KDDI Open Innovation Fund V Invests in Starlight Engine―A Company That Aims for the Social Implementation of Fusion Energy

July 15, 2026

KDDI CORPORATION

KDDI invested in Starlight Engine Ltd. (Headquarters: Heiwajima, Ota-ku, Tokyo; CEO: Kiyotaka Kikuchi; hereinafter "Starlight Engine"), a company researching and developing fusion energy plants and driving forward a fusion power generation demonstration project, through KDDI Open Innovation Fund V (operated by Global Brain Corporation; hereinafter "KOIF V"), which aims to incubate new business co-creations with promising venture startups.

Recent years have witnessed a worldwide endeavor for carbon neutrality as we entered the age of AI, driving a surge in global energy demand.
Fusion energy is the process of replicating on earth the energy production process powering the sun by combining two atomic nuclei of a light element such as hydrogen to produce massive amounts of energy. The fuel resources for this energy production process are abundant, enabling a stable power supply regardless of the weather or time of day. As such, fusion energy is gathering global traction as the future of clean energy that does not emit CO₂ during energy production.
Even in Japan, the Japanese government recognizes the importance of fusion energy as a key energy security strategy within its framework for "Strategic Investment against Potential Crises" and "Growth-Oriented Investment," and is working together with the private sector to accelerate the pathways towards the demonstration of fusion energy power generation in the 2030s [1].

In contribution to these efforts, Starlight Engine is advancing "FAST" [2], an integrated demonstration project aimed at commercializing fusion energy. The FAST project's efforts incorporate each step in the process towards achieving this, from power generation demonstration to the construction of commercial fusion energy plants, and it aims to start with achieving fusion energy power generation demonstration in the 2030s in accordance with Japanese government objectives.

Through this investment, KDDI will utilize the assets of the KDDI Group, including telecommunications and AI computing platforms, to support the social implementation of fusion energy and contribute to the realization of a sustainable society.

As a "company that inspires passionate challenges," KDDI will continue to promote business co-creation through investment in promising startup companies, and create new business models together with customers and partners.

MUGENLABO Magazine
Fusion: From National Projects to Industry. Starlight Engine's Role as the "Implementation Hub" (in Japanese only)

(Reference)

• ■Overview of Starlight Engine

  • (1) Company name

    : Starlight Engine Ltd.

  • (2) Headquarters

    : Distribution A Building, AW1-S, Tokyo Ryutsu Center 6-1-1 Heiwajima, Ota-ku, Tokyo

  • (3) Date founded

    : April 2025

  • (4) Business activities

    : Research and development of fusion energy plants, and promotion of the "FAST" fusion power generation demonstration project

  • (5) Representative

    : CEO Kiyotaka Kikuchi

  • (4) URL

    : https://sle.energy/

• ■About the KDDI Open Innovation Fund

  KDDI Open Innovation Fund is a corporate venture fund that supports a broad range of venture companies. Through investments in startups with the potential to become the foundations of our new businesses in areas such as AI and Deep Tech, KDDI will continue to explore new business opportunities that will serve as our next pillar of growth.

• [1]

  Prime Minister's Office of Japan, "Comprehensive Economic Measures for Reiwa 7 (2025): Realizing a 'Strong Economy' through Strategic Investment against Potential Crises and Growth-Oriented Investment" (in Japanese only)

• [2]

  Abbreviation of "Fusion by Advanced Superconducting Tokamak." Project led by Starlight Engine to demonstrate fusion energy power generation in the 2030s.