EVALUATION OF ECONOMIC EFFICIENCY OF MODERNIZATION OF ARTIFICIAL LIGHTING OF EDUCATIONAL INSTITUTIO

Abstract

The analysis of technical characteristics and cost of modern light sources and motion sensors used in administrative premises is carried out. It has been established that lighting of corridor-type rooms using LED panels of the lower and middle price ranges with a luminous efficiency of 80-85 and 100 lm/W, accordingly, becomes less expensive in the second year of operation compared to fluorescent lighting. Installation of panels with a higher luminous efficiency, up to 120 lm/W, at the current level of prices on them has certain risks, as the payback period of the investment in this case is about 7 years, exceeding the warranty period of these panels. The payback period of investment in the automation of lighting control in corridor-type rooms using relatively inexpensive infrared motion sensors and the expected reduction of energy consumption by 30% does not exceed 5 years, demonstrating the feasibility of this event. Measures for replacing fluorescent lamps with LED panels in less loaded classrooms, up to 510 hours of operation per year, have a payback time of 4-6 years, which exceeds the warranty period of the panels. Therefore, according to the authors of the article, it is appropriate to first replace the lamps in the corridors, and then, after accumulating experience in operating the purchased light sources, to replace them in the classrooms. Due to their high cost in the premises of educational institutions, the use of presence sensors as well as automated lighting level control systems is not economically feasible. The urgency of saving energy by replacing fluorescent lamps with LED and automation of lighting control, due to the trend towards an increase in the cost of electricity, will also grow. The algorithms and formulas given in the article for determining the present value, payback periods are simple and can be applied to other types of light sources and design conditions.