Morteza M. Ardehali, - Department of Energy System Engineering, KN Toosi University of Technology, Iran Iowa Energy Center, Iowa, USA
Theodore F. Smith, - Department of Mechanical and industrial Engineering The University of Iowa, USA

Because buildings consume in excess of one third of end-use energy in the U. S., the U. S. Department of Energy (DOE) and U. S. Environmental Protection Agency (EPA) have designed and promoted several programs for the purposes of increasing energy efficiency in the building sector. An EPA study in 1999 showed that the site energy intensity of Energy Star labeled building was 44 percent lower than that of average commercial buildings. While substantial energy efficiency has been achieved due to the labeling program, the malfunction of components associated with the energy management control system (EMCS) has been found to be the cause for inefficient energy operation of some building energy systems. As identified by EPA, the building control malfunctions create negative impacts on energy efficiency, indoor environmental quality including thermal comfort and air quality.