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Natural Refrigerants Remain Viable Among Emerging Options

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

Emerson Commercial & Residential Solutions

I was recently asked by the editor of Accelerate America to offer my opinion on the viability of natural refrigerants, including CO2 (R-744), propane (R-290) and ammonia (R-714). Among the many emerging refrigerant alternatives, natural refrigerants check important boxes for owners and operators who are preparing for the rapidly changing commercial refrigeration landscape. View the full article here and read a summary of its key points below.

For more than a decade, natural refrigerants have factored prominently in the search for environmentally friendly refrigeration in both commercial and industrial sectors. We’ve seen the introduction of R-290 in micro-distributed, self-contained cases; increased global adoption of CO2 in centralized systems; and the emergence of ultra-low-charge ammonia, by itself as well as integrated with CO2 in cascade systems. As we kick off a new decade, we will likely continue to see these refrigerants progress along those established lanes.

Drivers for natural refrigerant adoption

Since their introduction, the drivers for natural refrigerant adoption have not changed. Most legacy refrigeration strategies rely on the use of high global warming potential (GWP) hydrofluorocarbon (HFC) refrigerants, and companies with sustainability objectives or regulatory mandates were among the first to make the transition to natural refrigerants — which by many are considered immune from regulatory-mandated GWP caps.

In 2020, the phase-down of HFCs remains a focus of global environmental regulations. From the Kigali Amendment to the Montreal Protocol and the European F-Gas regulations to the California Air Resources Board (CARB) and Environment and Climate Change Canada (ECCC), many countries, states and regions share the goal of an HFC phase-down.

It’s often said that there’s no such thing as a perfect refrigerant — and that’s certainly the case with natural options. But natural refrigerants are among the very few alternatives capable of meeting some of the more aggressive GWP targets. R-290 has a GWP of 3; CO2 has a GWP of 1; and ammonia has a GWP of 0. So from environmental and regulatory perspectives, this puts them in a class by themselves.

Characteristics and caveats

With decades of field use and research to draw from, the performance characteristics of natural refrigerants are well known. But each option has operating caveats that equipment owners must carefully consider before investing in a long-term refrigeration strategy.

  • R-290 offers excellent energy efficiencies, but as an A3 (flammable) refrigerant, safety regulations limit its use to small charges globally from 150g to 500g. R-290 is a natural fit for small-capacity, self-contained cases that require a lower charge and are hermetically sealed at the factory.
  • CO2 is a high-pressure refrigerant with a low critical point (87.8 °F) that determines its modes of operation (subcritical, or below the critical point; transcritical, or above the critical point). It also has a high triple point where the refrigerant will turn to dry ice. Systems must be designed to manage these characteristics, and operators must have access to qualified technicians.
  • Ammonia has been used in industrial refrigeration for the past century, but its toxicity (B2L classification) presents challenges to equipment owners. Tightening safety regulations and the risk of exposure have led to system architectures designed to lower charges and move it out of occupied spaces.

Selecting a natural architecture

When evaluating natural refrigerant architectures, store formats and application requirements will often dictate the refrigerant choice. R-290 is well-suited for either smaller-format stores or as a spot merchandising option for larger stores. CO2 makes the most sense in larger stores seeking a centralized architecture alternative to HFCs. Ammonia is relatively rare in commercial applications but is finding its way into innovative architectures designed to mitigate its risks and benefit from its excellent performance characteristics.

R-290, from integrated cases to micro-distributed — For nearly a decade, manufacturers have worked within the 150g charge limit to create self-contained, integrated cases, in which the refrigeration system (compressor and condensing unit) is built into the display case. These evolved into a micro-distributed approach for small stores, where multiple units share a water/glycol loop to remove excess heat. This approach provides very low-GWP, total-store cooling while keeping charges low, typically operating with 90% less refrigerant than a centralized system.

