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

Abstract

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.

1. Introduction

1.1. Transition from Global to City-Level Climate Action Plans

According to UN-Habitat, man-made activities at the city level consume around 78% of the world’s total energy and generate about 60% of greenhouse gases (GHG) globally [1]). In addition to that, even though cities around the world account for less than two percent of the Earth’s surface, the urban population is estimated to rise from 55% to 68% [2]. According to a model developed by urban environment researcher Karen Seto and her colleagues, nearly 6 million square kilometers of land have a slight possibility of becoming urban, and 1.2 million square kilometers have a high potential of becoming citified by 2030 [3]. The material consumption within their urban boundaries might increase up to 89 billion tons by 2050 as well [4]. Most importantly, among all urban sectors, transport and buildings have been identified as the dominant contributors to the carbon footprint and environmental damage [5]. This high carbon footprint is considered to be associated with poor planning and management of environmental resources, overpopulation, unplanned transport systems, inefficient energy systems, and so on [6]. Besides facing complications in their basic operations, cities also suffer from a great loss of biodiversity, resources, and ecological balance due to these anthropic activities. Even though cities carry a huge toll on global carbon emissions, they are, nevertheless, also the driving force of national and global economies.

Compared to rural areas, modern cities generate more than 80 percent of the global GDP today [7]. In search of finding a balance between economic growth, environmental impacts, and climate change, several studies, research works, and projects have been initiated through seminars, summits, and conferences in the last three decades globally. Their main purposes were objectifying climate change, the depletion of natural resources, strengthening the ecological balance, and identifying opportunities to make a more resilient and sustainable world [8]. At the very beginning, the prime agenda was specifically focused on global-scale climate change activities (see

Table 1. Notable agreements and conferences regarding global climate change and sustainability.

Year/Place	Organization/Agreement/Conference/Commitment	Mission/Agenda
1972, Stockholm	United Nations Conference on the Human Environment	Declaring education as an instrument to support a political and economic agenda.
1977, Tbilisi	The Tbilisi Declaration	Examining the critical role of “Environmental education”, which plays an important role in community development by preserving and improving the environment.
1990, France	The Talloires Declaration	Ten-point action plan for integrating environmental knowledge and sustainability into college and university operations, research, and outreach.
1992, Rio de Janeiro	UN Conference on the Environment and Development	Global collaboration to ensure “dangerous human interference with the climate system”, initially in taking control of GHG emissions in the atmosphere.
1993, Japan	The Kyoto Protocol Declaration	Global agreement of 41 countries to decrease six GHGs, focusing on the European Union’s GHG reduction to 5.2% compared to 1990.
1992, EU	The signing of the COPERNICUS University Charter for Sustainable Development	Sustainable development should be the foundation for promoting the European higher education system globally.
1993, USA	Second Nature	Determined to hasten the fight against climate change in and via higher education.
1989, Australia	Partnerships for the Sustainable Development of Cities in the APEC Region	Partnering to promote inclusive urban growth. The development of strategic infrastructure. Sharing knowledge for a future-based partnership among 21 countries to ensure economic, social, environmental, and urban governance systems’ development.
1988, UN General Assembly	The Intergovernmental Panel on Climate Change (IPCC)	Initiate knowledge sharing and discussion on the science of climate change. Analyze the social and economic impact of climate change globally and locally.
1999, Bologna	The Bologna Declaration	Education worldwide should be based on the principles of sustainable development.
2002, UN General Assembly	United Nations Decade of Education for Sustainable Development	Developing a draft international implementation program. Education for sustainable development thus became a political project, which was determined to reduce, measure, review, and report progress on emissions.
2007, Indonesia	Conference of the Parties (COP 13)	The discussion of long-term collaborative actions to advance the development goals.
2008, UK	The Climate Change Act	The Act establishes the United Kingdom as the first nation in the world with a long-term, legally binding framework to reduce carbon emissions.
2012, Rio de Janeiro	Sustainable Development Goals	A total of 17 goals with 169 targets that all 191 UN Member States have agreed to try to achieve by the year 2030.
2014, UNESCO	United Nations Decade of Education for Sustainable Development	Initiate new partnerships between the private sector and academia. Education, research, and practice align with the SDGs. Promoting, monitoring, and evaluation.
2015, Paris	The Paris Agreement	Five-year cycle for climate action globally. Graduation development of nationally determined contributions (NDCs) based on previous action plans.
2016, Ecuador	The New Urban Agenda	Intended as the global guideline for sustainable urban development for 20 years. Discussion on fundamentals for built-environment planning, development, and management. Improving urban areas based on the five core values.
2021, EU	EU Mission: Climate-Neutral and Smart Cities	Deliver 100 climate-neutral and smart cities by 2030.
2021, Glasgow	Conference of the Parties (COP 26)	Review the progress of previous global climate actions. Agreement on reaching global net zero by 2050. Encouraging an increase in climate finance globally.
2023, Nairobi	UN-Habitat Assembly (UNHA2)	Developing global guidelines regarding people-centered smart cities. Promoting the localization of the SDGs. Strengthening the collaboration of modern urbanization and climate resilience.

