Commercial buildings in the United States are getting larger and more commonly include energy-saving features like LED lighting and occupancy sensors, according to the U.S. Department of Energy’s 2018 Commercial Buildings Energy Consumption Survey (CBECS), published in September 2021.
The CBECS is a survey conducted roughly every five years by the Energy Information Administration at the DOE. A large sampling of buildings are used to generate data that is then extrapolated for national estimates covering a wide range of building characteristics, such as region, activity, size, age, and equipment.
What does the data tell us about the estimated 5.9 million commercial buildings in the United States?
Building snapshot
From 2012 to 2018, the estimated number of U.S. commercial buildings grew by 6%, while total floorspace grew 11% to 97 billion sq.ft. An estimated 357,000 buildings were built 2013 to 2018, representing 7.5 billion sq.ft.
The number of education, lodging, warehouse, public assembly, worship, and service buildings increased, while some markets, such as office, healthcare, food sales/service, and mercantile, decreased. By floorspace, the largest markets were office, mercantile, warehouse, and education.
The South (Census region) had the largest population of commercial buildings, followed by the Midwest. The West came in third while populated by buildings of the largest median size. The smallest population of buildings and the oldest in median years resided in the Northeast. A total of 86 million people worked in these buildings, with a median 1,175 sq.ft. per worker, 14% more space than in 2012.
Seventy percent of commercial buildings were 10,000 sq.ft. or smaller, down from around 75% in 2012. For all buildings, the median building size was 5,400 sq.ft. Buildings over 100,000 sq.ft. represented 2.4% of the total building population but 34% of the floorspace.
Lighting and controls
The 2018 CBECS reveals a remarkable technological shift toward LED adoption at the expense of traditional lighting. In 2018, standard fluorescent lighting covered 76% of commercial building floorspace, a decline from 92% in 2012. Incandescent declined from 44% to 22% and HID 27% to 12%. LED, meanwhile, increased from 25% to 64% of floorspace, installed in 2.6 million buildings, more than five times more buildings than in 2012.
Lighting controls adoption also increased, with occupancy sensors making the most gains. In 2018, occupancy sensors were installed in more than 1 million buildings controlling more than 44 billion sq.ft., 26% more buildings than in 2012 and 24% more floorspace. In 2018, occupancy sensors controlled lighting in 17% of all commercial buildings but 46% of all commercial building floorspace.
Daylight harvesting modestly increased from 7% to 7.5% of floorspace, increasing from 6.1 to 7.2 billion sq.ft. in 138,000 buildings. Building automation systems for lighting increased from 14% to 17%, increasing from 12 to 16.7 billion sq.ft. in 317,000 buildings. Light scheduling remained flat at about 35% of floorspace. Multilevel lighting and dimming similarly remained flat at about 15% of floorspace, which is somewhat surprising due to the inherent controllability of LED lighting and suggesting some dimming for energy management perhaps was not covered in the responses. For the first time, the CBECS included plug load control, which showed use in less than 1% of buildings and around 2% of floorspace in 2018.
A simple conclusion here is that the majority of buildings and floorspace remain untapped for lighting automation.
Similarly, there remains a persistent lighting upgrade opportunity. These upgrades are most attractive for buildings with older lighting systems, which tend to overlight spaces using obsolete technology. Add long operating hours and high energy rates, and the building may be a good candidate for a lighting upgrade.
The 2018 CBECS estimated the median age of all commercial buildings to be 36 years and that about 2.7 million buildings (46% of all buildings), constituting 39.8 billion sq.ft. (41% of all floorspace), were built before 1980. CBECS estimated that 2.4 million of these buildings, representing 25 billion sq.ft., have not received a lighting upgrade. Interestingly, CBECS also reported a significant amount of floorspace illuminated by LED—24.9 billion sq.ft.—suggesting at least piecemeal upgrades, such as exit sign replacements and installation of LED linear replacement lamps, have occurred.
Mine the data
Overall, the 2018 CBECS offers a plethora of information that can be used for rich insights into the commercial buildings market. How many education buildings are in the Northeast, and what’s their median age? What’s the total floorspace of office buildings built before 1990, and what’s the average per worker? CBECS has an estimate for these and many other questions.
Note, however, that the results are estimates based on a sample population. It’s also important to view the results with an educated eye to interpret some of the results and to remember that how some data appears depends on how the question was interpreted by both DOE and the respondent.
Check out the 2018 CBECS, available free in a series of tables, here.
Leave a Reply