AG 2012 11 19 - Laserfiche WebLink

Home Browse Search

Duke +I Energy shall be used to determine start time, so that the space conditions are satisfied at the set occupancy time. Units shall shut off at the end of occupancy hours, but have the ability to come back on using a timed override algorithm. This should be used to bring units on during evening and weekend hours as required. Units should be able to cycle on during unoccupied mode, with the outdoor air dampers closed, if needed to maintain unoccupied set points. • Add VFDs to AHU1 in Building 1000: Adding variable speed drives to supply and return fans provide for improved VAV system control and allow the fans to use less energy than the inlet guide vanes currently installed. • Separate VFD control of supply and return fan on Building 2000 AHU2: An alternative would include tapering back with inlet guide vanes. (Further study required). • Re- balance all zones in Buildings 1000, 2000, and 3000: The box retrofit should also include re- balancing of the building including setting boxes to have minimum ventilation requirements as required by current ventilation standards. This will ensure proper flow to the tenant spaces, and increase the ease for which the building zones can be controlled. Further study will be necessary to determine if demand controlled ventilation is a viable option, especially in Building 3000 where CO sensors already exist. • Implement control algorithm: Look at VAV box positions and do the following: • Reset duct static pressure set point so that the units run at the lowest possible pressure to satisfy all VAV boxes • Reset supply air set point when all boxes are at minimum position to reduce sub - cooling of spaces Note that the primary strategy is static pressure reset resulting in fan energy reduction. • Economizer Control: Install new controls for economizer changeover to allow the three air handlers to utilize outdoor air for "free cooling" when the outdoor temperature and humidity levels are lower than inside the building. 5.3 ECM 3: Lighting Upgrades 5.3.1 Interior lighting - Future ECM (to be evaluated) Group Re -lamp with reduced - wattage lamps or fixtures: RCCC should consider group re -lamps of existing fixtures with reduced -watt lamps and high - performance ballasts. This should be completed in phases as existing ballasts and lamps depreciate. Since lighting is attributed to approximately 25 to 30% of the base building load, these savings can add up. We recommend the following retrofits for future consideration: • Retrofit 32W T8's to 25W or 28W T8 lamp and ballasts • Retrofit 54W T5's to 49W T5's • Down lights should be retrofit with low -watt LEDs or dimmable CFLs, especially in areas with considerable daylight. Daylight Control: A large amount of the building's floors receive a significant amount of natural light through the abundance of windows around the facility. Lights in exterior zones could be retrofitted with dimmable ballasts, and wireless low voltage ambient photocell sensors. Rev A 2012 -05 -15 Page 23 Final Draft G -2 Page 347