Did you also know that the metal halide bulbs need to be changed at certain intervals of burn time? As the bulb goes through cycle after cycle of on off on off the lumens decrease at a particular rate. Not only is the lumens or brightness of the light diminished, it subsequently takes more and more energy to light the bulb. Each bulb has a lumens chart with the output after so many hours of operation. The pulse start MH lights have a much better rating than the old ballast / capacitor setup. I did not believe that the MH bulbs would actually take more and more energy to start and be kept lit until my electrician showed me just how much a fixture with a brand new bulb uses compared to a fixture with a bulb let say was 3 years old. I would wait until the bulb would actually burn out or blow up before I would change them. Even though the bulbs can be expensive, changing them at certain intervals and not waiting for them to burn out saved me a considerable amount of money in the long run. This also helps the longevity of the ballast / capacitor. Oh, one more thing, if you have a fixture that has a bad bulb and you continue to feed power to it, the ballast will continue to try and start the bad bulb and waste even more energy.