Case studies on alternatives to HFCs

Chile launches demonstration of alternative refrigeration technology
Closed
started:
2014

The Coalition's HFC initiative promotes HFC alternative technologies and standards to significantly reduce the projected growth in the use and emissions of high-global warming potential (GWP) HFCs in coming decades relative to business-as-usual scenarios.

The HFC Initiative is helping achieve this by improving understanding of current and projected future use of HFCs, by sharing lessons learned on the design and implementation of policies to reduce their emissions and use, by addressing barriers, including reforming standards, and by validating climate-friendly technologies in key areas of HFC use or projected growth.

As countries phase out hydrochlorofluorocarbons (HCFCs) and phase down hydrofluorocarbons (HFCs) under the Montreal Protocol on Substances that Deplete the Ozone Layer, they often need to make choices between high-GWP alternatives and, when available, more climate-friendly alternatives. Depending on the alternatives selected, the increase in HFC emissions could partly offset the climate benefits achieved by the earlier reduction in ozone-depleting substance (ODS) emissions under the Montreal Protocol.

In order to assist in planning and implementing ODS transitions that minimise climate impacts, the Coalition has collected case studies on low-GWP energy-efficient technologies that have been adopted in the commercial refrigeration sector as alternatives to replace or avoid high-GWP HFCs. Given that the commercial refrigeration sector has a number of climate-friendly refrigerant alternatives that are already commercialised or near commercialisation in some countries and regions, the reports present lessons learned from real cases in commercial refrigeration and aims to stimulate further investigation to enable a smooth transition away from high-GWP refrigerants and assist in the selection of future refrigerants.

Background

The commercial refrigeration sector comprises the equipment, technologies and services used to store and dispense frozen and fresh foods at the appropriate temperatures. This sector includes stand-alone or self-contained systems, condensing unit systems, and centralised or ‘multiplex rack’ systems. According to the 2010 assessment of the Montreal Protocol advisory panel, the Technology and Economic Assessment Panel (TEAP) Technical Option Committee, these categories were estimated to contribute 7%, 47%, and 46% respectively to the total quantity (or ‘refrigerant bank’) of refrigerant used in 2006.

The special report of the Intergovernmental Panel on Climate Change (IPCC)/TEAP indicated that on a global basis, commercial refrigeration is the refrigeration subsector with the largest CO2-equivalent emissions, representing 40% of total annual refrigerant emissions. These emissions are categorised as direct and indirect emissions. Direct emissions refer to emissions of the refrigerant itself during system manufacturing, operation, and disposal at end-of-life. Indirect emissions refer to the emission of carbon dioxide and other greenhouse gases (GHGs) that result from the energy consumption (usually electricity) of the system over its lifetime.

Reducing leakage rates through better design and installation practices will reduce direct emissions. As reported by the IPCC, the refrigerant emissions might represent 60% of the total emissions of GHGs resulting from system operation, the rest being indirect emissions generated by power production. A higher Coefficient of Performance (COP = heat removed/ required work) for the refrigerated system will help in reducing the indirect emissions since the amount of work required to remove the heat will decrease.

Meanwhile, the transport refrigeration sector comprises the equipment, technologies and services used to transport and dispense frozen and fresh foods at the appropriate temperatures. Travel time, ambient temperatures, and risk of spoilage often make temperature controlled transportation necessary. Because some commodities are sensitive to the relative humidity and chemical composition of their surrounding atmosphere, these conditions may also need to be controlled. Today many commodities travel to distant markets intermodally (i.e., by some combination of highway, ocean and railroad).

Objectives

The case studies were developed with the intention to assist governments in planning and implementing transitions from HCFCs and HFCs that minimise climate impacts. They provide examples of low-GWP energy-efficient technologies in the commercial refrigeration and transport refrigeration sectors.

The Coalition, through the UN Environment OzonAction, collected case studies that offer information for system purchasers and operators to consider when upgrading or replacing existing equipment with newly designed systems that decrease impacts on the ozone layer and climate change. Even though the majority of cases are from industrialised (Non-Article 5) countries, the information and experiences presented are relevant to all countries to help users, technical managers, consultants, engineers, designers and equipment suppliers in their assessments and understanding of these technologies in order to achieve similar success. The issues discussed in the case studies are primarily related to transitioning to climate-friendly refrigerants and also include innovative technologies, methodologies and concepts which enhances the overall sustainability of commercial and transport refrigeration systems. These examples from end-users can help build confidence in, and illuminate pathways toward, more climate-friendly commercial and transport refrigeration.

Commercial Refrigeration

Research was conducted to generate a list of potential case studies for consideration taking into account all of the currently available zero- and lower-GWP refrigerants in commercial refrigeration applications, including “natural” or non-fluorinated refrigerants, such as hydrocarbons, carbon dioxide (CO2), ammonia, and R-290 (propane) as well as the other major category of alternatives comprising man-made chemicals such as the unsaturated HFCs known as hydrofluoroolefins (HFOs) which include R-450A and R-449A. HFOs are a new class of unsaturated HFC refrigerants which have shorter atmospheric lifetimes and lower GWPs when compared to other HFCs. Some criteria such as geographic location, refrigerant used and available information of the proposed applications were taken into consideration when selecting the case studies. These chosen case studies examine energy efficiency benefits of alternatives, as well as cost, safety, availability, maintainability, life expectancy and other sustainable and environmental considerations.

Robust technical information was collected in the chosen case studies based on data provided by the source. These case studies also provide a detailed analysis for the system components, methodologies, and controls technology to optimise energy efficiency and continually update with new developments. An overview of the refrigeration cycles that are used in supermarkets is provided below.

Transport Refrigeration

To compile the case studies, research was conducted to generate a list of potential case studies for consideration taking into account all of the currently available zero- and lower-GWP refrigerants in transportation refrigeration applications. Some criteria such as geographic location, refrigerant used and available information of the proposed applications were taken into consideration when selecting the case studies. However obtaining appropriate and relevant case studies in the transportation refrigeration sector was something of a challenge. Included below are three case studies with CO2 and LN2 refrigerants with innovative technologies and systems in the field of transportation refrigeration. The intention is in the future to collate further case studies from other transportation sectors as well as examples of other lower-GWP refrigerants and advanced technological inventions, systems and strategies. These chosen case studies take into account energy efficiency benefits of alternatives, as well as cost, safety, availability, maintainability, life expectancy and other sustainable and environmental considerations. Robust technical information was collected in the chosen case studies based on data provided by the source. These case studies also provide a detailed analysis for the system components, methodologies, and controls technology to optimise energy efficiency and continually update with new developments. The technologies presented in these case studies are only some examples of the many available options for zero- and lower-GWP substances, taking into account all design criteria, such as system performance, environmental impact, and cost analysis. The cases presented here focus on CO2, and LN2 refrigerants.

All these refrigerants still have many challenges that should be considered in the design such as their flammability, toxicity, lower efficiencies in some cases, and cost. Balancing the safety, energy efficiency, cost, and environmental impact of refrigerants using a consistent and comprehensive methodology across all refrigerants and system types is essential in assessing alternatives. Good design is also important for reducing refrigerant emissions and preventing refrigerant loss during installation, operation and maintenance, decommissioning and end-of-life disposal.

Who's involved

Lead Partner: A Coalition partner with an active role in coordinating, monitoring and guiding the work of an initiative.

Implementer: A Coalition partner or actor receiving Coalition funds to implement an activity or initiative.

Partners (3)

Partners (3)

Implementer

Resources & tools

Activity contact

Denise San Valentin,
Initiative Coordinator
Denise.Sioson [at] un.org

Initiatives

Pollutants (SLCP)

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