Replacing Inefficient Equipment - An Engineering Analysis to Justify Purchasing A More Efficient Chiller

Chiller energy consumption in commercial buildings accounts for about 40% of HVAC system energy consumption, and about 30% of the total energy use in the whole building. Being the largest energy component in the building, the chiller energy use is the greatest contributor to the cost of utilities. The Connally Building is an office building, with a total floor area of approximately 123,960 ft 2 . Field studies indicated the need to evaluate the existing chiller plant’s economic performance. Specifically how well the plant, as a whole system, met cooling loads of the building, and how this affected their use. This paper reports our findings from an engineering analysis of the Connally Building, aimed at improving the energy efficiency of a conventional chilled water plant during the commissioning activity. Utility bills (electricity and gas) and oneyear trended data for chillers’ operation were analyzed for the chiller plant evaluation of different energy conservation opportunities. The commissioning measures for the chiller plant optimization have been specifically recommended to improve chiller plant operation performance.