The energy required for lighting in a particular space depends on a number of factors. These factors include the amount of lighted floor space, the hours of lighting, the illumination level (illuminance), and the effectiveness (efficacy) of the lighting equipment. A useful starting point in the analysis of lighting energy requirements is therefore to characterize commercial floor space with respect to these factors. Because lighting power and energy requirements depend on the product of these factors, it is important to consider them in combination as well as individually.
What this means is that the type and level of lighting must be pertinent to the shop type and the specific activity; be it highlighting for display or for the counter or be it a walkway or an escape route. Also not forget the emergency lighting element.
The world seems to have been taken over by LED lighting and it is only now in a position whereby it is both effective and economical. The savings in chargeable electricity are of the region of 60% and with added charges relating to the amount of carbon being used about to be increased it is essential to say why not change over rather than why. As a very general rule of thumb, and this means not using either the most or least expensive light fittings one can expect to have the cost paid back out of the savings in less than two and a half years.
But wait. there is even better news due to the government backed green scheme there are cheap loans available that allow for repayments to be made from the effective savings. So it seems that one can have one’s cake and eat it.