As the largest school district in the state of Texas, and the seventh largest in the nation, Houston ISD covers over 300 square miles, and has an enrollment that tops 200,000 students. ESA was retained to assist the school district in assessing their utility usage, equipment needs, and potential methods of reducing their second largest annual budget item, energy. For five months, teams of engineers performed site surveys on each of the 264 campuses, consisting of 1,962 buildings, and over 25 million square feet. The services provided to the school district included mechanical equipment assessment, energy efficiency evaluation, energy consumption analysis, energy consulting, and cost estimating. Based on ESA's recommendations, the potential cost to implement the recommended energy reduction strategies ranged from $18.4 million to $57 million, depending upon the scope of work. The potential annual cost savings to the district was estimated to be between $4.8 million and $13 million.