Outlets should be a functional part of the kitchen island without drawing attention to themselves. The codes vary from state to state but an outlet or two is typically required on an island depending on the island’s overall size. In your design, consider the color, placement, size, and shape of the outlets. Numerous options allow outlets to be integrated into the island without compromising the beauty of the design.  There are ready-made outlets available at big box stores like Home Depot and Lowes in standard colors. However, if you have a specialty finish on your island, companies like AmerTac have a wide offering of unfinished wood outlets that you could have your cabinet provider paint/stain to match.