A Low Emission, Electrified Solution for Refrigerated Trucking

摘要

Multiple factors are driving commercial trucking toward electrified solutions to lower harmful greenhouse gas emissions, improve efficiency and reduce fuel consumption. As part of this, the refrigerated trucking industry is searching for methods to meet these new requirements. Currently, most refrigerated truck solutions use a diesel engine to provide power for the refrigeration system. This diesel engine is a source of pollutants which are federally regulated by the Environmental Protection Agency (EPA) and state regulated by groups such as the California Air Resource Board (CARB). In addition, this diesel engine is a source of noise and excessive fuel consumption. Today electric systems do exist in the form of eutectic plate evaporator systems. These systems utilize electric compressors which are plugged in at night to freeze a bank of eutectic plates. During the delivery route these units use the stored cooling in the plates to keep product cold. This operation leads to low emissions, but route duration and box temperature control can pose a challenge preventing these units from being used in some applications. A refrigeration system has been developed which significantly decreases carbon dioxide impact and eliminates fuel consumption while at the same time allowing for precise temperature control for an entire 10-hour route. The system utilizes a fully electric condensing unit featuring a high efficiency variable speed scroll compressor with economized vapor injection and 48-volt input variable speed drive. Inside the refrigerated body is a dual evaporator system consisting of eutectic plates and direct expansion evaporator. Powering the system is a 48-volt battery pack which is charged by utility power at night and via solar panels during the day. The entire system is controlled with a single system controller which is programmed to optimize both efficiency and reliability. This paper will present the system design, estimates of anticipated performance and field test data to validate these estimates. Results will be compared to traditional refrigeration technologies.