Mapping the Effect of Ambient Temperature on the Power Demand of Populations of Air Conditioners

The direct load control (DLC) of populations of air conditioners (ACs) is a cost-effective demand-side strategy to manage peak demand and provide ancillary services to the electricity grid. Much research in recent years has focused on the formulation of mathematical models for the aggregate demand of such populations as a basis for DLC analysis and design. These models, however, are sensitive to ambient temperature, which is often assumed constant, and rely on the knowledge of thermal parameters that are typically difficult to obtain. This paper develops a new mathematical model to map the effect of ambient temperature to the aggregate demand response of a heterogeneous population of ACs. The significance of this new model lies in that it can be used to estimate the thermal parameters that characterize aggregate demand using available local weather and demand data, with no need for additional metering or direct engagement of grid users. While the estimation of these parameters is of independent interest in mapping distributed building energy performance over the grid, a key additional benefit is that these parameters fit existing models for DLC design, which provides the technical basis for practical model-based DLC of populations of ACs.