). Most commitments and activities were based on global collaboration and participation, where the government is the prime actor. However, these global-scale planning and measures have not been proven very efficient without involving public involvement and other stakeholder engagements [6]. These processes were incompatible with addressing the climatic and environmental issues at local and regional levels with other nongovernment actors of cities. Currently, the idea of “zero-carbon cities” has become a strong hope for a sustainable future [9]. It is anticipated that massive decarbonization is required to bring ecological balance. Decarbonization usually refers to a holistic process of behavioral–infrastructural–systemic operation change and adaptation of technologies to achieve zero or close-to-zero carbon emissions [10]. To take an active role, very recently, several cities around the world have adopted at least some changes in their functionality and operations through social innovation, technological advancement, policy development, and updated governance [11]. According to the United Nations Environment Programme (UNEP), only a synchronized approach to combining global, national, and local levels of action plans can mitigate environmental exploitation and ensure a sustainable future [4]. Urbanization and industrialization are essential parts of the development process of a region or city [12]. Efficient workforce development with high climate awareness, leadership, and uninterrupted political, technical, and financial support should become the united priority of all the governmental and nongovernmental actors to overcome the traditional barriers and trigger a paradigm [11]. As most cities’ functionalities rely on interacting with large-scale social, environmental, and infrastructural aspects, a path of transitioning to zero-carbon practices has not been identified yet [13]. Lacks of authentic data, efficient governance, and proper monitoring, as well as unfamiliarity with advanced technological features, have been proposed as the major impeding issues [11]. These factors have drawn the attention of scholars and researchers around the world who are relentlessly working towards solving these problems.

1.2. The Role of City–Campus Relationship

Traditionally, towns and cities have always been an attraction for generations of people coming to find work and other services [14]. Fast forwarding to the present times, facilities like housing, education, health care, cultural centers, and other entertainment sources have become great attractions for people to migrate to cities. Historically, higher education institutes (HEIs) have been an intrinsic part of cities around the world. As towns and cities have become the epicenter of the social, economic, and cultural development of a country, the functionality of a city has turned into a complex system. Inspired by so-called urban metabolism [15,16], comparing the city system with the human body, Gardner [17] said cities take in energy in different forms, metabolize material, and generate waste. Similarly, he also pointed out that the efficient operation of a city involves the operation of subsystems like administration, education, housing, transport, industry, health, and otherpublic–private organizations, just like the respiratory, circulatory, and other anatomical systems of the human body. All these subsystems of the city interact with each other simultaneously to function properly and provide a service to their dweller. The city–campus alliance likely has the potential to create a greater impact on city-level sustainability based on the fact that the elements of a university campus resemble the functionality of a city system. An HEI’s purpose is to equip its students, teachers, and staff with knowledge and innovation to become resilient and adapt to changes that are not only beneficial for them but also for the community [18]. Incorporating climate change curricula into higher education or activities integrating HEI campuses to promote sustainability is not a new concept. It is considered to be a well-established path toward achieving sustainable development goals [19]. Even though it started with “Environmental Education” only, society now expects practical-demonstration-based activities from HEIs. Following that, the well-recognized campus–city relationship has also turned into a strategic alliance working towards the cultural, social, and economic growth of society.

A thorough literature review was carried out based on a few factors, like the aim and objective of the research, region and context, assessment methods, and tools that were used in different studies. In addition, the innovation and limitations of the previous studies were also analyzed. As a result, it was found that most of the studies and methods were primarily focused on very specific regions. Similarly, no acknowledgment of campus-scale factors was found. Most importantly, no upscaling and downscaling factors were involved in the studies related to campus- and city-scale sustainability interchange.

Following the transition of the global- to urban-scale narrative of climate actions, it is essential to address the potential of HEIs’ operational and functional activities in terms of hampering urban sustainability. In addition, it is also necessary to evaluate the scalability of sustainable practices to accelerate the zero-carbon transition at the city scale.

