Dirk Morgna was locked overnight in a nuclear reactor by embittered scientist Dr. Zaxton Regulus as revenge for his being fired by Dirk's father. Dirk survived the ordeal and gained the ability to create and channel heat and light energy.
As per the Lightning Twins, I gave him a version of Kumano's damage ability and a variation of Pilgrim of Justice's ability. He also gets a mana fixing ability.
I didn't realize Sun Boy had not been posted until I was getting ready to post Sun Emperor...mistake rectified!