Skip to content

Posts tagged ‘supermarket’

Strategies for Maximizing Refrigeration System Efficiencies

Andre Patenaude | Director – Solutions Integration,

Emerson’s Commercial and Residential Solution’s Business

For many supermarket operators, reducing energy spend in their refrigeration systems is a key sustainability objective. But as most refrigeration systems drift from their original commissioned states, they inevitably lose efficiencies over time. In a recent RSES Journal article, I explored some of the root causes of this all-too-common problem and presented proven strategies for maximizing refrigeration system efficiencies.

There is often a domino effect that contributes to declining refrigeration efficiencies: setpoints are changed, mechanical subcooling strategies become ineffective, condensing pressures increase, and overall system energy consumption rises. At the same time, maintaining consistent case temperatures can become a constant struggle — often causing the reliability of these systems to suffer.

But this inefficient, unreliable state neither has to be your status quo, nor does it necessarily mean that it is time to replace your existing refrigeration system. In fact, there are a variety of tools and techniques for taking back control of your supermarket refrigeration system.

Shore up your liquid subcooling strategy

Refrigerant (liquid) subcooling results in denser liquid — which packs more BTUs per pound and maximizes system capacity and performance — and is a strategy utilized within many supermarket refrigeration systems. But because this approach is based on design parameters that account for the hottest anticipated day of the year, it can present challenges in other weather conditions. In some regions, this can represent more than 95 percent of the time

As ambient temperatures drop, the condenser operates more efficiently, thus decreasing the subcooling load requirements. The net effect is that the plate heat exchanger — which acts as an evaporator to cool the refrigerant — is oversized for most of the year. And as the system tries to adapt to changing weather conditions, the liquid quality output can become more erratic and cause flash gas in liquid lines, which can starve the evaporator.

To manage this load variability, system designers often use electronic evaporator pressure regulators (EPRs), which must be properly set to maintain ideal liquid-out temperatures. If not, these conditions can combine to create a perpetual state of fluctuation as the system “hunts” for the liquid quality for which it was designed, resulting in a myriad of system issues with the potential to negatively impact energy efficiency and reliability.

Install electronic expansion valves

Replacing a system’s mechanical expansion valves with electronic expansion valves (EEVs) is the key to helping operators overcome these subcooling challenges and restoring system efficiencies. EEVs are typically located at the inlet of the subcooler to control and modulate the refrigerant flow of the heat exchanger much more effectively, regardless of whether it is the hottest or coldest day of the year. As temperatures and liquid quality fluctuate, EEVs allow a system to run at maximum capacity and deliver the performance advantages for which it was originally designed:

  • Higher BTUs per pound of circulating refrigerant
  • Reduced liquid line size and charge reduction
  • Improved efficiency for energy savings

Note: for optimum control of a subcooling heat exchanger equipped with an EEV, consider using a variable-capacity compressor like the Copeland™ scroll digital compressor or adding a variable-frequency drive (VFD) to a Copeland Discus™ compressor to provide a balanced load approach.

Raise system suction pressures

The higher the system suction pressures are, the lower the associated compressor power consumption will be — particularly in lower-temperature refrigeration systems. For every 1 PSI increase in suction pressure, a compressor’s energy efficiency ratio (EER) is improved by approximately 2%.

Electronic evaporator pressure regulators (EPRs) are commonly used in centralized racks to maintain evaporator temperatures within various suction groups and optimize the suction pressure to its highest possible point based on case demand. To save additional energy, technicians may “float the suction pressure” by allowing it to rise slightly when the lowest temperature case is satisfied. This can only be achieved if the EPRs are properly set.

Low-condensing operation

Another way to offset the inefficiencies of a system designed for the hottest day of the year is to implement low-condensing operation (aka “floating the head pressure”). Instead of artificially keeping head pressures near 105 °F with the use of head pressure control valves, EEVs installed at cases allow systems to float head pressures down as the temperatures drop — typically maintaining temperatures at 10–20 °F above the ambient temperature.

