Ancillary services to the grid from commercial buildings through demand scheduling and control

How can a building Heating, Ventilation, Air Conditioning (HVAC) system vary its real time power consumption to provide ancillary services to the power grid without sacrificing occupant comfort? Prior work showed how this can be done if the reference power variation is of high frequency (seconds to a few minutes) so that the climate control system filters out the disturbance. This paper addresses the question of how to do that when the reference power variation is of lower frequency, e.g., periods of a few minutes to an hour. We propose a receding horizon approach to schedule the baseline cooling and heating power of a building based on weather forecasts. A lower level controller is then used to track the scheduled baseline plus ancillary service reference signal. Periodic updates to the scheduler based on measurements ensure quality of service in spite of forecasting errors. The algorithm is tested in simulation. Results show that ancillary service in the frequency range of f ∈ [1/(1 hour), 1/(10 minutes)] can be extracted from commercial building HVAC systems while still maintaining a comfortable indoor climate.