When it comes to refrigerator lighting there's many different variables out there. Basic refrigerators have incandescent bulbs. This is a 25 watt bulb that's placed at the top of the refrigerator. Some may be in the front, some may be to the rear of the refrigerator, but one thing to remember, incandescent bulbs use a lot of energy, but they also produce a lot of heat, and who wants heat in the refrigerator?
Let's look at refrigerators today that feature LED lighting. LED lighting is available in several different levels. Basic LED lighting, like incandescent lighting, will be placed just in the top of the refrigerator. The next level of LED lighting will be at the top as well as on the sides of the refrigerator. This is designed to give you a better view of those foods being stored down lower. The light in the top can't pass through three or four shelves if they're loaded with food, so that front lighting definitely helps.
Then you have ramp up LED lighting. With ramp up lighting, when you open the door, the lights will start dim and gradually increase to full brightness.