IBEW 332 owns and occupies a 29,000 sqft single story office building at 2125 Canoas Garden Ave. in San Jose, California. The building has just been awarded the ENERGY STAR.
The building was constructed in 2001 and its 50KW solar on-site generation system is one of the first commercial solar power installations in San Jose. The entire building, including the two tenant occupied spaces is conditioned space. Occupancy during the day is somewhat less than average, but the building is extensively used on nights and weekends for a variety of special events.
The building has been maintained to adequate standards since its construction, so there were no major problems with any of the mechanical systems, with the exception of the solar system, which was only generating about 50% it's rated output. A thorough cleaning along with a detailed investigation and associated repairs, mostly dealing with minor wiring problems and a faulty combiner box improved the solar production dramatically. Since the HVAC system had never been fully commissioned when new, there were a number of issues that were resolved by a complete system calibration and air balance, including minor repairs to a number of the VAV boxes. Overall occupant comfort and satisfaction is up significantly as a result. In addition, a custom economizer was designed and installed in the central electrical equipment room which dramatically reduced compressor duty cycle time for this 24/7 conditioned space. Steps were also taken to limit BTU losses from the domestic hot water system by implementing timed scheduling of the hot water recirc loop.
The single largest energy efficiency improvement came from aggressive programming of the upgraded BMS (building management system). In order to facilitate aggressive turn down of the HVAC system for the IBEW offices, the air conditioning system was altered so that zones where weekend conditioning is required were assigned to one, smaller rooftop unit. The system schedule changes also limited the number of run hours for the re-heat boiler based on outdoor air temperature and dramatically reduced simultaneous heating and cooling.
