Key Considerations for Refrigerant Choice

Each application has different characteristics, so there is no one-size-fits-all solution. It is necessary to focus on selecting the appropriate refrigerants for each application based on an overall assessment. In this overall assessment, Daikin believes it is necessary to assess four basic factors comprehensively: safety, environmental impact, energy efficiency and cost-effectiveness.

Daikin's View: Action on Refrigerant and Goals Evaluation Index of Refrigerant Selection (common for all application)

Safety

A refrigerant must be safe to use through the entire lifecycle of the equipment. This includes transport, storage, installation, use, servicing, recovery and recycling.

This means that possible hazards such as toxicity or flammability characteristics, as well as the risk of human error, must be evaluated for each type of application. While non-flammable and low-toxicity refrigerants may have safety benefits, they may not be ideal from an environmental point of view.

In addition, some refrigerants may be acceptably safe for one type of equipment but not sufficiently safe for others. Thorough risk assessments are therefore needed for each application.

Environmental Impact

A core consideration in refrigerant choice is its environmental impact. This impact includes a refrigerant's ozone depleting potential (ODP*¹) and its potential global warming impact: this is expressed as its CO₂ equivalent, which is the refrigerant quantity multiplied with its global warming potential (GWP*²).

Heat transfer capacity and heat exchange efficiency of refrigerants are also important characteristics that result in reductions in refrigerant quantity and allow more compact equipment design. Environmental considerations also include the impact of the refrigerant production process and a refrigerant's potential to be recycled and reused.

*1 ODP:

“Ozone-depleting potential” – A value indicating the intensity of ozone layer destruction by various substances based on the ODP of CFC-11 as a standard.

*2 GWP:

“Global warming potential” – A value indicating the degree of contribution to global warming of various GHGs based on CO₂ as a standard. (Example: R-410A: 2,090, R-32: 675)

Energy Efficiency

Daikin carefully considers a refrigerant's potential to improve the energy efficiency of its equipment in both cooling and heating functions across an extreme range of climate conditions including very hot and very cold environments. This is an important consideration as energy consumption for cooling, heating and refrigeration has a substantial impact on the total energy consumption of buildings and countries.

Depending on how electricity is generated in each country, its efficient use also has a large indirect impact on climate change by reducing CO₂ emissions. Therefore, energy efficiency is critical in choosing the right refrigerant for a given application.

Cost-Effectiveness

It is important to provide consumers access to affordable solutions for their homes and businesses. In addition, in order to reduce the environmental impact, cost-effectiveness should be considered in terms of dissemination. For instance, is the refrigerant easy and inexpensive to install and maintain? Does the refrigerant allow for compact cost-efficient designs to minimize investment costs? Does a refrigerant contribute to reducing overall system operation and maintenance costs? Is recycling of the refrigerant feasible and cost-effective? Would possible risk mitigation measures be cost-effective? These are factors to consider when selecting cost-effective refrigerants.