When does Floating Energy and Power Clear?

According to the Riftbound Core Rules (Rule 166) and the provided RiftJudge FAQ #4873 and #7050, each player's Rune Pool empties at the end of each of the following times:

1. After the draw phase (for each player).
2. At the end of each turn (during the Expiration Step of the Ending Phase).

When the Rune Pool empties, any unspent Energy or Power is lost (Rule 166.1).