Fundamentals of Lighting Cost Analysis
Although lighting performance characteristics are the most important factor in the selection of a lighting system, cost is nearly always a consideration. Often, when the lighting performance of different systems is similar, cost becomes the deciding factor. Thus, accuracy and uniformity in cost analyses by different individuals may be readily and fairly compared.
Of course, cost comparisons exclude considerations of relative lighting quality, which is of equal importance to quantity. Reports showing favorable economy for a lighting system which fails to provide comparable comfort should be accompanied by suitable explanations.