The HVACR industry is always exploring new options that may lead to more efficient, cost-effective, and environmentally friendly refrigerants to keep facilities — and the people and technology in them — comfortably cool.
Recent headlines have highlighted and escalated the ongoing efforts to curb greenhouse gas emissions from automotive exhaust, mobile air conditioning, commercial refrigeration refrigerant leaks, and other contributors to greenhouse gas emissions.
Industry, manufacturers, and governments are seeking alternative refrigerants that have lower global warming potential (GWP) than the widely accepted hydrofluorocarbon (HFC) refrigerants of today. Since 1987, the Montreal Protocol and other multinational treaties have focused efforts on pragmatic changes to address real concerns for the environment with social and economic needs in both developed and developing countries.
It’s clear that someday, equipment using HFCs will need alternative fluids. The refrigerant industry is undergoing an intense research and development phase to identify the next best alternatives and has come up with a few promising options. However, today, when we look at what has the potential for commercial viability, there are many challenges for some of these fluids to emerge as the HVACR industry’s next-generation refrigerants of choice. Let’s look at some of the challenges each faces to help understand how this transition will take place.
Owners, service companies, manufacturers, and retail outlets have significant concerns over availability. In one case, most of today’s supply is now sold to the foam-blowing industry for the production of building insulation. While new plants are being built to produce the refrigerant, it will be at least 2017 before this liquid is expected to be widely available for new equipment, and potentially longer until it is readily available in local retail outlets for service technicians.
With the current low production volume, these alternative refrigerants can cost three to five times more than today’s HFCs. And, even as production ramps up, the chemical nature of these new refrigerants will likely continue to make them more expensive than today’s HFCs well into the future.
Some equipment manufacturers are looking only at how these refrigerants will work with one component of a system they produce. More importantly, the industry needs to know how they will work with an overall system as used by customers on a daily basis. Certain new low-GWP refrigerants have the effect of lowering the efficiency of HVACR equipment in specific applications.
Some of these alternative refrigerants fall into new flammability classes. Codes and standards, such as ASHRAE 15 and ISO 5149, are being revised to acknowledge the new class of flammability; however, it will take time for the new revision to be incorporated in building codes and then for the revised building codes to be adopted by local jurisdictions.
Many of the new alternatives present challenges to manufacturers, owners, operators, and service personnel with special handling and transportation requirements for flammable refrigerants.
Technicians must be trained to service what amounts to a new technology. Also, current HVACR equipment will have to be modified to use these refrigerants. Industry customers will pay those costs, however steep they are.
It may take as long as five to 10 years to work through these issues. And these are issues that need to be addressed by industry experts. This is not something customers should be asked to handle.
Understandably, everyone wants to quickly get improved, low-GWP refrigerants on the market. But that cannot be done in a way that damages the environment and current chiller equipment, causes safety issues, or is virtually unaffordable.
Industry customers like the idea of using low-GWP refrigerants based on their desire to lower carbon emissions from their businesses. But, it’s important to remember the vast majority of greenhouse gases released into the atmosphere result from the burning of fossil fuels. As much as 98 percent of the total GWP impact of HVACR equipment comes from the indirect emissions from electricity use and the production and disposal of the units and related equipment.
A prime HVACR industry goal should be making the systems that cool our buildings as efficiently as possible. Since the 1980s, we have made improvements outside of refrigerants that have increased average chiller efficiency by at least 40 percent. These improvements are the result of improved aerodynamic designs, new heat exchangers, optimized controls, and new bearing technology. Variable-speed drives (VSDs) are another energy-efficiency innovation, and their use has been growing throughout the last 35 years.
Some of the alternative refrigerants have been shown to lower equipment efficiency. The Air-Conditioning, Heating, and Refrigeration Institute’s (AHRI) Low-GWP Alternative Refrigerants Evaluation Program (Low-GWP AREP) has tested many low-GWP fluids. In some ways, they outperformed other available refrigerants, while in other ways, they didn’t measure favorably. If a low-GWP liquid isn’t at least as efficient as what it replaces, then the industry would be moving backwards, and causing more damage to the environment than good.
Choosing a refrigerant shouldn’t be made on any one factor, especially a lower GWP. There is no single refrigerant solution for every need. Each application needs to be evaluated on factors including use, location, size, local regulations, and the type of equipment being employed. Maintaining HVACR equipment is equally important, since refrigerant only has an impact on carbon emissions if it leaks or is mistakenly released into the atmosphere. Simply put, it’s important to select the right refrigerant for the right building and the right equipment.
Customers count on our industry to provide them with information on refrigerant safety, reliability, performance, efficiency, and costs in order to make informed decisions.
The truth is, the best overall refrigerants are already widely available on the market today. This means that right now, there are excellent choices that benefit customers with high efficiency and low carbon emissions at a practical cost. As an industry, we must remain involved in the ongoing development of new refrigerants while always looking to protect the best interests of our customers and the environment.
Bill McQuade is director of technology, energy efficiency, and the environment for Milwaukee-based Johnson Controls Inc. For more information, visit www.johnsoncontrols.com.
Publication date: 10/20/2014