Block Typology Research Articles

Optimizing Solar Power Generation in Urban Industrial Blocks: The Impact of Block Typology and PV Material Performance

The block-scale application of photovoltaic technology in cities is becoming a viable solution for renewable energy utilization. The rapid urbanization process has provided urban buildings with a colossal development potential for solar energy in China, especially in industrial areas that provide more space for the integration of PV equipment. In developing solar energy resources, the block layout and the PV materials are two critical factors affecting the distribution of solar radiation and generation. However, few studies have analyzed how to select the most suitable PV materials for different layouts of industrial blocks to obtain the best generation. This study considered the layout of industrial blocks and PV materials simultaneously, and the generation yield was calculated when combined. A total of 40 real industrial block cases were constructed, and radiation distribution data on building surfaces of different block cases were calculated. Data on both were combined to calculate the generation of different PV materials for each block type. The findings indicated that single-story industrial blocks possessed the highest potential for solar radiation, primarily due to the higher percentage of roof area. The influence of PV materials on the installation rate of different building facades varied, with the installation rate of the west facade being the most impacted by PV performance and the roof being the least impacted. Using different PV materials in industrial blocks could lead to a 59.2% difference in solar generation capacity. For single-layer industrial blocks, mono crystalline and poly crystalline silicon were preferable to achieve higher power generation. In contrast, multi-story and high-rise industrial blocks were best suited for a-Si and CIGS to attain higher cost performance. The methods and results of this study guided the selection and installation of PV equipment in various block typologies, thereby improving the refinement of solar resource development, maximizing solar resource utilization, and promoting the development of energy conservation and carbon reduction in cities.

Discovering urban block typologies in Seoul: Combining planning knowledge and unsupervised machine learning

Urban blocks are fundamental elements of urban form and play an important role in urban development. Identification of their typologies has been a long-standing challenge in urban planning and design. Traditionally, expert-based classification has been used, but recent studies have shifted towards data-driven clustering to achieve better results. However, most studies tend to use only one of these approaches and few integrate both. To address this gap, this study proposes a framework that combines planning knowledge and machine learning to identify urban block typologies in complex urban environments. The framework first classifies blocks based on their size types according to planning regulations and development types. Then, a combined hierarchical and Gaussian mixture model is used to discover clusters with complex feature data distributions. These clusters are translated into block typologies using a semantic naming system and illustrated with representative blocks. Finally, the validity of the results is tested by comparing them with other building features, such as building age. The proposed integrated framework was applied to Seoul, resulting in the discovery of 27 residential block typologies across the entire city. These typologies show significant correlations with the average building age in the blocks. The application of expert knowledge in the clustering method demonstrates higher accuracy compared to conventional clustering approaches. Overall, this framework holds significant potential for discovering urban block typologies that are consistent with planning domain knowledge and provide urban planners and designers with valuable insights into the characteristics of urban block typologies, thereby helping decision-making regarding zoning regulations, urban design, and urban development strategies.

A Spatio-Temporal Analysis of the Urban Fabric of Nuremberg From the 1940s Onwards Using Historical Maps

As one of the most heavily bomb-damaged cities in Germany, with around 90% of its historic city centre destroyed, Nuremberg (<em>Nürnberg</em>) provides an excellent example to investigate the urban transformation of a post-war city. In this article, we bring together heterogeneous and under-researched data sets and archival material from the post-war period and convert urban features depicted in historic maps and scanned documents into digital geospatial data that is analyzed with a geographical information system. We combine morphological variables of townscape analysis to present three different transformations over time. First, using a damage map of Nuremberg from the Second World War, we examine the varying extent of bomb damage across the city at the detailed district level. Secondly, we focus on land-use units, comparing the pre-war spatial land-use distribution from 1940 with historical maps of land use/cover from 1956 and more recent land uses in 1969. Finally, using selected characteristics of urban form, we categorize pre-war and present-day urban block typologies to examine urban morphological change. In doing so, we contribute methodologically and substantively towards a new framework for the analysis of post-war cities. We demonstrate how geographical information systems can be utilized for historical research and the study of change in urban environments, presenting a map-based interpretation of the planning strategies to have guided post-war urban development in Nuremberg. Providing an alternative appraisal of post-war city transformation, our diachronic research offers insight into Nuremberg’s under-researched past, which is also of interest to planners and policymakers seeking to improve future cities.

