The discussion about 15-minute cities (also referred to as cities of short distances) has gained considerable momentum in the last decade. Thanks to the optimal spatial layout of these urban areas, their residents can meet most or all of their day-to-day needs within a short walk or a bicycle ride from their place of residence. This is especially important in the context of problems currently faced by most large agglomerations worldwide, the negative externalities caused by predominantly motorised transport and inappropriate spatial planning policies that entail substantial environmental and technical infrastructure outlays. The concept of spatial proximity to services played a key role in the empirical part of the present study, where Krakow’s layout was analysed in detail from the perspective of a 15-minute city. Krakow is a resident-friendly, inclusive city created primarily with local communities in mind. However, certain design flaws in terms of spatial proximity to services prompted us to reconsider how its specific spatial components operate. To achieve the study’s goal—a comprehensive assessment of Krakow as a 15-minute city—we proposed several solutions that can be made universally adaptable for other urban areas striving to meet the short distance criteria.

Urban sprawl is a process shaping the space of contemporary urban areas. The costs generated by this phenomenon force central and local authorities to adopt and implement a spatial policy limiting those costs. However, there is no method in Polish spatial policy that determines the extent of this phenomenon around cities, and thus identifies the area of intervention. Therefore, the purpose of the article is to propose a method of delimitation of urban areas at risk of urban sprawl. The proposed method of delimitation honors the characteristics of urban sprawl relating to spatial structure, socio-economic processes and efficiency of spatial policy. The method can be useful for conducting spatial policy aimed at reducing costs due to urban sprawl. It particularly pertains to the policy implemented at the central and regional level. Research results indicate that, in most Polish urban areas, delimitations used thus far designate too little of the area around core cities. Although the goals of reducing the negative consequences of urban sprawl are formulated at the level of national spatial policy, the methods of delimitation used thus far do not take into account the specificity of this phenomenon. Underestimating the extent of urban sprawl results in a lack of effectiveness of spatial policy due to the omission of specific areas in public intervention. This particularity is related to the fact that these are usually external areas—the most distant from the core city. These areas have the highest costs for urban sprawl. At the same time, these are areas in the early stages of spatial growth, in which a consistent spatial structure can still be kept while implementing proper spatial policy.

Urban sprawl is a process that shapes contemporary urban spaces. Generally, this process is associated with negative effects due to the generation of high costs. However, not all the effects of urban sprawl should be considered in the context of the increasing costs of the use of space; some of them should be regarded as cost cutting factors, for example, the possibility of the use of roofed areas in generating energy from sunlight. Solar energy is believed to be one of the sources of clean energy that reduce pollution and greenhouse gas emissions into the atmosphere. However, solar energy generation necessitates the development of large areas for the purpose of installing photovoltaic modules and substantial funds for creating large solar farms. For this reason, a significant role in state energy policies is played by small dispersed installations mounted on the roofs of buildings. There is a gap in existing research on the assessment of urban sprawl in terms of the potential use of rooftops for solar installations in suburban areas. This research gap has not yet been filled, either conceptually and methodologically. Hence, the contribution of the research to the development of the current state of knowledge involves the identification of economic and environmental benefits of usually negatively perceived urban sprawl. The proposal of a method for the identification of suburban housing potential for solar energy generation constitutes another addition to the state of knowledge. The main objective of this article is to analyse the energy generating potential of buildings located in suburban and urban areas characterised by the confirmed occurrence of urban sprawl phenomena. CityGML data were used to conduct an analysis of the exposure of roofs to sunlight using algorithms based on vector data. The authors estimated the dynamics of changes in time and referred the existing photovoltaic installations to the total potential of a selected area. The use of the energy potential of the analysed roofs of buildings was used to evaluate the external costs and benefits of spatial planning. The discussion presented the current conditions of the energy sector and energy policies in Poland and the EU. In addition, recommendations were proposed for local spatial policies concerning the mitigation of the effects of suburbanization in the context of developing the system of PV micro-installations.

There are important relationships between the urban sprawl process and economic growth. They are usually expressed through spatial relations and changes taking place in the local, regional and national economy. The temporal and spatial dimension, including dispersed location, are the determinants of development and economic growth. Therefore, the urban sprawl phenomenon and the related location, hypothetically conditioning economic growth, should be subject to macroeconomic research. The article examines how urban sprawl affects the national budget and national economic growth. Unlike many studies where urban sprawl is studied by scattering the population around cities, we undertake more complex examination using buildings’ location. Urban sprawl, as we understand it, is a spontaneous spread of buildings around cities. To assess the spontaneity, we use a grid of squares with a side of 500 m. The squares are used to calculate the morphological indicators of urban sprawl. Therefore, quantified urban sprawl is one side of the equation; on the other side are macroeconomic variables. In this way, we examine the relationship between urban sprawl and the national budget and economic growth of Poland. The conclusions obtained are, e.g., urban sprawl does not have a negative effect on the national economy and the budget. This is a different conclusion from those thus far. There are also different conclusions on the regional level. Based on the research results, we formulate recommendations for national economic policy and spatial policy.