120v or 130v incandescent bulbs
I've heard that 130v will tend to last longer but will produce less light output. One source says 130v bulbs are only 70-80% as bright as 120v bulbs. I can believe this, but the numbers on the manufacturers' spec sheets don't tell the same story. A Phillips 130v 65W BR30 reflector flood (248849) is rated at 635 lumens. A similar 120v bulb (248765) is rated at 640 lumens. Nearly the same brightness. What gives?
Here's my theory: The 130v bulb makes 635 lumens at 130v, and the 120v makes 640 lumens at 120v. Each bulb consumes 65 watts of power at its rated voltage. The trouble is, the specs don't tell you what the 130v bulb looks like at 120v. According to hearsay, it's 20-30% dimmer. But... I would expect it to consume less power too. It's not using 65 watts to produce 70-80% as much light... it's using, say, 55 watts. Sure, it would be somewhat less efficient than the 120v bulb in terms of lumens/watt, but not that much less efficient. Right?
I hate light bulbs. All light bulbs.