Peng Du

This report is the summary of a collaborative design studio at IIT that focused on sustainable vertical cities and tall buildings in different terrains and climate zones across the world. A detailed overview of the seven studio projects can be found in the report.

This research report offers a quantitative evaluation of long-held assumptions, and with sometimes surprising results. The ground-breaking study quantitatively investigates and compares the sustainability of people’s lifestyles in both urban and suburban areas from environmental and social perspectives, using detailed information directly collected from households and best available data from public resources. It fills significant research gaps in our knowledge of the sustainability of urban… Show more

This research report offers a quantitative evaluation of long-held assumptions, and with sometimes surprising results. The ground-breaking study quantitatively investigates and compares the sustainability of people’s lifestyles in both urban and suburban areas from environmental and social perspectives, using detailed information directly collected from households and best available data from public resources. It fills significant research gaps in our knowledge of the sustainability of urban density compared to suburban sprawl. This is an indispensable resource for policy makers, developers, urban planners, architects, utilities, and anyone else with a stake in shaping the future of the built environment. Show less

The goal of this study was to investigate residents’ satisfaction with their place of residence as well as overall life in general via surveys of individuals living in existing high-rise residential buildings in downtown Chicago, IL, and in existing low-rise residential buildings in suburban Oak Park, IL. Over 1500 individuals were contacted directly, resulting in over 500 responses. The number of fully completed responses for this study was 177, including 94 from residents of four downtown… Show more

The goal of this study was to investigate residents’ satisfaction with their place of residence as well as overall life in general via surveys of individuals living in existing high-rise residential buildings in downtown Chicago, IL, and in existing low-rise residential buildings in suburban Oak Park, IL. Over 1500 individuals were contacted directly, resulting in over 500 responses. The number of fully completed responses for this study was 177, including 94 from residents of four downtown high-rise buildings and 83 from residents in suburban low-rise homes. Residents living in downtown high-rise buildings had significantly higher life satisfaction scores than residents living in suburban low-rise homes when controlling for demographic differences; however, the differences were small, as housing type explained less than 5% of the observed variance in life satisfaction outcomes. The research also evaluated five life satisfaction domains including travel, accessibility, social interaction, safety, and overall residential environment (ORE). In all cases, residents of the downtown high-rises reported higher satisfaction levels, although the scores on all these five satisfaction domains reported from both urban scenarios were very high. Moreover, all five satisfaction domains were highly associated with each other, and accessibility and safety were found as the strongest predictors of ORE for individuals. Show less

It is widely accepted that the concentration of people living in high-density city centers offers greater operational energy efficiency and lower greenhouse gas emissions than lower-density expanded suburbs. The prevailing assumption is that lower-density suburbs are dominated by larger low-rise buildings that have higher building energy use requirements and greater per-person automobile travel requirements than high-density city centers dominated by medium- and high-rise buildings located in… Show more

It is widely accepted that the concentration of people living in high-density city centers offers greater operational energy efficiency and lower greenhouse gas emissions than lower-density expanded suburbs. The prevailing assumption is that lower-density suburbs are dominated by larger low-rise buildings that have higher building energy use requirements and greater per-person automobile travel requirements than high-density city centers dominated by medium- and high-rise buildings located in close proximity to a variety of public transit systems. However, very few studies to date have utilized empirical data at an individual household scale to evaluate differences in the operational energy (OE) footprints for both building and transportation energy end-uses between high-rise urban and low-rise suburban households. Therefore, this work collects empirical data on building and transportation OE consumption by individuals and households living in two economically similar groups: existing high-rise residential buildings in downtown Chicago, IL, USA and existing low-rise residential buildings in suburban Oak Park, IL, USA. Data were collected from over 500 households via an online survey. We considered the following components of residential living: (1) building OE (BOE), which includes electricity and/or natural gas use for all building energy end-uses; and (2) transportation OE (TOE), which includes the OE for multiple modes of transportation (i.e., automobile, bus, subway, regional train, etc.) based on average travel behavior in each location, as well as the OE for supporting transportation infrastructure. We estimate that downtown high-rise living in this sample of residences in Chicago, IL accounts for approximately 427 GJ of primary OE per household per year, on average, which was 14% lower than the average for suburban low-rise living in the Oak Park, IL homes (499 GJ per household per year). Show less

This paper reviews the 2014 Network 3D High-Rise Design Studio, which was undertaken by the College of Architecture and Urban Planning (CAUP), Tongji University, with assistance from the CTBUH and Kohn Pedersen Fox Associates (KPF). The project site is located in Manhattan, New York City, one of the densest urban areas in the world. The studio was intended to explore what the three-dimensionality of cities means for tall buildings and their ability to locate extremely dense development atop… Show more

