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GEORGETOWN, Guyana, Jan 10 (Reuters) - Guyana's government on Friday signed a $526 million loan agreement with the U.S. Export-Import Bank (EXIM) to finance an energy project aimed at doubling the South American nation's power generation capacity and cutting oil imports.

Guyana is trying to take advantage of its vast offshore natural gas reserves and increasing production to secure enough power generation capacity for its fast-paced economic growth.

The project includes a gas separation plant, a 300-megawatt power plant, and a pipeline. The initiative is expected to reduce carbon emissions in the country by over 460,000 tonnes per year, according to the EXIM.

The agreement was signed in Georgetown by the bank's president, Reta Jo Lewis, and Guyana's finance minister Ashni Singh.

"This project will double the country's installed electrical capacity, providing cleaner, more reliable and more affordable energy for families and businesses," Lewis said.

The loan will support firms Lindsayca and CH4 Systems, which are in charge of building the project, with U.S. major ExxonMobil providing services.

Local environmental groups criticized the move, saying it contradicts U.S. President Joe Biden's commitments to phase out support for fossil fuels under international agreements.

(Reporting by Kemol King; Editing by Leslie Adler and Nia Williams)

((marianna.parraga@thomsonreuters.com; +1 713 371 7559; Reuters Messaging: @mariannaparraga))