Development and Testing of an Energy Efficient Ultra-low Charge Ammonia Refrigeration System in a Food Processing Plant

The project is demonstrating an energy efficient chiller system using a low global warming potential refrigerant at a food processing facility.

Electric Power Research Institute, Inc.


Palo Alto, CA

Recipient Location


Senate District


Assembly District



Amount Spent



Project Status

Project Result

Project is complete and the low-charge, packaged ammonia chiller installation is operating normally as confirmed by monitoring and verification (M&V) data. Results show that the ammonia chiller is 38 % more efficient than the R-507A chiller. The project team is now receiving monthly water treatment reports to track the change in the cycles of concentration for the R507A cooling tower. This allows monitoring of the amount of water consumed each month (gallons/month) and the number of gallons used per kWh of cooling provided.

The Issue

Most ammonia-based cooling systems in use today require large amounts of ammonia and are prone to leakage from the mechanical shaft seal between the motor and compressor, and require special handling. Additionally, most ammonia systems used today are either water cooled or evaporative cooled, which require water, a very limited and precious resource in California due to recent droughts.

Project Innovation

This project is pilot testing and demonstrating an air-cooled, low-charge ammonia refrigerant-based, integrated package closed cooling system for an industrial food processing application. The project is demonstrating the effectiveness of a water-saving innovation with the use of a micro-channel, air-cooled condenser. The project is demonstrating the expected energy savings of 20% compared to a chiller using hydrofluorocarbon (HFC) refrigerant for similar end use at the same site. This system eliminates the need for water for cooling. The entire system can be prepackaged, factory charged, and brought to site as an integrated package which simplifies field installation and makes it cost effective.

Project Benefits

An air cooled, low-charge, ammonia refrigerant based integrated closed-packaged system with semi-hermetic motor/compressor seal that eliminates the mechanical seal between the compressor and the motor is not available in the U.S market today. As this is a packaged product, the M&V data from this project will help verify the energy savings and benefits and make it easier for industries to understand and implement this new technology and the energy and water savings benefits.

Lower Costs


Expected energy savings of at least 20% compared to a chiller using hydrofluorocarbon (HFC) refrigerant for similar end use at the same site. This system eliminates the need for water for cooling, which further adds to on-site cost savings.

Key Project Members

Project Member

Ammi Amarnath

Senior Technical Executive



Mayekawa USA, Inc.


Match Partners


Electric Power Research Institute, Inc.




Contact the Team