There are good reasons why cruise lines have low-wattage hairdryers and no alarm clocks in staterooms.
High wattage electrical devices are fire hazards. They can overheat and start fires.
High wattage electrical devices easily exceed the capacity of the step-down transformers that supply 120 volt power to your stateroom. If too many high wattage devices are used in certain areas of the ship, the transformers can fail, causing a blackout, or overheat and possibly cause a fire.
Cruise lines tried for years to place alarm clocks in staterooms.
They were always stolen by the passengers.
We gave up.
Use the wake up call system, or bring your own.
Note that some older ships still operate on 50 cycle current. A 120 volt alarm clock running on 50 cycle current will lose 10 minutes every hour.