CO2 transcritical booster — CO2 came into prominence more than a decade ago in large supermarkets where centralized architectures are preferred. CO2 transcritical booster system technology continues to improve today, offering an all-natural solution for both low- and medium-temperature cooling. Compared to centralized HFC systems, CO2 transcritical boosters represent a completely different approach to system operation and servicing. Operators must acquire technicians that are trained to service CO2 systems and implement strategies for power outages in order to mitigate “stand-still” pressure while the system is off.

CO2/ammonia hybrid subcritical (cascade) — CO2 cascade systems are designed to utilize CO2 in the low-temperature (LT) suction group where the refrigerant stays below its critical point and operates at lower pressures, much like a traditional HFC. Typically, an HFC (or HFO/HFC blend) is used in the medium-temperature (MT) circuit, where heat produced from the LT circuit is discharged (i.e., cascaded) into a heat exchanger and into the suction stage of the MT circuit. However, the recent introduction of ammonia as the MT refrigerant has transformed this configuration into an all-natural refrigerant option.

Safety first

With each of these natural refrigerant options, safety must be the primary consideration. Manufacturers have poured a great deal of effort into ensuring the safe operation and maintenance of natural systems with a variety of strategies, including pressure relief valves, specially designed components, leak detection devices, and proper guidance to owners and operators.

The global regulatory climate and trend toward environmentally friendly refrigeration will help natural refrigerants to proliferate along these well-established paths of least resistance. Still, there is much to consider for system operators, who must weigh the opportunity costs for selecting a natural refrigerant option.

 

Why Contractors Need to Prepare Now for the Coming CO2 Refrigerant Revolution

DonGillis Don Gillis | Technical Training Specialist

Emerson Commercial & Residential Solutions

CO2 is an emerging natural refrigerant alternative, but it poses a sharp learning curve for technicians in the U.S. I recently authored an article in RSES Journal that explains why contractors will need to start enhancing their knowledge and adapting their skillsets now to prepare for future servicing needs. You can read the full article, “Fundamentals of CO2 Refrigeration,” here.

Why Contractors Need to Prepare Now for the Coming CO2 Refrigerant Revolution

Why Contractors Need to Prepare Now for the Coming CO2 Refrigerant Revolution

As the drive to replace hydrofluorocarbon (HFC) refrigerants with lower-GWP (global warming potential) alternatives heats up, CO2 (or refrigerant R-744) is a proven natural option that is experiencing wider adoption in the U.S. — particularly in large centralized systems.

Natural refrigerants — so named because they occur naturally in the environment — also include both propane and ammonia. But for larger-format supermarket operators seeking an all-natural, environmentally friendly option, CO2 checks all the boxes. It’s nonflammable and nontoxic. It presents no threat to the ozone layer. And it meets every current and known future regulatory requirement. In addition, whereas R-404A has a GWP of 3,922, CO2 has a GWP of 1.

While CO2 refrigeration architectures have been successfully deployed in European commercial and industrial settings for nearly two decades, they are a relative newcomer to the U.S. That’s set to change as more operators face regulatory mandates or have stated sustainability objectives.

This will pose a sharp learning curve for many refrigeration contractors and service technicians, especially those who aren’t familiar with the peculiarities of CO2, or the transcritical CO2 booster architecture they’re most likely to encounter soon.

Understanding CO2’s unique properties

When servicing transcritical CO2 booster systems, technicians will need to account for factors that they have never needed to consider with HFC systems. CO2 has a much lower temperature at atmospheric pressure than HFCs. It also has a higher saturation point, as well as higher operating and standstill pressures. Understanding how these characteristics impact system operation servicing requirements and system performance is essential:

  • Low critical point. CO2’s very low critical point (at 1,056 psig or 87.8 °F) determines its modes of operation; the system will operate in subcritical mode at low ambient temperatures and transcritical mode at higher ambient temperatures.
  • High triple point. At 61 psig, CO2’s triple point — where the refrigerant’s solid, liquid and vapor phases coexist — is very high. If system pressures reach the triple point, the refrigerant will turn to dry ice, which affects system performance and presents a potential safety hazard.
  • Rapid pressure rise. During power outages, CO2 pressures can rise quickly. Pressure-relief valves will release the refrigerant charge when it exceeds acceptable pressures, but this can increase the risk of product loss. To prevent system evacuation, CO2 systems often are designed with an auxiliary cooling system.
  • Vapor to liquid charging. CO2 systems typically use both liquid and vapor to charge, requiring careful coordination to prevent the formation of dry ice.

