Energy use in chemical plants, such as refineries and petrochemical facilities is complex and interrelated. Identifying where and how energy use can be improved is best pursed using a system approach that inherently takes these complexities and interactions into account. This article will demonstrate the basic principles and capabilities of pinch technology; how its energy targeting capability is used to determine the scope for reducing energy consumption and costs; and the design methods used to improve heat-recovery networks and process-utility systems for olefin plants. The intent is to illustrate the potential for energy recovery in each chemical process, how much heating/cooling is actually required for the process, and how we can design a process that achieves the energy target.