We aimed to answer three questions:

• To what extent can a university campus and its multidimensional activities hamper and promote urban sustainability?
• How can the carbon emissions of an HEI campus be calculated?
• What are the potential methods to scale up HEI-based zero-carbon practices?

The gradual development of this study is as follows: Section 2, Section 3 and Section 4 demonstrates the literature analysis to find the answers to the research questions on the impact of HEIs on urban sustainability, methods of carbon emission assessment, and scalability evaluation. Section 5 illustrates the development of a new framework consisting of four steps. Section 6 initiates a discussion on the scalability factors of the framework. Following that, Section 7 explains the limitations of this study, and finally, Section 8 conclude the study with several policy recommendations.

2. The Impact of Higher Education Institutes (HEIs) on Community-Level Climate Action Plans

Over the last 50 years, an exponential growth of enrollment in tertiary-level education has been observed over the world. In 2020, the undergraduate student enrollment number was 15.9 million, combining all states in the USA [20]. Back in 2011, the South East Asian countries enrolled around 182.2 million tertiary level students, which is a significant portion of the global enrollment student number. The first idea of natural resource consumption and the depletion of those resources came to light in the 1950s [21]. The discussions were highly focused on utilizing natural resources for greater environmental and socioeconomic development. Following that, the first “Earth Summit” conference was held in Stockholm in 1972, which adopted a declaration to set up action plans to preserve and enhance the human environment globally [22]. Several global and regional conferences and agreements have been signed in the last three decades addressing global-, local-, and urban-level environment, urban sustainability, city infrastructure, transportation, public health, etc. In the early 1970s, international institutions responsible for global education, environment, and development started reviewing the role of higher education institutions in terms of promoting sustainable economic and social development nationally and globally [23]. Even though the global initiative started with “Environmental education,” in 1997, the United Nations highlighted the application of “environmental education,” which established the need for low-carbon-emission campus design and construction for the very first time [24].

The 1993 Kyoto Declaration stated that HEIs should promote sustainability by evaluating their operations and practices [25]. A gradual development of environmental concern about city-scale sustainability has initiated the idea of sustainable communities or entities inside cities. It has been highlighted in many studies how the city–campus relationship has the potential to influence changes in city environments. Over time, the importance of HEIs’ role in climate action and sustainability has been mentioned (see Table 2). Ideally, HEIs are expected to be more responsible actors in society, promoting education, equality, and innovation, reducing adverse environmental impacts, and amplifying the economic, societal, and public health benefits to society [18]. In the book Campus Ecology, Smith [26] illustrated HEIs as “microcosms” of environmental problems. He explained how different campus activities in classrooms, offices consuming high energy, and labs using hazardous chemicals and experiments can pollute water, air, and soil and how these activities have the potential to hamper the campus and its surrounding environment. It also became clear that the responsibility of ensuring sustainable development cannot only be on any specific governmental body but also on all public–private organizations, including those of higher education. Every entity should actively participate in the task to achieve this final goal for everyone [27].

Table 2. Agreements/treaties regarding climate action specifically based on higher education and urban climate.

Obligations	Declarations/Agreements/Treaty
The lack of acknowledgment of HEIs’ operational and functional activities that could impact or accelerate sustainable environment.	UN conference, 1972; The Tbilisi Deceleration, 1977; The Halifax Declaration, 1991; The Rio Agenda, 1992; The Paris Agreement, 2015; The New Urban Agenda, 2016.
The acknowledgment of “Environmental education” only as a measure of fighting climate change globally.	The World Declaration on Higher Education, 1997; The Declaration on the Responsibility of Higher Education, 2005; Charter of the Netherlands Universities, 1998; Charter for an Alliance of French Universities, 2008; AAU Resolution on Green Energy Research and Training, 2009.
The acknowledgment of CO2 emissions generated from activities of HEIs’ research, education, and campus operations.	The Talloires Declaration, 1990; The World Declaration on Higher Education, 1997; The American College & University Presidents’ Climate Commitment (ACUPCC), 2007; AAU Resolution on Green Energy, 2009; The International Sustainable Campus Network (ISCN)/Global University Leaders Forum (GULF) Charter, 2010; Peoples’ Sustainability Treaty on Higher Education, 2012; The United Nations Decade of Education for Sustainable Development, 2014.
Acknowledgment of the need for special assessment and monitoring tools for ensuring campus sustainability.	The American College & University Presidents’ Climate Commitment (ACUPCC), 2007; The International Sustainable Campus Network (ISCN)/Global University Leaders Forum (GULF) Charter, 2010; The United Nations Decade of Education for Sustainable Development, 2014.
An emphasis on “Sustainable campus operation”, a combined effort to achieve campus sustainability.	The Talloires Declaration, 1990; IAU Kyoto, 1993; The World Declaration on Higher Education, 1997; ACUPCC, 2007; Charter for an Alliance of French Universities, 2008; The United Nations Decade of Education for Sustainable Development, 2014.

