Sponsored by the Illuminating Engineering Society of North America (IESNA), Lightfair International 2013 convened at the Philadelphia Convention Center from April 21 to 25, drawing more than 23,000 attendees and exhibitors who showed off an array of light sources, materials, electronics, and luminaires. Following is an overview of trends and key observations gathered at the show.

Solid-state lighting is quickly becoming the preferred light source (much faster than predicted). User acceptance of LED lighting in form factors from retrofit lamps to innovative new fixture designs fitted with digital control systems that are capable of providing dimming and color change features were front and center on the show floor. Not surprisingly, lighting's new frontier appears to be the ability of the LED chips to deliver the exact color and luminance level desired by an occupant, using a wired or a wireless control network, a hybrid of the two, or a power-line control scheme.

It looks like short-range wireless communications are poised to dominate the field, allowing LED lighting to be set up with a simplified plug-and-play activity. The latest versions of sensors, analytic chips, and refined controls will make this happen. Other trends included: daylight harvesting, bi-level control, wider choices in power switching, distributed intelligent control, simplified programming for quicker start-up, and easier integration with a building monitoring system. Basically all of these features and technologies revolve around the mantra of energy savings.

Connecting sensors with building loads and wireless communications offers many benefits, but often the benefits are negated by the poor performance and initial cost of proprietary, non-standard protocols. This situation is no longer true, since two wireless communications standards are emerging as standouts: the ZigBee Commercial Building Automation standard (part of the ZigBee Alliance) and the EnOcean Alliance. The ZigBee Alliance created two new standards to serve lighting applications: LightLink and ZigBee IP. Based on the IEEE 802.15.4 standard for personal area networks, ZigBee uses the 2.4 GHz band and adds extra layers to the protocol to implement a wireless mesh network, which can be integrated into a wired BACnet system. Samsung showed a starter kit using ZigBee-based retrofit lamps, and the company is seeking an entry point into the networked home business using devices such as occupancy sensors, Internet-enabled TV, appliances air conditioning systems, security systems, and door locks, all of which can be enabled by a smartphone.

The EnOcean Alliance wireless control standard emerged from a proprietary product developed by EnOcean GmbH, which, in 2001, was spun off from Siemens AG, as a provider of self-powered wireless lighting controls. Subsequently, the alliance produced the ISO/IEC 14543-3-10 standard. Firms such as Hubbell Building Automation, with its wiSTAR wireless control line, and Leviton use the Alliance license-free 902 MHz frequency.

Vendors showing lighting products using WiFi included Philips, with its SpaceWise technology, Hubble Building Automation, with its wiHUBB self-healing mesh network, WattStopper, and the Lighting Science Group. Kim Lighting showed the Lightvault 8 in-grade fixture with Bluetooth wireless capability for commissioning (i.e., setting a dimming level and aiming the luminaire using a Bluetooth-enabled smartphone).

Proprietary control systems are still valid, and a number of vendors have developed communications system around Lutron's EcoSystem controls, which connect to the firms' line of wired and wireless systems as well as other building protocols, such as BACnet. In addition, the company's Quantum Total Light Management System unifies all lighting controls, automated window shades, sensors, digital ballasts, and LED drivers under one system. New control interfaces incorporate slider controls, architrave keypads, and software features like conditional logic, user access rights, and iPad apps. Both indoor and outdoor luminaires from Lumenpulse will be imbedded with the EcoSystem, and Lumenpulse's power line communications technology, called Lumentalk, can carry Lutron's digital lighting control commands.

Vendors also showed roadway and outdoor LED luminaires, fitted with occupancy sensors along with high-density mesh (HDM) wireless control systems, which can capture and transmit information from the surrounding environment for a variety of applications and services, such as luminaire maintenance, public safety, weather monitoring, parking management, and retail analytics. GE's LightGrid can place network connectivity and a GPS receiver atop every street luminaire in a municipality for rapid commissioning.

Philips, Osram Sylvania, Kenall, and others have outdoor roadway and parking garage LED luminaires with integral wireless dimming control. Lithonia Lighting's D-Series parking garage fixture is available in two options, each offering three color temperatures and multiple control choices. Lighting Science Group offers the Forefront high bay luminaire, which features a modular optical design and three beam distributions; a similar product is designed for exterior applications and available in multiple beam distributions. Toshiba’s TLS-R TL LED roadway luminaire with a 100,000-hr life can replace 70W to 400W HID lamps.

For use in a variety of exterior monitoring applications, Hubbell Building Automation’s WASP2 Dimming Outdoor Occupancy Sensor provides 0VDC to 10VDC (Class 1) output for the control of LED, fluorescent, and HID fixtures. Dipswitches can set unoccupied and occupied dimming levels. Suitable for temperatures down to -40°C, the unit also offers daylight sensing and interchangeable lenses for field masking.

