreed to pay for the milestone plaque(s)? Yes
Has the IEEE Section(s) in which the plaque(s) will be located agreed to arrange the dedication ceremony? Yes
Has the IEEE Section in which the milestone is located agreed to take responsibility for the plaque after it is dedicated? Yes
Has the owner of the site agreed to have it designated as an IEEE Milestone? Yes
Year or range of years in which the achievement occurred:
1966
Title of the proposed milestone:
Matsukawa Geothermal Power Plant, 1966
Plaque citation summarizing the achievement and its significance; if personal name(s) are included, such name(s) must follow the achievement itself in the citation wording: Text absolutely limited by plaque dimensions to 70 words; 60 is preferable for aesthetic reasons.
Matsukawa Geothermal Power Plant, constructed in 1966 by Nippon Heavy Chemical Industry with support from domestic manufacturers, has been continuously operated by the Tohoku Electric Power Group. As Japan’s first commercial geothermal facility, its technical achievements and operational experience have significantly influenced geothermal development across the country and informed the design and construction of geothermal plants internationally
200-250 word abstract describing the significance of the technical achievement being proposed, the person(s) involved, historical context, humanitarian and social impact, as well as any possible controversies the advocate might need to review.
The Matsukawa Geothermal Power Plant, commissioned in 1966, is Japan’s first commercial geothermal facility and the earliest of its kind in Asia. Built in the Hachimantai Plateau of Iwate Prefecture, the plant overcame significant technical, political, and geographical challenges to become a model of renewable energy development. Engineers successfully adapted dry steam technology—first pioneered in Italy and the United States—to Japan’s unique geological conditions, innovating turbine designs and corrosion-resistant materials to manage low-pressure, gas-rich steam reservoirs.
The plant’s location within Towada-Hachimantai National Park required environmental safeguards and community engagement, establishing a model for sustainable development within environmentally protected regions. Unlike earlier geothermal plants abroad, Matsukawa integrated its operations with regional agriculture and tourism, repurposing geothermal byproducts for hot spring facilities and greenhouse heating.
Matsukawa’s success demonstrated the feasibility of geothermal energy in Japan’s volatile terrain and influenced national energy policy, especially after the 2011 Fukushima disaster. Recognized as a Mechanical Engineering Heritage site in 2016, it continues to serve as an educational hub and a symbol of innovation, safety, and resilience. Its enduring performance over five decades underscores its legacy and impact, inspiring subsequent geothermal initiatives across Japan and Asia.
Its sustained operation for over five decades and its contributions to science, policy, and international collaboration make it a fitting recipient of the IEEE Milestone recognition.
IEEE technical societies and technical councils within whose fields of interest the Milestone proposal resides.
In what IEEE section(s) does it reside?
IEEE Sendai section
IEEE Organizational Unit(s) which have agreed to sponsor the Milestone:
IEEE Organizational Unit(s) paying for milestone plaque(s):
Unit: IEEE Sendai Section
Senior Officer Name: Hiroaki Muraoka
IEEE Organizational Unit(s) arranging the dedication ceremony:
Unit: IEEE Sendai Section
Senior Officer Name: Hiroaki Muraoka
IEEE section(s) monitoring the plaque(s):
IEEE Section: IEEE Sendai Section
IEEE Section Chair name: Hiroaki Muraoka
Milestone proposer(s):
Proposer name: Chiaki Ishikawa
Proposer email: Proposer's email masked to public
Proposer name: Hayato Abe
Proposer email: Proposer's email masked to public
Please note: your email address and contact information will be masked on the website for privacy reasons. Only IEEE History Center Staff will be able to view the email address.
Street address(es) and GPS coordinates in decimal form of the intended milestone plaque site(s):
MATSUKAWA GEOTHERMAL MUSEUM, Matsuo-Yosegi, Hachimantai-shi, Iwate, 028-7302, Japan
GPS Coordinate: 39.8722254,140.9198014,16.77
Photo of MATSUKAWA GEOTHERMAL MUSEUM
Describe briefly the intended site(s) of the milestone plaque(s). The intended site(s) must have a direct connection with the achievement (e.g. where developed, invented, tested, demonstrated, installed, or operated, etc.). A museum where a device or example of the technology is displayed, or the university where the inventor studied, are not, in themselves, sufficient connection for a milestone plaque.
