Savings potential with setpoint deviation of duct pressure

This section focuses on using the 'setpoint deviation' analysis for the air handling unit (AHU). In terms of the savings potential due to deviations from the pressure setpoint, the pins 'Return air duct pressure' and 'Supply duct pressure', as well as the corresponding setpoints 'Return air duct pressure setpoint' and 'Supply duct pressure setpoint', are relevant.

Functionality

The 'setpoint deviation' analysis provides in general a comparison between the measured value and it's corresponding setpoint. In addition, the analysis provides an estimate of the potential savings if the 'exhaust air duct pressure' and 'supply air duct pressure' pins are analyzed and the actual pressure exceeds the setpoint. If the pressure exceeds the setpoint, the fan provides more duct pressure than necessary leading to an increased electrical energy consumption. The savings potential lies in reducing the pressure to match the setpoint. This scenario is illustrated in the following example.

Added value

• Identification of deviations between the duct pressure and the duct pressure setpoint
• Calculation of the savings potential by reducing the duct pressure to the setpoint
• Extrapolation of the savings potential to a calendar year

Prerequisites

1. Mapping
   In order to calculate the pressure deviation between the measured value and the setpoint, the duct pressure, the duct pressure setpoint and, optionally, an operating message must be mapped for the AHU. This is usually already done when setting up the components, provided that the necessary datapoints are available.
2. Information on the component's power
   In order to calculate the savings potential, information on the power or volume flow of the supply and/or extract air fan must be available. At least one of the following must be defined:
   • Nominal power - fan (attribute)
   • Nominal volume flow - fan (attribute)
   • Volume flow - fan (pin)
3. Adjustment of the attributes (optional)
   Adjusting the attributes makes the analysis result and the calculated savings potential more accurate. Typically, at least the following attributes should be checked:
   • Energy prices: electricity, heat, cold
   • Pressure setpoint deviation tolerance

Results

The following key figures are useful for interpreting the results of the analysis: