No, metal halide and fluorescent light systems do not produce more energy than they consume over the course of their lifetime when left on continuously.
Both metal halide and fluorescent light systems are types of discharge lamps that require electricity to operate. These lamps work by passing an electric current through a gas or vapor to produce light. In this process, some energy is lost as heat and other forms of energy.
Although metal halide and fluorescent lamps are more energy-efficient compared to traditional incandescent bulbs, they still consume more energy than they produce. The energy efficiency of these lamps is measured by their luminous efficacy, which indicates how much light they produce per unit of electrical power consumed.
While metal halide and fluorescent lamps are relatively efficient in converting electrical energy into light, they still have energy losses due to factors like heat dissipation, power supply inefficiencies, and internal resistance. These losses prevent them from producing more energy than they consume.
It's important to note that energy cannot be created or destroyed; it can only be converted from one form to another. Therefore, any light source that operates on electricity will consume more energy than it produces.