Energy transformation is one of the processes shaping contemporary urban transport systems, with public transport being the subject of initiatives designed to enhance its attractiveness and transport utility, including electromobility. This article presents a case study for a metropolitan conurbation—the GZM Metropolis in Poland—considering the economic efficiency of implementing buses with conventional diesel engines, electric buses (battery electric buses), and hydrogen fuel cell-powered buses. The analysis is based on the cost-benefit analysis (CBA) method using the discounted cash flow (DCF) method.

The development of public transport systems is related to the implementation of modern and low-carbon vehicles. Over the last several years, there has been a clear progress in this field. The number of electric buses has increased, and the first solutions in the area of hydrogen fuel cells have been implemented. Unfortunately, the implementation of these technologies is connected with significant financial expenditure. The goal of the article is the analysis of effectiveness of financial investment, consisting in the purchase of 30 new public transport buses (together with the necessary infrastructure–charging stations). The analysis has been performed using the NPV method for the period of 10 years. Discount rate was determined on 4%, as recommended by the European Commission for this type of project. It is based on the case study of the investment project carried out by Metropolis GZM in Poland. The article determines and compares the efficiency ratios for three investment options-purchase of diesel-powered, battery-powered, and hydrogen fuel-cell electric vehicles. The results of the analysis indicate that the currently high costs of vehicle purchase and charging infrastructure are a significant barrier for the implementation of battery-powered and hydrogen fuel-cell buses. In order to meet the transport policy goals related to the exchange of traditional bus stock to more eco-friendly vehicles, it is necessary to involve public funds for the purpose of financing the investment activities.

Symbiosis and synergy among urban uses are key determinants of spatial quality, liveability, and resilience. While symbiosis denotes the coexistence of users and functions within specific places, synergy refers to the collective benefits emerging from their interaction. These dynamics are especially relevant in city centres and main streets, which serve as structural and social backbones of urban life. This article applies the SyM_SyN Method to Zwycięstwa Street in Gliwice, Poland, to assess the intensity and distribution of symbiotic and synergistic relations. The analysis identified significant spatial deficiencies that weaken the coherence and attractiveness of the street. The results demonstrate how a systematic, data-driven evaluation can expose hidden weaknesses in urban structures. Importantly, from the perspective of the smart city paradigm, liveability and responsiveness of urban spaces cannot be reduced to technology-driven systems of sensors and devices. They must also be understood in terms of human-scale interactions and the ability of urban form to support them. Beyond its methodological contribution, the study emphasises the practical implications for urban renewal: reinforcing positive interactions between adjacent uses enhances street vitality, improves social inclusiveness, and supports more sustainable development strategies. The SyM_SyN Method thus provides both an analytical framework and a decision-support tool for designing user-oriented, high-quality urban spaces within the broader smart and sustainable city paradigm.

Purpose: The purpose of the research is to compare the impact of inclusion emissions at source on environmental and economic performance of replacement of combustion engine powertrain with the electric or hybrid one, given the transport work on a selected public transport line on urban areas. It provides the gross emissions of pollutants and greenhouse gases related to total transport work executed on given bus line. Design/methodology/approach: Primary data was collected from one of the public transport operators running its business in Upper-Silesian and Zaglebie Metrpolis, covering the western part of its territory. The company is undergoing the multiannual process of fleet replacement, justifying its investment decision with environmental factors, including emissions. The operator provided the author with the following data: consumption of diesel fuel depending on bus size and Euro emissions standards, consumption of power for charging electric buses, average daily and annual mileage. It facilitated the author to construct scenarios of annual transport work per vehicle and analyze the emissions respectively. Findings: Electrification of public transport delivers positive environmental effects resulting in reduction of local emissions of pollutants and greenhouse gases. If the emissions of the source of power are included in the calculations, the benefits are lower, but it is possible to increase them by modification of the energy mix of supplied power, by significant increase of share of environmentally neutral or green energy. Research limitations/implications: If possible, there could be conducted further research covering emissions related to production of diesel fuel and hydrogen (per unit), as no other fuels are practically in use. Practical implications: Analyzed case provides the public transport operators with knowledge on their actual emissions and facilitates them to adjust the structure of the fleet in use to lower the environmental impact. Originality/value: The paper addresses the issue of zero-emission transport. Originality of the approach results from inclusion of the environmental effects of power generation source in the environmental effects of electrification of fleet in public transport. Keywords: public transport emissions, electromobility, electric bus, hybrid bus, diesel bus. Category of the paper: research paper.