On average, systems can achieve 15–20% EER improvements on compressor performance for every 10 °F decrease in head pressure. EEVs are designed to modulate with fluctuations in capacity and liquid quality to digest flash gas and control superheat. Using this technique, supermarket operators can reliably float system pressures to 70 °F or lower and achieve:

  • 15–20% EER improvements on compressor performance
  • Increased compressor capacity for faster pull-down rates
  • Lower pressure, which reduces system stress
  • Higher system reliability, which lowers total cost of ownership (TCO)

Give your system an efficiency boost

Emerson provides the tools, technologies and expertise to help operators implement efficient liquid subcooling and low-condensing pressure strategies. Our EX series EEVs feature a patented ceramic gate port design that can manage a wide range of liquid quality and condensing pressures — and deliver precise refrigerant control via variable-capacity modulation from 10–100%.

The companion EXD-SH1 or SH2 superheat controller regulates evaporator superheat to optimize system performance, regardless of ambient conditions. Its integrated display allows operators to check a variety of system conditions, such as superheat, percentage of valve opening, pressure and temperature values.

Evaluating Sustainable Supermarket Refrigeration Technology

AndrePatenaude_Blog_Image Andre Patenaude | Director, Food Retail Marketing & Growth Strategy, Cold Chain

Emerson Commercial & Residential Solutions

Progressive Grocer recently interviewed me about Emerson’s and the commercial refrigeration industry’s efforts to help promote the emergence of more sustainable, refrigeration technologies. The complete article can be found here.

Evaluating Sustainable Supermarket Refrigeration Technologyd

It’s not news that supermarkets are under continuous regulatory pressure to not only lower the energy demand of their refrigeration systems, but also to make the transition to low global warming potential (GWP) and zero ozone depletion (ODP) systems. The permanent ban on R-22, long the industry standard, becomes official on January 1, 2020.

What is news is how intensely suppliers and retailers are focused on and sharing information on sustainability initiatives intended to sharply reduce the costs and impact of their refrigeration systems, both in anticipation of future regulations and to attain long-term economic and environmental sustainability.

As different manufacturers approach these issues with a variety of new technology options, the challenge becomes defining new standards for sustainable products and systems, so that the industry can converge on proven, synergistic solutions.

Taking a full system’s approach to sustainability

At Emerson, our approach to sustainability is based on a multi-faceted goal. First, sustain the environment through lower-GWP refrigerant and technology choices. Second, sustain companies financially from a total cost of ownership perspective. And third, focus on energy efficiency as a path to sustainability through forward-looking engineering and the implementation of new monitoring and control technologies, particularly Internet of Things (IoT) capabilities.

At Emerson, we take a full system approach to evaluate the sustainability of new and existing technologies in the context of multiple key selection criteria. This is part of Emerson’s “Six S’s” approach to refrigeration sustainability: simple, serviceable, secure, stable, smart and sustainable.

(To learn more about the rationale, methodology, application and impact of Emerson’s “Six S’s” philosophy, read the blog found here.)

Exploring the potential of natural refrigerants

One area of Emerson’s focus is our work to better understand and then implement emerging natural refrigerants, such as R-744 (carbon dioxide) and R-290 (propane) for different types of applications.

Recent innovations include the development of an integrated display-case architecture. This R-290 system is designed to use one or more compressors and supporting components within cases, removing exhaust heat through a shared water loop — incorporating our expertise in R-290 compressors and our experience with stand-alone condensing units. We’ve also developed a full range of CO2 system technologies, including valves and controls for both small and large applications. For cold storage applications, our modular refrigeration units utilize both CO2 and ammonia-based refrigerant configurations.

Early adopters pave the road to the future

Over the past decade, there have been many retailers committed to testing sustainable refrigeration technologies and low-GWP refrigerants in their stores. For example, the article quoted Wayne Posa of Ahold Delhaize USA, who discussed the company’s transition from R-22, stating: “Food Lion has been committed to zero-ODP and low-GWP refrigerants for several years.”

Different manufacturers are taking different approaches to studying and applying refrigerants and technologies to reach that goal, from the use of hydrofluoroolefin (HFO) refrigerants (such as R-448A and R-450) in distributed refrigeration systems to proven CO2-based system architectures.

