Office Buildings
In 2005, a total of 160.4 million square feet of office space was built in the United States. California leads with a total direct investment of just over $2 billion followed by Texas with $1.8 billion in direct spending.1 In fact, the commercial real estate sector has been a key driver in keep the U.S. economy going despite the nationwide housing slowdown. In a survey conducted by the Energy Information Administration (EIA), the West South Central census region, which includes Arkansas, Louisiana, Oklahoma and Texas, contained 84,000 office buildings or about 1,343 million square feet of office space.2

It has been estimated that as much as 30% of the energy consumed in office buildings is wasted.3 This suggests a significant opportunity for energy use reduction, cost savings, and the mitigation of greenhouse gas emissions through cost-effective energy efficiency opportunities, such as combined heat and power.

Across the United States, the average annual energy intensity for office buildings is 79.8 kBtu per square foot and the average cost is $1.65 per square foot. Of the total energy consumption, 66% is for electricity and 34% is for natural gas and other fuels. This translates to 15.5 kWh per square foot of electricity and 0.27 therms per square foot of natural gas.3


Space conditioning and lighting together account for 70% of all energy consumed in a typical office building, with an additional 20% of energy consumption used to power office equipment.3 The remaining energy is consumed by water heating, cooking, and refrigeration systems, as well as other miscellaneous uses.


There are many reasons why owners of office buildings should consider installing a CHP system. According to Mr. Charles Curtis of Northern Power Systems () there are three main factors:4

• Cost savings for the host facility or customer
• Reliability benefits above those provided by the existing utility grid
• The "green" factor - an ability to reduce the amount of air emissions contributing to global warming