Zero-carbon City Research Articles

The Feasibility of Flexible and Adaptive Green Certification in Accelerating Zero Carbon Cities

The Feasibility of Flexible and Adaptive Green Certification in Accelerating Zero Carbon Cities

Towards zero-carbon cities: how does environmental information disclosure impact the risk of carbon locking?

Utilizing panel data from 119 cities spanning from 2013 to 2019, the study rigorously investigates the influence of environmental information disclosure (EID) on mitigating the risk of urban carbon lock-in through the application of both two-way fixed effects and spatial econometric models. The findings robustly indicate that EID plays a significant role in facilitating carbon unlocking within cities, a conclusion that remains steadfast even after addressing potential endogeneity issues. Mechanistically, it is revealed that EID can effectively decrease the risk of carbon lock-in by enhancing urbanization levels and reducing energy intensity. Furthermore, the study unveils that the efficacy of EID in curbing urban carbon lock-in risk is also contingent upon factors such as carbon intensity, population size, and environmental quality, highlighting the multifaceted nature of EID's impact on urban carbon management. Specifically, the increase in carbon intensity, the expansion of population size, and the deterioration of environmental quality will reduce the carbon unlocking effect, which may not be conducive to the achievement of the goal of "carbon neutrality" in cities. The spatial effect test found that EID and carbon locking risk are both spatially significant positive autocorrelation, the deepening of local EID can significantly cut the risk of carbon locking in neighboring cities, and the urbanization pathway and energy saving pathway exist both locally and in neighboring places.

Preface

The 5th International Conference on Global Issue for infrastructure, environment & socio-economic development (IC-GIESED 2022) was held in Makassar, Indonesia on November 23 - 24, 2022. IC-GIESED 2022 is dedicated to address issues related to Green and Sustainable Environment Towards Net Zero Carbon Cities, hosted by Post Graduate School of Hasanuddin University and Publication Management Unit (PMU), Hasanuddin University.Environmental scientists utilize the physical footprint as a quantitative calculation tool to determine how much natural resources are used by people on a daily basis. Climate disasters, economic losses, and an increase in global temperature are all effects of carbon emissions. Urban regions have a significant potential to lower carbon emissions because they will likely house around 56% of the world’s population by 2020 and will rise to 66% by 2050. According to their pledge under the Paris Agreement, industrialized nations must attain net-zero emissions or zero carbon emissions by 2050, by bringing together researchers, scientists, practitioners and scholars in the respected fields. Professors from Saudi Arabia and Australia are invited to deliver keynote speeches, together with invited speakers from United Kingdom, Malaysia, Australia and Indonesia. Their presence indicates the concern and role of the researchers, scientists and practitioners which are significant in keeping Global Issue for infrastructure, environment & socio-economic development.This proceeding present selected papers submitted to the conference by academics and researches from universities and research institutes. All papers were subjected to rigorous peer-reviews by conference committee members and international reviewers to ensure their compliance to meet the required standard for qualified scientific publication. This volume presents recent researches in the field of Global Issue for infrastructure, environment & socio-economic development covering various related areas: climate changes and earth resources, environment, infrastructure, innovation and renewable energy and waste managementWe would like to appreciate all authors who have contributed to this proceeding, the conference committee, speakers, attendees, organizing committee and sponsors who have made the 5th GIESED 2022 a success. We wish the conference will have significant contribution in field of global issue for infrastructure, environment & socio-economic development. We are also expecting that this conference proceeding contributes in looking at a new paradigm for global Issue for infrastructure, environment & socio-economic development.Baharuddin HamzahChair of Organizing Committee GIESED 2022.Hasanuddin University

University-Campus-Based Zero-Carbon Action Plans for Accelerating the Zero-Carbon City Transition

