With Specialist’s Opinion
Dr. Nesrin Colak
Illumination Is A Prestige and A Creative Element.
80% of our perceptions are provided visually. For this purpose, the illumination is necessary firstly to implement any visual functions. Any illumination implemented by considering any physiological and psychological effects creates a comfort ambiance. The illumination is a prestige and safety incentive fact through a visual effect it creates other than them.
When the fact that share of the illumination is between 20% and 25% within total consumed electrical energy is considered, it is seen that any illumination system is not only evaluated based on illumination criteria, but its environmental extent is critical at least as much as such illumination criteria. As known, the Turkish Power Efficiency Code was published and became effective in the Official Gazette dated May 2007 and numbered 25610.
Goal of the Turkish Power Efficiency Code is to increase efficiency in use of power and power sources for purposes of using power efficiently, preventing waste, attenuating burden of power costs upon economy and protecting the environment. Power efficiency implies “reduction of power consumption without causing reduction life standard and service quality at the buildings and of production quality and volume at industrial facilities”. Energy resources should be used at highest efficiency bylaw at all stages from protection to consumption of energy resources. The Turkish Power Efficiency Code shall include the Power Performance Regulation, norms, standards, minimum performance criteria, information collection and control procedures on architectural design, heating, cooling, thermal insulation, hot water, electrical installation and illumination at the buildings. A “power identity certificate” shall be issued for each building. As a result of any sanctions imposed by this regulation, it is in evitable to evaluate the illumination system more carefully and submit any efficient solution at the existing buildings and new buildings to be built. Reduction of consumption costs, other factors and energy efficiency imposed bylaw should be applied carefully for illumination. Efficiency of the illumination systems should be evaluated at two stages: installed power and power consumption.
1. Illumination Load: Total installed power of the system installed for illumination.
2. Illumination Power Consumption: Total power consumed for illumination at the building. We can minimize the illumination load and utilization time and thus provide an efficient illumination without depriving any illumination standards.
The illumination load of a building may be reduced by using any efficient light sources and illumination devices. Of course, while any projects are prepared to reduce the illumination load, the illumination criteria should never be omitted. But, it is not sufficient to minimize the illumination load of the building only by efficient elements. Assuming that consumed energy (E) is power (P) times time (t), it is seen that reduction of utilization time of artificial illumination is critical at least as much as minimizing the illumination load for the system to be efficient. E[Wh]=p[w]x t[h]. It is possible to reduce utilization time of the illumination system only when the lights are turned off at times, when they are not used. It is possible to reduce utilization time of the systems without depriving comfort only at times, when they are not used in spaces and the daylight is utilized.
The researches shows that the lights are not turned off due to wide visual adaptation ability and unawareness at unnecessary times. Therefore, it is possible to reduce utilization time of the illumination only by automatic illumination control. Using any appropriate automatic control elements or systems for physical and use characteristics of the space, consumed electrical energy at the illumination may be reduced up to 60%. As a result, it is possible to minimize the utilization time by controlling the system illuminated by efficient illumination elements depending on daylight, on whether any person exists or not in the space or on time.