Source: modified from [28].

Table 2. Agreements/treaties regarding climate action specifically based on higher education and urban climate.

Obligations	Declarations/Agreements/Treaty
The lack of acknowledgment of HEIs’ operational and functional activities that could impact or accelerate sustainable environment.	UN conference, 1972; The Tbilisi Deceleration, 1977; The Halifax Declaration, 1991; The Rio Agenda, 1992; The Paris Agreement, 2015; The New Urban Agenda, 2016.
The acknowledgment of “Environmental education” only as a measure of fighting climate change globally.	The World Declaration on Higher Education, 1997; The Declaration on the Responsibility of Higher Education, 2005; Charter of the Netherlands Universities, 1998; Charter for an Alliance of French Universities, 2008; AAU Resolution on Green Energy Research and Training, 2009.
The acknowledgment of CO2 emissions generated from activities of HEIs’ research, education, and campus operations.	The Talloires Declaration, 1990; The World Declaration on Higher Education, 1997; The American College & University Presidents’ Climate Commitment (ACUPCC), 2007; AAU Resolution on Green Energy, 2009; The International Sustainable Campus Network (ISCN)/Global University Leaders Forum (GULF) Charter, 2010; Peoples’ Sustainability Treaty on Higher Education, 2012; The United Nations Decade of Education for Sustainable Development, 2014.
Acknowledgment of the need for special assessment and monitoring tools for ensuring campus sustainability.	The American College & University Presidents’ Climate Commitment (ACUPCC), 2007; The International Sustainable Campus Network (ISCN)/Global University Leaders Forum (GULF) Charter, 2010; The United Nations Decade of Education for Sustainable Development, 2014.
An emphasis on “Sustainable campus operation”, a combined effort to achieve campus sustainability.	The Talloires Declaration, 1990; IAU Kyoto, 1993; The World Declaration on Higher Education, 1997; ACUPCC, 2007; Charter for an Alliance of French Universities, 2008; The United Nations Decade of Education for Sustainable Development, 2014.

Source: modified from [28].

In the UK, the building sector is marked as the main energy consumer, with 40% of the total country’s share [29]. In Canada, local HEIs generally consume around 60% of the electricity allocated for the combined educational institutes of different levels [30]. In the USA, the water consumption of educational buildings accounts for around 6% of total public water [31]. In China, the water and energy usage of HEI campuses is around four times higher than residential or other usages [32]. Globally, HEIs have been identified as one of the biggest shareholders and carbon emitters through consumed electricity and natural gas usage [29]. An HEI campus can be categorized based on several factors. Based on the university’s resources, infrastructure, geographic location, and operation, these tangible typologies can be justified. Along with other authors, Tan et al. [32] categorized campus assessment activity into three levels. For sustainability assessment and monitoring, the three levels of buildings, community or campuses, and city are crucial to identify the best practices. Their research conclusion was that “green buildings” could be the potential drivers among the three levels as they can influence the whole process from the micro-level. In addition to that, campuses consisting of several green buildings can be more energy-efficient, and having more energy-efficient campuses in a city can play a vital role in promoting zero-carbon practices on a city scale [33]. Beyond regional, contextual, and climatic differences, all university campuses around the world can be illustrated through these lenses of typologies. Additionally, it can be said that the physical type and size of university campuses have a great influence on users’ behavior.

According to UNEP, only a synchronized approach to combining global, regional, national, and local levels of action plans can mitigate environmental exploitation and ensure a sustainable future [5]. Among all the other public and private subsystems, HEIs resemble the multidimensional activity of a city interacting with different subsystems: education, administration, transport, housing, health, and food [34]. They have often been marked as a “small-scale city model” by numerous researchers [35]. Taking all that into account, HEI campuses have become a beacon of hope for change. Along with its scalable infrastructure, a zero-carbon campus can take the lead and pave the way for practicing, promoting, and demonstrating the transition to a zero-carbon city.