The diffusion of traffic pollutants in different residential blocks based on spatial morphological clustering

With urbanization, air quality problems attributed to traffic pollutants have increasingly attracted attention. Residential blocks are the basic spatial units directly related to the quality of the human living environment. Block spatial configuration optimization could effectively reduce the impact of pollutants on humans. The main objective of this study consists of investigating the impact of the different residential block typologies on traffic pollutant diffusion. This paper statistically analyzed various spatial morphological parameters of 236 real residential blocks in Wuhan and divided them into five block types via the k-means clustering method. Then, typical representative blocks of each type were identified. The wind environment and traffic pollutant concentration distribution in five typical representative blocks were simulated via the computational fluid dynamics (CFD) technique, and the influence of the different block types on pollutant diffusion was analyzed. This study found that residential blocks in Wuhan could be better classified according to four types of morphological parameters. The traffic pollutant diffusion routes and distribution in the different type blocks varied. Most pollutants entered the block podium through roof openings. The lateral sides of the adjacent external spaces of street canyons comprised the main channels through which traffic pollutants entered blocks. According to data analysis, the morphological indicators of the block clustering have a certain correlation with the dispersion of traffic pollutants. This paper introduced a novel workflow for traffic pollution studies in actual blocks that can be used as a reference for urban design practitioners.

Spatial pattern of burglary in residential neighbourhoods: a case study of Abuja, Nigeria

PurposeAbuja, the capital city of Nigeria, is one of the fastest growing capital cities in sub-Saharan Africa. Recently, the city is experiencing an alarming rate of burglary and violent crimes, while the city planning management frameworks lacks adequate and effective crime mapping, monitoring and management techniques necessary for achieving liveable and safe environment for habitation despite its grandiose spatial planning and aesthetically appealing architectural design as a modern city. Based on police crime records (2007–2018) and geospatial analysis, this paper aims to provide adequate understanding on the interplay of land use configuration and burglary crime formation in residential neighbourhoods of Abuja, Nigeria.Design/methodology/approachThe methods used for the purpose of data collection includes; field survey, Block Environmental Inventory, while inferential statistics and Geographic Information System tools was used for data analysis. The analysis established that Lagos, Nsukka and Enugu Streets are hotspots; while Chief Palace street, Ladoke Akintola and Oka-Akoko streets were found to be cold spots.FindingsThis study, however, established the applicability of crime pattern, opportunity theory and routine activity theory in understanding the rising burglary crime events in the study areas and the link between physical characteristics of street block typology and burglary crime pattern. The results of the analysis has in a way affirmed the positions of the theories, while disagreed with them in cases where the results indicated contrary outcome.Originality/valueThis paper concluded with inference drawn from the results that supported mixed-use development but with built-in crime prevention through environmental design strategies as effective burglary crime prevention mechanisms that contribute to crime rate reduction.

Urban buildings configuration and pollutant dispersion of PM 2.5 particulate to enhance air quality

A pivotal element for metropolitan planning and an essential component describing the urban design is block typology, affecting the pollution concentration. Consequently, this research examines the influence of various urban block typologies on urban pollutant distribution. Four typologies are simulated by ENVI-MET software. These typologies are cubic-shaped, L-shaped, C-shaped, and linear-shaped models. Urban air quality was assessed using relative humidity, temperature, and pollution PM2.5 concentration. The performance of typologies in terms of temperature, relative humidity, and reduction of air permeability is strongly dependent on the blocks' orientation, the block shape's rotation concerning the horizontal and vertical extensions, the height of the blocks, and the type of typology. According to these parameters, the performance is different in each of these studied typologies. Regression models propose a more reliable prediction of PM2.5 when the independent variables are temperature, relative humidity, and height of buildings, among various block typologies. Hence, this article suggests a machine learning approach, and the model evaluation shows that the Polynomial Linear Regression (PLR) model is excellent for measuring air pollution and temperature.

