Am I right in thinking that the 'Repair' Energise card costs an action to play?
While the "Repair" Energize card is an "action card" (see page 23 of the rules), it does not require an action to play it. Calling it (and any of the other Energize cards) an "action card" in the rules was a daft idea.
Mind, the rules are clear on the matter, see page 23.
There is no limit to the number of Action Cards you can play on your turn, and playing an Action Card never costs you one of your actions for your turn.
Plus, playing such a card isn't listed an one of the possible choices under Actions on page 11.
There are ten different actions you can take:
• Visit sickbay
• Enterprise Attacks
• Either Beam down to the planet or Beam up to the Enterprise
• Move one space on the planet
• Make a Discovery (pick up token)
• Special character action
• Draw 1 Energize Card
• Transfer 1 crew member
• Attempt one Challenge