LED downlights are directional lamps that focus virtually all of their light downward from a recessed can fixture mounted in the ceiling. They may be self-contained lamps with integral drivers (similar to ballasts) that can be retrofitted into existing can fixtures, or dedicated fixtures designed to use LED technology from the start. Various trim kits are available to match existing décor. LED downlights are available in a warm white color that is comparable to the traditional incandescent lamp. Lamp life is listed as 25,000 to 50,000 hours, as compared to 3,000 hours for incandescent products. Many LEDs are dimmable. Products are available in a variety of beam spreads, wide to narrow. The directional nature of LEDs makes them great candidates for this application because no light is wasted by bouncing around inside the fixture. The potential for heat build-up in the fixture is an issue that must be dealt with by using properly sized and designed heat sinks, or LED life can be dramatically shortened. With 12W to 15W LED retrofits replacing 65W incandescent lamps, energy use is substantially reduced and less heat is generated. This can save additional energy in spaces that require cooling, but increases heating load and costs. A number of products in this category are listed on both the Energy Star Qualified Products for Residential LED and the USDOE LED Lighting Facts product list.

Recessed ceiling lighting is the most commonly installed lighting fixture in residences. The fixtures are very cheap and the incandescent lamps typically used are inexpensive. They are designed to use reflector-type lamps, but are often seen with standard light bulbs or compact fluorescent spiral lamps. Downlights using traditional lamps are inefficient, with only about 50% of the light produced making its way out of the fixture. Because they have a limited distribution pattern, multiple recessed downlights are needed for general ambient lighting, controlling a significant amount of wattage with one switch. Recessed downlights are also used singly for task lighting or to highlight a feature such as an alcove or artwork.

Traditionally, halogen incandescent lamps have been installed in residential downlights. Many are controlled by dimmers, allowing light levels to be dimmed to a low level with a warm, orange glow. The heat build-up in the cans and the potential for air leakage to the attic above have prompted energy codes to specify gasketed fixtures and special insulation practices to prevent heat loss from the living space. Recently, some compact fluorescent reflector products have achieved good light output and dimming capabilities for these applications.

LED downlights are readily available in stores and online in rapidly increasing quantities. Cree first introduced the LED downlight with their LR6 model in 2007 at the DOE Solid State Lighting Research and Demonstration workshop. Dimmable LED downlights are now available through retailers including Home Depot and Lowes.

Commercial LED downlights have made good penetration in the market, and more and more products are becoming available for the residential sector.

The April 2013 LED Lighting Facts Product Snapshot (US DOE, 2013) showed significant maturity in both performance and availability of LED downlights. As of June 2013, over 700 LED downlights are listed in the LED Lighting Facts database. Nearly 80% of the currently listed downlights meet the ENERGY STAR® efficacy criterion for downlight luminaires. The majority of downlights have a nominal correlated color temperature (CCT) of 2700 K or 3000 K and a color rendering index (CRI) greater than 80. This warmer light reflects more prevalent use in residential and light commercial applications. Many are intended to replace halogen-lamped luminaires.

LED luminaires promise long life, and their robust design reduces lamp replacement costs. Environmental benefits include no mercury content, so disposal issues are reduced compared CFLs. LED “white” light is available in a range of color temperatures. LED sources are inherently controllable, and do not experience life degradation with frequent switching. Because no ultra-violet (UV) or infrared (IR) light is emitted to damage products or artwork, LED lamps can be particularly well-suited for retail areas and museums.  Lower lighting energy use also decreases the space cooling load and costs. 

High first cost has been the most significant barrier; however, prices are dropping dramatically. As of October 2014, a variety of LED downlights are available through big box stores at prices from $25 to $50, with $35 - $40 being typical.

Compatibility with existing dimmers may be a concern because not all products work with all dimmers. Point-of-purchase demonstrations of dimming quality and quantity could help allay concerns of prospective purchasers. Clear labeling that indicates which products are compatible is also important.

In many homes, recessed lighting includes multiple lamps so there can be a significant expense to retrofit a whole room at once.

Incentives to buy down the cost could help the proposed technology gain traction in the residential market, as can clear information on product selection and good warranty service.

Products that compete with the proposed technology include: 

• Halogen PAR, which have replaced most of the incandescent reflector lamps as a result of 1992 EPACT
• Halogen infrared reflector lamps
• Compact fluorescent reflector lamps
• Potentially the very new Electron Stimulated Luminescence (ESL) lamp

These products are compared in Table 2.2 – PAR, BR and R Shaped Lamp Installed Base, from Energy Savings Estimates of Light Emitting Diodes in Niche Applications, USDOE, page 13. (EERE, 2011 Pg 13) Test results shown in the webcast, “CALiPER Round 11 Testing,” (Paget, 2011, Pg 25) for Round 11, show that the LED product exceeds the halogen IR reflector lamp performance in light output and efficacy.