Do you need 2 Amp at 120V AC? If so you need a bigger generator (250 Watt)
Or if you need it at a lower Voltage then you should do a search for "off-line power supply". Even then you will still likely need more than 5 watt generator unless the Voltage you want is really small. Remember that Watts = Volts x Amps so for 5 Watts and 2 Amps, you can only get 2.5 Volts out.
