• Energy Research

The article analyzes and evaluates costs, transport time and CO2 emissions by selected vans. The research was carried out on the example of three models of Iveco Daily vehicles powered by: diesel oil, electricity and compressed natural gas (CNG). The result of the research presented in the article is the determination of the operating costs of vehicles powered by various energy sources and the level of CO2 emissions. The comparative analysis was carried out on real data for the established transport task. Vehicles with engines powered by compressed natural gas are characterized by the highest savings in terms of transport costs. As the authors pointed out, this may be due to the fact that this type of engines, despite the low interest of buyers at the moment, may gain much more popularity in the future. On the other hand, in relation to vehicles with electric motors, the cost of transport is the highest, which means that this type of technology is ineffective in relation to long-distance transport.

The correct operation of the continuous welded track requires diagnosing its condition and preparation of track metrics requiring measurements of displacements of rail under operation. This is required as there are additional thermal stresses in the rails with values depending on the temperature changes of the rails. Therefore, the climatic conditions are important. This paper presents the original effective analytical method for diagnosing the condition of continuous welded track based on experimental research. The method allows for an appropriate repair or maintenance recommendation. In the experimental research, the authors considered track diagnostic conditions for two conditions: track under load and track without load. This paper presents empirical formulas for calculating rail temperature and longitudinal force based on ambient temperature, developed from long-term measurements. The formulas were developed for a track located on a straight section—both for a rail loaded and unloaded with a passing train under the following conditions: 60E1 rail, not on an engineering structure, conventional surface, wooden sleepers and very high train traffic load. The obtained results in the value of the correlation coefficient R2 ≥ 0.995 attest to very high accuracy of the calculations performed with the method proposed by the authors.

Nowadays, apart from travel time and cost, more and more attention is paid to ensuring that ecological footprint of the means of transport used for a journey is as small as possible. Therefore, it is reasonable to look for methods and solutions that will allow planning communication connections according to the principles of sustainable development. The aim of the article was to present mathematical model of the proecological distribution of traffic flow into a network, together with a determination of how the amount of emissions of harmful compounds for rail transport will be calculated (based on amount of energy necessary for movement, calculated on circumference of the wheels). The model has been verified on real data. The traffic flow was distributed over a selected communication route: Warszawa—Gdansk, where the criterion was minimization of total carbon dioxide emissions. An evolutionary method implemented in Microsoft Excel was used to solve the optimization problem. For the analysis of only the fastest connections, the railway one was the optimal from the point of view of the adopted criteria. After the train capacity was exceeded, air and car connections were loaded. Based on the research, a function that represents the amount of carbon dioxide emissions in the analyzed traffic route depending on the size of the traffic flow was developed.

As a result of the COVID-19 pandemic, the ongoing war and the implementation of the so-called Mobility Package there are profound changes taking place in the Polish LSP sector. The competitive struggle on the market is intensifying, and it mobilizes the management to diagnose the condition of companies with the use of effective comparative tools. This article aims to present the conclusions of the study of 46 entities on the Polish LSP market. It uses an original, multi-faceted evaluation method. The authors hope to popularize this method for evaluating LSPs by making it cyclical. The comparative evaluation of LSPs was carried out with the use of economic (index) and statistical analysis tools. A model of rank correlation was used for the values of all variables (ten economic parameters and one greening parameter). LSPs were grouped up based on the average value of the economic variables and according to investment attractiveness and then clustered. Sets of the most correlated characteristics in the assessment of the LSPs were developed based on the k-means method and the Spearman coefficient. A collective ranking of LSPs has been prepared.