Our commercial building of 1001 thousand square feet and about 1100, T-8 three bulb parabolic troffer fixtures is coming up on 10 years old. We have re-bulbed three times and are coming up on the fourth. The existing ballasts are Advance PEL-3P32-RH-TP, 277V, 60Hz, .32A and have been to this point, remarkably dependable. Does anyone have any experience with ballast longevity in the ten year + range ? We have a number of options: 1) Re-bulb as-is and hope that the ballast don’t fail before the next re-bulb. 2) Re-bulb and re-ballast as existing. 3) Retro-fit to 2 bulb T8 conversion with new reflectors and ballasts to eliminate one bulb. Numbers two and three will most likely fall into the capital expense category and there by saving 1100 trips up and down a ladder that option number 1 will involve since we can’t use a lift in most of theses areas. The conversion to T-5 has been ruled out as too expensive. So, in your opinion(s) should we be concerned about the ballasts’ life at this point? Are new ballasts appreciably more efficient that what we have now? Will it be cost effective to replace them all versus an as- they -fail senario? I’m interested in all view points. I’m hearing what appears to be some pretty tall tales from various lighting manufacturers about “energy savings”. In a perfect world, what would our power consumption be on a single three bulb fixture with the ballast listed above, with three 28 watt bulbs running for one hour? Are we consumint 28 watts x 3 for one hour or .32 A for one hour?