ASHRAE Journal - September 2011 - 52

Photo by David Wakely

High mass/multi-function construction. Innovation Several key innovative features have been mentioned, including the use of a fairly conventional packaged direct expansion (DX) VAV air handler with a displacement system. This innovation allows the project to achieve high levels of efficiency through innovative air delivery that extends economizer hours and lowers pressure drop. The evaporatively cooled condenser provides additional cooling savings. Thermal mass has also been explained, and the exploration into alternative software choices, with a validation of the modeling results, is forthcoming. A solar hot water system preheats domestic hot water.

Interior view showing custom displacement diffuser (bottom left). Operations and Maintenance The evaporative condenser unit used a chemical free water treatment system that requires very low maintenance, and also reduces blow down of water. The building maintenance system installed enabled the city to monitor the system remotely through a wide area network (WAN). A separate dedicated unit is used for the community room for stand-alone, after-hours operation. Cost Effectiveness The incremental capital cost of the energy efficiency measures was approximately $306,400 and the associated annual energy savings is $18,200. The total replacement cost every 20 years of the incremental systems is approximately $34,300. The simple payback for the building systems is 17 years. Environmental Impact The air handlers have been specified with R-410A, which is not a CFC and is non-ozone depleting. Compared to the Standard 90.1-2004, Appendix G baseline building, the project is expected to save approximately 147,120 kWh/year of electricity and 1,730 therms of natural gas, avoiding 127,400 lbs CO2 equivalent emissions annually. Further Study of Thermal Mass Effects To better understand the thermal mass effects on comfort, controls and energy use, Guttmann & Blaevoet Consulting Engineers helped establish a collaborative team consisting of the Sacramento Municipal Utilities District (SMUD), the City of Sacramento, the UC Berkeley Center for the Built Environment (CBE), Lawrence Berkeley National Labs (LBNL) and Johnson Controls (JCI). The study commenced in June 2011 and will be completed in July 2013. The purpose of the study is to create a greater understanding of how building technologies can be analyzed and deployed to achieve demand response control algorithms in an existing building, which also has a substantial amount of interior thermal mass. This understanding will be found by experimenting with demand response control algorithms, monitoring the resulting energy consumption and levels of comfort achieved, and maintaining digital records of the achieved results, some of which will be available for publication to the general public.
September 2011

FLOWHOOD ELECTRONIC FLOWHOOD
DIRECT DIGITAL READOUT 25-2500 CFM

AUTOMATICALLY CORRECTS FOR AIR DENSITY & BACKPRESSURE CHOICE OF METERS - AIR FLOW ONLY, OR AIR FLOW, VELOCITY, PRESSURE & TEMPERATURE OPTIONS INCLUDE: MEMORY, AVERAGE & SUM TO 2000 READINGS, SEQUENTIAL RECALL, AUTO-READ REPAIR POLICY - TWO WEEK TURNAROUND OR LESS CUSTOM TOPS MADE TO ORDER

Shortridge Instruments, Inc.
7855 East Redfield Road • Scottsdale, Arizona 85260 (480) 991-6744 FAX (480) 443-1267

www.info.hotims.com/37990-59

ASHRAE Journal

Photo by David Wakely

ASHRAE Journal - September 2011

Table of Contents for the Digital Edition of ASHRAE Journal - September 2011