Impact of Urban Street Network on BIPV Generation Capacity of Buildings

Climate change necessitates a critical reconsideration of the built environment since buildings are among the top fossil fuel consumers. Solar energy generation through building integrated photovoltaic (BIPV) systems is one of the most common onsite energy generation methods. However, many factors regarding urban morphology can negatively affect BIPV generation. Urban block typologies and spatial patterns are commonly studied descriptive metrics of an urban morphology that affect the solar energy potential. Similarly, the street network pattern is a measure of the spatial quality of an urban environment. Although various urban morphology indicators have been extensively studied in relation to solar energy potential, a comparative analysis of urban fabric focusing on street network patterns is also needed. In this study, four representative urban areas with different morphological characteristics are studied. The selected morphologies are parametrically modelled and compared with different building height configurations. A comparative analysis of BIPV generation capacity per square meter façade or roof area is presented. Urban areas without a dominating street network pattern have resulted in greater PV generation on facades, whereas the impact of urban morphology was found negligible for roof PV potential. The findings of this research have the potential to aid in urban planning and architectural design decisions, as well as the efficient use of BIPV systems in diverse urban morphologies.

Building Assessment and Statistical Characterisation of the Mediterranean Social Housing Stock in Southern Spain

Given that the existing residential buildings are expected to become a huge part of the future stock due to their low replacement rate, retrofitting plans are crucial to meet 2030 and 2050 energy efficiency targets. Notwithstanding, an extensive assessment of the current energy and thermal performance of the stock must be conducted prior to the proposal of energy saving measures in order to properly tackle the retrofit process. Thus, the analysis and characterisation of the existing buildings under real variability conditions through statistical techniques is key to provide useful information at the stock level, instead of the most commonly single-building level approach. In the presented study, a statistical analysis on the most predominant variability ranges of the social housing stock of southern Spain (Andalusia) is carried out. Efforts are focused on the building characterisation of the linear block typology. To do so, an extensive database, which contains information on slightly under 39,500 social dwellings, is analysed. The conclusions reported in this study may be implemented into the construction of real case building archetypes through bottom-up building stock modelling techniques with the objective of assessing the real energy and thermal performance of the existing stock, providing useful information for public stakeholders.

Seismic assessment of the XX century masonry buildings in Florence: Vulnerability insights based on urban data acquisition and nonlinear static analysis

This paper deals with the seismic vulnerability assessment of modern masonry buildings in Florence, Italy. The work focuses on the XX century masonry structures realized before seismic codes. The research is divided into two main distinct phases: i) the acquisition of the main geometrical and structural information at the urban scale; ii) the selection of a representative model to execute an analytical assessment. The first part of the work represents a cognitive phase based on archive research and the collection of the buildings, which allowed the architectural and structural identification of over 300 structures. The second part of the work represents an analytical phase targeted at deriving fragility curves. A real case study representative of the simple block typology with two apartments per floor and a central stairwell has been selected and a probabilistic framework based on nonlinear static analysis has been performed. The analytical conclusions of the research point out a significant vulnerability of these structures, mainly ruled by a weak-piers-strong-spandrels behaviour. For the Life Safety limit state (SLV), around 40% of probability to having DL4 and 40% reaching DL5 are expected. The paper presents the results in terms of generic outcomes providing indications useful for the uncertainty's treatment and the engineering practice.

