I believe that the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory has a Petawatt class laser for it's fusion experiments. Lawrence Livermore had another one before that was shut down in the late 90s. I believe that when dealing with this class of lasers that the duty cycle is probably fairly long and that the laser doesn't fire with very high frequency. I could be wrong though.
LLNL had a Petawatt class laser that they shut down in 1999. I am under the impression that NIF would be at or near Petawatt class when it is done, but it could be the total of the 192 beam lines that gives that power.