Emerson’s Commercial & Residential Solutions Business
As we near the mid-point of 2022, it’s clear that the global phasedown of hydrofluorocarbon (HFC) refrigerants is gaining momentum and impacting U.S. commercial refrigeration and HVAC markets. In our next E360 Webinar, Dr. Rajan Rajendran, Emerson’s global vice president of environmental sustainability, and I will overview the latest updates to refrigerant regulations and safety standards. This webinar will take place on Tuesday, June 21 at 2 p.m. EDT/11 a.m. PDT.
Throughout the HVACR industry, stakeholders are evaluating their next-generation refrigeration strategies and making plans to transition to lower-global warming potential (GWP) alternatives. Regardless of where your company is on this journey, keeping up with the latest regulatory developments is critical to making informed decisions. Considering that most HVACR equipment is expected to last from 10 to 20 years, it’s imperative to explore equipment strategies that not only stand the test of time, but also align with your operational and sustainability goals. Understanding how regulations are driving the evolution of refrigeration technologies is key to making these important decisions.
If you’ve been following the progression of refrigerant regulations for the past several years, it may have seemed like the HFC phasedown and subsequent transition to lower-GWP refrigerants were faraway concerns that didn’t apply to U.S. stakeholders — except maybe for those operating in California or other Climate Alliance states. Today, that’s simply not the case.
Federal mandates are taking shape that will soon impact all U.S. stakeholders. Equipment standards that govern the safe use of A2L and A3 refrigerants are quickly evolving. Making environmental stewardship pledges at the corporate level has become a much higher priority. Complying with refrigerant regulations, selecting eco-friendly alternatives and meeting corporate sustainability objectives are quickly becoming shared concerns for most U.S. stakeholders.
E360 Webinar presents path forward
To help you find a path forward on your low-GWP refrigerant journey, Rajan and I are hosting a new E360 Webinar that will explain the latest regulatory updates and provide recommendations for next steps. Attendees will learn:
Ongoing progress of the American Innovation and Manufacturing (AIM) Act and its impacts on Environmental Protection Agency (EPA) rulemaking
Status of California Air Resources Board (CARB) refrigerant mandates that went into effect in 2022
Update on the safety standards and codes impacting flammable A3 and A2L refrigerants
Tips for preparing for the next generation of alternative refrigerants
Emerson’s Commercial and Residential Solution’s Business
The transition from hydrofluorocarbon (HFC) refrigerants to lower-global warming potential (GWP) alternatives has become a common denominator in many food retailers’ sustainability strategies. Whether your company is in the early phases of its sustainability journey or has already made significant progress in the race to Net Zero, you’ve likely evaluated the potential of CO2-based refrigeration. Among the many misperceptions about CO2 transcritical booster systems is that they are not well-suited for installations in warmer climates. Emerson recently partnered with Zero Zone to help a leading food retailer prove the business case for warm-weather CO2 refrigeration. To view the full article, click here.
Expanding application potential
When calculating the sustainability potential of a refrigeration system, it’s important to look at its total equivalent warming impact (TEWI), including direct carbon emissions from refrigerant leaks and indirect emissions from energy consumption. Although the natural refrigerant CO2 (or R-744) has a GWP of 1, many supermarket owners and operators have questions about the efficiency of CO2 transcritical booster systems, especially in warmer climates.
CO2 transcritical booster refrigeration systems have been installed in Europe for decades and are expanding rapidly around the globe. Today, nearly 1,000 CO2 transcritical booster systems are installed in the U.S., with adoption projected to increase more than 50% by 2025. System designers, original equipment manufacturers (OEMs) and component manufacturers (e.g., Emerson) have made tremendous strides in developing smart CO2 transcritical booster system strategies that:
Improve energy efficiencies in warmer climates
Optimize system performance and reliability
Lower the total cost of ownership (TCO)
Simplify system start-up, operation, high-pressure management and maintenance
Retailers who are now looking at CO2 for the first time will benefit from years of installations and supermarket trials that have significantly improved upon CO2 transcritical booster equipment technologies.
Proving the business case
In a recent collaboration, Emerson partnered with refrigeration OEM Zero Zone to help them design and install a CO2 transcritical booster system for a new supermarket in Joplin, Mo. Due to the location’s warm climate, the design team recommended an emerging high-ambient mitigation strategy designed to maximize the efficiency of CO2 during the summer season. The goals of the project were to help the retailer to meet their sustainability targets while maintaining the highest standards for food quality and safety.
