Hook up a light designed for car into a wall socket or battery source
You simply need a plug-in AC/DC converter (transformer) of 12-28 volts that provides enough current for the 54 watt consumption. 

Divide 54 watts by the voltage of your selected transformer to calculate the amperage draw, and allow a 30% buffer or so. For example, 54 watts / 12 volts = 4.5 amps, so you'd want a transformer that provides at least 6 amps or so. The higher the transformer's voltage, the lower the current draw. 

The power bar has a simple wire pigtail for connection, so you'll need to use appropriate crimp connectors or some other safe, insulated method.