Below is a recent contribution to tED Magazine. Reprinted with permission.

In November 2017, the U.S. Department of Energy (DoE) released its new 2015 U.S. Lighting Characterization report. The 135-page report, which follows similar reports issued in 2001 and 2010, estimates the total installed lighting stock in the United States by light source and building sector. Dense with tables and graphs, it provides data useful for business planning while clarifying trends.

In 2015, lighting consumed 17 percent of all energy used in the United States. Accounting for 37 percent of energy, the commercial sector was the biggest lighting energy user, followed by outdoor and residential. The residential sector, however, had the most lamps—an estimated 6.2 billion out of a total of 8.7 billion, or 71 percent. Most of the lighting stock added since 2010 was in this sector. At 2.1 billion lamps, the commercial sector ranked second (24 percent).

The report confirms and helps quantify several significant trends recognized in the lighting market during the time period:

LED enjoyed rapid growth.
LED penetration increased from nearly 70 million lamps, or 1 percent of the lighting stock, to about 700 million lamps, or 8 percent, in 2015. Adoption was greatest in the outdoor sector (23 percent), followed by the commercial (10 percent), residential (7 percent), and industrial (4 percent) sectors. This trend is currently accelerating.

Incandescent lamps declined. Obsolescent, highly regulated incandescent lamps declined from 45 percent of the total lighting stock in 2010 to 25 percent in 2015. The installed base of incandescent lamps declined 40 percent.

Halogen enjoyed big growth.
While overall, traditional technologies saw little growth in installations from 2010 to 2015, halogen got a big boost by offering a compliant alternative to incandescent general-service A-lamps being phased out. Halogen’s share of the installed lighting stock increased from 4 percent in 2010 to 12 percent in 2015, with installations increasing from 28 million to 693 million, an increase of 350 percent.

Linear fluorescent saw flat growth.
While compact fluorescent lamps increased from 19 to 26 percent of the lighting stock from 2010 to 2015, linear fluorescent stayed at about 2.3 billion lamps, with various winners and losers among the category’s subgroups. Four-foot T8 lamps, for example, gained 38 percent, while obsolete, highly regulated 4-ft. T12 lamps declined 30 percent.

HID saw flat growth. HID lamps also stayed at about 140 million lamps. Metal halide was the sole winner, increasing 11 percent, while high- and low-pressure sodium suffered small declines. The installed base of obsolete, highly regulated mercury vapor lamps, meanwhile, declined 68 percent.

Efficiency is increasing. The net effect of all this was steadily growing average lighting efficacy. National average lighting efficacy increased from 39 to 51 lumens/W between 2010 and 2015. From 21 to 28 lumens/W in the residential sector, 62 to 86 in commercial, 78 to 90 in industrial, and 73 to 80 in outdoor.

Lighting controls show modest adoption.
Adoption of lighting controls is about 18 percent in the commercial sector, including occupancy sensors (10 percent), energy management systems (5 percent), multi-strategy systems (1 percent), timer-switches (1 percent), daylight-responsive controls (1 percent), and dimmers (1 percent). In the residential sector, 11 percent of lamps, the majority controlled by dimmers.

Overall, the report indicates that between 2010 and 2015, lighting in the United States underwent a phase in an ongoing major technological shift to highly energy-efficient light sources, with accelerating emphasis on LED. To get the full report, available as both a PDF and XLS spreadsheet, click here.

Inventory, energy consumption, and lumen production in 2015 by building sector. Image courtesy of the U.S. Department of Energy.

Average lighting efficacy by building sector for 2001, 2010, and 2015. Image courtesy of the U.S. Department of Energy.