Tetsuya Nishigaki (preferred name: Nishi) is the President of Diamond Generating Corporation (DGC). He is responsible for setting and executing DGC’s growth strategy, with an emphasis on Business Development and Power Solution Services, as the company adapts to changes in the power sector.

Nishi joined Diamond Generating Corporation in April 2025 after spending the majority of his career at Mitsubishi Corporation, primarily in the oil and gas industry. Over nearly three decades, he held a variety of leadership roles in Tokyo, Perth, London, and other key global energy hubs. His expertise includes LNG marketing, upstream oil and gas asset development, project management, and strategic planning—working closely with partners and stakeholders across Asia, Oceania, and Europe.

With this diverse background, Nishi brings a cross-sector perspective to the power industry, supporting the DGC's efforts to navigate the ongoing energy transition.