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The Advanced Energy Design Guide for Grocery Stores (AEDG-Grocery) is intended to provide a simple approach for contractors, designers, and owners to achieve 50% savings in grocery stores and other like retail that has refrigeration systems. Application of the recommendations in the Guide should result in grocery stores with 50% energy savings when compared to those same stores designed to the minimum requirements of ANSI/ASHRAE/IESNA Standard 90.1-2004. Energy Standard for Buildings Except Low-Rise Residential Buildings.

This project focuses on testing and demonstrating both the hardware and Cloud versions of theSMDS under field conditions. The objectives for testing and demonstrating the hardware are to 1) characterize the performance of the SMDS technology, 2) estimate the savings-to-cost ratio for demonstration units, and 3) characterize the usability of the SMDS including ease of installation and use. The SMDS provides information to the user, but to realize savings, actions must be taken by the user. The hardware demonstrations seek to discover how effective information is in influencing actions, including which faults generate the most servicing actions by the user.

These field demonstrations are of prototype SMDS units, which have not yet completed the product development process. These early demonstration projects are critical to understanding SMDS performance in the field and to gaining a better understanding of the potential performance or user interface enhancements needed in the next generation SMDS units. Conclusions related to the larger commercial building market, such as the incidence of performance degradation and specific faults and the energy savings resulting from addressing them are beyond the scope of this study and not compatible with the current stage of SMDS development.

The demonstration was performed separately for the hardware and Cloud versions of the SMDS. Both demonstrations involved selecting buildings, installing the required hardware (although it requires less hardware, the Cloud version requires sensors and cell modems), collecting and processing data, and viewing and tabulating results. Details of the procedures are presented later in this report.

In 2011, the U.S. Department of Energy’s Building Technology Office (DOE’s BTO), with help from the Better Buildings Alliance (BBA) members, developed a specification (RTU Challenge) for high performance rooftop air-conditioning units (RTUs) with capacity ranges between 10 and 20 tons (DOE 2013). Daikin’s Rebel RTU was recognized by DOE in May 2012 as first to meet the RTU Challenge specifications. This report documents the testing of a Rebel unit and a standard reference unit in the field and compares the seasonal efficiency of the two units.

The goal of the RTU Challenge demonstration was to estimate the seasonal performance of the RTU Challenge unit and the annual savings that could be achieved by installing the challenge unit instead of an alternate standard unit. The demonstration took place at two grocery stores located in New Smyrna Beach and Port Orange, Florida. The Rebel unit was installed as a replacement of an existing unit in July 2013 at the New Smyrna Beach store. The reference unit was an existing rooftop unit in the Port Orange store that is about 6 years old. The reference unit had two compressors for staged cooling and a constant-speed supply fan. Both units had the same rated cooling capacity of 7.5 tons and served each store’s office spaces with similar footprints.

A set of sensors were used to measure the dry-bulb temperature and the relative humidity for the outdoor-air, the return-air, the mixed-air, and the supply-air. RTU total power consumption was also measured using a power transducer. These sensor measurements, together with a number of control signals were monitored at 1-minute intervals from August 2013 to September 2014.

The average daily energy efficiency ratio (EER) was computed for each unit using the monitored data. The ratio of the average EER for the two units varied between 0.9 and 2.4. The Rebel unit had a higher daily EER than the reference unit for almost all days. The EER ratio increased as the daily average outdoor-air temperature decreased, as expected. This means that RTUs with variable-speed compressors and variable-speed fans, like Rebel, had better part-load efficiencies than units using constant speed supply fans and ON/OFF controls for compressors. The average of the daily EER ratio for all days was approximately 1.38, which means that on average, the daily EER of the Rebel unit was 38% higher than that of the reference unit.

In addition to daily EER, the seasonal cooling efficiency was also calculated over the entire monitoring period. Over the 12-month period, the reference unit and the Rebel unit had seasonal EERs of 8.3 and 10.9, respectively. The Rebel unit’s seasonal EER was about 31% higher than the reference unit. This result was slightly lower than the findings from our previous simulation work, which estimated that in hot and humid climates, Rebel would consume about 40% less electricity than a RTU with a constant-speed supply fan and a single-stage mechanical cooling. Possible reasons for this difference included: 1) the load that the two units in the field served were different, while the two units in the simulation served the same load; and 2) the reference unit had higher operating efficiency than the number used in the simulation runs.

The annual energy savings from the rooftop unit replacement with Rebel was about 16,000 kWh, which translated to roughly 3.8 years in simple payback.

It was a challenge to find two units running in two different spaces that had served similar cooling loads. Although two grocery stores with similar layouts were selected, the monitored data showed that they had noticeably different load profiles. Therefore, absolute energy savings between the two units could not be calculated. If the absolute savings measurement were desirable, then the existing RTU will have to be monitored for 1 year, followed by a year of monitoring of the Rebel unit after it replaces the existing RTU.

Other issues related to the installation of the Rebel unit included:
-The Rebel unit came with a different base footprint from the existing Lennox unit. Although a curb adapter was provided, it left the unit suspended over the front side of the base, and was ultimately supported by blocks.

-Although the new Rebel unit was considerably heavier than the unit it replaced, no roof reinforcement was needed.

The store that had the Rebel unit reported no comfort issues either positive or negative. The Rebel unit had a Micro Tech III controller, which was not compatible with the existing Emerson E2 BX controller, or the Emerson building automation system (BAS). Emerson had an application for the Micro Tech II controller but not for Micro Tech III. Therefore, the store had to install an output board with a set of dry contacts to control the RTU indoor fan. They also had to add an interface to monitor the indoor fan “On/Off” status and the supply/return temperatures, but they could not control any cooling/heating/speed control functions. All operations were controlled directly by the Micro Tech III controller in the unit with input from the zone temperature sensor.

