NextEra Energy Inc (NYSE:NEE) shares are sliding in extended trading Monday after the company announced plans to sell approximately $1.5 billion of equity units. What Happened: NextEra Energy said it plans to sell equity units for $50 consisting of a contract to purchase NextEra Energy common stock in the future and a 5% undivided beneficial ownership interest in a NextEra Energy Capital Holdings debenture due Nov. 1, 2029. In approximately three years, the equity unit holders will be required to purchase NextEra Energy common stock for cash. Upon settlement, NextEra Energy will issue the requ…