Which of the following refrigerants has a GWP closest to 1?

• A. R-134A
• B. R-410A
• C. R-123
• D. R-32

Answer: (B)

The correct answer reflects the understanding of Global Warming Potential (GWP) in relation to the refrigerants listed. GWP is a measure of how much heat a greenhouse gas traps in the atmosphere over a specific timeframe, relative to carbon dioxide, which is assigned a GWP of 1.

R-32 has a GWP of approximately 675, making it significantly lower than many commonly used refrigerants, yet it is not close to 1. R-134A has a GWP of about 1,430. R-410A has an even higher GWP, around 2,088, signifying a larger environmental impact relative to CO2.

R-123 is a refrigerant with a GWP of approximately 79, which is lower than R-32, but still not close to 1.

In contrast, the refrigerant closest to a GWP of 1 among those listed is R-123, making it the most suitable choice when evaluating the GWP in context to carbon dioxide as a baseline. This understanding is crucial for selecting refrigerants in a way that minimizes environmental impact, particularly relating to greenhouse gas emissions.