The present invention provides a power and regasification system based on liquefied natural gas (LNG), comprising a vaporizer by which liquid motive fluid is vaporized, said liquid motive fluid being LNG or a motive fluid liquefied by means of LNG; a turbine for expanding the vaporized motive fluid and producing power; heat exchanger means to which expanded motive fluid vapor is supplied, said heat exchanger means also being supplied with LNG for receiving heat from said expanded fluid vapor, whereby the temperature of the LNG increases as it flows through the heat exchanger means; a conduit through which said motive fluid is circulated from at least the inlet of said vaporizer to the outlet of said heat exchanger means; and a line for transmitting regasified LNG.