Please give the details of the mounting, i.e. on the outside of the building, in the ground floor entrance hall, on a plinth on the grounds, etc. If visitors to the plaque site will need to go through security, or make an appointment, please give the contact information visitors will need.
Are the original buildings extant?
Yes.
Details of the plaque mounting:
How is the site protected/secured, and in what ways is it accessible to the public?
Who is the present owner of the site(s)?
What is the historical significance of the work (its technological, scientific, or social importance)? If personal names are included in citation, include detailed support at the end of this section preceded by "Justification for Inclusion of Name(s)". (see section 6 of Milestone Guidelines)
Historical Significance of the Matsukawa Geothermal Power Plant
Introduction
Commissioned in 1966 in Iwate Prefecture, Japan, the Matsukawa Geothermal Power Plant is historically significant as the first commercial geothermal facility in Japan and Asia. It represents a pivotal moment in the global adoption of renewable energy and remains a model of technological innovation, sustainability, and environmental integration.
Photo 1 Left: Power generation building; Right: Cooling tower
Photo 2 Assembling the steam turbine
Photo 3 Assembling the generator
Technological Innovation and Pioneering Application
Adoption of Dry Steam Method
The significance of the Matsukawa plant begins with its adoption of the dry steam geothermal power generation method, a process in which high-temperature steam from deep underground reservoirs is directly fed into turbines to generate electricity. This method, though simple in principle, requires exceptionally suitable geological conditions and advanced engineering controls.
Integration with Global Pioneers
Matsukawa’s adoption of the dry steam technique followed pioneering implementations in Italy’s Larderello and the Geysers in California, positioning Japan as an early contributor to global geothermal development.
Engineering Achievements in Japan
The plant was developed in collaboration with Japanese academia and industrial sectors, developing uniquely Japanese innovations in turbine design—such as pressure-adaptive nozzles and anti-corrosion materials—based on field data collected under challenging geological conditions. These innovations directly influenced Japan’s industrial standards in geothermal plant design and monitoring systems.
Scientific Contributions to Geothermal Resource Utilization
Long-Term Geological Insights
The Matsukawa Geothermal Power Plant offered researchers a rare opportunity to gather long-term data on subsurface geothermal systems in a region previously unexplored for power generation. However, the acquisition of reliable geological data in the 1960s posed significant challenges. At the time, Japan lacked advanced downhole sensors and digital monitoring equipment. Temperature and pressure readings were taken manually using mechanical gauges, which required trained personnel to operate under hazardous high-temperature conditions at wellheads.
Moreover, the steam at Matsukawa contained hydrogen sulfide concentrations exceeding 300 ppm and chloride ions over 1,000 mg/L, levels that caused significant corrosion to early turbine materials and piping. Instruments had to be frequently recalibrated or replaced, slowing down research progress and increasing operational costs. Despite these obstacles, engineers and geologists compiled valuable datasets over time, enabling the development of early models for reservoir behavior, steam mineral content, and pressure decline. These empirical insights laid the groundwork for improved reservoir management strategies and future exploration across Japan.
Collaborative Research and Education
Through partnerships with universities and research institutes, the plant served as a “living laboratory,” fostering scientific inquiry and field-based learning.
National Resource Exploration Impact
The success of Matsukawa validated high-enthalpy geothermal zones in Japan, driving nationwide efforts in geothermal exploration and improving technologies for subsurface imaging and seismic resilience.
Social and Environmental Importance
Energy Security for Japan
Commissioned during Japan’s post-war industrial expansion, Matsukawa contributed to energy diversification and reduced dependence on imported fossil fuels—an impact amplified in the post-Fukushima energy landscape.
Regional Economic Development
The plant supported the rural Hachimantai region by creating jobs, improving infrastructure, and supplying heat to spas, greenhouses, and aquaculture, demonstrating sustainable community integration.