The climate in Joplin averages more than 200 annual hours above R-744’s critical point of 87.8 °F. During these warmer temperatures, a CO2 transcritical booster system would typically enter transcritical mode and consume electricity at a higher rate, but the Emerson and Zero Zone system has been designed to operate efficiently across even these high-temperature ranges. With recent advances in system technologies, stakeholders can choose from multiple CO2 strategies designed to mitigate high-ambient temperatures, minimize transcritical operation, and maximize energy efficiencies.
For the Joplin installation, Zero Zone and Emerson opted to utilize an adiabatic gas cooling strategy on the system’s outdoor condenser/gas cooler. When summer heat builds and R-744 pressures begin to rise within the gas cooler, water is misted onto adiabatic cooling pads — effectively keeping R-744 below its critical point during warm stretches and dramatically improving system efficiency. Today, this installation is operating as designed for Zero Zone’s food retail customer, delivering year-round efficiencies and refrigeration reliability.
The system features a full suite of integrated Emerson CO2 technologies — from low- (LT) and medium temperature (MT) compressors to CO2 refrigeration rack controls case controls and high-pressure controls — that are helping Zero Zone to prove the business case for warm-climate CO2 systems. Not only have these technological advances greatly expanded the potential of CO2 applications in diverse climates, but they’re accelerating CO2 adoption for a new generation of end-users and service technicians.
For more information about the high-ambient CO2 mitigation strategy used in this installation, you can read our case study. To learn about Emerson’s commitment to developing integrated CO2 technologies, please visit our CO2 information hub.
Emerson’s Commercial & Residential Solutions Business
If you’re like many stakeholders in the commercial refrigeration industry, you know how important it is to keep track of the dynamic regulatory climate. From making refrigerant decisions and selecting next-generation equipment to plan for compliance and meeting sustainability goals, many companies are basing some of their most important decisions on these developments. I recently provided an article to HVACR Business that reviewed several key regulatory updates taking place this year. If you’re hoping to bring the sometimes-confusing regulatory picture into clearer focus, hopefully this will help. You can also view our formatted article here.
AIM Act establishes federal HFC legislation
Signed into law in late 2020, the American Innovation & Manufacturing Act (AIM Act) gave the Environmental Protection Agency’s (EPA) authority to regulate hydrofluorocarbon (HFC) refrigerants in three primary ways:
Phasing down HFC refrigerant supplies by reducing their production and consumption over a 15-year period. Supply-side restrictions began on Jan. 1, 2022, requiring a 10% reduction in HFC production and consumption through 2023. An additional 30% reduction will take effect between 2024 and 2028 with 70% and 80% reductions needed by 2029 and 2034, respectively. These phasedowns are expected to drive up HFC prices significantly as supplies decrease.
Establishing sector-based approvals and HFC restrictions to support the industry-wide transition to lower-global warming potential (GWP) refrigerant technologies. Use restrictions will enable specific sectors to transition more quickly while providing additional flexibility for those who may need more time. The EPA can approve new lower-GWP alternatives per sector-based rulemakings, which are expected to begin in 2022.
Regulating HFC management by establishing and enforcing standards in servicing and repair best practices, such as: lowering leak rate thresholds and requiring proper recovery of “used” HFCs for purification and resale (aka reclaim). Previously, the EPA had created Section 608 to govern these best practices; we expect their revised HFC management rulemaking could be built off the Section 608 framework.
CARB rulemaking takes effect
After several years of collaboration with state and HVACR industry stakeholders, the California Air Resources Board’s (CARB) proposed rulemaking became final in late 2021 and went into effect on Jan. 1, 2022. The final rule establishes HFC phasedown requirements for new and existing facilities, including a company-wide provision for food retailers operating with a fleet of existing stores within California.
New facilities — Installation of new refrigeration systems containing more than 50 pounds of refrigerant are required to use refrigerants with less than 150 GWP.
