• Fluorescent light bulbs are three to four times more energy efficient than incandes cent fixtures. How Much Money Can You Save by Replacing Old Light Bulbs with Fluorescent Ones? First, you’ll save by using less energy to light your home. How Much Money Can You Save by Replacing Old Light Bulbs with Fluorescent Ones? Fluorescent, halogen, and xenon are the main choices of light bulbs. Fluorescent light bulbs offer consumers a significant isn't nearly as remarkable as the electric cost savings. Compact fluorescent light bulbs use less energy, last longer and cost less to use than standard incandescent bulbs--and they are good for the environment. Fluorescent light bulbs consume significantly less energy than their incandescent counterparts while giving off about the same amount of light. Fluorescent light bulbs are no longer only long tubes that take fixtures that once were the sole domain of incandescent light bulbs. What else should I look for when buying ENERGY STAR light bulbs?