Investigate Peak Demand Reduction Strategies In A Large Office Building Using Energyplus

With the rapidly increasing demands placed on utilities, reducing peak loads and minimizing energy use assume greater importance than ever before. To combat these increasing demands, utilities offer incentives to customers that can shift peak demand to non-peak times or reduce peak loads when notified by the utility that the demand on the grid is close to capacity. This study chose to investigate the control strategies used to reduce building peak demand during a fixed window within a utilities on-peak time period in response to short notification of critical peak periods. The window was chosen to be 6 A.M. in winter, and 2 RM. in summer with a duration of three hours in both winter and summer. The selected large office model was primarily developed by the U.S. National Renewable Energy Lab. Energy Plus is used as a simulation tool for this investigation. Light and heavy building constructions are used to investigate thermal mass impact. Two types of HVAC systems are examined: VAV with reheat and constant-volume dual duct system. The selected control strategies are lighting power density reduction, cooling and heating thermostat setpoints setback control, supply air temperature adjustments, and chilled water temperature reset. The work presented in this paper is a partial work of ASHRAE research project 1390-RP: Short-term Curtailment of HVAC Loads in Buildings. The objective of the project is to identify and evaluate peak demand reduction strategies in response to a short notification. The control strategies are found to be dependent on HVAC system types and locations and almost independent of building constructions. The most effective strategy with VAV with reheat system is lighting power density reduction. The chilled water temperature reset is a close second. These two control strategies are easily implemented. The most effective strategy with dual duct system is chilled water temperature reset and supply air temperature adjustment. The light density power reduction is also recommended. However, thermostat setpoint control setback is not recommended