UPDATE 1-Spain's Acciona gets shareholder approval for energy unit IPO

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MADRID, April 12 (Reuters) - Spanish engineering and energy group Acciona received shareholder approval on Monday for a stock market listing of its energy business, clearing the way for a deal to help fund an expansion of its renewables fleet and cut debt.

The company plans to list at least 25% of the renewable energy business, which could be among the biggest of a series of planned IPOs in the sector in Spain.

Acciona makes most of its money from generating and supplying renewable energy, which has become an increasingly popular sector for investors as governments and corporations try to wean themselves off fossil fuels and stem climate change.

Chief Executive Officer Jose Manuel Entrecanales, whose family controls around 55% of the company, has declined to say how much money he hopes to raise.

But with investor appetite high, bankers in the sector have suggested the whole business, which operates wind farms in the United States, Australia, Spain, Chile and Mexico, could be worth 10 times its core earnings of 831 million euros ($1.01 billion).

Some of the proceeds will go to nearly doubling overall capacity to 20 gigawatts (GW) by 2025. The company also hopes to get access to cheaper capital.

Spanish energy veteran Repsol is also considering a stock market listing for a new low-carbon business which operated around 1 GW of renewable capacity at the end of 2020 and has almost 12 GW more in its pipeline.

Power output varies between technologies and consumer needs differ across markets, but one megawatt can power about 1,000 U.S. homes on average.

Smaller developers Opdenergy and Ecoener have declared their intentions to list.

Acciona will also use some of the cash to pay down debt, which exceeded 4.2 times core earnings at the end of 2020.

Reporting by Isla Binnie; Additional reporting by Jesús Aguado; Editing by Mike Harrison