In the realm of energy efficiency and grid services, a team of researchers from the University of California, Berkeley, and Tsinghua University in China have developed a novel approach to harness the flexibility of building HVAC systems. Led by Qi Zhu and Xiaohong Guan, the team has created a unified virtual battery (VB) modeling framework that could potentially revolutionize how buildings interact with the electrical grid.
The researchers have tackled a significant challenge in the energy sector: characterizing the operational flexibility of heating, ventilation, and air-conditioning (HVAC) systems. These systems are known to dominate a building’s energy consumption, yet their flexibility can be leveraged to provide valuable services to the grid, such as demand response (DR). However, the complex thermal dynamics of buildings, system operating limits, and human comfort constraints have made this a difficult task.
To address this, the team first identified a physically meaningful state representation to depict building thermal conditions within comfort constraints. They then established a VB model to characterize the operating flexibility of single-zone HVAC systems. Extending this framework to multi-zone HVAC systems, they developed zone-level VB models to capture the building’s zonal operating flexibility. Furthermore, they created a systematic method to aggregate these VB models into a low-order, low-complexity aggregated VB model, significantly reducing model and computational complexity.
The researchers demonstrated the effectiveness of their VB model through demand response applications. They found that the VB model could accurately capture the operating flexibility of building HVAC systems, enabling effective participation in demand response programs. Moreover, the DR strategies derived from the VB model could be efficiently decomposed into zone-level control inputs, ensuring human thermal comfort while achieving near-optimal operation cost.
This research, published in the journal Applied Energy, offers a promising approach for the energy sector to better utilize the flexibility of building HVAC systems. By treating buildings as virtual batteries, the grid can more effectively manage demand, potentially leading to increased efficiency, reduced costs, and improved integration of renewable energy sources. The practical applications of this research could significantly impact the energy industry, paving the way for smarter, more responsive buildings that actively participate in the electrical grid.
This article is based on research available at arXiv.