The start-up and commissioning of the Rebel was challenging because the local Daikin distributor who installed the unit had very little experience in installing these new units. In addition, the controller had many features with a large instruction/operation manual, which made it difficult to properly configure. It took the distributor a couple of trips to configure the unit correctly, but after it was configured, the unit, as well as its metering and monitoring system worked as expected. Over the last 12-month period, maintenance requirements for this unit were similar to the other units.

One of the nation’s largest schools serving over 60,000 students, the University of Minnesota (U of M) is upgrading the lighting at all 18 parking ramps and garages on its Minneapolis campus. In the Northrop Auditorium Garage, a small 24,000 square foot facility with 75 parking spots, U of M replaced low-wattage high-pressure sodium fixtures with high efficiency, lower- wattage LED fixtures with lighting controls. This Lighting Energy Efficiency in Parking (LEEP) Campaign Award winning project achieved 90% energy savings by upgrading to LEDs with lighting controls.

NorthBay VacaValley Hospital completed lighting retrofits to their 150,000 square foot parking lot and its 225 parking spaces. They did so with help from The California Lighting Technology Center (CLTC) at the University of California, Davis. The project has achieved 65% savings and received a 2014 Lighting Energy Efficiency in Parking (LEEP) Campaign’s award for best use of lighting controls. In addition, the retrofits improved lighting maintenance operations and end-user satisfaction.

The lighting retrofit included replacing roughly 50 induction luminaires with new LED fixtures with embedded lighting controls.
The new LED fixtures were coupled with various kinds of lighting control systems, including a radio frequency (RF) connectivity control system that was installed in dedicated zones with passive- infrared (PIR) and long-range microwave sensors to achieve energy savings. An “ultra-smart” lighting control network was also put in place, giving facility managers the ability to adjust lighting schedules, light levels and time-out settings, monitor the system’s energy use, and receive automated alerts when luminaires require maintenance.

When it comes to achieving significant sustainability gains, an international retail giant has unique opportunities to cut energy use. With a total of 4,500 sites, Walmart’s commitment to efficiency in parking lighting in new construction and retrofits is paying off in major savings.

As a result of its lighting upgrades Walmart received individual Lighting Energy Efficiency in Parking (LEEP) Campaign awards for a superstore, a neighborhood market and a Sam’s Club. Across 100 stores including both new and retrofitted sites, over 40 million square feet in surfaces for parking and over 100,000 parking spaces, Walmart is saving over 15 million kWh each year as a result of lighting upgrades.

With 7 hospitals and 22 physician locations serving more than 9 Wisconsin counties, ThedaCare has ample room to implement and reap the benefits of building efficiency measures. At the Appleton Medical Center, ThedaCare’s Lighting Energy Efficiency in Parking (LEEP) Campaign Award winning project involved replacing inefficient medium-wattage HID lighting fixtures at a 126,000 square foot parking structure with high efficiency low-wattage LED fixtures. The resulting energy savings exceed 80 percent of the previous usage. A 100-year old company and the third largest health care employer in Wisconsin, ThedaCare has now implemented LED exterior lighting throughout Appleton Medical Center.

Kimco Realty Corporation’s large facility portfolio could be considered quite challenging to some organizations trying to reduce energy savings, but Kimco was able to provide upgrades to 160 sites across 25 states over 2 years. The 50-year old real estate investment trust based in New Hyde Park, New York was a 2014 Lighting Energy Efficiency in Parking (LEEP) Campaign winner for Largest Absolute Number of Facility Upgrades. Kimco has reduced their lighting energy usage primarily through the use of lighting controls for their parking lots representing approximately 51
million square feet of parking area. Kimco, which owns and operates over 800 shopping centers in North and South America, can add their LEEP accomplishments to their 2013 National Association of Real Estate Investment Trusts (NAREIT) award for leadership in sustainability and energy efficiency.

The second largest gaming company in the world by revenue, MGM Resorts International (MGM) has recently installed energy efficient parking area lighting and controls at 65% of its U.S. facilities. With 20 U.S. facilities in NV, MI, and MS, MGM lighting projects have covered more than 8 million square feet of parking area. By replacing more than 4,400 existing metal halide and high-pressure sodium light fixtures in the parking facilities with a mixture of LED and induction fixtures, MGM saved 4.5 million kWh per year across their portfolio.

Most impressively, at the MGM Grand Detroit Casino–a 401-room hotel and gaming facility— the company achieved 4 million kWh of annual energy savings by replacing medium-wattage metal halide fixtures in a 2.6 million square foot parking structure with high efficiency, low- wattage LED fixtures.

The JBG Companies (JBG), an investor, owner, developer, and manager of real estate in the Washington, D.C. Metropolitan Area, achieved almost 50% energy savings compared to energy code by using a combination of high efficiency LEDs coupled with lighting controls for the parking structure at the National Cancer Institute (NCI) Shady Grove in Maryland. The NCI
parking structure was recognized by the Lighting Energy Efficiency in Parking (LEEP) Campaign for the Highest Percentage Energy Savings in a Single Parking Structure (New Construction)
and Highest Absolute Annual Energy Savings in a Single Parking Structure (New Construction). In addition to its 2014 LEEP Campaign Award, the buildings have also been recognized in 2011, 2013, and 2014 by both local Maryland organizations and national organizations.