Ecological Stewardship
The development of Matsukawa within Towada-Hachimantai National Park required extraordinary attention to environmental impact, particularly given the site's protected status. Early in the planning phase, environmental regulators imposed strict conditions on drilling and construction activities. For example, only limited surface disturbance was allowed, prompting engineers to design compact well pads and to avoid the felling of old-growth trees. Heavy machinery and materials had to be transported via narrow, newly constructed roads that avoided ecologically sensitive areas.
Furthermore, discharge of used geothermal fluids posed a risk to local streams and groundwater. To address this, the project team implemented one of Japan’s earliest on-site fluid treatment systems, using lime neutralization and controlled reinjection techniques to manage acidic effluents. These environmental precautions not only allowed the project to proceed within a national park but also established the first successful case of geothermal power generation within a Japanese national park, setting a precedent for environmentally regulated energy infrastructure nationwide.
Recognition and Enduring Legacy
National Engineering Heritage
In 2016, Matsukawa was named a Mechanical Engineering Heritage site by The Japan Society of Mechanical Engineers (JSME), acknowledging its pioneering role and exceptional operational durability.
Educational and Policy Influence
Its history is featured in academic curricula and professional training programs. It continues to shape national energy policy and inspire future generations of energy engineers and scientists.
Its operational practices and environmental design have been referenced by international geothermal associations, including the International Geothermal Association (IGA), affirming its global relevance."
Catalyst for Domestic and International Geothermal Expansion
The successful operation of the Matsukawa Geothermal Power Plant served as a springboard for Japan's national geothermal energy program. Building upon the technical and operational insights gained at Matsukawa, Japan has since developed over 20 commercial geothermal power stations with a combined installed capacity exceeding 530 megawatts as of 2024. These include prominent plants such as Onuma, Otake, Hatchobaru, and Mori, each incorporating lessons in reservoir management, corrosion control, and turbine optimization pioneered at Matsukawa.
Furthermore, Japan's geothermal engineering expertise, fostered through Matsukawa's legacy, has played a vital role in international cooperation. Japanese firms and researchers have contributed to geothermal development projects in countries such as Indonesia, the Philippines, Kenya, and Mexico—offering support in resource assessment, plant design, and environmental management. This international engagement reflects Matsukawa's broader impact not only on domestic energy diversification but also on the global advancement of sustainable geothermal technology.
Conclusion
The Matsukawa Geothermal Power Plant is historically significant for being one of the earliest commercial geothermal facilities globally and the first in Japan. It exemplifies enduring technological innovation, scientific advancement, and socio-environmental value. Its lasting legacy affirms its candidacy for recognition under the IEEE Milestone program.
What obstacles (technical, political, geographic) needed to be overcome?
Overcoming Obstacles in the Development of the Matsukawa Geothermal Power Plant
The establishment of the Matsukawa Geothermal Power Plant in 1966 marked a pioneering achievement in Japan’s energy history. The project faced considerable technical, political, and geographic challenges that had to be resolved for its successful implementation. The project faced and overcame a complex interplay of technical, political, and geographic obstacles, each of which shaped the plant’s design, implementation, and long-term success.
Technical Challenges
Lack of Precedent and Domestic Expertise
At the time of Matsukawa’s conception, Japan had no prior experience in commercial geothermal power generation. The dry steam method, used successfully in Italy’s Larderello and California’s Geysers, had never been implemented in Japan. Engineers and scientists had to adapt foreign technologies to Japan’s unique geological conditions, often without direct access to proprietary designs or operational data.
Steam Quality and Equipment Durability
The geothermal steam at Matsukawa contained corrosive gases such as hydrogen sulfide, which posed risks to turbine blades and piping systems. Developing materials and coatings that could withstand long-term exposure to these elements required extensive research and testing. The team had to innovate in metallurgy and fluid handling to ensure operational stability and safety.
Reservoir Management and Sustainable Output
Understanding the geothermal reservoir’s behavior was another major hurdle. Without modern modeling tools, engineers relied on empirical data and trial-and-error drilling to locate viable steam sources. Maintaining sustainable output over decades required careful sizing of the plant and conservative extraction strategies, which were not common practice at the time.