In the area of refrigerants — let alone technologies in development for increased energy efficiency and remote monitoring and control — the refrigeration industry continues its search for a new standard. As Brian Beitler of Coolsys, a consulting and contract engineering firm explains, “Between transcritical, ejector systems, NH3 over CO2, cascade, propane, multidistributed and hybrid gas coolers, the jury is still out.”

As we move closer to the most sustainable standard for refrigerants, Emerson continues its work on total refrigeration system sustainability — in refrigerants, energy efficiency, and control — as guided by our “Six S’s” philosophy. This work is our road map to the future.

 

[New E360 Webinar] Best Practices in Enterprise and Facility Optimization

ronchapek_2 Ron Chapek | Director of Product Management

Emerson Commercial & Residential Solutions

In today’s competitive food retail and foodservice markets, empowering your service teams to provide fast, effective issue resolution can be a true differentiator. In our next E360 Webinar, which will take place on Tuesday, Oct. 29 at 2 p.m. EDT/11 a.m. PDT, we will explain how new enterprise management and collaboration tools can help operators optimize their service teams and implement efficient processes across the enterprise.

Supermarket, convenience store and restaurant operators are faced with a perfect storm of facility management and servicing challenges. As the pool of qualified technicians continues to shrink, those entering the service profession have limited systems knowledge and must quickly learn to navigate an increasingly complex landscape of new technologies and architectures. Simply put, operators need new tools to help their service teams:

  • Process and prioritize alarms per specific geographic regions, areas of responsibility and importance to business success (HVAC, refrigeration, ice machines, beer coolers, etc.)
  • Access the information needed to resolve issues quickly and fix equipment failures on the first attempt

In our next E360 Webinar, I’ll be joined by Pranay Shah, senior technical product owner at Emerson, to discuss how new enterprise software and collaborative community platforms can be combined to prioritize, triage and accelerate issue resolution for both internal service teams and supporting contractor networks. As we explore how to leverage these powerful and intuitive tools to streamline facility management and servicing processes, attendees will learn:

  • How enterprise management software can be tailored to end user roles and responsibilities
  • How these tools can be mapped to specific processes per unique business objectives
  • How alerts are filtered and prioritized to address next most important tasks
  • How service networks and communities enable team collaboration, live chat, video and technical knowledge base access

So if you’re ready to learn how to put these tools to work in your organization — and better optimize the service teams and processes with which you manage them — then register now for this informative webinar and make plans to join us on Tuesday, Oct. 29 at 2 p.m. EDT/11 a.m. PDT.

[New E360 Webinar] Why Retrofit Your Aging Supermarket Refrigeration Architecture?

AndrePatenaude_Blog_Image Andre Patenaude | Director, Food Retail Marketing & Growth Strategy, Cold Chain

Emerson Commercial & Residential Solutions

Many supermarket operators face a common dilemma regarding their refrigeration systems: they know they need to make changes or upgrade their legacy systems, but they’re not sure what their retrofit options are — or even where to begin. In our next E360 Webinar, I’ll offer guidance on how supermarket owners/operators can embark on this critical journey.

Join me on Tuesday, Aug. 13 at 2 p.m. EDT/11 a.m. PDT for this informative webinar.

[New E360 Webinar] Why Retrofit Your Aging Supermarket Refrigeration Architecture?

There’s no question that reliable refrigeration is the backbone of any supermarket operation; it accounts for more than 50 percent of the electrical consumption for an average supermarket. That’s why keeping your refrigeration system running at optimal efficiency is essential to maximizing profits and ensuring operational success.

But if you’re like many owners/operators, you’ve been relying on the same centralized refrigeration architecture for decades. During that time, these systems have typically experienced declining performance levels and energy efficiencies — all due to progressive deviations from their original commissioned states. And while these systems are perfect candidates for an upgrade or a retrofit, even newer systems can offer opportunities for improvements, especially within the context of today’s rapidly evolving industry and market dynamics.

