Utility giant NextEra Energy (NEE 1.57%) has reportedly made a huge bid for Duke Energy (DUK -0.12%) that could shake up the utility sector if accepted, although the offer was rebuffed, according to a report Tuesday by The Wall Street Journal.

Duke Energy is the largest regulated utility in the U.S., with a market capitalization of $60.6 billion. NextEra Energy has a market cap of nearly $138.6 billion, making it the world's largest utility owner.

The Journal reported that NextEra is still interested in pursuing the deal, but added that "there is no guarantee NextEra will do so, and if it does, that a deal would result."

The combination of the two would create an electricity and gas utility behemoth with a customer base exceeding 14 million. NextEra operates in Florida; Duke has operations in Florida, the Carolinas, and the Midwest. In 2019, NextEra generated $19.2 billion in revenue; Duke Energy had $22.8 billion in revenue.

King chess pieces on wooden blocks with mergers and acquisitions text.

Image source: Getty Images.

This development reflects NextEra Energy's insatiable hunger for growth. On Tuesday, the company announced it'll acquire GridLiance Holdco and GridLiance GP from The Blackstone Group for roughly $660 million, including debt. GridLiance operates more than 700 miles of transmission lines and other infrastructure spread across six states.

NextEra is a large traditional utility and the world's largest producer of wind and solar energy. Earlier in September, the company announced a 4-for-1 stock split while raising its midterm outlook and projecting 6% to 8% growth in adjusted earnings per share for 2022 and 2023 and 10% growth in its annual dividend through 2022.

Duke Energy plans $56 billion in investments over the next five years, 4% of which will be targeted at commercial renewables. It has increased dividends for 14 consecutive years.