After three decades of global climate initiatives, local governments’ capabilities to implement policies and solutions have not always been effective in making the urban environment more resilient and adaptive to climate change. All the previous climatic initiatives and decisions were mostly carried out by governments or affiliated actors on global or regional scales. However, the lack of notable climate actions at the community level is evident in the current crisis of urban sustainability. To drive a radical change toward a zero-carbon transition at the city scale, massive decarbonization is required at the institutional level (academic/nonacademic campus) of a city. Among all the nongovernmental actors, it is always expected that Higher Education Institutes (HEIs) would take the lead in promoting a resilient and sustainable future for the cities through their education, research, and innovation. HEIs’ multidimensional activity resembles the “small scale model of a city” interacting with different subsystems like education, administration, transport, housing, health, etc. However, the present studies were found to be mostly based on specific regions and developed countries. In addition, the previously developed methods of assessing energy consumption and CO2 emissions at the university level lack adaptability for other countries and urban settings. Following the need for a comprehensive method of evaluating energy consumption and accelerating the zero-carbon practice to a broader scale, a new framework is proposed here for a university campus. It can be implemented regardless of the campus type and geographic and weather conditions. After implementing the evaluation methods on a 753-acre campus of Rajshahi University, the campus typology and natural resources were identified. Following that, the behavior patterns of the users in terms of energy usage and waste generation were also determined. Finally, the results show that 1900.71 tons of CO2 was emitted in the academic year 2022. The per-capita CO2 emission was 0.041 tons of CO2. To boost the zero-carbon city transition, three core parameters of scaling-up methods were taken into consideration to evaluate the benefits of zero-carbon campuses. The scalability of the zero-carbon practices was evaluated based on the ideas of (1) expansion—how educating future generations about the environment can have a long-lasting impact, (2) demonstration—adopting innovative practical and technological solutions to exhibit the benefits of zero-carbon practices to society, and (3) collaboration—building strong alliances with state and nonstate actors of the city to promote sustainability through sharing knowledge, innovation, and technology.

Intuitionistic fuzzy gained and lost dominance score based on symmetric point criterion to prioritize zero-carbon measures for sustainable urban transportation

PurposeAchieving a zero-carbon city requires a long-term strategic perspective. The authors propose a decision-making model which would take into account the economic, environmental and social impacts for prioritizing the zero-carbon measures for sustainable urban transportation.Design/methodology/approachAn integrated intuitionistic fuzzy gained and lost dominance score (IF-GLDS) model is introduced based on intuitionistic fuzzy Yager weighted aggregation (IFYWA) operators and proposed weight-determining IF-SPC procedure. In addition, a weighting tool is presented to obtain the weights of decision experts. Further, the feasibility and efficacy of developed IF-SPC-GLDS model is implemented on a multi-criteria investment company selection problem under IFS context.FindingsThe results of the developed model, “introducing zero-emission zones” should be considered as the first measure to implement. The preference of this initiative offers sustainable transport in India to achieve a zero-carbon transport by having the greatest impact on the modal shift from cars to sustainable mobility modes with a lower operational and implementation cost as well as having greater public support. The developed model utilized can be relocated to other smart cities which aim to achieve a zero-carbon transport. Sensitivity and comparative analyses are discussed to reveal the robustness of obtained result. The outcomes show the feasibility of the developed methodology which yields second company as the suitable choice, when compared to and validated using the other MCDA methods from the literature, including TOPSIS, COPRAS, WASPAS and CoCoSo with intuitionistic fuzzy information.Originality/valueA new intuitionistic fuzzy symmetry point of criterion (IF-SPC) approach is presented to find weights of criteria under IFSs setting. Then, an IF-GLDS model is introduced using IFYWA operators to rank the options in the realistic multi-criteria decision analysis (MCDA) procedure. For this purpose, the IFYWA operators and their properties are developed to combine the IFNs. These operators can offer a flexible way to deal with the realistic MCDA problems with IFS context.