As for color changing, Acuity Brands Lighting's Aera recessed LED luminaire from Winona can alter the color of light to mimick the natural variations of sunlight throughout the day and sync to circadian rhythms. Intended for wall mounting above eye level, similar to a clearstory window, the system is a series of 6-in. or 8-in. square units recessed into the wall. Each fixture delivers both white task lighting on a desk and tunable-color ambient lighting using red, green, and blue (RGB) LEDs. White-tunable products from the Gotham, Veil, and Mark Architectural Lighting brands are also available. These and other Acuity brands use four wireless systems: ROAM outdoor mesh, nWiFi indoor wireless, Adura indoor mesh network, and Remote Device Management (RDM) indoor point-to-point wireless technologies. Users can now alter lighting and sync indoor illumination to match the time of day. In collaboration with Marvell and Osram, Sharp demonstrated its Full Semblance White Light System in a 6-in. downlight, with a variable a CCT from 2,700K to 5,600K, using wired or wireless control. USAI offers its Color Select technology, and other firms have similar products.

The Juno Lighting Group's Indy LED Chroma Control luminaires use a hyperbolic reflector and offer tunable white, color tuning, and black body dimming features. The CT-Series allows changes in color temperature or color saturation and hue of a single or group of luminaires via a remote device. NexLight showed its line of low-voltage and line-voltage PerfectSense occupancy sensors, which feature integrated daylight sensors, walk-through mode, and auto-adapting technology.

Increasingly, LED luminaires are taking advantage of being pinpoint light sources by using edge-lit, thin profile flat panels to distribute the light evenly over the entire panel surface, while achieving up to 95% efficiency. GE showed the expansion of its line of blade-thin, edge-lit Lumination LED suspended and recessed luminaires, now available in five series. Philips' Bold Play suspended and wall-mounted luminaires use MesoOptics and light guide technology. Cooper Lighting’s Metalux Encounter and SkyRidge recessed ceiling luminaires use a Wave-Stream flat panel (edge lit technology), which eliminates LED pixilation and the need for diffusers. Cooper will use this technology for a number of fixture lines with striking shapes and forms as well.

Another line of GE fixtures that takes advantage of the LED source is the ABHX-Series fixture line from the recently acquired Albeo Technologies. Aimed at the industrial and commercial market, the modular luminaire is scalable from 6,000 lumens to 80,000 lumens and offers field changeable optics, power supply, and LED modules.

Manufacturers that previously offered throw-away solutions for LED luminaires are building fixtures with replaceable components, as is witnessed by the number of Zhaga Standard-compliant LED light modules that can reduce both unnecessary cost and risk in luminaire selection.Hubble Lighting's Kurt Versen line goes a step further with its MultiSource recessed downlight, which accepts remote phosphor LED, PAR LED, MR-16 LED, and metal-halide sources, as well as future sources, using modular connectors. Each light source has its own optical assembly, assuring beam performance and brightness control.

Osram Sylvania increased its portfolio of products within the EMerge Alliance, which is supported by more than 100 members and promotes the inclusion of 24VDC power distribution within a building, thus avoiding unnecessary transformations between AC and DC power. Other firms with registered products include Philips Electronics, Acuity Brands-Lithonia Lighting, and TE Connectivity.

Retrofit kits that replace the "guts" of existing T12, T8, and T5 recessed fluorescent troffers, or downlights, with an LED source were seen throughout the show. Leviton showed its expanded Zipline modular fluorescent retrofit kit with integrated prewired driver and LED strips that adhere to the fixture housing. Max Lite's RKT series recessed troffer retrofit kit is a similar product. Philps' EvoKit achieves energy savings without sacrificing looks and quality. Lighting Science Group introduced the Glimpse indirect recessed retrofit kit, offering the equivalent output of a 65W halogen lamp, and Osram Sylvania showed a number of downlight replacement solutions.

While LEDs were the darlings of the show, attendees did not overlook the improved performance of other sources, such as fluorescent and metal-halide system ballasts. Electronic fluorescent systems can provide up to a 60,000-hr rated life, and the ceramic metal-halide source can offer savings over halogen with CRI greater than or equal to 95, according to Venture Lighting. Osram Sylvania showed a fluorescent lamp, rated for up to 84,000 he, and a ballast with dimming function can be used for maximum savings. The Pentron HO nominal 4-ft fluorescent provides a 45,000-hr life with a lumen maintenance of 93%.

The variations in design of LED retrofit lamps show no sign of abating. At the same time, these LED replacement bulbs are approaching mainstream commodity status, with Cree, Philips, and other firms announcing price lists in the $12 to $15 range. American Illumination showed a GU24 direct replacement for a 13W CFL lamp.

Silicones are evolving to meet the growing need of the LED lighting industry regarding the increasing light flux and thermal loads, because they can be used in light guides, lenses, diffusers, and remote phosphor diffusers. For that reason, Dow Corning — traditionally thought of as an industry chemical company — showed its optical moldable silicones.