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2016 Challenges and Trends Discussed at Recent Atlanta E360 Forum

On February 18, Emerson Climate Technologies took its E360 Forum to Atlanta. At a time when our industry is facing more questions than there are answers, 130 attendees benefitted from this educational event packed with relevant and engaging discussions, from timely keynote speakers to panel discussions and interactive breakout sessions alike. What follows is a brief summary of some of the day’s important takeaways.

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EPA Keynote: National and Global Regulatory Update — Drusilla Hufford, director of the Stratospheric Protection Division at the Environmental Protection Agency, recapped the EPA’s recent actions to reduce HFC refrigerant emissions under the authority of the Clean Air Act (CAA). She then discussed the evolution of the agency’s refrigerant management program, specifically, the proposed amendment to extend the scope of Section 608 of the CAA from its current focus on ozone-depleting substances to include HFCs with high global warming potential. Finally, she talked about the potential long-term environmental impacts of a recent agreement by the Montreal Protocol parties.

Panel Discussion: Addressing the Qualified Technician Shortage — Moderated by Kyle Gargaro, editor-in-chief of ACHR News, this lively panel discussion featured six additional industry practitioners and experts. With more than 60,000 unfilled positions in the United States’ HVACR industry, finding and hiring qualified refrigeration and HVAC technicians is becoming increasingly challenging. Audience members engaged panelists about ways to generate interest for a new generation of technicians through viable career opportunities and an increasing focus on emerging technology.

Foodservice Keynote: Tracking Fresh From Farm to Fork — Mark Dunson, president of retail solutions, addressed the consumer demand for fresh, sustainable products. He explained the high stakes of maintaining “fresh” market positions in monetary terms via the high costs of global food waste, annual global energy spend and facility maintenance expenses. As large retailers prepare to comply with the FDA’s Food Safety Modernization Act by the end of 2016, Dunson discussed how the importance of monitoring and maintaining critical data points throughout the food cold chain will lead to holistic data collection, storage and analytics solutions.

Breakout Sessions: Foodservice and Food Retail Tracks — The bulk of the event’s afternoon agenda was comprised of interactive breakout sessions, divided into foodservice and food retail educational tracks. For more detailed information about what information was covered within these sessions, please click here (click on the “Session Descriptions” tab).

To view or download the E360 Forum presentations, please visit the resources section of our website. We are planning to host two more events in the northeast and southwest parts of the U.S. later this year, so please check back for more details and make plans to attend. We look forward to your participation.

CO2 as a Refrigerant – Introduction to Retail Transcritical Systems

This is post number nine of a series.

Introduction to Retail Transcritical Systems

The diagram in Figure 1 is a simple single-stage transcritical system. The refrigerant discharged from the compressor flows into the gas cooler where heat is removed. If ambient is low the gas cooler will condense the vapor, however if ambient is high the refrigerant will not condense in this part of the system because it is operating above the critical point.

The high pressure refrigerant vapor passes through the expansion device and condenses when its pressure drops below the critical point. The liquid in the bottom of the Flash tank (receiver) feeds the MT and LT cases. Electronic valves control superheat at the outlet of all cases and vapor is drawn back to the compressors.

Figure 1

Figure 1: Simple transcritical system for medium temperature

In this simple system:

  • The temperature of the refrigerant at the gas cooler exit depends on the size of the cooler
  • The pressure of the refrigerant in the gas cooler depends on the quantity of refrigerant in the system and the ambient temperature

The capacity and efficiency of this type of system vary significantly with ambient temperature and the quantity of refrigerant in the system.

Three example systems are shown on the pressure enthalpy chart in Figure 2. Each have identical evaporating conditions.

Figure 2

Figure 2: Pressure enthalpy chart showing transcritical operation

In a subcritical system the refrigerant would de-superheat and then condense, rejecting heat at a constant temperature. In transcritical operation the R744 does not condense; it rejects heat as a supercritical fluid, cooling during this process. (Even with a wide temperature-glide HFC such as R407A, the temperature change through the condenser is small compared to that of a gas cooler in a transcritical system.)

In each example above, the R744 exits the gas cooler at a temperature of 104 °F (40 °C). This exit temperature is a function of the size of the gas cooler and the ambient temperature, in the same way as condensing temperature is a function of the size of the condenser and the ambient temperature.

