A survey of 87 retailers conducted by Pacific Gas & Electric found many are unhappy with their lighting and are considering LED lighting to save energy. But, at the same time, they lack sufficient information to evaluate products.
PAR lamps, such as PAR38 and PAR30, are popular for accent lighting because they create contrast, focusing light emission in a single direction. Available in a variety of beam spreads, they offer retailers a lot of flexibility. Creating what they often refer to as “punch,” retailers reach for “spot” lamps when lighting key displays, and “narrow flood” and “flood” lamps to layer in bright fill lighting or create great wash effects. Trading halogen for suitable energy-saving LED PAR lamps can reduce ongoing energy costs by up to 80%, resulting in savings that fall to the bottom line, like net profit.
Determining if LED replacement lamps in PAR trackheads or downlights can do the best job possible is somewhat reliant on observing mock-ups. It’s difficult to qualify such a visual product from published common bid specifications, including lumens, wattage, beam angle, efficacy and rated service life.
Retailers may be less familiar with the overlap in beam classifications across manufacturers, and noticeable light pattern variations exist between PAR halogen and LED products with “the same” nominal light output (lumens), beam angle and field angle.
A better approach to evaluating similar lamps and capturing more subjective qualities (such as beam characteristics and color quality) is to benchmark options with a scorecard comprised of the following elements:
• Field angle and spill light
• Lamp appearance
• Fit and compatibility with other lighting
• Color quality (natural colors/complexion, vividness)
• Appearance of white light (CCT (Kelvin))
By evaluating the lamps against these factors, a retailer can better verify aesthetics, which increases confidence and project value.
For example, suppose a retailer wanted to use a PAR lamp to highlight a necklace on a mannequin, with the light spanning its shoulders. The retailer then goes on to compare two different PAR lamps with the same lumens and beam angle. Since catalog data shows Lamp A has higher beam intensity (CBCP) than Lamp B, the end user anticipates Lamp A will be the better, brighter product of the two.
However, the reality is Lamp B provides the best overall impact and coverage in this scenario. The reason is because Lamp A has a lower field angle, and it’s actually the light contained within the field angle that is producing the less-than-desired effect of lighting the shoulders. In other words, beam angle and CBCP data don’t portray a complete picture of light distribution from directional lamps.
Likewise, the spacing of PAR lamps that accent vertical displays throughout a sales floor and around the store perimeter relies on field light.
Although successful display lighting depends on the appeal of displays, ambient lighting and proper focus of accent lighting, field angle is an example of something that is important and easily observed. But it is rarely captured about products in competitive project bids.
With lasting light intensity and high color quality, qualifying PAR LED lamps means energy reduction strategies do not have to deteriorate highlighting.
When evaluating PAR lamps, retailers should ask vendors about how their products meet the factors on the scorecard as opposed to just top-level facts that look good on paper. In doing so, there is a better change that the lighting will meet the retailer’s real-world goals, and also save a lot of time in the process.
Sally Lee is retail market segment manager at OSRAM SYLVANIA.