There is a mission, "Place an Energy Plant" which asks players to build an energy plant. But if you have already placed it, prior to receiving the mission, the mission cannot be completed.
We are aware of players who can't complete the mission because the built Plant isn't recognized.
Yesterday (11/15) we pushed a fix that should have auto-completed the mission when an Energy Plant is present on your home turf. Please let us know if this fix hasn't let you complete the Mission yet.
Thanks for your patience!
--The Mafia Wars 2 Support Team