Existing facilities — Refrigeration equipment containing more than 50lbs of refrigerant in existing facilities are subject to company-wide, fleet GWP reduction targets by 2030 compared to their 2019 baselines — with two potential paths to compliance: 1) Weighted-average GWP (WAGWP) reduction <1,400 GWP by 2030, where WAGWP is the sum of the total refrigerant charge of every system greater than 50 pounds in every store in California; 2) Greenhouse gas emissions potential (GHGp) reduction by 55%, where GHGp is the sum of the total refrigerant charge of every system greater than 50 pounds in every store in California multiplied by the GWP values of the refrigerant types in use.
Regarding new stationary air conditioning (AC) equipment, refrigerants with a GWP greater than or equal to 750 will be prohibited, starting in 2025.
Evolving safety standards for flammable (A3) and mildly flammable A2L refrigerants
Governing bodies that regulate the safe use of refrigerants in the U.S. have long been evaluating the prospect of increasing charge limits in the flammable A3 (propane, aka R-290) and mildly flammable A2L refrigerants. In 2021, the Underwriters Laboratories (UL) approved the second edition of its UL 60335-2-89 standard, which included higher charge limits that would expand the potential uses of R-290 and A2Ls in commercial refrigeration.
R-290 charge limit increases — R-290 has a long-held maximum charge limit of 150g and has primarily been used in smaller, self-contained units. The updated UL standard raises the charge limits on these commercial stand-alone displays based on whether they have an open or closed design:
500g maximum charge limit in open appliances (without doors)
300g maximum charge limit in closed appliances (with doors or drawers)
From an application design perspective, higher charge limits will help to increase system capacities while capitalizing on R-290’s high efficiency and low-GWP rating (GWP = 3).
A2L charge limit increases — Per the recently updated UL 60335-2-89 safety standard, new A2L charge limit guidelines have been established for self-contained and remote refrigeration systems. For self-contained equipment, charge limits are determined by equipment design (e.g., open or closed with doors or drawers). Degrees of flammability will vary among different A2L refrigerants, so it’s important to calculate charge limits based on the specific A2L characteristics.
For example, R-454C has a lower flammability limit (LFL) of 0.291 kg/m3, thus:
A closed-door case can be charged with up to 2.33 kg (5.1 lbs.) of R-454C.
An open case with R-454C can be charged with up to 3.78 kg (8.3 lbs.) of R-454C.
In remote or field-erected systems, UL 60335-2-89 supports R-454C charge sizes up to 75.7 kg (166 lbs.) per circuit.
The updated standard requires remote A2L systems to be designed with requisite safety strategies and mitigation measures to keep gas concentrations below flammable thresholds:
Leak detection at various points of the refrigeration circuit (e.g., compressor, condensing unit and case)
Action plans that immediately mitigate flammability risks
The UL 60335-2-89 second edition update is only the first step in a larger series of regulatory approvals needed to enable higher charges of R-290 and the use of A2Ls in U.S. commercial refrigeration. Additional regulatory and/or policy changes will also need to be approved:
EPA Significant New Alternatives Policy (SNAP) approval of specific A2L refrigerants and increased R-290 charge limits
ASHRAE 15 safety standard update for refrigeration systems
Model code updates in the upcoming code revision cycle, such as: Uniform Mechanical Code (UMC), International Mechanical Code (IMC) and International Fire Code (IFC)
State and local building code updates
In the meantime, installing an A2L-based refrigeration system would typically require the approval of local authorities having jurisdiction (AHJ), such as fire marshals and/or building inspectors.
To stay informed of the latest regulatory updates that could impact your operational decision-making, please visit our regulations hub.
Emerson’s Commercial and Residential Solution’s Business
Until recently, CO2 refrigeration systems in the U.S. have been perceived as exceptions to the rule in commercial refrigeration. But as corporate sustainability initiatives and refrigerant regulations continue to reshape refrigeration decisions, many supermarket retailers are exploring CO2’s long-term potential. I recently contributed an article for Supermarket News in which I examined the regulatory, market and technological trends behind its increased adoption in the U.S. To view the full article, click here.
To date, most CO2 installations in the U.S. have been deployed as proofs-of-concept. Although there are some sustainably-minded retailers that have made it the basis of their refrigeration strategy, CO2 hasn’t yet experienced the industry-wide acceptance we’ve seen in Europe. But that appears to be changing.
