UPDATE 3-Acciona targets valuation of $10.5 bln for its energy unit

(Adds details of demand for the offer, books closed)

MADRID, June 29 (Reuters) - Spain’s Acciona is targeting a valuation of 8.8 billion euros ($10.47 billion) for the listing of its renewable energy unit after marketing the deal at the lowest end of its original range, the company said in a statement on Tuesday.

Acciona trimmed the price of shares in Acciona Energia, its most profitable unit, to 26.73 euros per share from an initial range of 26.73-29.76 euros, the statement, published on market supervisor CNMV, said, confirming an earlier Reuters report.

The offering consists of 49,387,588 shares, or 15% of the company, plus 15% of the over-allotment option, listing up to 17.25% - down from initial plans to list up to 25% of the energy unit, plus 15% of the greenshoe option, which would have meant listing up to 28.75% of Acciona Energia.

Acciona said in a separate statement that the demand from institutional investors rose to 3.6 billion euros, or 2.4 times the final offer decided, as recommended by the global coordinators for the IPO.

Spurred by a global drive to reduce planet-warming carbon emissions, Acciona plans to use the proceeds to add to a renewable generation fleet currently dominated by wind farms in the United States, Australia, Spain, Chile and Mexico, by 2025.

Following a record number of stock offerings at the beginning of this year, some of which performed poorly on the market, investors have appeared fatigued and some IPO candidates cancelled their plans.

In the 2021 ranking of major IPOs in Europe, this would still come close to the 7.6 billion pounds ($10.58 billion) valuation achieved by British online food company Deliveroo , and below the 12.1 billion euros by Vodafone’s infrastructure unit Vantage Towers.

Acciona Energia is expected to start listing on the Madrid stock market on July 1.

At 26.73 euros per share, Acciona will raise around 1.32 billion euros from the 15% sale, in what would still be the largest IPO in Spain since mobile phone mast operator Cellnex debuted in May of 2015. Taking into account the greenshoe option, that could rise to 1.52 billion euros.

$1 = 0.8400 euros Reporting by Arno Schuetze, Jesús Aguado and Inti Landauro; additional reporting by Victoria Waldersee; editing by David Evans and Aurora Ellis