In this article, Life Cycle Assessment (LCA) and Life Cycle Costing (LCC) quantify the performance of variable and fixed speed centrifugal chillers using two refrigerants (HCFC 123 or HFC 134A) in commercial air-conditioning systems. Electricity demand during operation causes the highest environmental and economic burdens for all options. Detailed energy simulation shows that chillers operate most of the time in partial load, therefore energy-optimised variable-speed systems are preferable. We demonstrate the significance of understanding each phase of the life cycle to optimise overall performance. A systems approach, if broadly applied, could reduce the barriers between stakeholders along supply chains.