The power-recovery turbine design for a vapor-compression refrigeration cycle is the best to be more energy-efficient compared to a standard design, as it recovers some of the energy during expansion.
The report is titled: Evaluation of Vapor-Compression Refrigeration Systems for Industrial Refrigerator
The Objective: To evaluate two alternative vapor-compression refrigeration systems for an industrial refrigerator and recommend the most cost-effective option.
The Analysis that was done:
1. Standard Vapor-Compression Refrigeration Cycle: Ammonia is the most efficient refrigerant based on COP. However, ammonia's toxicity and flammability pose safety concerns.
2. Vapor-Compression Refrigeration Cycle with Power-Recovery Turbine: Ammonia remains the most efficient refrigerant based on net power input and COP.
So, my Recommendation is the Vapor-compression refrigeration cycle with power-recovery turbine and ammonia as the refrigerant is the most cost-effective option based on electricity cost.