A technique for minimizing energy usage in a process. It is based on calculating the minimum energy consumption by optimizing the heat recovery, energy supply, and process operating conditions. It uses process data represented as energy flows, or streams, as a function of heat load against temperature. These data are combined for all the hot and cold streams in the process to give two composite curves—the hot streams releasing heat and the cold streams requiring heat. The point of closest approach between the hot and cold composite curves is called the pinch point and corresponds to the point where the design is most constrained. Using this point, the energy targets can be achieved using heat exchange to recover heat between the hot and cold streams in two separate systems, with one for temperatures above the pinch temperature and one for temperatures below pinch temperatures. First developed by chemical engineer Bodo Linnhoff in 1977 at the University of Leeds, it is also known as process integration, heat integration, and pinch technology.