빅데이터를 이용한 서울시 주거용 건물에너지 소비 실증 분석

On the path to a zero-carbon city, reducing residential energy consumption - the largest contributor to city greenhouse gas emissions - is critical. This study examines the impacts of building characteristics and temperature on residential electricity and gas consumption in Seoul. This study utilized two large datasets: building-level energy consumption data and microclimate data from 1,100 sensors throughout Seoul to reflect perceived building temperatures. Results show that electricity use follows a well-known U-shape relationship with temperature, with a 1°C change in summer or winter leading to a 3 ~ 4% increase in electricity use. Gas consumption for heating, on the other hand, is highest at extremely low temperatures, with a 1°C decrease in winter leading to a 3% increase. Furthermore, electricity consumption is associated with land price, with higher economic levels resulting in more electricity use. These findings underscore the importance of efficient demand-side electricity management as Seoul faces increasing electricity demand due to rising temperatures and growing economic levels.

Delivering Tram-Based Boulevards: Learning from Opportunities and Challenges in Three European City Case Studies

Increasing calls for zero-carbon cities invite transformative solutions for people and places within our cities around the world. Key to the transformation is cities and regions shifting in mobility away from fossil-fuel based car-oriented solutions. The paper investigates a range of case studies where “tram-based boulevards” have been planned or implemented to provide such opportunities. The case studies share a common broader policy objective: to transform the car-oriented or car-saturated areas to an intensified urban template based on a critical presence of dedicated mid-tier transit infrastructure and active transport. “Trams”, or mid-tier, mid-capacity transit when combined with Transit oriented development (TOD) along whole corridors can provide transformative pathways towards zero-carbon outcomes as well as multiple, strong urban benefits. However, many successful or instructive examples of this practice from non-English speaking countries, particularly in Europe, are underdocumented in the international literature. The paper addresses this gap by investigating opportunities and challenges evident in a range of European case studies. These are explored for insight towards policy learning particularly in New World cities seeking to transform into a zero-carbon and more transit-oriented template: How can decision-makers avoid repeating the identified pitfalls, and instead focus on emulating the successful approaches and outcomes? We conclude the need for recognition of the inherent synergies between transport and land use settings in any endeavour, and their translation into policy priorities in both fields of planning. We also conclude the importance of decision makers proactively identifying and critically appraising specific opportunities for change, concerning funding, technology, public opinion, stakeholder alliances or market dynamics, and capitalising on them at suitable moments in time.

Decomposition and decoupling analysis of carbon footprint pressure in China's cities

Carbon emission reduction and carbon sequestration are the two key paths to achieve the goal of carbon neutrality. Most of the existing literature focuses on carbon emissions, often ignoring the importance of vegetation carbon sequestration. In this study, a carbon footprint pressure (CFP) index that considers both carbon reduction and carbon sequestration was developed, and the driving factors and decoupling state of China's urban CFP were studied using index decomposition analysis and the Tapio decoupling model. High precision environmental indicators obtained by remote sensing satellites were used to estimate carbon emissions and carbon sequestration data for individual cities. The results show that China's CFP generally had an upward trend from 2000 to 2017, with economic growth and population size being the main drivers for this increase. Additionally, technological progress can effectively alleviate CFP. Only 12.77% of Chinese cities have achieved the decoupling of carbon sequestration from carbon emissions; these are mainly economically underdeveloped cities. Most economically developed cities have been under great pressure to become net zero carbon cities. These cities should pay attention to improving the carbon sequestration capacity of vegetation while reducing carbon emissions.

Improving residential building energy simulations through occupancy data derived from commercial off-the-shelf Wi-Fi sensing technology

One of the main required actions for moving forward in zero-carbon cities’ mission is to increase building energy efficiency. Building energy simulations are key tools for HVAC control, building energy management, testing different building energy efficiency scenarios, and providing feedback to the occupants. Unfortunately, these tools have a significant weakness in occupant behavior modeling and prediction. Several recent studies used different occupancy measurements and methods to predict occupant behavior. However, they suffer from threatening the occupant's privacy and the high cost of their infrastructure and deployment. This paper aims to leverage passive WiFi sensing methods for occupant behavior estimation using commercial off-the-shelf WiFi devices, for which the infrastructure is already available in many buildings. Passive and device-free WiFi sensing does not threaten the occupant's privacy, and its deployment cost is low. Therefore, this method of occupancy measurement has the potential to be used on an urban scale and to play an essential role in zero carbon and smart cities in the future.Different machine learning algorithms have been applied to the collected, denoised, and preprocessed Channel State Information (CSI) data to estimate the occupant behavior. Five schedules of occupancy, occupant activity, lighting, electrical equipment usage, and thermostat set point temperature could be extracted and estimated from CSI data. In the last step, all estimated schedules were fed into EnergyPlus, an energy simulation software, along with other required data for accurate energy demand calculation to estimate heating and cooling demand, which can be used for HVAC control and occupancy feedback.

