Abstract
| Electric lighting accounts for 19% of electricity consumption worldwide and generates remarkable concern to get energy savings. As a modern source of light, LEDs open up a multitude of innovative lighting solutions. LEDs lighting is already widely used in many niche areas like traffic lights, car lights, lighting displays, TVs etc. Now, based on lowered manufacturing costs, they penetrate into the general lighting market. But for specialists, LEDs are not yet the end solution in any lighting application. There are a lot of factors that can influence their adoption decision.Among them, the most favorable and promising one is the high efficiency, with values in permanent increasing. The paper discusses various aspects of LEDs efficiency and demonstrates that luminous efficiency is not a relevant criteria for a decision, a better understanding being got with an indicator like the Lighting Power Density, in W/m2. And beyond the efficiency, the paper makes a critical analysis of other parameters that matters in the lighting decisionmaking process, like lifetime, color rendering and chromatic shift, health and environmental impact. Finally, the paper point out that the calculation of cost and return of investment represent a very technical effort, based on accuracy of the entry data, often unknown by the investor itself, like different confidential costs, daily average time of functioning, temperature hazards and lifetime in condition of poor quality of electricity. |
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