Yonden Engineering Co., Inc.

Yonden Engineering Co., Inc. (四電エンジニアリング株式会社) is a Japanese engineering company based in Takamatsu, Kagawa Prefecture, and a member of the Shikoku Electric Power Group. Founded in 1970, the company has built its business around the construction, maintenance, and inspection of power generation and substation facilities, supporting the stable supply of electricity that underpins daily life in the Shikoku region and beyond. Over more than five decades, Yonden Engineering has grown into what it describes as a "comprehensive engineering company." Its work spans mechanical, plant, electrical, nuclear power, information and communications, and civil engineering and construction fields. The company handles projects from initial surveys and design through fabrication, construction, and ongoing maintenance. Its six technical divisions—mechanical, plant, electrical, information and communications, nuclear power, and civil engineering and construction—allow it to respond to a wide range of customer needs. While its roots are in the electric power sector, Yonden Engineering serves a broad customer base that includes private companies in power, gas, water, petroleum, chemicals, steel, paper, information and communications, construction, transportation, food, and finance, as well as public-sector clients such as local governments. In recent years, the company has expanded into renewable energy, undertaking wind power, solar power, and biomass power projects across Japan, in line with its long-term commitment to regional and social development. The company marked its 50th anniversary in 2020. Its corporate philosophy is expressed in three principles—"Sincerity, Creativity, and Cooperation"—and it continues to pursue technical improvement and productivity as it positions itself for future growth. Recent activities include the completion and start of commercial operation of a storage battery facility in Ishikari, Hokkaido, announced in 2026, reflecting its involvement in efforts toward carbon neutrality by 2050.

Yonden Engineering Co., Inc. was founded in 1970 as a member of the Shikoku Electric Power Group. From its inception, the company's core mission has been to support the stable supply of electricity essential to daily life, primarily through the construction, maintenance, and inspection of power generation and substation facilities for the Shikoku Electric Power Group. Over the following decades, the company leveraged the technical expertise gained from power facility construction to expand into adjacent fields. It developed capabilities in energy, information and communications, environmental services, civil engineering and construction, and industrial plants. By handling projects from survey and design through construction and maintenance, Yonden Engineering established itself as a "comprehensive engineering company." The company organizes its technical capabilities into six divisions: mechanical, plant, electrical, information and communications, nuclear power, and civil engineering and construction. These divisions have accumulated experience over 50 years, enabling the company to respond to diverse customer needs. In 2020, Yonden Engineering celebrated its 50th anniversary. The company's corporate philosophy is built on three principles—"Sincerity, Creativity, and Cooperation"—which guide its management and its commitment to customer trust, employee development, and technological improvement. In recent years, Yonden Engineering has expanded its focus to renewable energy, undertaking wind power, solar power, and biomass power projects across Japan while maintaining its base of operations in the Shikoku region. The company has also pursued energy storage projects; in 2026 it announced the completion and start of commercial operation of a storage battery facility in Ishikari, Hokkaido, framed as a contribution to the realization of carbon neutrality by 2050. The company continues to operate as a subsidiary within the Shikoku Electric Power Group, serving a wide range of private and public-sector clients across Japan.

• 2020

  Celebrated 50th anniversary.

• 1970

  Company founded as a member of the Shikoku Electric Power Group.

• Organizational restructuring and changes to executive titles announced.

• Organizational change at subsidiary Ei Wind Power Generation Co., Ltd.

• FY2025 financial results summary and executive personnel changes announced.

• Completion and start of commercial operation of a storage battery facility in Ishikari, Hokkaido.

Comprehensive engineering company providing reliable technical services across energy, industrial plant, information and communications, and civil engineering fields.

• Engineering, procurement, and construction (EPC) for power generation and substation facilities

  Construction and maintenance services for power generation and substation facilities, primarily for the Shikoku Electric Power Group.

• Plant engineering

  Design, fabrication, construction, and maintenance of industrial plants.

• Electrical and lighting systems

  Electrical and lighting system engineering services.

• Information and communications systems

  Information and communications system engineering services.

• Nuclear power-related engineering

  Engineering services related to nuclear power.

• Civil engineering and construction

  Civil engineering and building construction services.

• Renewable energy projects

  Wind, solar, and biomass power generation projects across Japan.

• Manufacture and sale of soft drinks

  Manufacture and sale of soft drinks.

1. 1四電エンジニアリング株式会社yon-e.co.jp
2. 2会社案内 | 四電エンジニアリング株式会社yon-e.co.jp
3. 3ご挨拶 | 四電エンジニアリング株式会社yon-e.co.jp
4. 4パンフレット | 四電エンジニアリング株式会社yon-e.co.jp
5. 5Yonden Engineering Co., Inc. (Japan) - Wikidatawikidata.org