** NextEra's shares down 3.5% at $79.99 in extended trading after unveiling capital raise plans ** Utility co to sell $1.5 bln 3-yr mandatory convertible equity units at $50

** Each unit to consist of contract to purchase NEE common in future and 5% undivided beneficial ownership interest in a NextEra Energy Capital Holdings Inc debenture due Nov 1, 2029

** Expected net proceeds of $1.45 bln to fund investments in energy and power projects, other general purposes, including partial repayment of commercial paper obligations

** JP Morgan, Mizuho and Goldman Sachs active bookrunners for offering, which is slated to price overnight/before market open Tues, according to deal terms sheet seen by Reuters

** Deal being marketed with 2.5% annual distribution rate and 25% conversion premium, per terms sheet

** NEE on Mon closed up 1.8% at $82.87 for ~$170 bln market cap ** Last week, co reported $40 mln loss due to higher interest payments, and said considering possible restart of its nuclear power plant in Iowa while renewable deals swell

** YTD, stock up 36% vs S&P 500 Utilities index's ~28% advance and S&P 500's 22% rise

(Reporting by Lance Tupper and Shankar Ramakrishnan Lance Tupper is a Reuters market analyst. The views expressed are his own) ((lance.tupper@thomsonreuters.com lance.tupper@tr.com 1-646-279-6380))