Political and Regulatory Barriers
Energy Policy and Institutional Support
In the 1950s and 60s, Japan’s energy policy was heavily focused on coal and hydroelectric power, with emerging interest in nuclear energy. Geothermal was not yet recognized as a strategic resource. Convincing policymakers and utility companies to invest in an unproven technology required persistent advocacy and demonstration of long-term benefits.
Land Use and National Park Restrictions
The Matsukawa site is located within the Towada-Hachimantai National Park, a protected area with strict land-use regulations. Securing permits for drilling and construction involved negotiations with environmental agencies and local governments. The project had to demonstrate minimal ecological impact and incorporate environmental safeguards into its design.
Public Perception and Local Engagement
Geothermal energy was largely unknown to the public, and early drilling efforts were met with skepticism. Initial surveys were conducted under the guise of expanding hot spring resorts, and only later repurposed for power generation. Building trust with local communities and stakeholders was essential, especially in a region dependent on tourism and agriculture.
Geographic and Geological Constraints
Remote and Mountainous Terrain
The plant’s location in the Hachimantai Plateau presented logistical difficulties. Transporting heavy equipment and materials to the site required the construction of access roads and infrastructure in rugged terrain. Seasonal weather conditions, including heavy snowfall, further complicated construction and maintenance efforts.
Volcanic Activity and Seismic Risk
Japan’s tectonic setting posed inherent risks to geothermal development. The region’s volcanic activity and frequent earthquakes necessitated robust structural design and contingency planning. Engineers had to ensure that wells, pipelines, and turbines could withstand seismic events without compromising safety or performance.
Unpredictable Subsurface Conditions
Drilling into geothermal reservoirs is inherently uncertain. Early exploratory wells at Matsukawa yielded inconsistent results, with some producing only hot water or non-viable steam. The team had to refine drilling techniques and develop better geological survey methods to improve success rates and reduce financial risk.
Legacy of Overcoming Challenges
The successful commissioning of the Matsukawa Geothermal Power Plant was a testament to Japan’s engineering ingenuity and collaborative spirit. By overcoming these multifaceted obstacles, the project laid the foundation for future geothermal development in Japan and Asia. It demonstrated that with careful planning, interdisciplinary cooperation, and adaptive problem-solving, renewable energy could thrive even in challenging environments. Today, Matsukawa stands not only as a functional power station but also as a symbol of resilience and innovation. Its continued operation for over five decades reflects the effectiveness of the solutions devised to address its early challenges—solutions that remain relevant to geothermal projects worldwide.
What features set this work apart from similar achievements?
Unique Features Compared to Global Predecessors
The Matsukawa Geothermal Power Plant, commissioned in 1966, holds a unique place in the global history of geothermal energy. While geothermal power had already been harnessed in countries such as Italy, the United States, and New Zealand, Matsukawa distinguished itself through its technological adaptations, environmental integration, and its role in shaping Japan’s renewable energy landscape. This section outlines the features that set Matsukawa apart from its international counterparts and highlights its pioneering contributions.
First Commercial Geothermal Plant in Japan and Asia
Matsukawa was the first commercial geothermal power plant in Japan and the broader Asian region, marking a significant milestone in the diversification of energy sources in a country heavily reliant on imported fossil fuels. Unlike Italy’s Larderello (1911) and the United States’ The Geysers (1960), which were situated in regions with long-standing geothermal traditions, Matsukawa represented a significant technological advancement in a region with no prior commercial geothermal development. Its success demonstrated the viability of geothermal energy in a new geological and regulatory context, paving the way for future developments across Asia.
Adaptation of Dry Steam Technology to Japan’s Volcanic Geology
While Matsukawa adopted the dry steam method pioneered at Larderello and The Geysers, its implementation in Japan’s volcanic terrain required significant technological adjustments. The steam reservoirs beneath the Hachimantai Plateau featured lower pressure and higher concentrations of acidic gases than those in Tuscany or California. As a result, off-the-shelf turbines imported from overseas were poorly matched to the local steam characteristics, leading to low power output and frequent component degradation during initial trials.