Influence of urban form on air quality: The combined effect of block typology and urban planning indices on city breathability

Urban morphology affects airflow, causing pollutant accumulation within the urban canopy. Urban planning can regulate urban form by applying such strategies as defining urban block typology and stipulating urban indices. Consequently, urban planning can contribute to a healthy environment. In this context, modeling pollutant dispersion can assist urban planning decisions. Nonetheless, there is a lack of studies investigating the combined impact of urban block typology and urban indices on air quality. Therefore, this study aims to analyze the impact of these combined strategies on pollutant dispersion. Using computational fluid dynamics techniques, we investigated three combinations of urban indices (floor area ratio, surface coverage, and height) for three urban block typologies (single-block, detached building, and central courtyard). A total of nine urban configurations were distributed into three sets of urban index values for the three block typologies, namely “basic cases,” “1-cases,” and “2-cases.” We used the Unsteady Reynolds-Averaged Navier–Stokes equations and the κ–ω SST turbulence model for the numerical simulations. The validation was conducted using wind tunnel experimental data. To assess city breathability at pedestrian height we used five parameters: pollutant concentration, the mean age of air, net escape velocity, and pollutant mass fluxes. The results showed that both strategies (i.e., block typology and urban indices) affect urban air quality. However, the performance of a block typology depends on the urban index values. For instance, in the “2-cases,” decreasing the surface coverage by increasing the building's height improved ventilation efficiency in all typologies. Nonetheless, this strategy changed the performance ranking of the “basic cases.” In “basic cases” the single-block typology had the best performance; in the “2-cases,” the courtyard typology performed best. Although the courtyard typology improved air quality inside the patio, the outdoor areas displayed more pollutant concentration. Finally, general orientations to developing urban planning strategies were formulated.

Investigation of typical residential block typologies and their impact on pedestrian-level microclimate in summers in Nanjing, China

The morphology of urban residential blocks in China, which is strictly affected by regulations, can potentially improve or deteriorate microclimates. This paper first proposes a framework for identifying typical residential block typologies using Nanjing as an example. A thorough investigation, consisting of 114 samples, was conducted, and 18 typical residential block typologies were summarized. Second, 3D non-isothermal numerical simulations were performed on the hottest days of summer using the ENVI-met. The effect of morphological indices on the microclimate at the pedestrian level was explored using statistical methods and a novel graphic method named m-SpaceMate. The results revealed a strong correlation between the urban heat island intensity (UHII), mean radiation temperature, and universal thermal climate index (UTCI) and floor area ratio (FAR), as well as between wind velocity (U) and building coverage ratio (BCR). A significant increase in FAR (by approximately 1.0) can result in a low UTCI that was driven by MRT and shading conditions. Six-floor blocks, with FAR between 1.8 and 2.1, had a better overall thermal environment (except for lower U) than that of 11-floor blocks. When considering a similar BCR, blocks with slab-type buildings tended to have a U that was higher by approximately 30%.

Retrofitting for Improving Energy Efficiency: The Embodied Energy Relevance for Buildings’ Thermal Insulation

Abstract Envelope insulation is a well-known strategy to improve buildings’ energy efficiency. This paper considers two archetypes of an apartment block typology largely diffused in the Italian building stock and evaluates the energy savings resulting from the application of three insulation materials: polyurethane foam, rock wool, and resin bonded fibre-board. The energy requirements for winter heating and summer cooling are assessed with EnergyPlus and then compared to the embodied energy of the insulation materials. Hence, the energy and carbon paybacks are calculated, and a cost analysis is proposed to provide an insight into the market impact for the retrofit materials’ choice. The apartment block model is analyzed in three main cities (Rome, Milan, and Palermo) allowing to assess the impact of the climatic condition in terms of minimization of primary energy consumption and environmental emissions. Simulations showed that thermal insulation has a higher impact on winter heating and slightly affects the summer cooling requirement. In Milan, the refurbishment gains relevance as the energy and carbon payback periods are shorter than those of the city of Palermo characterized by warmer weather. Considering the embodied energy impact, this method allows us to estimate the maximum potential for energy savings in existing buildings and provides an estimation of achievable results in a short-medium period.

