How many lumens does a 1000W metal halide produce?

A standard 1000W metal halide lamp puts out roughly 90.000 to 115.000 initial lumens right after striking the arc. But here’s what the spec sheets don’t shout about: that number drops fast. Within the first 100 hours, you lose about 15–20%. By the time it hits 40% of its rated life (around 8.000 hours for most probes), you’re looking at 60.000–70.000 lumens. That’s a 40%+ drop before the lamp even fails. The ballast type matters too—magnetic probe-start versions sit on the lower end (90k–100k), while pulse-start and electronic ballasts push closer to 110k–115k. But those initial numbers? Marketing gold. Real-world performance? Different story.

Compare that to a 1000W metal halide’s actual usable light over time, and you’ll see why facilities dump them. That “100k lumens” claim assumes a brand new lamp, clean reflector, and perfect voltage. After six months of daily 12-hour runs, you’re down to maybe 75k lumens. By year two, you’re replacing bulbs not because they’re dead, but because you can’t see what you’re doing. For reference, a good 400W LED high bay matches or beats that worn-in metal halide’s output while pulling 60% less power. So when someone asks “how many lumens,” the real answer is: enough to blind you on day one, then a slow fade into disappointment