Hybrid Reefer Offers Big Savings

Using hybrid diesel/electric technology, Carrier Transicold says it is able to bring significant life cycle savings to reefer operators with its newly launched Vector 1800 MT. The revolutionary Deltek (Diesel-Electric Technology) reefer system uses the same 2.2- liter Kubota diesel engine that powers Carrier's Ultra and Ultima reefer units, but that's about all it has in common with existing equipment.

Key to the performance and reliability of the Vector is the electric power for the reefer components, generated by the diesel engine and a special generator, supplied by United Technologies' partner company, Hamilton Sundstrand, a leading aerospace supplier.

This generator supplies power for the electrically driven compressor from the marine side of Carrier's business, where refrigeration systems of great reliability run unattended on container ships during lengthy trans-oceanic voyages. Electric power is also used for fans, the heating and defrost cycles of the reefer unit and for battery charging. And because the refrigeration side of the unit is electric, the Vector offers 460-volt plug-in standby as part of the package.

SIMPLE RELIABILITY

Most of the problem areas associated with reefer maintenance and leakage are addressed using the Deltek hybrid technology. Because the compressor is electrically powered, there is no mechanical drive from the diesel engine and therefore no potential refrigerant leakage through the power shaft seal. In fact, the whole six-cylinder, high-performance compressor and motor assembly is sealed, with only electrical and refrigerant connections passed through the housing.

And because electric resistance power strips are used for the heating and defrost cycles, the refrigeration circuit is far simpler, with no need to incorporate a hot gas heating cycle. As such, the Vector has no solenoid valves or check valves or any of the associated pipework. And it uses only about half as much refrigerant as a conventional transportation refrigeration unit.

Further simplifying the unit is the use of electric, instead of mechanically driven, fans. Not only does this allow for more accurate tailoring of cooling and discharge, but electric power also means no complicated and trouble- prone belts and belt adjustments. It also makes for a more compact unit than conventional reefers. Gone are belts, idler pulleys, vibrasorbers and clutches, along with the associated need for regular service. In fact, the only belt is the alternator drive belt on the Kubota engine.

With up to a 66 percent reduction in parts and the use of the aerospace generator and ultra-reliable container-ship motor/compressor, Carrier is predicting a reduction in life cycle costs of 30 percent, with an extended service package included that allows for 3,000 hours, which could be as much as two-year intervals.

Further savings in fuel cost come from the optimization of the hybrid drive arrangement and the built-in electric standby, allowing for significant fuel savings at the loading dock.

An impressive benefit that comes with a reduction in the mechanical complexity is a substantial reduction in noise while the unit is running. Not only is the sound level less, but the quality of the noise is much less irritating, a major benefit in urban delivery situations.

MULTI-TEMP APPLICATION

While Deltek is new to North America, it has been running for several years in Europe, where it is a proven technology. It is being introduced here initially as a reefer unit for multi-temperature trailer applications, since these are among the more demanding and also because multi-temp applications are on the increase. According to Carrier, the unit can be used with single or dual discharge evaporators in up to three compartments in a reefer trailer.

Adding to the versatility of the new Vector 1800 is the Advance microprocessor control that delivers precise refrigeration control, easy set-up and exclusive fuel optimization options. Advance control has two programmable software features: IntelliSet and ProductShield.

With IntelliSet, a fleet manager can set up as many as 30 commodity profiles – each with its own characteristics for temperature control – from the Carrier PC-based ReeferManager software.

These profiles can have names that reflect the commodity. Once they are uploaded to the Advance controller, a driver simply scrolls through the list to find the commodity – strawberries, frozen fish or ice cream, for example. Profiles can be established fleetwide once the parameters are set. The Advance microprocessor automatically adjusts for the best temperature control at the optimized fuel efficiency mode depending on the selected commodity.

ProductShield uses information from temperature sensors inside and outside the trailer to determine whether to use continuous- run or auto stop/start for any given commodity according to ambient conditions. In its latest 4.03 release, the Advance software offers additional fuel economy in high-air mode.

CHOOSING ELECTRIC STANDBY CAPABILITY

Running a conventional refrigeration unit from an AC electrical source involves a relatively expensive add-on. But electric standby capability is growing in importance to refrigerated haulers for several reasons:

• Conserves diesel fuel for the road.

• Reduces engine wear.

• Eliminates emissions from the refrigeration unit.

• Eliminates engine noise during loading and unloading, important for supermarkets and restaurants located in residential neighborhoods.

With California Air Resources Board's recent Airborne Toxic Control Measure, maybe the most important benefit of standby is it complies with regulations, especially in California, where use of electric standby at the loading dock is one of the approved methods for compliance with diesel emissions regulations. (To learn more, go to www.arb.ca.gov/diesel/tru.htm.)

The use of electric standby also adds up to reduced operating costs. Calculation shows a refrigeration unit run on electric standby is less expensive than powering it from the diesel engine – an estimated savings of more than 50 percent. The reduced engine use also translates into reduced maintenance for even greater operational savings. Because it is a diesel-electric hybrid, the Vector has electric standby capability built in.