Power fragments were small purple stones that existed in prehistoric times. Scattered across the island by meteors millions of years ago, the fragments contained powerful energy. They played a major role at the Prehistoric Party 2016, where the need to travel back in time in order to collect them to power the UFO at Area 501 was what started the party.
In order to collect the fragments, players needed to dig them up in the game Dino Dig, similar to the way dinosaur eggs were collected during the 2013 and 2014 Prehistoric Parties.
According to Gary in issue 535 of the Club Penguin Times, the fragments were somewhat combustable.