Zero-Carbon Communities: Research Hotspots, Evolution, and Prospects

Global warming is a worldwide concern, with buildings generating more than 40% of the annual global CO2 emissions. A commonly accepted system of global standards for zero-carbon buildings and communities has not yet been established. In this research, the development history, hotspots, and trends at the urban scale with theoretical and data support are summarized based on the Web of Science (WoS) Core Collection. The review contains works from 1997 to 2022. A total of 19,014 papers were collected, with an overall increasing trend in the number of articles with specific keywords. The scope of the research is broad, covering the environment, sciences, ecology, chemistry, material science, physics, meteorology, atmospheric sciences, and so on. The hotspots in the low-carbon community (LCC) and zero-carbon community (ZCC) involve a wide range of disciplines, and collaborative research between related disciplines should be strengthened to propose practical solutions for the development of zero-carbon cities. The establishment of the ZCC mainly focuses on a zero-carbon-emission construction and zero-carbon operations. This research found approaches such as the choices of building construction and material, a waste recycling system, a regenerating energy system, transportation, and an examination of the community composition to realize the ZCC. In the literature it is presented that the difficulties in the construction of the ZCC are due to the lack of research in practice, operation, and subsequent maintenance. Moreover, other scholars can deepen the research on the hotspots of ZCC.

Research and Industry News

A step toward laser fusion / Mapping methane / Imaging vision’s chemistry / COVID-19 breathalyzer / Optical trapping near absolute zero / Toward zero-carbon cities / Singapore quantum network / Gender bias in labs / Photon recycling

Qualitative risk analysis of the overhead hydrogen piping at the conceptual process design stage

Namie, which is a town in Fukushima prefecture in Japan, has started a green innovation project using hydrogen to eliminate CO 2 release by 2050 and establish a zero-carbon city. One idea is to develop an overhead hydrogen piping, which is a low-pressure hydrogen supply system, in public spaces. To develop and implement the piping in Namie and other areas, it is important to both develop the process and perform the risk analysis during a preliminary process design stage. The purpose of this study was to qualitatively analyze and identify the critical risks and effective safety measures for the piping. A total of 183 accidental scenarios were identified by using a hazard identification study, and the preventive and mitigation safety measures were summarized. Hydrogen dispersion simulations revealed that low-pressure hydrogen dispersion leaking from small holes and fractured piping in public spaces could result in concerning risks depending on the leak size, direction, position, obstacles, and ignition source. In addition, a shutdown system of the piping was evaluated with a multiphysics modeling simulation, and its importance was discussed to proceed with detailed investigations. Finally, we suggested risk reduction measures based on the concept of inherent safety for the development of low-pressure hydrogen systems, and the findings can be applied to cases such as Namie. • The overhead hydrogen piping was developed. • Qualitative risk assessment using hazard identification study was carried out. • 183 accidental scenarios were identified, and safety measures were summarized. • The flammable concentration of hydrogen was predicted by dispersion simulations. • A piping shutdown valve was evaluated as a critical safety measure.

