On average, lighting accounts for approximately 10% of a restaurant’s overall energy costs.

You’ve heard it before: the standard advice for saving money on lighting is to replace incandescent lightbulbs with compact fluorescent or LED bulbs. Yes, that works, and yes, that’s a relatively small investment that can reduce your energy costs.

Even energy-efficient lightbulbs still cost money, though—so what about taking advantage of a free source of energy: the sun? In many restaurants, it’s possible to reduce interior lighting during the day and let the sun illuminate your diners’ meals.

Making natural lighting comfortable

The easiest way to use daylight is simply to open your curtains or pull up the blinds, and seat your patrons around the windows to take full advantage of daylight hours.

The main challenge of using daylight as lighting is the problem of solar heat gain—that “greenhouse effect” that happens when a window magnifies the heat from solar radiation. Since you want to cook your food, not your patrons, there are a couple of steps you can take to reduce solar heat:

  • Apply a UV-blocking film that’s appropriate for your climate to the window.
  • Install blinds that allow light through but block heat.
  • Add adjustable awnings to help block direct sunlight but still allow illumination

If you’re installing new windows, look for ones that have a high solar heat gain coefficient (SHGC) number—the higher the number, the more heat the window is able to block. Windows with a high solar heat gain can not only keep your customers comfortable, they can save you 13%-17% on your cooling costs.

No windows? Think about skylights and light tubes

In a lot of restaurants, the dining area is often the only space with windows. So how do you take advantage of daylight in the kitchen, or restrooms? Well, the simple answer, if it’s appropriate to your building, is to invest in skylights.

For some buildings, this is as simple as installing a few simple dome-style skylights. However, if you can’t afford the amount of roof real estate a dome skylight requires, if your roof placement isn’t appropriate, or if there are structural challenges, you might consider installing a tubular skylight, also called a sun tunnel or light tube. These long reflective tubes, which channel sunlight from the roof into your interior, tend to be smaller and less intrusive than traditional skylights.

Most tubular skylights maximize your daylight illumination by using a system of prisms and mirrors to refract and reflect sunlight through a tube into your space—meaning that, even if the sun is at an extreme angle in the sky, you’ll still be able to see. Tubular skylights tend to be less expensive than traditional skylights, offer better insulation, and can work well even in inner rooms like restaurant kitchens and restrooms.

Have you used daylighting techniques in your restaurant? Share your experience in the comments section.

Image credit: joelk75