This paper reviews the 2014 Network 3D High-Rise Design Studio, which was undertaken by the College of Architecture and Urban Planning (CAUP), Tongji University, with assistance from the CTBUH and Kohn Pedersen Fox Associates (KPF). The project site is located in Manhattan, New York City, one of the densest urban areas in the world. The studio was intended to explore what the three-dimensionality of cities means for tall buildings and their ability to locate extremely dense development atop major urban infrastructure, while also providing quality public space. Show less

It is commonly accepted that the concentration of people in high-density urban city centers, which are typically dominated by medium- and high-rise buildings located close to public transit systems, offers greater overall energy efficiency and lower life-cycle greenhouse gas emissions than lower-density expanded suburbs, which are dominated by low-rise single-family buildings and larger per-person automobile travel requirements. However, few studies have combined quantitative analyses of the… Show more

It is commonly accepted that the concentration of people in high-density urban city centers, which are typically dominated by medium- and high-rise buildings located close to public transit systems, offers greater overall energy efficiency and lower life-cycle greenhouse gas emissions than lower-density expanded suburbs, which are dominated by low-rise single-family buildings and larger per-person automobile travel requirements. However, few studies have combined quantitative analyses of the life-cycle energy use of both buildings and transportation in both urban and suburban areas, especially in American cities. This work uses a variety of data sources to provide a quantitative comparison of the life-cycle energy consumption associated with residential life (including buildings, transportation, and supporting infrastructure) in prototypical downtown high-rises and suburban low-rises in and around Chicago, IL. We estimate that downtown high-rise living in Chicago, IL accounts for approximately 25% more life-cycle energy per person per year than suburban low-rise living, on average, contrary to some common beliefs (best estimates were ~141 and ~113 GJ/person/year, respectively). Building operational energy use was found to be the largest contributor of the total life-cycle energy in both the downtown high-rise and suburban low-rise cases, followed by vehicle operational energy. Show less

It is widely accepted that dense or compact city should be more “sustainable” due to higher energy efficiency in higher residential density along with greater accessibility to city facilities, and shared infrastructure. A key question of interest is the extent to which developing more compactly would reduce VMT and make alternative modes of travel (i.e., walking, bicycling, public transit, etc.) more feasible. Yet, there are very few studies that conduct a comprehensive energy and environmental… Show more

It is widely accepted that dense or compact city should be more “sustainable” due to higher energy efficiency in higher residential density along with greater accessibility to city facilities, and shared infrastructure. A key question of interest is the extent to which developing more compactly would reduce VMT and make alternative modes of travel (i.e., walking, bicycling, public transit, etc.) more feasible. Yet, there are very few studies that conduct a comprehensive energy and environmental life-cycle measure of residential mobility in different urban patterns, in terms of location, travel behavior, accessibility, etc.

The research outlined in the paper conducts a life-cycle assessment (LCA) of residential mobility within three urban scenarios in Chicago: Chicago Loop as a high dense downtown district, Oak Park as a less dense suburb close to the downtown, and Aurora as a much less dense suburb far away from the downtown. In these three cases the research quantifies and compares the life-cycle energy in resident travel through different modes of transport such as automobile, bus, CTA train, and Metra, including such LCA components as vehicle manufacturing & maintenance, vehicle operation, infrastructure construction & operation, etc. The study proves the denser area with shorter commuter distance consumes less life-cycle energy of residential mobility. Show less

A review of the CTBUH 2014 Shanghai International Conference

It is widely accepted that the concentration of people in denser cities – sharing space,
infrastructure, and facilities – offers much greater energy efficiency than the expanded
horizontal city, which requires more land usage as well as higher energy expenditure in
infrastructure and mobility. But the principal has never actually been examined at a detailed
level. Most research in this area to date has focused on the large scale-energy consumption and
populations of cities… Show more

It is widely accepted that the concentration of people in denser cities – sharing space,
infrastructure, and facilities – offers much greater energy efficiency than the expanded
horizontal city, which requires more land usage as well as higher energy expenditure in
infrastructure and mobility. But the principal has never actually been examined at a detailed
level. Most research in this area to date has focused on the large scale-energy consumption and
populations of cities, rather than communities. The Council on Tall Buildings and Urban Habitat
(CTBUH), in an attempt to investigate this, embarked on a research project in early 2014, in
conjunction with the Illinois Institute of Technology (IIT), entitled “A Study of the Sustainability
Implications of Differing Urban + Suburban Locations in Chicago,” which is focused on
demystifying the myths on both sides of the density vs. sprawl debate. This paper gives a summary of progress to date. Show less