Wednesday, November 30, 2011

New Reefer Technology Cuts Emissions For Freight Containers

Innovative Product Makes Its Debut At Hamburg Show
Shipping News Feature

GERMANY – WORLDWIDE – In January we featured advances in freight container refrigeration systems using the natural refrigerant CO2. The system underwent testing by by German shipping line Hapag Lloyd and, appropriately enough, the German port of Hamburg was the backdrop this week as the new Carrier Transicold product made its debut at the Intermodal Europe Show. By using CO2 as a natural refrigerant in reefer boxes, the Carrier Transicold NaturaLINE design improves upon the company’s best in class performer PrimeLINE unit’s ability to reduce carbon dioxide emissions by a further 28% percent compared to previous units. David Appel, president, Carrier Transicold said:

“Advancing Carrier’s leadership in environmental technologies for the marine container refrigeration market, the new design provides the global shipping industry with the most environmentally sound alternative for refrigerated transport. NaturaLINE stands apart as the only one to offer a natural refrigerant-based solution.”

NaturaLINE uses two stages of compression, which improves the overall efficiency of the unit. Its unique cylinder unloading capability allows the compressor to save energy in light-load conditions. The variable-speed drive that controls the compressor is a first for a Carrier container refrigeration unit. The custom designed drive electronically adjusts the compressor’s speed to provide the precise amount of cooling capacity to meet demand, saving considerable energy compared to conventional units. The inbuilt technology replaces the condenser assembly found in conventional refrigeration units with a new heat exchanger called the gas cooler. The gas cooler coil wraps around the fan, maximizing heat-transfer surface area for greater efficiency in a design that is both compact and lightweight. Mike Griffin, Carrier Transicold’s new product development program manager commented:

“Addressing the special thermodynamic properties of CO2 necessitated the development of an innovative refrigerant management system, including a new purpose-built, multi-stage compressor with variable-speed drive, a ‘gas cooler’ with a wrap-around design and a flash tank. The patented reciprocating multi-stage compressor maximizes capacity and minimizes power consumption. The gas cooler makes the overall refrigeration system more versatile in responding to the thermodynamic properties of CO2, providing gas cooling after each compression stage for better efficiency.”

The flash tank, an entirely new component in a container refrigeration system, is designed to manage the flow and phase change of the refrigerant after leaving the gas cooler. For efficient cooling performance, the patented Carrier design enables final separation of CO2 from its gas phase to the liquid state before entering the evaporator. The basic frame, the evaporator and evaporator fans, and the controller and control box are virtually identical to existing Carrier Transicold models. The easy-to-use control interface works the same as on other container refrigeration units. Also, serviceability will be similar to existing Carrier Transicold products, and will be supported by a new comprehensive training program.