Among the multiple tiers of emissions standards issued by the U.S. Environmental Protection Agency (EPA), it’s the comprehensive Tier 4 emissions standards that have impacted the development of refrigeration units and led to the integration of engine and fuel controls.
Also affecting refrigeration unit design is the California Air Resources Board (CARB) Airborne Toxic Control Measure (ATCM) for In-Use Diesel-Fueled Transport Refrigeration Units and TRU Generator Sets, and Facilities Where TRUs Operate. The TRU ATCM mandates a phased approach to reduce diesel particulate matter emissions from in-use TRU engines that operate in California.
The CARB In-Use Performance Standards set requirements by horsepower range, which can be achieved by using an engine that meets the required engine certification value, retrofitting the engine with the required level of verified diesel emissions controls, or using an alternative technology.
As a result of these environmental legislative efforts, manufacturers are now producing new refrigeration unit technologies. Those designs also help lower costs for users by cutting fuel consumption and maintenance requirements.
Designed for stationary cold-storage applications, Carrier Transicold’s new engineless Vector 8100 all-electric trailer refrigeration unit operates on electric standby only. The 8100 unit is designed especially for supermarkets, produce warehouses, food distribution centers and other businesses that use refrigerated trailers for on-site cold storage.
The 8100 joins Carrier’s Vector product line, which also includes 8500 single-temperature and 8600MT multi-temperature models designed for over-the-road transport and which are capable of being plugged into an electric power source. Both models are diesel-electric hybrids and both have a diesel engine that drives an electric generator, which provides power for the refrigeration system when on the highway.
The Vector 8500 and 8600MT models are in compliance with EPA Tier 4 standards for engines rated less than 25 hp. For fleets operating in California, the platform’s standard electric standby capability provides an in-use compliance option that meets CARB requirements.
The Vector platform features the company’s E-Drive all-electric refrigeration technology. The latest Vector models use a fully sealed electric scroll compressor that has 70% fewer moving parts and is 200 lbs. lighter than a reciprocating compressor, the company notes. The standard Vector 8100 configuration requires a 460-volt power supply, but the unit may also be equipped with Carrier Transicold’s optional Flex Power dual voltage option, which enables compatibility with 208- to 230-volt sources.
Earlier this year, Thermo King launched the newest model in its Precedent Series. The S-700 is a deep-frozen refrigeration unit with shorepower capabilities and is designed to be fully compliant with EPA Tier 4 standards without the addition of diesel particulate filters or engine emissions systems. The greater-than-25-hp. model is compliant with CARB Ultra-Low-Emission Transport Refrigeration Unit In-Use Performance Standards.
Also built on the Precedent platform from Thermo King is the S-600 model, a single-temperature unit that features two-speed evaporator operation to enhance airflow while hauling perishable goods. Rounding out the line is the C-600, a less-than-25-hp. single-temperature model. The S-600 and S-700 units, the company notes, offer trade cycle flexibility due to their longer useful engine life.
Thermo King’s SmartPower electric standby option is available on all Precedent models. This allows the units to operate on electric power in addition to being powered by the standard diesel engine. During SmartPower operation, power to the unit is supplied by an electric motor connected to a high voltage power source.
Precedent models from Thermo King utilize the manufacturer’s Diesel Direct Electric (DDE) architecture that directly couples a compressor to a diesel engine and employs electrically driven fans and other operating components. Precedent units also feature a belt-driven permanent magnet generator, dual electrically controlled condenser fans, a full width evaporator and dual speed evaporator fan for maximum airflow at low and high engine speeds.
To provide the benefits of environmental compliance and lower cost of operation by reducing fuel consumption, manufacturers are using innovative engineering improvements in their latest trailer refrigeration unit designs.
For more information, visit these websites:
Carrier Transicold
www.trucktrailer.carrier.com
Thermo King
www.thermoking.com
