UPDATE 1 — El Salvador's Bukele says Spain's Cox Energy to invest $2.9 billion

(Adds investment details) SAN SALVADOR, Oct 13 (Reuters) — Salvadoran President Nayib Bukele on Tuesday announced a $2.9 billion investment by Spanish firm Cox Energy to develop energy, water, and fuel projects in the country. The package includes a $1.8 billion natural gas storage plant that would enable energy sales to other countries, along with solar energy, water and sanitation components. $600 million for water and sanitation improvements. $300 million for solar energy storage batteries, with a capacity of 440 megawatts and potential to expand to 1 gigawatt. $200 million will be invested to develop a photovoltaic plant. "This will directly benefit Salvadoran families," Bukele told reporters, adding that the benefits would materialize once a new power plant to be built by Cox becomes operational. (Reporting by Gerardo Arbaiza, Writing by Natalia Siniawski, Editing by Iñigo Alexander) ((mailto:natalia.siniawski@thomsonreuters.com;)