Methodology for Sustainable Development of Eco and Zero-Carbon Cities

Methodology for Sustainable Development of Eco and Zero-Carbon Cities

Developing Resilience to Emergencies: Evaluation of Thermal Indices and Outdoor Comfort Before and During the COVID-19 Pandemic

This research discusses thermal indices and outdoor comfort before and during the Coronavirus Disease of 2019 (COVID-19) pandemic in three counties in Connecticut (41.6032°N, 73.0877°W), United States. The counties are Fairfield, Hartford, and New Haven. Existing research noted that people residing in highly populated urban and low-income areas are disproportionately affected by the pandemic and subject to health, heat, and cold stress-related problems. As a result, the study is motivated to examine outdoor comfort and thermal indices in the counties that account for over 75% of the population in the state. The specific aim of the study is to examine outdoor comfort and thermal indices a year before and during the pandemic to determine if the pandemic significantly affects outdoor occupants and their overall well-being. Due to lesser activities observed during the pandemic than before the pandemic, the research questions include 1) Does the pandemic year provide a more comfortable thermal environment for outdoor occupants than the period before the pandemic? 2) Does the period provide a cleaner environment with no thermal or cold stress to occupants than before the pandemic? The research approaches include the field data recorded in 2019 and 2020. The research also utilized observations and mathematical models. The findings revealed that the mean monthly temperatures varied from −3.2°C to 25.2°C and relative humidity ranged from and 62.6–70.7%. The study revealed cold stress in wintertime, especially in Fairfield. Heat stress is also noted in summertime across the counties. New Haven is more prone to heat stress than other counties because of some factors (such as climate change, lesser land area, higher incidence from solar radiation, etc.). Higher thermal indices are reported in 2020 (during the pandemic) than the indices computed for 2019 (pre-pandemic) which could influence thermal comfort, health, and well-being of people. The indices are strongly influenced by outdoor temperatures and dew-point. A combination of some environmental variables such as temperature and wind speed also have significant effects on the indices. The study recommends that the use of clean energy for running infrastructure systems would help in mitigating the impact of climate change in various locations. The investigation suggests that a thorough evaluation of environmental conditions and interventions should be explored for developing resilience to emergencies in cities and urban areas. The research outcomes provide useful information for designers, planners, stakeholders, policymakers, etc., to develop pathways for achieving resilient zero-carbon cities in various places.

A Novel Methodology for Prioritizing Zero-Carbon Measures for Sustainable Transport

Achieving a zero-carbon city requires a long-term strategic perspective. Transport emissions are a major source of carbon emissions, and cities grapple with reducing carbon emissions, and improving the air quality for their citizens. London's new transport strategy document, called Mayor's Transport Strategy 2018, aims to achieve a zero-carbon city by 2050 and set out many actions to facilitate this transition. However, London needs a prioritisation framework which would take into account the financial, environmental and social impacts of these actions. Considering the uncertainties around these actions, which has been now significantly more crucial during the COVID-19 pandemic, this study proposes a novel extension of Best-Worst Method (BWM) and extension of the TODIM (an acronym in Portuguese for Iterative Multi-Criteria Decision Making (MCDM)) method using D numbers. This TODIM-D based fuzzy MCDM approach provides a prioritisation framework for the actions associated with zero-carbon city policies set out in London's strategy document. According to the results of the proposed method, “introducing zero-emission zones” should be selected as the first initiative to implement. The prioritization of this initiative allows London to achieve a zero-carbon transport by having the greatest impact on the modal shift from cars to sustainable mobility modes with a lower operational and implementation cost as well as having greater public support. The proposed method used in this study can be transferred to other cities which aim to achieve a zero-carbon transport.

Estimation of Municipalities’ CO2 Emissions for Realization of the “Zero Carbon Cities” considering the Amount of Renewable Energy and the Forest Absorption

Estimation of Municipalities’ CO₂ Emissions for Realization of the “Zero Carbon Cities” considering the Amount of Renewable Energy and the Forest Absorption

Impact of Urban Expansion and In Situ Greenery on Community-Wide Carbon Emissions: Method Development and Insights from 11 US Cities.

