Control of Thermal Systems for Power Frequency Regulation

Real-time power supply and demand balances are critical to ensure stable power frequency and quality power services. However, the growing integration of renewable energy increasingly challenges the power infrastructure due to their uncertain and intermittent nature. Building thermal equipment consumes more than 35% of the electricity in the US, and can be proactively controlled to providing frequency regulation to the electric grid. offering significant regulation reserve for the power grid.

We have developed frequency regulation control strategies for a range of building thermal equipment and evaluated their performances with extensive laboratory tests. Major findings are

  • Building thermal loads can provide high-quality frequency regulation services with PJM performance scores up to 0.98;
  • Charging/discharging of thermal storage involves no round-trip efficiency losses;
  • Frequency regulation control has negligible indoor comfort impact;
  • Provision of frequency regulation can provide significant economic benefits to buildings.


  • Cai, J., Optimal Building Thermal Load Scheduling for Simultaneous Participation in Energy and Frequency Regulation Markets, Energies, 2021, link.
  • Cai, J., Braun, J.E., A Regulation Capacity Reset Strategy for HVAC Frequency Regulation Control, Energy and Buildings, 2019, preprint. DOI: 10.1016/j.enbuild.2018.12.018.
  • Cai, J., Braun, J.E., Laboratory-Based Assessment of HVAC Equipment for Power Grid Frequency Regulation: Methods, Regulation Performance, Economics, Indoor Comfort and Energy Efficiency, Energy and Buildings, 2019, preprint. DOI: 10.1016/j.enbuild.2018.12.022.