In energy resources, hydrogen: the form of energy released from the nucleus, the core of atoms which is made up of protons and neutrons [Section 4(x), DOE Department Circular No. DC2024-01-0001, Providing a National Policy and General Framework, Roadmap, and Guidelines for the Hydrogen in the Energy Sector]
In nuclear energy: any form of energy released in the course of nuclear fission, nuclear fusion or any other nuclear transmutation [Section 5(z), Philippine National Nuclear Energy Safety Act of 2025]
Note: Under the Philippine National Nuclear Energy Safety Act of 2025, the term is written as “Nuclear energy”. Moreover, the term is alternatively referred to as atomic energy [Section 5(z), Philippine National Nuclear Energy Safety Act of 2025].