# Customized Approach to Greenhouse Gas Emissions Calculations in Railway Freight Transport
## 1 Introduction
Since 2019, the rate of emissions growth has continued to decrease, with transport emissions to be reduced in the near future. [PERSON] et al. [26] defined a concept of carbon-saving profit for studying railway freight prices and discussed a maximization model of railway freight based on an established low-carbon economy. [PERSON] et al. [27] mentioned the importance of efficient and feasible approach development for recovering and recycling wasted rolling stocks. [PERSON] et al. [28] discovered that emissions from materials contribute more than nine times the CO\({}_{2\text{e}}\) emissions of machines used in renewal projects, and in addition, that extending the lifespan of rail infrastructure assets through maintenance is beneficial in terms of reducing CO\({}_{2\text{e}}\) emissions. Furthermore, [PERSON] et al. [29] examined the CO\({}_{2}\) impact of railway resurfacing in ballasted track bed maintenance. [PERSON] et al. [30] assessed global warming potentials due to railway tunnel construction and maintenance. The European standard EN 16258 Methodology for the calculation and declaration of energy consumption and GHG emissions in transport (freight and passenger) was approved by the European Committee for Standardisation in 2012 [31; 32; 33]. Currently, there are three main approaches to the measurement of energy consumption and produced emissions [32]: Well-to-Wheel (hereinafter WtW), Well-to-Tank (hereinafter WtT) and Tank-to-Wheel (hereinafter TtW):  
* Well-to-Wheel (the sum total of Well-to-Tank together with Tank-to-Wheel): an approach based on the monitoring of energy consumption and associated emissions production, which covers the whole process from the production of electricity or fuel, through supply to appropriate means of transport via the distribution network, to consumption associated with the operation of transport means. This approach is based on the sum of Tank-to-Wheel and Well-to-Tank values (Figure 1). * Well-to-Tank: Energy consumption and emission production associated with energy or fuel production--this indicator covers all activities from mining of raw materials via energy or fuel production to delivery to relevant means of transport via the distribution network. This indicator does not include the mode of transport (Figure 1). * Tank-to-Wheel: Consumption of energy and associated emissions production connected with transport means operations. This approach does not include the additional life cycle of the fuel and transport means (Figure 1). [PERSON] et al. [33] described a comparison of energy consumption and GHG production of three modes of transport (road, rail and water) according to current legislation--EN 16258. Another option is to use the life cycle assessment (LCA) method and a life cycle cost (LCC) analysis method [34]. These methods summarize energy consumption, GHG emissions, and costs from the perspective of the whole life cycle during the conception stage, construction stage, operation and maintenance stage, and disposal stage [34]. In some cases, the authors describe only these stages: construction, operation, maintenance, and dismantlement or demolition [1; 35]. However, the authors of this manuscript, in contrast to the LCA method, focused only on the monitoring of energy consumption and associated emissions production, which covers the whole process from production of electricity or fuel, through to supply on appropriate means of transport via the distribution network, to consumption associated with the operation of transport means (WtW approach) [32]. Conception, construction, operation, maintenance, and disposal stages in connection with railway infrastructure are not included. Reducing GHG emissions from freight transport can be achieved, for example, by supply chain pooling [36]. Supply chain logistic pooling consists of several independent companies sharing logistic activities and can be initiated for environmental reasons to optimize transportation and reduce the companies' GHG emissions [37; 38]. [PERSON] et al.