15.4 MEASURING ENERGY UTILIZATION IN POWERPRODUCING EQUIPMENT (EFFICIENCY)
In order to decide whether or not equipment is utilizing energy efficiently, there must be standards for measuring its performance. Some of these will be discussed here. Figure 15.6 shows a schematic arrangement of a power-producing device such as a turbine or engine which receives heat and converts some of the heat into power.
Heat (Q1) flow from the heat source (usually a fuel) at a high temperature to the engine which converts some of this heat to the power (P) which it produces. The remainder of the heat (Q2) is rejected to a heat sink at a lower temperature. This is usually water or the atmosphere. The values of Q1, Q2, and P are related to each other, according to the Energy Equation, as