Transcritical CO2 systems are specifically designed to manage its high pressures and maximize its full potential. Because this system design represents a completely different approach than typical HFC systems, specialized training is required to service these systems and understand their supporting technologies, which typically include high-pressure controllers, electronic expansion valves, pres­sure transducers and temperature sensors.

Finding the right educational resources

Contractors and technicians who want to add CO2 servicing to their qualifications would do well to start educating themselves now. All signs indicate that its adoption in the U.S. will accelerate in the near future. Given CO2’s peculiarities and unique system design strategies, it is imperative that technicians familiarize themselves with the refrigerant and the operation of a CO2 system.

At Emerson, we are leading the industry in CO2 refrigeration system innovation. But we don’t just offer a full suite of CO2 refrigeration system components. We also are dedicated to helping contracting businesses ensure their service technicians understand how to safely install, commission and service these systems. Our Educational Services team offers a comprehensive CO2 training curriculum for contractors seeking to learn more about working with this emerging refrigerant alternative.

 

Earth Day and Refrigerants: A Look Back — and Forward

Jennifer_Butsch Jennifer Butsch | Regulatory Affairs Manager

Emerson Commercial & Residential Solutions

It’s Earth Day, which means we should all take a minute to reflect on how we can do our part to make the planet a greener place. In the world of commercial refrigeration, environmental initiatives and sustainability best practices typically focus on limiting the harmful effects of hydrochlorofluorocarbon (HCFC) and hydrofluorocarbon (HFC) refrigerants. When these refrigerants leak into the atmosphere via direct emissions, their environmental impacts can be measured in terms of ozone depletion potential (ODP) and global warming potential (GWP).

But when considering the total equivalent warming impact (TEWI) of commercial refrigeration systems, direct emissions are only part of the equation. TEWI also considers indirect impacts, or the greenhouse gases generated from the energy consumed to run these systems — estimated to represent as much as 95 percent of the total climate impact. At Emerson, we take both energy efficiency and refrigerant GWP into consideration to evaluate the full lifecycle climate performance (LCCP) of a system and its fluids.

Montreal Protocol to complete R-22 phaseout

Today, most global refrigerant regulations are focused on phasing down high-GWP HFCs. But it’s important to remember that these activities have a precedent that’s more than three decades old. In 1987, the Montreal Protocol treaty aimed to phase out ozone-depleting substances (ODS), such as the commonly used HCFC, R-22. This global treaty was since ratified by 197 countries, including the United States, Canada and Mexico, all of whom have followed its recommended phaseout schedule.

The next step in this process will take place in 2020, when the production and import of R-22 will no longer be allowed under the Environmental Protection Agency’s Clean Air Act. It may come as a surprise to some, but there are still untold operators with older refrigeration systems that are currently charged with R-22. Unlike smartphones and other commodities that we change or upgrade every year,  commercial refrigeration equipment can have a lifespan of 20 to 30 years. This phaseout will likely lead to an increase in system retrofits in the near term, especially as operators exhaust their supplies of R-22.

Thankfully, there’s a good deal of evidence that since the removal of ozone-depleting substances from the environment began, the ozone layer is on the mend. Some estimates state that the ozone hole above Antarctica could close by the 2060s.