Among the environmental strategies identified to combat climate change, the greening of commercial and industrial refrigeration equipment has been recognized as an essential tactic of decarbonization plans and corporate sustainability initiatives. Food retail stakeholders are rethinking their approaches to refrigeration and transitioning away from legacy hydrofluorocarbon (HFC) refrigerants with high global warming potential (GWP). More than ever, retailers are evaluating long-term refrigeration strategies that support:
Environmental, social and governance (ESG) efforts
Energy efficiency and emissions reductions targets
Stage is set for wider adoption
With zero ozone depletion potential (ODP) and a GWP of 1, the natural refrigerant CO2 (aka R-744) is a proven alternative to higher-GWP HFC refrigerants. CO2’s inherent energy efficiency in most climates allows it to deliver direct and indirect emissions reductions — a lower total equivalent warming impact (TEWI). For more than a decade, CO2 refrigeration has become a leading sustainability strategy for European retailers. Today, that trend continues with adoption steadily increasing in the U.S. and other countries.
Per recent industry data, nearly 46,500 CO2 transcritical booster systems are currently installed worldwide.
900 in the U.S. (1,400 in North America with the inclusion of Canada)
If CO2 growth trends continue as they have from 2020–2021, the U.S. commercial refrigeration industry can anticipate CO2 adoption to increase up to 50% by 2025. This trend is expected to follow a similar trajectory throughout the next decade, with the possibility that the U.S. could potentially mirror E.U. levels of adoption.
Regulations drive down GWP levels
Global, federal and state regulations are steering the industry away from HFCs and toward lower-GWP alternatives. Using the Kigali Amendment to the Montreal Protocol as a framework, the next step in the HFC production and consumption phasedown schedule will be a 40% reduction in 2024 (compared to the baseline established in 2011–2013).
The passing of the American Innovation and Manufacturing (AIM) Act in 2020 restored the Environmental Protection Agency’s (EPA) authority to enforce HFC mandates and establish sector-based guidelines. As the EPA follows the Kigali Amendment’s HFC phasedown, decreased supplies will continue to drive up HFC refrigerant prices.
The California Air Resources Board (CARB) continues its progressive efforts to phase down HFCs in the state of California. Under its recently adopted rule, all new refrigeration systems containing more than 50 pounds of refrigerant installed in new facilities must use refrigerants with less than 150 GWP. For existing installations with equipment greater than 50 pounds of refrigerant, retailers can take a fleet approach toward reducing their carbon footprint. CO2 refrigeration is becoming a leading option for achieving these regulatory targets.
Technological improvements and emerging applications
The proliferation of CO2 refrigeration systems around the globe has given equipment manufacturers opportunities to improve compression, controls and valve technologies. Emerson is at the forefront of efforts to simplify system management and help the industry transition from legacy high-GWP HFC systems.
Electronic system controllers
Emerson’s new Lumity™ E3 supervisory control for CO2 systems is designed to manage CO2’s high pressures and system volatilities, greatly simplifying commissioning and system management during standard operation. These improvements minimize system complexities, alleviate the burden from technicians, and provide peace of mind to end users.
Integrated CO2 transcritical booster system components
CO2 transcritical booster systems — where both medium- (MT) and low-temperature (LT) circuits run on R-744 — are the most widely adopted CO2 architectures in medium- to large-format food retail stores. Emerson is helping original equipment manufacturers (OEMs) and operators to ensure the system integration needed to maximize reliability and performance, including: compressors, electronic expansion valves (EEVs), high-pressure valves and an electronic controller.
Warm ambient strategies
CO2 transcritical booster systems are subject to declining efficiencies in warm ambient climates, but manufacturers have developed a variety of strategies to maintain efficiency levels.
Adiabatic gas coolers — keep the refrigerant below its critical point for as long as possible to maximize system efficiencies
Parallel compression — compresses excess flash gas at higher pressure via a dedicated intermediate- stage compressor, resulting in 8–10% annualized efficiency gains
Gas ejectors, liquid ejectors — optimize efficiency
Low superheat of MT evaporators — delivers year-round efficiency improvements
Increasing our commitment to CO2 innovation
Emerson is expanding CO2 labs, testing facilities and development capabilities to further CO2 adoption and support our OEM and end user partners. As the market for CO2 refrigeration continues to expand, the proliferation of new products is creating economies of scale, which lower the costs and complexities of implementing CO2 technologies. To learn more about improving the efficiency, usability and simplicity of CO2 systems, please visit our CO2 resources hub.