Impact of Urban Block Typology on Microclimate Performance in a Hot-Humid High-Density City

Because of their structure, urban areas induce very complex climate phenomena while notably impacting pedestrian safety and comfort in the urban microclimate. This paper presents the results of an investigation into the influence of urban block typology and building intensity on environmental performance in the context of the urban microclimate of a hot-humid high-density city. Qualitative and quantitative characterization of the building geometries used in this study was conducted to compare an existing block typology scenario with five new block typology scenarios in an area of 350 x 350 x 150 (L x W x H) meters. The scenarios investigated were composed of different settings for floor area ratio (FAR) and building coverage ratio (BCR) and different configurations of building elements (tower, podium, and courtyard). They were simulated and analyzed using the ENVI-met software. The simulation results indicate that the five new scenarios all improved the environmental thermal parameters and that the FAR has a greater influence than the BCR. FAR has the strongest correlation with air temperature, followed by solar radiation and relative humidity. The influence of BCR on humidity and wind speed is not as significant as that of FAR. A tower strongly influences wind speed in proportion to the height of the building. Open courtyards correlate with higher temperature and lower humidity than closed courtyards. The combination of a closed courtyard with a hybrid block consistently outperformed the other configurations in thermal performance. Within this framework, the proposed scenarios can provide recommendations for city design regulations and input for urban design methods to further improve microclimate performance.

Atmospheric dispersion and urban planning: An interdisciplinary approach to city modeling

Geometry modeling is a common approach in pollutant dispersion studies. Block typology is a key element for representing geometries closer to real city environments. However, urban pollutant modeling studies and urban planning processes have different approaches regarding block typology and applied metrics. Therefore, the objective of this work is to compare urban block typologies and urban metrics used in literature studies with those found in real cities. The methodology combined a literature review with an empirical analysis of sample areas in selected cities. The results showed that more than 50 % of the studies applied idealized building arrays. Nonetheless, the idealized array tends to underestimate real densities, often misrepresenting urban planning indices. On the other hand, derived geometry reduces modeling complexity and increases the applicability of studies in urban planning. Based on our findings, we suggest an urban block parameterization derived from real urban areas (representative of the densest cities in Asia, Europe, and America). This study selects five block typologies derived from actual cities (single block, detached buildings, courtyard, inner courtyards, and row buildings) with estimated values of the floor area ratio (FAR) and surface coverage (SC) that, when combined, provide a more precise representation of density.

The impact of urban block typology on pollutant dispersion

Block typology is a central component for urban planning and a key element to represent the urban form, which affects the airflow. Therefore, the aim of this work consists of investigating the impact of different urban block typologies in urban pollutant dispersion. Five typologies derived from real cities were investigated using the computational fluid dynamics technique: single-block, detached buildings, central courtyard, inner courtyards, and row. The numerical simulations were performed using URANS (Unsteady Reynolds-Averaged Navier-Stokes) equations and the κ−ω SST model to represent the turbulence effects. The model was validated using wind tunnel experimental data. Urban air quality was assessed using five parameters: mean age of air, net escape velocity, pollutant concentration at pedestrian level, and pollutant mass fluxes towards the urban canopy and outwards from it. The results showed that the single-block typology revealed an average pollutant concentration at pedestrian height 80% lower than that estimated in the detached building typology, which presented the highest concentration, probably due to the highest aspect ratio associated with permeable facades. Further, the higher the wind velocity, the lower the mean age of air. Finally, the unbuilt areas’ disposition within the block proved to be the more important parameter influencing the pollutant dispersion.

A parametric method using vernacular urban block typologies for investigating interactions between solar energy use and urban design

Building geometries strongly constrain the on-site solar energy use. In this work, solar energy use is measured by solar energy penetration and capital costs for the photovoltaic panel installations. This work provides a novel typological method for investigating interactions between solar energy use and urban design. Compared to other studies using typological methods, this work uses a typological method that highlights both computational efficiency and relevance to the vernacular contexts. Typical vernacular block typologies are formulated using a case study of built urban form featuring various combinations of block dimensions, building patterns, floor area ratios, and site coverage. We develop the Urban Block Generator, a tool to parametrically model such block typologies in Rhino/Grasshopper. We assess the solar energy penetration and the capital costs for these block typologies using the Urban Block Generator and the City Energy Analyst, an urban energy modeling and simulation program. We demonstrate this workflow on a case study in Singapore formulating 18 vernacular block typologies. The results are discussed and interpreted into urban design options and suggestions on various urban design parameters for different main driving forces, either maximizing the solar energy use or achieving a certain floor area ratio.

