Application of Lorenz Curve and Gini Index in the Analysis of Load Fea-ture in HVAC Systems

Load feature includes how load requirements distribute among different zones and how load requirements change along the time. These characteristics influence the energy consumption and efficiency of the HVAC system significantly. Traditional method can hardly describe the load feature in a clear and straightforward way. This paper examines the load feature and its influence using Lorenz curve and Gini index. Lorenz curve can describe the load distribution among zones or times graphically, and Gini index can identify the unevenness degree in a quantitative way. Different Gini indexes, which correspond to different load features, are compared to reveal the influence of load features on the supply, distribution and adjustment process in HVAC systems. Higher Gini index reveals that the load requirements distribute un-evenly among zones and along times, which usually leads to the oversupply, the loss of distri-bution power, the entransy dissipation and a lower heating/cooling source efficiency.