Emerson’s Commercial and Residential Solution’s Business
In the first blog in this series, we discussed the many distinguishing properties of CO2 (or refrigerant R-744) — including its high system pressures, low critical point and triple point. These characteristics introduce a multitude of unique servicing considerations that differ significantly from traditional hydrofluorocarbon (HFC)-based systems. In this installment, we’ll review some key tips that technicians need to be aware of when servicing CO2 transcritical booster systems. You can also learn more about a variety of related CO2 topics in our new CO2 Chats video series.
How do you store CO2 refrigerant?
From a refrigerant storage best practices perspective, R-744 tank storage is similar to standard HFC storage, including stacking procedures, safety precautions and keeping them chained off in a designated storage area. But that’s where the similarities end. Because CO2 tanks are designed to handle its high pressures, they weigh significantly more than standard HFC bottles. Empty CO2 tanks can weigh close to 150 lbs.; when loaded with 50 lbs. of refrigerant, each cylinder can potentially weigh nearly 200 lbs.
Many supermarkets prefer to have an entire system charge on hand, which could potentially be up to 2,000 lbs. Storing that would require 40 cylinders totaling a weight of 8,000 lbs. — or 4 tons. It’s important for contractors to understand where to store the reserve refrigerant and if it will affect building codes by having that much CO2 in one space. And if stored on a mezzanine, it must be capable of handling the total storage weight.
How do you charge a CO2 refrigeration system?
When charging a CO2 refrigeration system, the most important consideration a technician should keep in mind is the triple point pressure of CO2. 60.4 psi is the pressure at which CO2 will turn to dry ice. As a result, contractors must be careful not to charge with liquid CO2 when the system is below this pressure, and instead charge with vapor until the system reaches triple point. Failure to do so will result in the formation of dry ice. There are various anecdotes about technicians — who are more familiar with charging HFC systems — charging a CO2 system with liquid and causing the formation of dry ice.
Begin charging by introducing CO2 vapor into the system, and then build system pressure to 60.4 psi and beyond based on equipment manufacturer recommendations — up to 145 lbs. Then, it will be safe to switch to liquid CO2 to finish charging the system quickly and effectively without the risk of dry ice formation.
What is trapped liquid in a CO2 refrigeration system?
CO2’s coefficient of expansion (COE) is higher than a typical HFC refrigerant. One potential scenario that can occur in a CO2 system is when liquid refrigerant gets trapped in between two valves. In this instance, the pressure can increase 145 psi for every 1.8 °F increase in temperature. As a result, some systems may need to be fitted with appropriate pressure relief valves at the location of the trapped liquid to assist with system operation and service.
How do you detect leaks in CO2 systems?
Since there is an abundance of CO2 already present in the atmosphere, R-744 refrigerant can be difficult to detect and requires the use of a capable leak detection system. CO2 is colorless, odorless and heavier than air, requiring leak detectors to be mounted 18 inches off the ground and below the breathing level. Like HFC systems, it’s important to immediately detect and mitigate CO2 leaks as they occur.
Manufacturers such as Emerson have designed CO2-specific leak detection technology that quickly can sense the presence of higher levels of carbon dioxide in a machine room or a walk-in box. Emerson offers both a stand-alone CO2 leak detection solution as well as devices that can be seamlessly integrated into a building management system (BMS), such as the Lumity™ supervisory control platform.
Are there safety issues to be aware of when handling CO2 refrigerant?
Because CO2 refrigeration systems operate at extremely high pressures, technicians should take precautions when handling CO2. Even when the system is shut off, standstill pressures are extremely high and need to be handled carefully. In addition, CO2 can displace oxygen and release it in excessive amounts because it’s heavier than air. As a result, technicians should avoid handling it in confined spaces. But with proper training and equipment design, CO2 can be used safely.
For more information on CO2 servicing tips and best practices, please view the companion topic in our CO2 Chats video series. The next installment of the CO2 Refrigeration Fundamentals blog series will focus on system operation. To learn more about Emerson’s comprehensive CO2 products and capabilities, please visit Climate.Emerson.com/CO2Solutions.
Commercial & Residential Solutions is a global innovator of energy-efficient heating, air conditioning and refrigeration solutions for residential, industrial and commercial applications. www.climate.emerson.com
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