A method of calculating urban-scale solar potential by evaluating and quantifying the relationship between urban block typology and occlusion coefficient: A case study of Wuhan in Central China

Relevant research shows that the potential of solar energy utilization varies greatly in different occlusion conditions. However, existing methods of assessing macro-city-scale solar roof utilization potential are not capable of considering the factor of mutual occlusion between urban buildings. To measure the overall solar photovoltaic utilization potential of the city, it is necessary to quantify the occlusion caused by the urban environmental building roof. This paper uses typical high-density blocks to quantify differences of occlusions on the building roof caused by urban blocks and building functions. Taking Wuhan as an example, a large number of urban blocks which form indicators were counted were selected as research samples, the data sets covers six types of morphological indicators to classify the urban blocks, and then the above blocks was modelled to simulate the solar radiation in order to obtain the values and combine with their morphological parameters, which will help to get roof solar occlusion factors by linear regression ways. The overall roof occlusion coefficient result of Wuhan is 0.079. By applying the above-mentioned occlusion coefficient to measure the solar energy potential of Hongshan District in Wuhan, the annual photovoltaic power generation was calculated to be able to reach 168.02GWh.

Beyond nearly zero energy urban design: A holistic microclimatic energy and environmental quality evaluation workflow

Despite the urgent global call for an energy transition and the promotion of health and well-being in cities, a holistic approach to evaluating the trade-offs between an urban energy balance and environmental quality considerations is lacking. This paper bridges this gap by introducing a Grasshopper digital workflow through which the impacts of a wide range of building and urban design parameters on both energy performance and environmental quality can be effectively evaluated. This workflow is tested here for both theoretical and site-specific urban test cases in the context of Tel Aviv. For these test cases, the performance metrics - energy load match, spatial daylight autonomy and universal thermal climate index - were calculated using EnergyPlus, Radiance and ENVI-met simulation engines for different block typologies and were then analyzed. The results showed that among the block typologies, the courtyard achieved the optimal combination across the tested environmental criteria, despite the daylight and energy generation penalty associated with self-shading in compact block typologies. This workflow highlights the performative tradeoffs between energy and environmental quality considerations and can thus help urban designers achieve not only a lower environmental impact but also regenerative and healthier design outcomes.

Synergetic urban microclimate and energy simulation parametric workflow

Although the interrelations between urban microclimates and energy demand have been acknowledged, few workflows integrate microclimatic boundary conditions to predict energy demand in parametric morphological studies. This paper helps bridge this gap by introducing a novel workflow which brings together energy and microclimatic modelling for a synergetic assessment at the block scale. The interrelation between form, energy and urban microclimatic conditions is explored here in the climatic context of Tel Aviv by coupling Envimet and EnergyPlus. The potential of this coupling is explored in three different block typologies, each tested for four different density scenarios focusing on the cooling demand on a typical hot day. Results show the substantial increase of as high as 50% in cooling demand when the microclimatic weather data is taken into account and indicate the potential to capitalize on new computational tools which allow to quantify the interrelations between urban form, microclimate and energy performance more accurately.

Evaluation of photovoltaic potential by urban block typology: A case study of Wuhan, China

Due to the ever increasing energy demand, PV utilisation in the urban scale has become an attractive solution. The purpose of this paper is to demonstrate the effect of urban block type on solar potential. There exists a requirement to analyse solar potential in the real urban context of Wuhan based on block function and type. Therefore, this paper studies a real case in Wuhan’s urban context by selecting 15 cases of real urban industrial, commercial and residential blocks. The PV output was calculated for roofs and facades respectively. The results obtained showed obvious differences between the three type of blocks, where commercial blocks received the most total solar irradiation, followed by residential blocks, and then industrial blocks. Similarly, the distribution of solar irradiation on roofs and facades for each block was vividly different based on the block type, owing to differences in building forms based on block function.