HFCs targeted for global warming potential

As the HCFC phaseout began decades ago, the industry transitioned to HFCs with very low ODP. Unfortunately, many of these have since been discovered to have varying degrees of GWP. In fact, the most common HFC used in commercial refrigeration is R-404A, which has a GWP of 3,922 and is considered on the high end of the GWP scale. It’s no surprise then that it was among the first refrigerants to be targeted for phasedown under the EPA’s Significant New Alternatives Policy (SNAP) rules 20 and 21.

But per the 2018 ruling by the U.S. Court of Appeals, the EPA no longer has the authority to regulate the use of refrigerants based on their GWP under the framework of the Clean Air Act. While we expect the EPA to soon provide clarity on the future of its HFC initiatives, there currently is no federal mechanism through which the proposed phasedown of high-GWP refrigerants will take place.

In the meantime, California has adopted the original EPA SNAP framework into law, and as of January 1, R-404A and R-507A are no longer allowable in many new commercial refrigeration applications. California is just one of 23 states or territories in the U.S. Climate Alliance that are making commitments to enforce similar climate protection initiatives. Currently, this growing alliance represents half of the U.S. population and more than 50 percent of the national GWP.

Globally, the Kigali Amendment to the Montreal Protocol seeks to expand the treaty’s scope from just ozone protection to addressing global warming by phasing down short-lived climate pollutants, including HFCs. While this amendment has yet to be ratified by the United States, it has achieved the required ratification of 20 member countries to take force — including Canada and the United Kingdom, among others. For participating countries, the Kigali Amendment took effect on January 1.

Exploring the alternatives

Because regulatory variances occur from state to region to country, there are vastly different levels of environmental awareness throughout our industry. While operators in California are cognizant of the state’s efforts to phase down HFCs, there are many U.S. areas where transitioning to lower-GWP refrigerants isn’t as high of a priority.

Regardless, many top retailers have begun the process of exploring low-GWP refrigerant options as part of their sustainability objectives. Not only do they have retrofit plans in place, some are even trialing alternative refrigerant architectures in their stores — with hydrofluoroolefins (HFOs), HFO/HFC blends and natural refrigerants as leading options.

There are relatively minimal retrofit requirements when moving from R-404A to R-448A/R-449A — both A1 HFC/HFO blends — such as adding compressor cooling and other minor system changes. For a greenfield location or a complete system overhaul of an existing site, operators may consider one of many emerging low-GWP options, including:

  • Low-charge ammonia chillers on the roof
  • A2L (mildly flammable) blends in chillers on the roof and machine rooms
  • Distributed, small-charge systems with both A1 and A2L refrigerants
  • R-290 integrated cases outfitted with micro-distributed systems
  • CO2 transcritical and/or cascade systems using CO2 for low temperatures, and an HFO (or lower-GWP HFC) for medium temperatures

 

Refrigerant management best practices

As always, proper refrigerant management practices are important, regardless of the type of refrigerant used. Operators should start with a documented leak detection plan that includes the necessary tools and early-detection methods to identify and quickly respond to leaks. Leaks are not only bad for the environment; they also degrade refrigeration performance and system energy efficiencies.

With the new class of refrigerants, it’s especially important that technicians are trained to understand proper handling, charging and performance characteristics. In addition, as systems charged with higher-GWP HFCs eventually reach the end of their lifespans, it’s critical that service technicians follow proper recovery and disposal protocols.

Earth Day is a good time to reflect on the environmental progress our industry has made. At Emerson, we’ll continue to support sustainability objectives with compressors, components and systems that are both environmentally responsible and economically viable.

Top 10 Emerson YouTube Videos for 2018: Lights, Camera, Expertise!

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

Emerson Commercial & Residential Solutions

At Emerson, seeing is explaining. When you need to keep pace with new technologies, regulations and ideas in fast-moving industries, you want to hear from the experts. That’s why we regularly call upon industry leaders to join us in discussions about the future of our commercial refrigeration industry. You can find many of these discussions in videos captured from informative E360 Webinars and Forums. What follows is a summary of our top 10 most-viewed videos of 2018.

