For example, at 250 watts, mean lumen output per watt over the useful life of the lamp is 58 for
MH vs. 87 for HPS; in other words, HPS produces 50% more mean lumens per watt. Even at 70
watts, mean lumen output is 45 for MH and 64 for HPS; in other words, HPS produces 42%
more mean lumens per...