Which change would lead to an increase in system efficiency?

A reduction in specific volume at the compressor inlet leads to an increase in system efficiency because it allows for a higher mass flow rate of the refrigerant entering the compressor. When the specific volume is reduced, the refrigerant becomes denser, meaning that for the same volume of gas, more mass is present. As a result, the compressor can do more useful work with the same energy input, which enhances the overall efficiency of the refrigeration or air conditioning system.

Additionally, improving the efficiency of the system correlates directly with better performance and lower energy consumption, making it more effective in transferring heat from one area to another. When less energy is required for compression, operating costs can decrease, and the system can achieve a higher coefficient of performance (COP), making it an economically and environmentally favorable option.

In contrast, increasing specific volume would result in the compressor working less efficiently, as it would have to compress a larger volume of refrigerant, while lowering refrigerant temperature alone does not necessarily enhance efficiency if it leads to other issues like reduced pressure or changes in phase. Using a smaller compressor can also hinder performance if it cannot handle the required load effectively, leading to increased run times and potentially greater wear over time.