Latest Generation of Fans Boost Efficiency of CO2 Refrigeration

Fans and their components are often overlooked or taken for granted in refrigeration systems. Yet they can have a considerable impact on overall efficiency and carbon footprint.

For example, the latest generation of electronically commutated (EC) fan motors – brushless DC motors with integrated AC-to-DC conversion – can improve the efficiency of CO2 (R744) refrigeration systems in "several ways," according to David Bolaños, Head of Product Management at Heatcraft Refrigeration Products, a U.S.-based manufacturer of refrigeration equipment.

"[EC fan motors] are designed to be highly energy-efficient and use less electricity to achieve the same level of performance as traditional fan motors," he said. "As the overall system's energy consumption is reduced, this in turn reduces the overall greenhouse gas emissions associated with electricity generation."

"[EC fan motors] are designed to be highly energy-efficient and use less electricity to achieve the same level of performance as traditional fan motors."

Bolaños noted that EC technology can also help to reduce operators’ environmental footprint due to the improved reliability it can offer.

"It can reduce the need for maintenance and repairs and help extend the lifespan of the refrigeration system," he added. "In turn, this reduces the environmental impact associated with disposing of components and/or systems."

By using advanced control algorithms to adjust the speed of the motor to match the system's load requirements, EC technology – like other variable speed technologies – can significantly reduce energy consumption, Bolaños explained.

This also enables the compressor motor to run at lower speeds during periods of low demand, which in turn reduces wear and tear on the compressor, he added.

"Given [EC motors’] capability to match heat loads and run at lower speeds, they can help to reduce noise levels, improve system reliability and provide more precise control over the refrigeration process," he said.

According to Lou Moffa, Market Manager at ebm-papst, a German fan manufacturer, EC fans have been on the European and U.S. markets for over a decade.

ebm-papst offers a range of efficient EC fan motors, including its iQ-one for refrigerated display cabinets and shelves in supermarkets and its AxiEco axial fans for heat pumps.

While there are a range of options for CO2 applications, EC fans are the easiest and best choice, Moffa said.

"Our fans are a complete assembly consisting of an EC motor, balanced blades, finger guard and wall ring, all of which are optimized to work together for best overall air and electrical efficiency," he explained.

ebm-papst's EC motors have built-in protection to prevent costly operational failures, he added. If a fault is detected with the fan, this functionality stops operation and only restarts once the fault has been eliminated. While motor-protection devices can be added to a fan, this also adds cost and complexity to the system.

ebm-papst fans include built-in, two-way Modbus communication, which enables control and monitoring of the fans and can be used for preventative maintenance. Another feature is a built-in soft start to prevent high electrical loads on start-up, which results in quieter overall operation and reduced shock to the assembly, he said.

With the goal of strengthening its presence in different key markets, ebm-papst has been expanding its manufacturing capacity in the U.S. with a new plant in Telford, Tennessee, and in China with its new local headquarters in Shanghai. In addition to its administrative departments, the new development in China will also include a production plant and two warehouses.

The manufacturer has also recently announced that it will be expanding its product portfolio to include turbo compressors, which will be used in heat pumps and other applications. Series production for the new products is planned to start in 2026.