Temperature-controlled distribution with  refrigerated vehicles to the final consumer   

For the pre-run of the temperature-controlled transports, it is assumed that there is a  direct load transport between the producer and the cooling house with a 7.5-ton  HGV, which has an estimated volume-related cargo loading factor of 0.38. In this case, the volume-related cargo loading factor is limited by the weight-related maximum load. There are CO2-equivalent emissions from fuel consumption that are generated both by the actual vehicle movement (18 l /  100 km) and the use of the cooling units (3 l /h). In addition, coolant losses in the vehicles and the cooling houses cause emissions, which, however, are not included in the calculation by means of cut-off criteria. In order to be able to keep calculations comprehensively clear with all the complexity of the systems, one agreed on cut-off criteria. These determine the proportion from which an input is no longer relevant for the calculation. As a rule, the limit is 1 % of the input of the total system in relation to mass, energy or environmental relevance since it is assumed that minor inputs below this limit have no appreciable influence on the overall result and therefore there is no need of further consideration [10]. Although the special vehicle bodies of the refrigerated vehicles and the construction of the cooling houses are made of materials that have high characterization values (e.g. aluminum with 16.1 kg CO2e).  But this may only be attributed to the individual functional unit on a pro rata basis. For a typical depreciation period of 9 years of vehicles with average use, the proportion of the emissions generated for the individual product is so low that this is not taken into account in the calculation. The energy consumption during transshipping is similar. It has to be pointed out, that the use of cooling houses causes emissions, but these also do not flow into the calculation because of the cut-off criteria [10]. In the main run, direct transports are carried out between cooling houses with 40-tonnes HGVs with an average volume-related cargo loading factor of 0.63. Here CO2e  emissions are generated by fuel consumption for vehicle movement (31 l / 100  km) and for the use of cooling units (5 l / h). The critical section of the three delivery phases is the post-run, where the calculations are based on round trips between cooling houses and final consumers. Deliveries are carried out with a 3.5-tonnes HGV, which have an average volume-related cargo loading factor of 0.28. Fuel consumption for the vehicle movement (10 l / 100 km) and the use of the cooling units (4 l / h) generate CO2e emissions. The increased fuel consumption of the cooling units with respect to the loading volume is caused by the frequent opening of the cooling cell. 

Delivery using EPS-Packaging by means of  CEP service providers   

In the online frozen food trade, the use of insulating containers made of EPS and dry ice as coolant is increasingly being used due to its good scalability. Such delivery solutions can be operated without external cooling, for example, the “NextGeneration Thermopack”  from K+S over a period of 72 hours. Dry ice is used, which is solidified carbon dioxide (CO2) and sublimes under normal pressure at a temperature of around – 78.5°C. Thus, a sufficiently low temperature is provided for the cooling and the solidified gas does not melt but passes directly into the gas phase without residue. The carbon dioxide used for the dry ice can be deposited as a by-product in combustion processes. After a multi-stage purification of the combustion gases, the pure carbon dioxide under pressure and low temperatures can be liquefied. Liquefied CO2 is optimal for transport and storage. Dry ice can be produced in different shapes and sizes. For the use as a coolant in insulated containers, a pellet shape is suitable, since these are easy to produce and to handle. In order to produce the pellets from the liquefied gas, the CO2 is suddenly expanded to normal pressure. The evaporation and adiabatic expansion result in a cooling that is large enough to produce dry ice snow, which can be compacted and pressed into the desired shape.  The subsequent release of the carbon dioxide can be regarded as CO2-neutral since existing combustion gases are used and the deposition only means a delayed release to the environment and no additional load. There are only a few more emissions from the deposition, the liquefaction, the pressing and if necessary the transport of the liquid carbon dioxide or the dry ice to the place of application. The 10 kg dry ice are calculated with 1.39 kg CO2e and for the EPS-container with a useful load volume of 35.5 liters, there are  1.15 kg CO2e emissions. It can be assumed that there are a 27 %  material and a 40 % thermal utilization of the insulating EPS-packaging. The use of these EPS-packaging and dry ice allows the delivery by means of conventional CEP service providers, which have a very efficient distribution system. The analysis of this scenario is also based on a three-level distribution. The pre-run is carried out by means of 7.5-tonnes HGVs, which have a cargo loading factor of 0.63 and an average fuel consumption of 20 l / 100 km. In the main run, 40-tonnes HGVs are used for the direct transports that have a cargo loading factor of 0.9 and an average fuel consumption of 34 l / 100 km.  The post-run is realized through 3.5-HGVs with a cargo loading factor of 0.4 and fuel consumption of 10 l / 100 km. In order to evaluate EPS-packaging disposal, two standard EPS-Packaging solutions were tested. The packaging’s dimensions were 48cmx48cmx38cm and 26cmx21cmx18cm (LxWxH), with a thick of 4 cm and 3 cm respectively.

Temperature-controlled distribution and final  consumer’s shopping trip

This scenario represents the classic distribution to the supermarket and the subsequent shopping trip of the final consumer. In this scenario, deliveries of larger quantities of frozen foods are exported from the producer to the cooling house of supermarket chains. For this purpose, consolidated transports are carried out with a 40-tonnes HGV with a cargo loading factor of 0.8 CO2e  emissions generated by the fuel consumption for vehicle movement (33 l /  100 km) and the use of cooling units (5 l / h). The main run is represented by  7.5-tonnes HGV that supply the supermarkets and have a cargo loading factor of 0.38, producing CO2e emission due to fuel consumption for vehicle movement (18 l / 100 km) and use of cooling units (3 l / h). The transshipping and the storage in the supermarket takes place in freezer cabinets with a load volume of 770 liters and a power of 300 watts [11]. In the post-run the final consumer drives in its own car an average distance of 5 km to the supermarket with an average fuel consumption of 8 l / 100 km. Frozen foods take a proportion of 20 %.