Biogenic CO2 emissions in cities are shaped by urban land cover change which can release carbon stocks, and, carbon sequestration by in situ vegetation. To date, these two processes have not been studied together and compared with transboundary fossil fuel-based CO2 emissions of urban energy use. We leverage remote sensing and machine learning to quantify biogenic CO2 emissions between 2006 and 2012, across 11 U.S cities, including central and suburban cities, in different climate zones. Results indicate that in situ carbon sequestration by greenery varied moderately across cities (-2.1 to -0.87 Mg CO2 ha-1 yr-1), while emissions from the carbon stock change due to land conversion varied much more (-3.4 to 9.8 Mg CO2 ha-1 yr-1), indicating that the latter dominates biogenic CO2 emissions. Net biogenic CO2 emissions were negative (carbon sink) in four cities, while large net positive emissions were present in rapidly growing suburbs. As a ratio of community-wide energy use for travel and buildings, biogenic CO2 emissions were a small proportion in the core cities Denver (0.17%) and Minneapolis (0.33%) and as high as 38.2% in growing exurban communities. These results show that land cover change and greenery will be important policy levers in zero-carbon city planning.

SMART ZERO CARBON CITY: KEY FACTORS TOWARDS SMART URBAN DECARBONIZATION

Fossil fuels-based human activity over time has generated unacceptable local levels of air pollution and GHG emissions. One of main implications of this activity is Climate Change, which unforeseen consequences are already impacting at local and global scales. This research is focused on defining an effective framework to shift that trend in the local level through the implementation of the Smart Zero Carbon City concept, which brings together the emerging Smart City paradigm and the 2030/2050 EU goals with the urgent need of decarbonizing our local environments. In this case, the study applies the Smart Zero Carbon City concept and implementation method into 5 EU cities, focusing on the case of Sonderborg municipality (DK) to extract the Key Factors towards Smart Urban Decarbonization, which are applicable to other cities facing this ambitious transition. Keywords: Decarbonization, Smart Zero Carbon City, Smart Cities, Energy Transition

Low carbon effects of urban underground space

Urbanization is progressing rapidly, while problems raised by climate change are occurring across the globe. Cities are at the center of both of the two tendencies therefore, low carbon or zero carbon cities are being promoted. Urban underground space (UUS) is a key component in the process of urbanization and plays a significant role in creating low carbon cities, as highlighted in this paper. Meanwhile, UUS also involves unavoidable drawbacks regarding energy consumption in terms of lighting, ventilation and dehumidification. In this paper, the advantages of UUS in creating low carbon cities are analyzed, and a framework for calculating the positive low carbon effects derived from UUS use is established. Additionally, some alleviating measures in response to the potential low carbon disadvantages of UUS are proposed. Based on the analysis, some planning and design implications for the development of urban underground space in order to fulfill its role as a contributor to urban sustainability are discussed.

SMART ZERO CARBON CITY READINESS LEVEL: INDICATORS SYSTEM FOR CITY DIAGNOSIS TOWARDS DECARBONISATION AND ITS APLICATION IN THE BASQUE COUNTRY

Nowadays urban environments concentrate more than half the world’s population, reaching up to 70% on 2050 according to forecasts. This concentration implies that most of future challenges will take place in cities as well as the opportunities coming from their potential solutions. Current technological innovation can provide support in facing one of main challenges society is facing: reducing carbon footprint from our cities. This ambitious transition, steered by the Smart Zero Carbon City (SZCC) concept, needs a flexible characterisation method, which can be adapted to different kinds of cities to evaluate the main features of each city, hence proposing and prioritising most suitable interventions. The aim of this study is focused on the characterisation of cities according to the SZCC concept through a set of indicators: the Smart Zero Carbon City Readiness Level (SZCC Readiness Level), able to analyse key aspects of cities according to SZCC concept (Characteristics of the city; City plans and strategies; Energy; Mobility; Infrastructures and ICT services; Citizen Engagement). This characterisation enlightens the development of SZCC concept in the city, identifying its strengths and weaknesses in order to ease the alternatives’ selection towards decarbonisation, being handy at a time for those small and medium-sized municipalities, so common in the European context, which usually hold less resources than big capitals to implement decision-making support diagnoses. In order to validate this set of indicators, SZCC Readiness Level has been implemented in 5 Basque cities, which represent different urban typologies, analysing its current situation regarding SZCC concept. Keywords: Smart Zero Carbon City Readiness Level, Smart Zero Carbon Cities, Decarbonisation, City diagnosis, Indicators.