Monday, June 21, 2010

Illumination in Stadiums - Introduction

A stadium comes to life when its fully packed to capacity and all its luminaries are working properly. Illumination in stadiums is a very important topic when it comes to the design phase of construction. The manner in which the luminaries are going to be installed impacts the overall performance of the stadium and not to forget the game being played. A well lit stadium/Arena ensures maximum illumination and minimal glare to the fans both on the pitch as well as on the seats. The lamps should be of correct rating to avoid unwanted glare and loss of heat through radiation. To achieve this, powerful luminaries are placed on top or even mounted on special masts at a height distance to reduce heat radiating to the fans and also making sure that maximum light falls on the pitch in the stadium. Less powerful  luminaries are then installed near the pitch to provide light for live television and quality photography.
All these lamps together with those inside the stadium present a power thirsty load to the power supply source. Today’s stadiums are supplied by up to 5 transformers and dedicated substations just to reduce power outages.

Facts & Figures
  A regular world class world cup stadium has a total power rating of up to 1.47MW consisting of 26,000 fluorescent lamps each having a lifespan of 8,000hrs, 4,250 individual lamps and a total area lit of 25000(meters sq.).Lamps are placed before an asymmetric parabolic mirror ensuring maximum illumination of each floodlight lamp. Total consumption can be in the range of 506KWh when fully lit. Total electricity for the stadium is supplied be 5 Transformers.Over 100km of cabling is required to interconnect these luminaries so that they light in uniform.

The cost of designing, purchasing, installation etc. of luminaries is very high. I cannot state figures at this instant but the costs are well above thousands of dollars. This is because they are of high quality and have a long life and also the quantity required. Stadium floodlights are priced according to rating and technology of the lamp filament. Some are so fragile that touching the inner lamp renders the lamp unfit for use. The service life of these luminaries ranges from 8,000-10,000hrs of around 6hrs per day.

Laws & Regulations
FIFA has outlined regulations that should be followed in the design  in of luminouries in a stadium to match world standards. No match is to be staged in a stadium that has not met these regulations. The following information is extracted from the FIFA document: TECHNICAL RECOMMENDATIONS AND REQUIREMENTS FOR THE CONSTRUCTION OR MODERNISATION OF FOOTBALL STADIA    19.3 Lighting
    For all matches to be played in the evening, the entire surface of the playing area must be evenly lit, with a mean minimum lighting level of 1200lux
    In addition, emergency lighting should be available in case of power failures, which would ensure at least  21/3 of the above named lighting level on the playing area.
    A backup power supply should be available in case of power failures in order that all public areas retain an acceptably safe standard of lighting, that the match may continue and television coverage may go on uninterrupted.
Worth Noting
One of the characteristics of lights used in stadium illumination is the required ‘dead time’ between being switched off and being ready for reuse which is of the order of a 7-10min.In addition to this cool down period, the light can take several minutes after being switched ON before they reach full illumination. In the event of a dip or momentary outage causing the lights to trip and reset, the game could be interrupted for 10-15min.

1 comment:

  1. In this environmentally conscious age, yellow incandescent lighting era silently fades into the oblivion. Even the fluorescent mix has to fight for survival. There is electroluminescence of light emitting diodes everywhere. It illuminates. It is used in visual signals. It acts as a light sensor. It facilitates most of the interacting and measuring processes. Miniature size, low energy need, low maintenance, high-efficiency, high frequency of blinking and economic sustainability has made it a light-emitting darling of the century.

    In an incandescent light bulb, an electric current heats a wire filament. The glowing filament emits energy capsules of light known as photons. In fluorescence, electric current excites atoms of mercury vapor. Invisible ultraviolet light is absorbed by a phosphorescent material such as Zinc Sulfide, which then emits radiation that is visible to the human eye. Light emitting diodes work on the principle of electroluminescent. Electronic excitation of material such as gallium arsenide emits photons. Changing the precise composition of such material by doping, the frequency and hence the color of emitted light can be changed. It is a junction of two semiconductors hence is the name diode. The current flows across the junction to cause electronic excitation causing the material to illuminate.

    Mark from Electrical Engineering