Jan 25 (Reuters) - U.S. renewable energy firm NextEra Energy Inc on Tuesday appointed insider John Ketchum as its new chief executive officer and narrowly beat quarterly profit estimates, helped by more businesses switching to cleaner energy sources.

Ketchum, former finance chief at NextEra and currently the head of its energy resources unit, will succeed Jim Robo as the CEO in March.

Shares of NextEra were down 4.1% at $78.56.

Eric Beaumont, analyst at Barclays, attributed the share fall to a "broad market sell-off and the announcement that Jim Robo, the CEO for the last 10 years, is stepping down in March".

Ketchum took over as president and CEO of NextEra Energy Resources in 2019, overseeing its largest three-year capital investment program and a near doubling of the unit's renewables backlog size, the company said. In NextEra's Florida Power & Light (FPL) division, its biggest by revenue, the average number of customers increased by about 82,000 in the fourth quarter from a year earlier.

In 2022, however, FPL's earnings growth is expected to be lower in the first half and higher in the next, the company said in a call with analysts.

NextEra's clean energy division saw a 25% quarterly fall in added capacity of renewables and storage projects to 1,500 megawatts (MW) from a year earlier.

Revenue for the three months ended Dec. 31 came in at $5.05 billion, well below market expectations of $6.25 billion.

Adjusted earnings rose nearly 4% to $814 million, or 41 cents per share, beating analysts' average estimate by a cent, according to Refinitiv IBES data.

The Juno Beach, Florida-based company raised its full-year 2022 adjusted earnings per share estimates to between $2.93 and $3.08, up from $2.77 to $2.97 earlier. (Reporting by Rithika Krishna and Arunima Kumar in Bengaluru; Editing by Ramakrishnan M. and Devika Syamnath)