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Posts from the ‘Food Quality & Safety’ Category

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.

 

Montreal Protocol Members Declare Commitment to Reduce Food Loss and Waste

RajanRajendran2 Rajan Rajendran | V.P., System Innovation Center and Sustainability

Emerson Commercial & Residential Solutions

In November, the 31st Meeting of the Parties to the Montreal Protocol convened in Rome to discuss progress in their ongoing efforts to protect the Earth against ozone depletion and global warming. Among the new topics introduced by member nations was the need to implement sustainable and efficient solutions in the refrigeration and air-conditioning sector — not only to meet future cooling demand but also to include cold chain initiatives for food preservation.

Montreal Protocol Members Declare Commitment to Reduce Food Loss and Waste

For more than three decades, the Montreal Protocol has introduced measures to reduce the harmful environmental impacts of cooling technologies — first with a mandate to phase out ozone-depleting substances such as chlorofluorocarbons (CFCs), and most recently with the Kigali Amendment, which targets a phase-down of hydrofluorocarbons (HFCs). As these efforts have experienced wide adoption by its global member nations, the Montreal Protocol’s stakeholders are now vowing to take a closer look at additional cooling-related climate issues, such as reducing food waste and creating a more sustainable cold chain.

At the November meeting, key stakeholders discussed the Montreal Protocol’s global responsibilities to continue its leadership in climate matters and extend its efforts into reducing global food loss and waste. Participants stressed the urgency for countries to work together to find new solutions to address world hunger — noting that it would be possible to feed the entire world with current food production levels if waste was eliminated.

Participants also discussed other far-reaching benefits of these efforts toward creating more sustainable cold chains, such as: price stabilization; improved food security; enhanced profitability; more secure livelihoods; social and economic development gains; fair and just sustainability transitions; achieving sustainable development goals; continuing research, development and innovation; synergistic action; and restoration of degraded lands.

Introducing the Rome Declaration

At the November Meeting of the Parties to the Montreal Protocol, members were invited to support the Rome Declaration on the Contribution of the Montreal Protocol to Food Loss Reduction through Sustainable Cold Chain Management initiative. Currently, the Rome Declaration has been signed by ministers of 76 countries and is open for additional member signatures until the start of the next Meeting of the Parties, to be held next November.

The Rome Declaration calls for both national action and international cooperation to promote sustainable cold chain development, including the use of environmentally friendly refrigeration to reduce food loss. It states that achieving its objectives will require cooperation among governments, the Protocol’s institutions, United Nations (UN) specialized agencies, existing private and public initiatives, and all relevant stakeholders to exchange knowledge and promote innovation.

Among the Rome Declaration’s key objectives is to provide access to energy-efficient, sustainable refrigeration technologies in developing nations — particularly those that follow the Montreal Protocol’s guidance on refrigerants — thereby helping them contribute to the reduction of food loss and waste.

Aligning with Emerson’s cold chain capabilities

We won’t know for some time whether the Rome Declaration will become an internationally agreed upon mandate. But like the previous efforts of the Montreal Protocol to phase down harmful substances used in cooling devices, the Rome Declaration is an opportunity to leverage Emerson’s efforts in providing sustainable and energy-efficient solutions — not only in the refrigeration and air-conditioning sectors, but throughout the global cold chain.

From compressors and refrigeration system technologies to temperature monitoring and tracking devices to connected electronic controllers and facility management systems, we’re committed to helping cold chain stakeholders achieve temperature certainty and maximize energy efficiencies in the most environmentally responsible means possible.

 

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