Compared to just 10 years ago, the drivers behind refrigeration decisions have changed dramatically, and the days of a one-system-fits-all mentality are quickly becoming a thing of the past. Environmental concerns, energy costs, shifting regulations, shrinking store formats, consumer demands and omnichannel delivery have all irrevocably reshaped the supermarket landscape.

As a result, more supermarket owners/operators are reevaluating their existing (and often aging) systems while looking for any retrofit opportunities that are available to them. Our next E360 Webinar is designed with them in mind. To help you better understand the many factors to consider when evaluating a supermarket refrigeration retrofit, I’ll be discussing the following topics:

  • Industry and market trends driving the need for refrigeration system retrofits
  • How to identify deficiencies and baseline performances in centralized architectures
  • A look at the potential architectures of the future
  • Recommended technologies for retrofits and recommissioning
  • Energy-efficiency strategies for refrigeration, HVAC and the complete building envelope

As always, we will take time after the presentation to answer any of your questions. So, be sure to register now and add this event to your August calendar.

10 Takeaways From 10 Years of GreenChill Data

JohnWallace_Blog_Image John Wallace | Director of Innovation, Retail Solutions

Emerson Commercial & Residential Solutions

The Environmental Protection Agency’s (EPA’s) GreenChill Advanced Refrigeration Partnership recently completed a 10-year study examining supermarket data trends. In our latest E360 Webinar, Tom Land, manager of the program, presented these findings from GreenChill’s unique perceptive. View the webinar in its entirety or read the summary below.

Latest E360 Webinar on Demand

For more than a decade, the GreenChill program has worked with supermarket retailers across the country to promote the use of “greener” refrigeration systems in their stores. While our industry is in the early phases of transitioning to more sustainable refrigeration, GreenChill partner companies are at the forefront of this movement. The number of retailers participating has increased significantly since the program’s inception, and the data Tom discussed at the webinar provides a road map for other companies as they formalize their own sustainability initiatives.

Let’s look at 10 takeaways from the recent webinar.

  1. GreenChill partnership on the rise — in 2007, just more than 4,000 stores were GreenChill partners; today, that number exceeds 11,000 stores.

 

  1. Partner refrigerant emissions remain low — among the growing number of participating GreenChill partner stores, emissions have been held to a minimum. This is in large part due to the program’s emphasis on reducing refrigerant leaks and system charges.

 

  1. Refrigerant charges are declining — the average amount of refrigerants used in participating stores has declined steadily since 2007, even as the number of stores increases.

 

  1. Pounds per store leaks are dropping — in 2007, partner stores emitted more than 390 pounds per store every year; today, 290 pounds is average.

 

  1. Leak rates well below industry averages — on average, GreenChill partners have a leak rate of 13.9 percent, well below the industry average of 25 percent. Twelve of the partners have achieved a leak rate below 10 percent.

 

  1. One-fifth still use R-22 — although R-22 use is on the decline overall, 20 percent of commercial refrigeration systems continue to use it.

 

  1. Low-GWP refrigerants on the uptake — R-407A accounts for 20 percent of partner-installed refrigerants; installations with refrigerants less than 1,420 GWP now account for nearly 3 percent of all partner-installed refrigerants, with R-448A accounting for much of this growth.

 

  1. CO2 installations increase — installations of CO2 secondary loop, cascade and transcritical booster systems among partners continue to rise, with more than 12 partners exceeding a combined total of 160,000 pounds of installed R-744.

 

  1. Growth of GreenChill certifications — in 2009, fewer than 25 stores achieved GreenChill Gold and Silver certifications; today more than 360 stores have achieved Platinum, Gold and Silver certifications and re-certifications.

 

  1. California leads certification — among those states with GreenChill-certified stores, California leads the country with 151 stores. The next closest state is Florida with 45 stores.

Over the past decade, Emerson has worked with a variety of GreenChill partners to meet their sustainability objectives, utilizing leading low-GWP refrigerant alternatives and energy-efficiency strategies. If you’re interested in transitioning to a greener refrigeration system, we’re here to help you develop a strategy that meets your long-term goals.

%d bloggers like this: