During the day, Solatube systems use advanced optical technologies to capture sunlight, no matter the angle at which it arrives. At night, however, even highly effective skylights go dark—that is, unless you choose a Solatube Smart LED system. Here, built-in energy-efficient bulbs turn on automatically when light levels recede (at sunset, or in the event of cloud cover). That way, if you're cooking dinner, you can always count on the fixture to output effective lighting. You'll only need one fixture to illuminate the entire room!