In response, Japanese engineers modified the turbine design to operate efficiently under reduced inlet pressure and variable steam composition. Custom gas scrubbers were introduced upstream of the turbines to remove hydrogen sulfide and particulates, extending equipment life and reducing emissions. Additionally, drainage systems were reconfigured to prevent scaling from silica-rich condensate. These adaptations not only ensured reliable performance but also marked an important step in the localization of geothermal technology for Japan’s unique geological environment.
Integration with Environmental and Agricultural Systems
One of Matsukawa’s most distinctive features is its integration with local environmental and agricultural systems. Located within the Towada-Hachimantai National Park, the plant was designed with minimal ecological disruption. Waste hot water from the plant is repurposed for greenhouse heating and hot spring facilities, demonstrating a holistic approach to resource utilization. This contrasts with earlier plants like The Geysers, which focused primarily on electricity generation without significant secondary applications.
Community Engagement and Public Acceptance
Unlike its Western counterparts, Matsukawa’s development involved extensive community engagement. Initial drilling was conducted under the guise of expanding hot spring resorts, and only later transitioned to power generation. This gradual approach helped build public trust and acceptance in a region where geothermal energy was unfamiliar. In contrast, plants like Wairakei in New Zealand faced early criticism over environmental impacts, including subsidence and changes to geyser activity.
Mechanical Engineering Heritage Recognition
In 2016, Matsukawa was designated a Mechanical Engineering Heritage site by the Japan Society of Mechanical Engineers. This recognition underscores its historical and technical significance, not only as a power generator but as a symbol of Japan’s engineering ingenuity. While Larderello and The Geysers are celebrated for their scale and longevity, Matsukawa is honored for its pioneering spirit and its role in establishing geothermal energy as a viable option in Japan’s energy mix.
Operational Longevity and Stability
Matsukawa has maintained stable operations for over five decades, a testament to its robust design and sustainable resource management. While The Geysers experienced fluctuations in output due to reservoir depletion and required reinjection strategies, Matsukawa’s conservative extraction and reservoir monitoring have ensured consistent performance. This operational stability is particularly notable given Japan’s seismic activity and the plant’s location in a mountainous region.
Educational and Demonstration Role
Matsukawa has served as a model and educational site for geothermal development in Japan. The establishment of the Matsukawa Geothermal Hall and its use in training engineers and policymakers has amplified its impact beyond electricity generation. In contrast, earlier plants were primarily industrial in focus, with limited public outreach or educational initiatives.
Strategic Importance Post-Fukushima
Following the 2011 Fukushima Daiichi nuclear disaster, Matsukawa gained renewed attention as a symbol of safe and renewable energy. Its long-standing operation and minimal environmental footprint positioned it as a credible alternative to nuclear power. This strategic relevance distinguishes it from older plants that were not developed with disaster resilience or public safety in mind.
Conclusion
While geothermal power had been successfully harnessed in Italy, the United States, and New Zealand prior to Matsukawa’s commissioning, the Japanese plant introduced a new paradigm in geothermal development. Its adaptation of dry steam technology to Japan’s unique geology, its integration with local ecosystems, and its emphasis on public engagement and long-term sustainability set it apart from its predecessors. Matsukawa’s legacy continues to inspire geothermal innovation across Asia and serves as a benchmark for responsible and resilient energy development.
Why was the achievement successful and impactful?
Success Factors and Impact of the Matsukawa Geothermal Power Plant
The Matsukawa Geothermal Power Plant, commissioned in 1966, stands as a landmark achievement in Japan’s energy history. Its success and impact stem from a combination of technical innovation, strategic foresight, environmental stewardship, and social engagement. As Japan’s first commercial geothermal power station, Matsukawa not only proved the viability of geothermal energy in a new regional context but also laid the foundation for future renewable energy development across Asia.
