A Look at Office Buildings
Are they on multibuilding complexes?
How do they use energy and how much does it cost?
How do they use energy and how much does it cost?
Although office buildings have the second largest amount of buildings and floorspace, they consume the most energy of all building types, accounting for 19 percent of all commercial energy consumption (see total energy figure on home page). They use a total of 1.0 quadrillion Btu of combined site electricity, natural gas, fuel oil, and district steam or hot water.
Electricity is the predominant energy source used in office buildings, the reasons for which are discussed in the next section, "How do they use electricity?".
Site electricity is the amount of electricity consumed within the building; electricity use can also be expressed as primary electricity, which includes the energy consumed in generating and transmitting electricity. Office buildings used 2,039 trillion Btu of primary electricity, which brings the total energy consumption for office buildings up to 2,383 trillion Btu, or 23 percent of total primary consumption for all commercial buildings.
Energy use is distributed among a number of different uses in office buildings. Lighting accounts for the most use, followed by space heating and office equipment.
Office buildings use an average of 1.4 billion Btu per building and have an energy intensity of 97.2 thousand Btu per square foot. This intensity slightly exceeds the average for all commercial buildings (90.5 Btu per square foot). (See total energy per square foot figure on home page.)
Large (over 50,000 square feet) office buildings use energy more intensively than smaller buildings; they also pay less per unit of energy, possibly because higher consumers of energy are offered better rates by their utilities.
Table 4: Major fuel consumption and cost by size category
Of all the commercial building types, office buildings have the highest total expenditures for energy—$15.8 billion per year—most of this for electricity. The energy expenditures in office buildings account for 23 percent of energy expenditures in commercial buildings.
On average, $1.51 per square foot is spent on energy in office buildings, more than the national average for energy usage in commercial buildings ($1.19 per square foot).
Forecasts
The Office of Integrated Analysis and Forecasting (OIAF) uses CBECS data to make commercial sector energy use projections. For estimates of commercial building consumption (and floorspace) from 1998 to 2020, see Table 22 of Supplement Tables to the AEO2000.
Continue: How do they use electricity?
Go to "How do they use energy and how much does it cost?" for other building types:
Specific questions may be directed to:
Joelle Davis Michaels
joelle.michaels@eia.doe.gov
CBECS Manager
Phone:
(202) 586-8952
FAX:
(202) 586-0018
URL: http://www.eia.doe.gov/emeu/consumptionbriefs/cbecs/pbawebsite/office/office_howuseenergy.htm
Release
date: September 11, 2000
File last modified:
January 3, 2001