This study has succeeded in developing an understanding of the changes that have occurred over the last fifteen years in the international trade of refrigerated cargoes. The following are the major conclusions of the study: (1) The leakage rate of refrigerant has decreased from 25% to 5% per year during the lifetime of a Refrigerated Shipping Container, RSC; (2) The monetary value of typical loads in a RSC has increased to an average of $300,000, and comprehensive maintenance and pre-trip inspections of RSCs insure that these valuable loads arrive to the consumer as a high quality product; (3) A RSC has a higher quality refrigeration system than a Trailer Refrigeration Units, TRU, that are used to transport refrigerated containers on US highways; (4) The large increase in the use of intermodal RSCs for international export and import has resulted in a significant increase in the use of diesel electric generator sets to power the RSCs during their transport to rail yards and to off dock warehouses near the ports; (5) The amount of diesel fuel used to power RSCs in the port areas is estimated to be much larger than that used to power idling trucks in the port itself; and (6) RSCs are in very high demand during peak season for agriculture products, and they are stored inside the ports to meet peak season demands.

Based on the data and information we have obtained in this study, we are able to obtain the following estimate for the emissions related to RSCs in MMTCO2E in the port areas: (1) Decommissioning of Shipping Containers-0.0975; (2) Leakage of Refrigerant-0.0855; and (3) Shipping Container Diesel Engines-0.289. These estimated results are considerably lower than previous estimates.

The RSC industry has extensively tested the use of CO2 as the refrigerant, and plans are in place to introduce CO2 RSCs into a large portion of the RSC fleet in the coming years. A final observation is that the large container ships currently being built are among the most environmentally friendly vessels in the world. Their thermal efficiencies are increasing and emissions are continually being reduced.