|
|
Supermarkets
| Supermarkets
present a unique space conditioning challenge because of the interaction
between the HVAC system and the refrigerated display cases. The display
cases provide significant sensible cooling and increase the latent load
fraction on the HVAC system. As a result, advanced dehumidification technologies
are often used to meet the latent loads as well as to lower space humidity
levels and decrease refrigeration system energy use. We have compared space
conditioning technologies through both simulation and field monitoring.
We are also developing and testing new control techniques to defrost display
cases. |
Selected Projects:
Developing the Supermarket Simulation Tool (SST)-
|
Electric Power Research Institute
|
|
Developed an hour-by-hour
building simulation program that fully models all aspects of a supermarket
including the HVAC, refrigeration and building envelope systems.
This easy-to-use Windows application allows a user to quick construct a
model of a supermarket using a library of predefined components.
Responsible for developing and programming the calculations “engine”.
Oversaw efforts to develop a Windows graphical user interface and prepared
the user documentation and on-line help. Have conducted
hands on training sessions, developed case study examples, expanded the
component libraries, and prepared promotional materials. Currently
Version 3.0 is available.
|
Supermarket Energy Efficiency Upgrades -
|
Focus on Energy
|
|
Performed audits of supermarkets to identify energy efficiency upgrades.
Analyzed upgrade impacts including hourly simulation to capture refrigeration /
space conditioning interaction. Presented recommendations to owners and their
contractors. Followed up on projects with monitoring to verify impacts.
|
Evaluating Low and
No Cost HVAC Improvements at Lunds -
|
Electric
Power Research Institute |
|
We monitored a supermarket
to evaluate the impact of low and no-cost methods to improve dehumidification
performance. We also evaluated the impact of various defrost control techniques
on display case and refrigeration system energy use. We used the DDC controls
installed at the store to monitor supermarket operation and implement the
control inprovements. |
Field Testing a Heat Pipe
Assisted Air Conditioner at Kroger -
|
Electric
Power Research Institute |
|
We field monitored the performance
of a heat pipe assisted air conditioner in at a Kroger supermarket in Indiana.
We used the DDC control system installed at the store to monitor system
performance as well as to implement several control improvments. The monitored
data were used determine the impact of heat pipes on the peak demand and
energy use of the refrigeration system, display cases, and overall store. |
Demonstration of an Integrated
Water Loop System at a Wal*Mart Super Store -
|
Electric
Power Research Institute |
|
We are collecting data on
more than 350 mointored points in a Wal*Mart Super Store in Oklahoma. We
are using the monitored data to evaluate several aspects of system performance,
including: the integrated HVAC and refrigeration water loop system, the
daylighting system, the dual path dehumidification units, and the CO2-controlled
ventilation system. |
Developement and Testing
of a "Demand" Defrost Controller -
|
Electric
Power Research Institute |
|
We are currenlty working with
a supermarket controls manufacturer to develop a "demand" defrost controler
(patent-pending). The innovative controller does not use sensors but takes
advantage of microprocessor technology to determine when the next defrost
should occur. We are working with the manufacturer to develop and evaluate
controller performance. |
Evaluation of HVAC and
Refrigeration Systems at Super-K Stores -
|
Electric
Power Research Institute |
|
We reviewed the performance
of the HVAC and refrigeration systems at several K-Mart Super-K stores
across the nation. Our goal was to determine the causes of unexpected display
case performance and recommended actions to optimize store operation. |
Evaluation of the Impact
of ASHRAE 62-1989 on Florida Supermarkets -
|
Florida
Solar Energy Center |
|
Florida
Power & Light |
|
We evaluated the impact of
the increased fresh air requirements of ASHRAE 62-1989 on supermarkets
using the building simulation model TRNSYS. The study considered both electric
and gas-fired space conditioning technologies and determined which systems
were most effective at meeting the increased latent loads. |
Field Test and Evaluation
of a Desiccant System at MET Foods Supermarket -
|
Brooklyn Union |
|
We field monitored a gas-fired
desiccant system installed on a MET Foods store in New York City. The monitored
performance data were compared to laboratory test results and were used
to develop detailed simulation models of the store. |
See our section on desiccants
and dehumidification for more information on other related projects.
|
