Which property is desirable to maximize energy storage during the refrigerant’s phase change?

• A. High latent heat
• B. Low latent heat
• C. High vapor pressure at ambient
• D. Low boiling point

Answer: (A)

Energy storage during a refrigerant’s phase change hinges on latent heat—the amount of heat absorbed or released as the substance changes phase at a constant temperature. To maximize how much energy can be stored per unit mass, you want a refrigerant with a high latent heat of the phase change, so more heat is transferred during evaporation or condensation without raising the temperature. The other properties affect how the system operates rather than how much energy is stored per kilogram: high vapor pressure at ambient influences pressure and hardware design, not the storage capacity; a low boiling point sets the operating temperature range but doesn’t increase the energy stored per mass. So, high latent heat directly boosts the energy storage capability during the phase change.