The cooling capacity of each system varies significantly. When operating in supercritical mode the cooling capacity increases (at constant temperature) with an increase in pressure. This is the opposite of what happens in a subcritical operation, where cooling capacity is increases at lower discharge pressures.

The compressor power input of each system also varies. The lower the pressure the lower the power input, as in subcritical systems.

Variation in power input is not proportional to the variation in cooling capacity. For example, increasing the head pressure from condition 1 to condition 2 provides a significant increase in cooling capacity with a very low increase in compressor power input. Increasing the pressure from condition 2 to condition 3 increases cooling capacity less than the increase in compressor power input.

Unlike subcritical systems, the maximum coefficient of performance (COP) while in supercritical operation does not occur at minimum condensing pressure. Optimum COP depends on evaporating conditions and gas cooler exit temperature, but is typically 90–100 bar (1310–1450 psi). In general the pressure for optimum capacity is greater than that for optimum COP.

In a retail transcritical system, gas cooler pressure is controlled to provide optimum capacity or optimum efficiency while maintaining the pressure below the maximum allowed at all times. Figure 3 shows how this pressure is controlled in a typical retail system with single-stage compression.

Figure 3

Figure 3: Gas Cooler High pressure control

Two additional valves in this system control the gas cooler and intermediate pressures:

  • The gas cooler pressure valve 1 (also called the high-pressure regulating valve) controls the pressure in the gas cooler. It is a pressure-reducing valve controlled from the R744 pressure in the gas cooler and its exit temperature.
  • The receiver pressure valve 2 (also called the medium-pressure regulating valve or the flash gas valve) controls the pressure of the refrigerant in the receiver and associated liquid distribution pipe work. It is controlled from the pressure in the receiver. This receiver is also called a flash tank.

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Gas cooler pressure is usually selected for optimum COP unless greater capacity is needed, in which case a higher pressure would be selected.
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Subcritical Operation

The ambient temperature profile determines the proportion of time a system runs in transcritical mode. For many regions a proportion of the operation will be subcritical, typically when the ambient temperature is below 68 °F to 77 °F (20 °C to 25 °C). In this case the gas cooler pressure valve usually controls the refrigerant in the condenser such that it exits the condenser with a specified degree of sub cooling.

In the next article of this series we’ll take a closer look at retail booster systems.

Andre Patenaude
Director – CO2 Business Development, Emerson Climate Technologies

Visit our website for additional information on CO2 Solutions from Emerson. 
Excerpt from original document; Commercial CO2 Refrigeration Systems, Guide for Subcritical and Transcritical CO2 Applications.


To read all posts in our series on CO2 as a Refrigerant, click on the links below:

  1. Series Introduction
  2. Criteria for Choosing Refrigerants
  3. Properties of R744
  4. Introduction to Trancritical Operation
  5. Five Potential Hazards of R744
  6. Comparison of R744 with Other Refrigerants
  7. R744 Advantages / Disadvantages
  8. Introduction to R744 Systems
  9. Introduction to Retail Transcritical Systems
  10. Retail Booster Systems
  11. Introduction to Retail Cascade Systems
  12. Introduction to Secondary Systems
  13. Selecting the Best System

 

Three Industry Trends for Leading Convenience Stores to Consider

I recently discussed three trends convenience stores need to be aware of in order to stay competitive in this Convenience Store Decisions article. Here are some of the highlights:

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The convenience store space is continuing to evolve to keep up with industry trends and consumer demands. We see the following three trends as important for leading convenience store operators to consider in 2016 and beyond:

  1.  Convergence through convenience and differentiation

Food retail concepts are converging. Shoppers are no longer surprised to see convenience stores that look more like restaurants or smaller format grocery stores that specialize in on-the-go offerings. Flexible infrastructures are needed as retailers adapt to changing store concepts, and there is a greater need for improved equipment operation and maintenance.

  1. Increasing importance on freshness and food quality

While the idea of convenience stores offering fresh, prepared foods is not new, the trend has accelerated over the past few years, and we anticipate it will continue to grow. This leads to increasing importance on authenticating freshness and food quality. Competitive retailers will begin to use intelligent facility systems data to substantiate how their foods remain fresh from “farm to fork.”

  1. Effect of changing regulations on operations

There are three key regulations that will impact foodservice retailers in the coming years. The Food Safety Modernization Act (FSMA) changes will result in an increasing importance on collecting and utilizing data related to the safety and integrity of fresh foods. EPA and DOE regulation changes will result in retailers needing to increase their focus on refrigerants and energy efficiency. And finally, workforce regulation changes and increasing labor costs will lead retailers to look to additional technology and automation for solutions.

