Validering av sjötransporter i Samgodsmodellen: version 1.1

Download
Jonas Westin

The project analyzes how well sea transports are modelled in the Swedish national freight model system Samgods. This first report comprises a short description of Version 1.1 of the model including calibration, a comparison of model results and statistics in 2012 as well as sensitivity analyses to test how the model reacts to different types of interventions. The second report, VTI notat 31-2016 Modeling of loops in maritime transport Case Study of SCA's RoRo operations in the Baltic Sea, examines how big the problem is that Samgods does not model loops (vessels calling more than two ports during a trip).

The existing Samgods model is a deterministic cost-minimizing model. It consists of several partially interacting modules: a) base matrices that describe the demand for 32 commodities, b) the logistics model that contains submodules for the choice of consignment size, consolidation of shipments from different senders, choice of transport chains, treatment of empty transports etc. and c) the rail capacity management tools (RCM) addressing capacity constraints in the Swedish rail network.

The calibration of the model focuses on tonne-km and modal split in Sweden as well as different regional distributions of the tonnes transported, but the distribution over vessels types is not taken into account. Our analyses show that the model calculates about four times as many tonnes transported by container vessels than the statistics. We see a need to check if the input data used for the modelling of container transports (vs conventional transports) is realistic.

Throughput (loaded/unloaded tonnes goods) was calibrated for 14 coastal sections and twelve aggregated commodities. However, we believe that the throughput per port should be a calibration target. The distribution of the gods on the ports is crucial in analyses of investments in fairways, locks etc.

Furthermore, the distribution of the port calls vessel categories and -size classes was not a calibration target. We show that Samgods model overestimates the number of calls to all freight vessels with about 50 percent. The number of container vessel calls is about five times higher as in the Swedish Maritime Administration’s database. The number of roro-vessel calls is about two times as high. The conformity for the other vessels is very good.

MEET US


25-27
Aug

ICTTP 2020

ICTTP, International Conference on Traffic and Transport Psychology, is postponed until August 2021.
9-11
Sep

European Transport Conference

The ETC, European Transport Conference will be organized in an online format.
13-14
Oct

Society for Benefit-Cost Analysis: European Conference 2020

VTI and Centre for Transport Studies (CTS) at Royal Institute of Technology (KTH) organise Society for Benefit-Cost Analysis: European Conference 2020. 

LATEST NEWS


2020-06-18

Additional policy instruments are needed to achieve Swedish environmental quality objectives for maritime transport

Achieving the national and international environmental objectives for maritime airborne emissions requires a combination of new and more powerful policy instruments. The policies already in place are not enough. This is one of the conclusions of a research...


2020-06-16

Opportunities for a new market in electrified regional flight

Large, electrified aircraft is far off in the future. On the other hand, there may be potential for a new market with smaller regional flights. These are the conclusions of a literature survey made by researchers at VTI.


2020-06-15

Need for standards as electric road systems are developed

The need for standardisation is increasing as electric road systems are reaching higher levels of maturity. A large part of the standards for intelligent transport systems (ITS) assessed in a new VTI and SIS study was considered potentially useful for...


2020-05-25

Unique knowledge compilation on microplastics from road traffic

Although we know that tyre and road surface wear generates significant emissions of microplastic particles, knowledge about them is very limited. This is the conclusion of a report issued by the Swedish National Road and Transport Research Institute (VTI).


2020-05-25

Measures for infrastructure climate adaptation requires prioritisation

The effect of climate change will result in more extreme weather events causing for example increased risk of floods, and landslides, which will result in great costs to society. Therefore, society needs to prepare for the consequences brought on by climate...


2020-04-16

Increased interest in train simulators

VTI has developed a train simulator that has become a valued tool in train driver education and research on how simulators can be used to improve railway technology.