Demand response control of residential HVAC loads based on dynamic electricity prices and economic analysis

Abstract

During peak hours, electrical loads of residential HVAC systems can cause imbalance between electricity supply and demand. Demand response control has the potential to facilitate supply–demand balance. The demand side load control can help reduce electricity consumption through demand response programs. Since HVAC loads are the major contributors to peak loads, reducing HVAC load at peak hours is an objective of many demand response technologies. This article analyzes performance of the dynamic thermostat controller of HVAC systems in homes that have dynamic price of electricity. Based on a price signal, the dynamic thermostat controller sets back the thermostat temperature to save electricity consumption and costs. The consumers choose participation in the demand response program based on the real-time price of electricity and set a threshold price that the thermostat uses to set the temperature during peak power price period. The performance of dynamic thermostat controller was analyzed for two cities, Austin TX and Chicago IL, and historical market price data were used to generate hourly based real-time price. In addition to different climate zones, two different types of residential buildings were modeled. Based on detailed energy simulation, the changes in HVAC system operation were analyzed when considering electric energy saving, peak power reduction, cost saving, as well as the potential thermal discomfort. The specific results show that dynamic pricing combined with dynamic thermostat controller results in 12% annual energy cost savings for HVAC operation with the energy saving of up to 6%, but without significantly changing the thermal comfort.