Our industry has seen the most dramatic changes in light sources over the last few years since the invention of the incandescent lamp (household lightbulb) by Joseph Swan, the English scientist. Contrary to popular belief, Thomas Edison, the American inventor, did not invent the lightbulb. While Edison was also developing an incandescent lamp at the same time as Swan, it was Swan who completed it first, as Edison couldn't figure out how to create a vacuum in the lamp. Edison eventually teamed up with Swan to form the Ediswan Lightbulb Company, allowing him to use Swan's technology. Edison focused on the bigger picture by developing generators to power New York City with electricity so that his invention could be used.
LED lightbulbs have now advanced to the point where they are becoming viable replacements for regular household lightbulbs. We thought now would be a good time to review the current market and make some predictions for the future.
LED – The State of Play
The biggest market for LED lightbulbs is as a replacement for mains voltage halogen GU10 spotlights. In fact, 77% of the market for replacement LED lightbulbs consists of GU10s. Most manufacturers now offer a 5.5-6W LED bulb that is the same size as its halogen equivalents, dimmable, and provides the same light output as a 50W halogen bulb, approximately 350 lumens. Some manufacturers now have excellent ranges of LED golf ball bulbs, LED candle bulbs, and LED household bulb replacements. Companies like Megaman and Philips are leading the way, offering a wide variety of lamp caps, including SBC, which some manufacturers have ignored. Overall, LED light sources have progressed well.
LED – The Future
One of the most exciting developments in LED technology has been the use of gallium nitride (GaN) as a substrate material. Using GaN as a substrate prevents fissures, allowing electrons to flow freely through the LED material. As a result, the lamps generate less heat and produce more lumens per watt used, increasing efficiency.
However, the cost of LED light sources remains the biggest barrier to entry. While the architectural and industrial markets are adopting LED light sources, the price point is still too high for widespread adoption in the larger domestic market.
Incandescent Lightbulbs
The phasing out of non-reflector incandescent lightbulbs was completed in September 2012, referred to as DIM1, which was supposed to mean that all regular lightbulbs with a wattage of 15W or greater are no longer available. However, this has not been entirely the case. The strong consumer preference for incandescent sources has led some innovative lamp manufacturers to produce rough service or industrial replacements to meet market demand. Sales of incandescent lamps at Lamps-on-line.com have not been affected by EU legislation, as most customers still prefer incandescent lightbulbs.
In January, I visited the Interiors exhibition at the NEC and noticed that every single decorative manufacturer of light fittings was using incandescent or halogen lamps in their fixtures. Representatives from these manufacturers explained that complying with the EU directive would negatively impact their fixture sales, as their clients demand incandescent lightbulbs. I also visited a SuperDry store in January to review their lighting and was surprised that one of the most popular clothing brands in the UK did not use any LED lightbulbs in their store (except for two LED projectors in the shop window). When I inquired, I was told that SuperDry has a particular preference for incandescent bulbs as they create a warm appearance that enhances the store's ambiance, which is more important to them than energy savings, despite the long hours their lights are on.
Summary
Incandescent lightbulbs are here to stay. LEDs have a place in our industry where energy saving is paramount and initial cost is less of a concern. However, they will compete more with CFL (compact fluorescent lamp) energy-saving types rather than incandescent lightbulbs. LEDs as retrofit lightbulbs to replace fluorescent tubes, HID lamps, and non-ballasted compact fluorescents are unlikely to happen. Fluorescent tubes are cost-effective and energy-efficient, making them the best option for office and public area lighting. HID lamps, such as CDMT and HQI-TS, provide a level of brightness that LEDs cannot match, have a long lifespan, and are more affordable than their LED counterparts.
