Exergy-based model predictive control for building HVAC systems

Exergy has been extensively used to assess the efficiency of energy systems. This metric is relevant to quality of energy and is also a measure of sustainability. In this paper, exergy model of a building is presented and exergy destruction is formulate as a function of the physical parameters of the building model and environment. The exergy model is then used to develop model predictive control (MPC) strategy based on the minimization of exergy destruction. Compared to a traditional on-off controller, the proposed exergy-based model predictive control (XMPC) achieves 22% decrease in exergy destruction and 36% reduction in energy consumption for the building. Simulation results also demonstrate the benefit of XMPC compared to energy-based MPC (EMPC). The results indicate XMPC leads to 4% less exergy destruction compared to EMPC while providing 12% more energy saving.