Technical Success Through Adaptation and Innovation
Matsukawa’s operational success hinged on its engineers’ ability to adapt dry steam technology—originally developed in Italy and the United States—to Japan’s distinct geological and chemical conditions. One of the earliest technical challenges was the unexpectedly low reservoir pressure, which led to unstable turbine operation during test runs. Imported turbine models failed to deliver sufficient efficiency, prompting the redesign of nozzle geometry and the addition of pressure-regulating bypass valves.
Moreover, the geothermal steam at Matsukawa contained corrosive gases such as hydrogen sulfide, as well as silica deposits, which eroded and fouled turbine blades and piping systems. Initial prototypes experienced pitting and metal fatigue after only a few hundred hours of operation. The engineering team conducted extensive material tests, ultimately settling on high-nickel stainless steel alloys and specialized coatings to withstand the chemical environment. These innovations not only ensured long-term stability but also contributed to the development of Japan’s industrial standards for geothermal plant components.
Strategic Timing and National Relevance
The plant’s commissioning coincided with Japan’s post-war industrial expansion and growing energy demands. At a time when the country was heavily reliant on imported fossil fuels, Matsukawa offered a domestic, renewable alternative. Its success demonstrated that geothermal energy could contribute meaningfully to Japan’s energy mix, influencing policy discussions and encouraging further exploration. In the wake of the 2011 Fukushima nuclear disaster, Matsukawa's proven track record of safe, clean, and decentralized energy production re-emerged as a compelling alternative to nuclear power, influencing Japan’s post-disaster energy strategy.
Environmental Integration and Resource Efficiency
Located within the Towada-Hachimantai National Park, Matsukawa was designed with minimal ecological impact. Its operations exemplify resource efficiency: waste hot water is repurposed for agricultural greenhouses and local hot spring facilities. This multi-use approach not only reduced environmental footprint but also strengthened ties with the local economy. The plant’s ability to coexist with protected natural areas set a precedent for environmentally responsible energy development.
Social Engagement and Educational Value
Matsukawa’s development involved close collaboration with local communities, transforming initial skepticism into support. The establishment of the Matsukawa Geothermal Hall and its use as an educational site helped raise public awareness about geothermal energy. The plant became a model for community-integrated renewable projects, demonstrating that technical success must be accompanied by social acceptance to achieve lasting impact.
Recognition and Legacy
In 2016, Matsukawa was designated a Mechanical Engineering Heritage site by the Japan Society of Mechanical Engineers, affirming its historical and technical significance. Its continued operation and influence on geothermal policy and education underscore its enduring legacy. Matsukawa’s success is not merely measured in megawatts, but in its role as a catalyst for innovation, sustainability, and public trust in renewable energy.
Supporting texts and citations to establish the dates, location, and importance of the achievement: Minimum of five (5), but as many as needed to support the milestone, such as patents, contemporary newspaper articles, journal articles, or chapters in scholarly books. 'Scholarly' is defined as peer-reviewed, with references, and published. You must supply the texts or excerpts themselves, not just the references. At least one of the references must be from a scholarly book or journal article. All supporting materials must be in English, or accompanied by an English translation.
References
[1] Mitsuyuki Hanano, Koichi Kotanaka, Takashi Oyama: “Operation and Reservoir Management of the Matsukawa Geothermal Power Station”, Journal of the Geothermal Research Society of Japan, pp. 1-25, Vol. 26, No. 2 (ser. 107), 1989.
Abstract:
This paper reports operation and reservoir management of the Matsukawa geothermal power plant. This includes a summary of the production records of the power plant and well head data of all the wells, a review of the results of physical and chemical reservoir monitoring, and a discussion on current issues for stable operation of the power plant.