  1. E360 Webinar 13: Seven Keys to Servicing CO2 Systems

CO2-based refrigeration systems with R-744 are new to a lot of service technicians, which drew a large audience to this webinar about dealing effectively with the refrigerant’s unique properties. Starting with an overview of the systems themselves, the presentation walked step-by-step through handling critical and triple points, high and standstill pressures, cylinder storage, charging and system maintenance best practices.

  1. E360 Forum: Dallas | Food Industry Forecast: Key Trends Through 2020

After a long period of stable growth, the restaurant, foodservice and food retail industries face a set of new and disruptive industry trends, with new business structures, different operating environments and business practices that are rapidly driving change. This E360 Forum discussed these big trends: new consumer expectations, the demand for localized food, farm-to-fork transparency, the role of technology and Big Data, and deconsolidation into specialized niches.

  1. E360 Forum: Raleigh | Cold Chain Evolution

The pressure to create an unbreakable global cold chain has become critical for the food industry. Every year, 33 percent of all food spoils in transit — a loss of $1 trillion. Food safety is critical to a brand’s reputation, trust and profits. Global transport and international regulations have extended the cold chain to air, land and water. This E360 Forum discussed the cold chains of yesterday and today, and described how the rapid evolution to a digitally connected cold chain provides the potential for end-to-end optimization.

  1. E360 Webinar 6: Best Practices for Evaluating Compressor System Performance

Whether you’re a commercial refrigeration OEM selecting a compressor for a new system or a food retailer choosing a new chiller, there are a lot of compressor options from which to choose, often with very different performance attributes to consider. This popular webinar discussed factors such as temperature mid-points and dew points, compressor capacities, energy-efficiency ratios and other issues crucial to selecting the right compressor with the lowest cost of ownership.

  1. E360 Webinar 14: EPA’s Final Refrigerant Ruling: Its Impact on Your Business

The EPA’s 2015 final rule on the delisting of HFC refrigerants in commercial refrigeration and AC applications sent shockwaves throughout our industries. This webinar detailed which refrigerants were selected for phase-down and when, discussed how the ruling impacted various refrigeration applications, and covered viable refrigerant alternatives for OEMs, operators, and refrigerant manufacturers and contractors. For the latest rulemaking on refrigerants, please view this regulatory update session from our most recent E360 Forum.

  1. E360 Conference 2017 | Trends in Supermarket Refrigeration Architectures

If they haven’t already, the architecture, systems and refrigerants in your supermarket are going to change — significantly. Driving the change? The drumbeat of international, federal and state regulations already arriving. This high-level conference covered a wide range of architectures, equipment and refrigerant options, their complexity, costs and maintenance requirements, and four key operational considerations: energy, economics, the environment and equipment.

 

  1. E360 Forum: Anaheim | Trends in Refrigerant System Architecture & CO2

As ambient temperatures go up, condenser and refrigerator compression efficiency go down. With new refrigerants, including natural refrigerants such as CO2, high temperatures — and the refrigerants’ critical points — become major considerations. In this technical presentation, centering on CO2 refrigerant as an example, we discussed a range of system architecture options and new equipment and components that help CO2 refrigeration tackle high ambient temperatures while maintaining performance.

  1. E360 Webinar 16: Innovation in Refrigeration

This webinar’s short title encompasses the enormous problems facing our industry today, including: dynamic regulations, the need for an unbreakable global cold chain, the call for access to all data, and the needs of a rapidly changing industry. In this webinar, we learned that the process of innovation itself has to evolve to involve every link in the refrigerated equipment value chain. You’ll see these new approaches modeled at The Helix Innovation Center at the University of Dayton in Ohio, where we’re actively pursuing innovations in refrigeration technology through an inclusive, collaborative approach.

