Bret Mattes | Founding Secretary
Yayasan Tunas Hijau Lestari

Dr. Bret Mattes is an energy and sustainability professional with more than 40 years of international experience across renewable energy, power, oil & gas and forestry. He spent almost three decades with major energy companies including Shell International and BHP Billiton before moving to Indonesia in 2006, where he has held senior executive and board positions including President Director of Star Energy and senior advisor to Pertamina on new and renewable energy. Today, Dr. Mattes is Founder of Yayasan Tunas Hijau Lestari, a sustainability-focused foundation, a partner of PT Numada and Senior Renewables Advisor to the United Nations Office for Project Services. He also serves as Chairman of the Alliance of Low Carbon Businesses in Indonesia. With extensive experience across both conventional and renewable energy as an investor and developer, Dr. Mattes brings a unique technical, commercial and strategic perspective to the global energy transition, with particular expertise in Indonesia and ASEAN.