The Matsukawa geothermal power station has a vapor dominated geothermal reservoir which has been the only extensive one found in Japan. The first ever geothermal power generation in Japan was started in Matsukawa in October 1966 by Japan Metals and Chemicals Co., Ltd. Power generation at Matsukawa has been continued successfully for more than twenty-two years. The present output is 22 MW with 10 production wells. Cumulative electric energy produced, an average output and the utilization factor over twenty-two years are 3.53 x 106MWh, 19.6MW and 86 percent respectively,
Water level monitoring and pressure build-up test have been conducted as a physical reservoir monitoring. From the water level monitoring at a well T-22 which is located at the center of the production area, an approximate average of decrease of the reservoir pressure during the last few years was 0.2 bar per year, which is very small. From the most recent pressure build-up test, shut-in pressure there is higher in south-west of the production area and there is a steep pressure gradient from south-west to north-east. This suggests that there is a lateral steam flow from south-west to north-east in the reservoir and most of steam currently produced is supplied from south-west. M-7 which has the highest shut-in pressure and is one of the most south-western wells, produces the most steam and its rate of decrease over eighteen years is less than 1 t/h per year. These facts suggest that the Matsukawa geothermal reservoir still has enough potential to maintain its rated output, 22 MW.
From the chemical reservoir monitoring, steam produced at southwestern wells are richer chemically in old meteoric water, and poorer in younger meteoric water and volcanic gas compared with northwestern wells. It suggests that the chemistry of the steam Is controlled by local pressure balance.
Most of the steam currently produced at Matsukawa is dry superheated steam. Recently, the degree of superheat has become higher especially at north-eastern wells. Thus, re-injection of condensate is planned to support reservoir pressure and to maintain stable steam production.
A small-scale experiment has been conducted since March 1988, to assess its effect on steam production,
[2] Mineyuki HANANO: "Reservoir Engineering Studies at the Matsukawa Geothermal Field", Journal of the Geothermal Research Society of Japan, pp. 255-284, Vol. 16, No. 3 (1994)
Abstract:
Matsukawa was the first geothermal power plant established in Japan. It started power production in October 1966 and is the only vapor-dominated geothermal field developed to date. The power plant has been continuously producing full power, 22MWe, for almost 27 years. Matsukawa is located about 600km northeast of Tokyo and about 27km northwest of Morioka, Japan. It is in the Hachimantai volcanic region, one of the most active volcanic regions in Japan. This paper reviews reservoir engineering studies at Matsukawa. This includes a study of the current state of the reservoir studied mainly by pressure buildup tests, a study of the initial state of the reservoir studied mainly by reconstruction of a reservoir pressure profile, and a numerical modeling study of the natural state of the reservoir.
Continued pressure buildup tests since 1986 have revealed that there is a lateral steam flow from southwest to northeast in the Matsukawa vapor-dominated reservoir, and most of the steam is supplied from southwest of the development area. This result suggests that the vapor-dominated reservoir extends further southwest than the area now being exploited. These conclusions are supported by production records and chemical data of produced steam.
The study on the natural state of the Matsukawa geothermal reservoir has revealed that there was a thin vapor-dominated zone at the shallow part of the reservoir (around 300m to 400m depth) and the current production zone (800m to 1300m depth) was filled with liquid before exploitation.
Early production wells produced wet steam with some hot water at first, but they turned to produce only dry steam after a production period of 6 months to 1 year, because of the existence of low permeability aureole around the reservoir and high heat flow. Estimated conductive heat flux, 1.5W/m2 is as high as that of The Geysers.
The natural state modeling study showed that the model of the initial state of the reservoir, described above, was feasible. The results also indicated that the low permeability aureole was very important for the evolution of its natural state and also for production of superheated steam from the liquid zone below the thin vapor-dominated zone in the shallow part of the reservoir. Initial temperature distribution and the results of the simulation study suggest that there is an extensive heat source in the southwestern part of the reservoir.
[3] Tatsuya Kajiwara, Mineyuki Hanano, Takemi Ohmiya, Koichi Otanaka: “The Efforts for Sustainable Steam Production and Electrical Power Generation in the Matsukawa Geothermal Field, Japan”, Journal of The Geothermal Research Society of Japan, Vo. 26, No. 2, pp. 135-145, 2004, DOI: 0.11367/grsj1979.26.135
Abstract:
This paper reports successful operation of the Matsukawa geothermal power plant since 1966. This includes a summary of the production and electrical power records of the power plant. The wells and reservoir have shown a very slow decline, which is a result of appropriate station sizing and adequate operational criteria. The power plant was sized only to meet the demand of the company's factory for its in-house electric use, instead of full utilization of the resource. The power plant has been operated so as to maximize the profit instead of insisting on operating continuously at full power. A proper understanding of the reservoir based on some chemical and physical monitoring data has helped to maintain stable operation. Station sizing (23.5 MWe since 1993) appears to be the most important factor in the successful development and operation of the Matsukawa geothermal field.
