Can you tap a rune to add energy to your pool at the start of turn, recycle that same tapped rune for power cost, and still use the floated energy from that rune later in the turn?

Ruling: Yes, you can exert a rune to add energy to your pool, then recycle that same tapped rune to generate power for another card, and still use the floated energy later in the turn. The rune pool persists throughout your turn and only empties after you draw for turn and at end of turn.

Sequence:

• Tap a rune to add energy to your pool
• Recycle that tapped rune to pay for a card's power cost
• The energy remains in your pool to spend later in the turn

Nuances:

• This is a major difference from Magic: The Gathering - you maintain a bank of energy for the entire turn since there is no specific order/phase structure to a turn
• The rune pool empties at two specific times: after you draw for turn and at end of turn