What the study found
Propane (R290) and carbon dioxide (R744) both showed promise as alternative refrigerants for electric vehicle thermal management systems. Propane delivered comparable efficiency to the current baseline refrigerant, R1234yf, while having a much lower global warming potential, but its flammability creates integration challenges.
Why the authors say this matters
The authors say the anticipated PFAS ban in the US by 2029 creates a need to evaluate alternative refrigerant solutions. They conclude that propane could be a feasible replacement for electric vehicle applications if safety measures are implemented, and that carbon dioxide remains a strong candidate as a cost-effective and PFAS-compliant solution.
What the researchers tested
The researchers compared three refrigerant candidates—propane (R290), carbon dioxide (R744), and R1234yf—through system-level testing and demonstration projects. They also described mitigation measures for propane safety, including rapid leak detection, robust containment strategies, and optimized circuit layouts, which were validated in the European Commission’s QUIET project.
What worked and what didn't
R1234yf served as the current industry baseline. Propane achieved comparable efficiency and, in a Honda B-segment electric vehicle setup, a propane-based heat pump combined with thermal storage, infrared cabin heating, and lightweight materials was reported to increase driving range by 25% in cold conditions while maintaining passenger comfort. CO₂ also demonstrated promising performance.
What to keep in mind
The abstract notes that propane’s flammability presents integration challenges that are not present with R1234yf or R744. The study also does not provide detailed limitations beyond the safety concerns and the specific demonstration context described in the summary.
Key points
- Propane (R290) showed comparable efficiency to R1234yf and a much lower global warming potential.
- Carbon dioxide (R744) also demonstrated promising performance as an alternative refrigerant.
- Propane’s flammability was identified as a safety and integration challenge.
- Safety countermeasures for propane included leak detection, containment strategies, and optimized circuit layouts.
- In a QUIET project demonstration, a propane-based setup in a Honda B-segment EV was reported to increase cold-weather driving range by 25% while maintaining passenger comfort.
Disclosure
- Research title:
- Propane and carbon dioxide show promise as EV refrigerants
- Publication date:
- 2026-04-07
- OpenAlex record:
- View
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