Read the full article in Convenience Store Decisions here.

And to learn about five emerging trends for supermarket retailers, read this blog post.

Mark Dunson
President, Retail Solutions
Emerson Climate Technologies

Progress Report: Sustainability, Energy Efficiency Commitments Met; New Goals Set

A short 18 months have passed since the EPA proposed its delisting rule regarding today’s refrigerants. At that time, members of Emerson Climate Technologies’ senior team attended a symposium at the White House to discuss ways to mitigate the negative impacts of HVACR technology on the environment. The meeting concluded with all parties pledging to take steps to reduce global warming, and we laid out Emerson’s specific plan to do just that. I am pleased to report that we have kept our promise.

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As a company known for our proactivity and planning, we were already well down the path of formalizing many sustainability initiatives, and the specific commitments we made were aligned with those objectives. First, we committed to the construction of a global industry-accessible innovation center that would take on the biggest environmental and energy efficiency challenges affecting food retail, foodservice, commercial and residential buildings, and data centers. On December 17, 2015, the Helix Innovation Center opened on the University of Dayton campus, where we are beginning these pursuits toward a next generation of technologies.

Second, we committed to complete the development of several new products optimized for low-GWP refrigerants as well as expand upon our efficient and sustainable CO2, propane and ammonia product lines. I am happy to report that we successfully developed new compressors, controls and flow components in 2015, utilizing natural and low-GWP synthetic refrigerants that are viable replacements for traditional HFC applications. We also advanced our condensing units built around these class-leading core technologies, launching new products that enable significantly higher efficiencies while meeting refrigerant needs.

Our industry witnessed a whirlwind of regulatory activity in 2015, and these rulings are likely to continue throughout the near future. With the Helix Innovation Center open for business, it enhances our capability to collaborate with the entire value chain and respond to these requirements as they emerge. We’ve learned through the development of these products that as an industry of contractors, wholesalers, OEMs and consultants, we are all seeking to better understand how to apply and service new installations and manage the existing installed base of systems.

That is why we are even more committed to accelerating the E360 stewardship and exchange platform. To date, nearly 6,000 industry leaders and professionals have registered for these events. We are dedicated to hosting an objective forum — a place where ideas are presented and the challenges we face throughout the channel can be discussed and solved.

In October of 2015, the White House invited us to a follow-up meeting to report on our progress. While we were extremely pleased to present these accomplishments, we also pledged our ongoing commitment. It is our strong belief that environmental protection, global understanding of these sustainability measures and continued industry participation are all required to meet our shared challenges and objectives. Emerson Climate Technologies is dedicated to continuing its support for these efforts through our commitment to providing innovative products and ongoing industry stewardship.

Bob Sharp
Executive Vice President and Business Leader
Emerson Climate Technologies


This blog originally appeared in our recent edition of E360 Outlook. Click here to read the issue in its entirety.

Changing Regulations to Impact Retail Businesses

In the January issue of Chain Store Age, we discussed government regulations that will affect supermarket and convenience store retailers in 2016. Below are the highlights:

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In 2016, retail chains will continue to face increasing competition and high consumer expectations. Changing regulations will also impact retail businesses. We see three regulatory issues as the most critical for the retail industry this year and beyond:

  1. Food Safety Modernization Act (FSMA)
    For retailers offering fresh foods, FSMA will have an impact on food integrity and safety, and may help with reducing food waste. As retailers focus more on “farm to table” freshness, the result will be an increased importance on collecting and utilizing data related to the safety and integrity of foods.
  2. Refrigerant and energy efficiency standards
    The EPA and DOE are working diligently with industry leaders to decrease greenhouse gas emissions, move to climate-friendly refrigerants and employ advanced refrigeration technologies. Most of these technologies are not “drop-in” substitutes for retrofitting. Retailers and their suppliers will need to plan and collaborate to fulfill all guidelines.
  3. Changing workforce regulations
    Retailers will continue to deal with employment and workforce regulation changes. Increasing labor costs will lead retailers to look to additional technology and automation for solutions.

You can read the full Chain Store Age article on page 26 of the January print issue.

 What regulations will impact you most in 2016? Please share your insights in the comments below.


Mark Dunson
President, Retail Solutions
Emerson Climate Technologies

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