[4] Jun Sato: "Overview of the Matsukawa Geothermal Power Plant," Journal of the Institute of Electrical Engineers of Japan (IEEJ), pp. 45–56, Vol. 87-11, No. 950, 1967.
[Translation to English: Chapter 1]
1. Background of Matsukawa Geothermal Development
In 1952 (Showa 27), when Matsuo Village in Iwate Prefecture began drilling in the Matsukawa area to develop hot springs, instead of hot water, they encountered an unusual eruption of steam. This marked the beginning of what is now the Matsukawa Geothermal Power Plant. Recognizing the potential of geothermal energy, Toka Kogyo—an enterprise mainly engaged in electric furnace operations for the energy-intensive ferroalloy industry—initiated a site survey in 1956 (Showa 31).
Since then, the company began foundational survey research in collaboration with the Geological Survey of the Industrial Technology Agency. In 1963 (Showa 38), with approval from the Science and Technology Agency, full-scale development began under a partial contract with the New Technology Development Corporation.
Regarding the production wells, drilling of Well No. 1 commenced in August of the same year, and by January of the following year, it yielded more steam than expected. Wells No. 2 and 3 were subsequently developed in succession.
Initially, the plan was to generate 5,000 kW of electricity. However, due to the unexpectedly high steam output from Well No. 1, the plan was quickly revised to 20,000 kW. Equipment planning was carried out between 1964 and 1966 (Showa 39–41), followed by construction from 1965 to 1966 (Showa 40–41), and eventually, test operations began in September 1966, with commercial operations starting in October of the same year.
[5] Mineyuki HANANO: “Success of the First Commercial Scale Geothermal Power Development in Japan; Matsukawa Geothermal Power Station”, Journal of the Mining and Materials Processing Institute of Japan (MMIJ), pp. 214-222, Vol. 33, No. 9, 2017.
Abstract:
The Matsukawa geothermal power station has been in commercial operation since 1966. its geothermal reservoir was discovered by chance, by drilling of hot spring wells by the local administration in 1952, Japan Metals & Chemicals (JMC) noticed this phenomenon and started exploitation for a geothermal power development in 1956. Then, JMC and Geological Survey of Japan (GSJ) started collaborative study in 1958.
The biggest technical challenge for success in Matsukawa was a decision of drilling target depth for steam production and a casing shoe depth to stop in-Row of shallow cold water. It was examined through measurements of water levels in three exploration wells, borehole temperature profiles and flow rates of rivers. Geological and geophysical studies by GSJ helped this study. Owing to this study, the Ist production well succeeded to produce dry steam in 1964 and ted to a success in the first commercial scale geothermal power development in Japan.
Supporting materials (supported formats: GIF, JPEG, PNG, PDF, DOC): All supporting materials must be in English, or if not in English, accompanied by an English translation. You must supply the texts or excerpts themselves, not just the references. For documents that are copyright-encumbered, or which you do not have rights to post, email the documents themselves to ieee-history@ieee.org. Please see the Milestone Program Guidelines for more information. Please email a jpeg or PDF a letter in English, or with English translation, from the site owner(s) giving permission to place IEEE milestone plaque on the property, and a letter (or forwarded email) from the appropriate Section Chair supporting the Milestone application to ieee-history@ieee.org with the subject line "Attention: Milestone Administrator." Note that there are multiple texts of the letter depending on whether an IEEE organizational unit other than the section will be paying for the plaque(s). Please recommend reviewers by emailing their names and email addresses to ieee-history@ieee.org. Please include the docket number and brief title of your proposal in the subject line of all emails.