  1. E360 Conference 2017 | The Human Equation of Facility Management

This is a story about shortages. Facility managers have a shortage of resources across the board and sometimes have to outsource their facility services. These services face a shortage of technicians — and a big gap in expertise between experienced technicians and the new generation. Under these circumstances, how do you manage costs and ensure efficient responses to facility problems? This conference presented an answer: call on technology to become more intelligent and provide technicians the information they need to do more with less.

  1. E360 Forum: Anaheim | Converting Waste Into Renewable Energy

Ever give a thought to the garbage disposal in your kitchen sink? This presentation showed that it’s no longer a simple appliance, but an environmentally responsible tool that keeps food waste out of landfills, keeps methane out of the air, and creates a new, clean energy source — right from the food scraps going down your sink. InSinkErator, an Emerson company, works to transform water treatment plants into energy powerhouses by creating biosolids to produce energy and fertilizers without waste.

 

Mobile CO2 Booster Transcritical Training Unit Launches North American Tour

Liborio Mendola Liborio Mendola | Product Planner
Emerson Commercial & Residential Solutions

Emerson’s new CO2 Booster training unit is preparing to make several stops across the U.S. and Canada in 2019. Learn more about what this hands-on experience will offer attendees.

Adoption of the natural refrigerant CO2 (R-744) in commercial and industrial refrigeration applications is on the rise in North America and around the globe. With 0 ozone depletion potential (ODP) and a global warming potential (GWP) of 1, CO2 is considered the environmental standard by which other refrigerants are measured. But with its high operating pressures and unique performance characteristics, industry stakeholders have many questions about how to design, operate and service a CO2 system. That’s why Emerson is pleased to introduce its new, mobile CO2 Booster training unit.

The CO2 training unit is designed to give contractors, manufacturers, wholesalers and end users a hands-on experience and learn what it’s like to work on a CO2 refrigeration system. Launched in Canada in September, the unit has already visited locations in Quebec and trained more than 50 contractors. In early 2019, the unit will travel to the U.S. and make several stops, starting with an appearance in the Atlanta area timed to correspond with the conclusion of the AHR Expo. The current schedule is as follows:

  • January 16–17: Atlanta, Ga.
  • January 30–31: Orlando, Fla.
  • February 13–14: Rancho Cordova, Calif.
  • February 27–28: Elmsford, N.Y.
  • March 20–21: Cudahy, Wis.
  • April 10–11: Brantford, Ont.

Each stop will feature a two-day training session designed to accommodate 20 attendees and cover a wide range of CO2-related topics, including:

  • Subcritical vs. transcritical modes of operation
  • Overview of CO2 system architectures
  • Safe handling, maintenance and charging
  • Startup and shutdown sequences

Become familiar with CO2 and refrigeration system components

The open 360° view of the training unit allows attendees to familiarize themselves with the refrigerant and the components which make up a CO2 system. To demonstrate the volatility of CO2, the unit includes a phase change cell that shows how the refrigerant reacts to pressure changes. Starting in its liquid state, R-744 is subject to increasing pressures and begins its transition into a vapor state, then to a supercritical fluid, until it ultimately becomes a transparent gas. Then, as pressure is dropped within the cell, attendees can see the reverse of this transition as CO2 returns to a liquid state and then forms into a solid piece of dry ice.

The CO2 Booster training unit utilizes a full Emerson system that includes: low- and medium-temperature compressors, electronic controls, protectors, variable-frequency drives and transcritically rated electronic expansion valves. For ease of use, the unit is designed to improve the visibility of all components and dial gauges to demonstrate pressures and temperatures of certain elements.

The transportation container is designed for simplified transport and protection against the rigors of over-the-road travel. This container is also equipped with Emerson’s Cargo Solutions that allow live tracking of the unit’s location, ambient temperature and other conditions through Emerson’s Oversight app.

Registration for scheduled two day sessions is now open. The cost is $700 per person and includes all course materials, breakfast and lunch.

If you’re interested in learning more about CO2, be sure to reserve your spot (Class Title: CO2 Refrigeration) at an upcoming training session.

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