Next Generation Refrigerant
Daikin’s next gen refrigerant, R-474A, with a GWP<1 is specifically designed for electric vehicles (EV) and delivers increased cooling and heating capacity with superior efficiency.
Industry Trends
Low-GWP refrigerants play a crucial role in securing the long-term sustainability of the A/C industry and modern society as a whole. Daikin is actively engaged in this effort and has developed a next generation of Ultralow GWP refrigerants for all manufacturers and industries, including automotive. Electric Vehicles (EV)s equipped with heat pumps differentiate automotive OEM’s as they provide the added benefits of both increased passenger comfort and battery performance.
The Challenge
- Electric vehicles lose 7-20% of their rated driving range in cold weather conditions due to the energy consumption necessary to heat the passenger cabin and for conditioning the battery.
- The performance of the current MAC fluids, R134a & R1234yf, at low temperatures is extremely limited by their low pressure and low capacity. A supplementary electric heater or complex systems become necessary, compromising the value of the heat pumps using those refrigerants.
The market need for a new refrigerant:
- Environmental Impact: GWP <1 to meet US AIM and EU F-Gas global warming reduction goals
- Safety: Comparable to 1234yf, Suitable for use in the cabin
- Performance:
- Pressure suitable for direct expansion system in wide temperature range
- Higher capacity and the ability to heat the passenger and battery at ambient temperature of -30°C (-22°F)
Daikin’s Unique Molecule
- Daikin has developed a new and unique molecule, HFO-1132(E), with a GWP of <.004
- Physical Properties Close To R32, an Ideal Component For A2L Blends.
- The First And Only Medium Pressure HFO To Be Commercialized and ASHRAE Listed
| HFO-1132(E) | ||
| Molecular formula | CHF=CHF | |
| Molecular weight | g/mol | 64.0 |
| Critical temperature | ℃ | 75.7 1) |
| Critical pressure | MPa | 5.17 1) |
| Boiling point (101.3kPa) | ℃ | -52.5 1) |
| Vapor pressure at 25 ℃ | kPa | 1,666 1) |
| Vapor density at 25℃ | kg/m3 | 56.4 |
| Liquid density at 25℃ | kg/m3 | 938 |
| Latent heat at 25℃ | kJ/kg | 213.7 |
| Lower flammability limit | vol% | 4.4 |
| Burning velocity | cm/s | 32.9 |
| GWP | 0.0036 2) |
Features Of R-474A
Ultra-low GWP A2L Refrigerant Capable Of Maintaining Positive Pressure Even Under Very Low Ambient Air Temperature Conditions.
- Environmental Impact: GWP <1
- Safety: Mildly flammable, comparable to R1234yf
- +40% additional heating and cooling capacity compared to current solutions
- Ability to heat at ambient temperature down to -30℃
- Matching efficiency (COP) to R1234yf across all temperatures
- Manageable temperature glide (4K)
|
|
Existing automotive refrigerants |
New refrigerant |
|
|
R134a |
R1234yf |
R-474A |
|
|
Composition |
– |
– |
HFO-1132 ( E ) / R1234yf |
|
Boiling point (101.3 kPa) |
-26.1 °C |
-29.4 °C |
-44.6 °C |
|
Critical Temperature |
101.1 °C |
94.7 °C |
87.1 °C |
|
Critical Pressure |
4.06 MPa |
3.38 MPa |
4.04 MPa |
|
Pressure (25°C) |
0.67 MPa |
0.68 MPa |
1.07 MPa |
|
ODP |
0 |
0 |
0 |
|
GWP AR5 |
1300 |
< 1 |
< 1 |
|
LFL (vol % in air) |
– |
6.2 |
5.5 |
|
Burning velocity |
– |
1.5 cm/s |
2.9 cm/s |
|
ASHRAE Safety Class |
A1 |
A2L |
A2L |
Performance
- D1V Range provides best in class cooling and heating performance.
- Charge reduction can contribute to further cost benefits
- GWP<1 to provide a sustainable technology for MAC
- Significant work complete on system performance, safety assessments, and material compatibility which indicates a near drop-in solution with respect to the current R1234yf systems and industry standards
- Multiple Tier 1 and OEM evaluations complete through the SAE-CRP Project.