3. The Ways of Calculating the Carbon Emissions of University Campuses

The initial idea of calculating carbon emissions came from simply the willingness to take account of the activities of an organization that emits GHGs. Previous studies and research have highlighted taking the initiative of critically analyzing the potential emission factors of an entity, which means participating in the benchmarking and assessment of the emission activities and evaluating the strengths and weaknesses of the organization to discover the most efficient practices and policies to adopt in the future to strengthen its sustainability. In Kulkarni’s research [36], he explained that several countries have predicted that rapid globalization and urbanization will bring an energy crisis and will require a massive low-carbon transition. Following that, as carbon emissions have become a defined threat to climate change, he further explained the importance of evaluating the carbon footprints ofpublic–private, non-state actors and services, which would be a step toward reducing carbon emissions. In March 2004, the World Resources Institute (WRI) and World Business Council for Sustainable Development (WBCSD) first came up with “The Greenhouse Gas Protocol (GHGP): A Corporate Accounting and Reporting Standard” [37]. They categorized GHGs into Scope 1, 2, and 3 based on the source. It is now the most widely used accounting tool to track the GHG emissions of organizations, industries, and cities. Scope 1 GHG emissions are also called “direct emissions through the combustion of fuel or electricity” (a company owning a fuel- or electricity-consumption-based vehicle). Scope 2 GHG emissions are emissions generated from the purchase of electricity consumed by the organization. These emissions are also considered “indirect emissions” (purchased electricity and steam heating–cooling). Scope 3 refers to indirect GHG emissions that are a consequence of the organization’s activities but which the organization does not have direct control over (employee commuting, waste generated in operation, and purchased goods or services) [38]. Wright et al. [39] defined “Carbon foot printing” as the “determining factor of GHG emission in terms of carbon dioxide equivalents (CO₂e)”. He added that the summation of total GHG emissions includes direct and indirect causes by an individual, an organization, an event, or a product. He further added that this term is also used interchangeably with other terms, such as “carbon accounting” or “carbon inventory”.

The previous studies and research were analyzed based on several factors like the type of study, specific targets, scopes, campus-scale factors, study region, climatic conditions, assessment methods, types of data, implementation, and the feasibility of the studies. The analyzed studies were categorized into four types: demonstrations, literature reviews, case studies, and pilot projects (see Table 3). Dawodu et al. [40] reviewed over 1000 articles dating from 2013 to 2019 and came up with 12 dimensions that can be the parameters to assess the sustainability of a campus. The result of the systematic literature review concluded that environmental awareness and environmental education hold great value and potential in the previous research. The authors divided all the analyzed methods into three groups – (a) account assessment, (b) narrative assessment, and (c) indicator-based assessment – and evaluated their feasibility. According to Jain et al. [41], some universities joined national international group agreements to work closely towards achieving target-based carbon neutrality, and some evaluated their carbon footprint and restructured their activities to reduce emissions. They developed a framework, “Carbon Neutrality and Sustainability in educational campuses (CaNSEC),” where 24 indicators were identified based on four major components: environment, society, economics, and academics. The framework was successfully tested at TERI University in New Delhi, investigating all three scopes of emissions. In their article, Amaral et al. [42] illustrated a unique perspective on campus sustainability assessment study and research. Through a systematic review of the empirical-based scientific literature, the authors tried to analyze the triggers of “unsuccessful” and “failed” projects. The study categorized all the triggers into four groups: technical, economic, climatic, and behavioral. The result shows that inadequate planning design and a lack of proper monitoring were the prime reasons for unsuccessful projects. The identification of potential emission indicators and project monitoring is certainly essential for a successful sustainability assessment of a university campus. The noticeable factors of past research can be viewed through the lens of campus type, the objectives of the studies, and similarities in addressing issues like user behavior, energy use patterns, waste generation, etc. Prime factors could be the variations in incorporating scope indicators (1, 2, and 3) partially or completely in different contexts. Charles et al. [43] developed the “Designing Climate Action and Regulations for Sustainability (DCARB)” framework to explore multiple tracks to achieve carbon neutrality based on user input and parameter variability. Ohio State University was selected as the case study following a limited-scope carbon neutrality target. The study was primarily focused on power generation (purchased electricity and stationary fuel combustion) and GHG emissions. Following that, the carbon sequestration potentials of natural resources and other carbon offset schemes were analyzed. The analysis produced the following findings: (1) immediate investments in technological advancement can reduce overall energy costs and emissions; (2) ecological resources should be prioritized to achieve the benefits; and (3) a single action alone is not enough to achieve carbon neutrality on campus. Larsen et al. [44] adopted a hybridized Environmental Extended Input–Output (EEIO) model for investigating the carbon footprint of the Norwegian University of Technology and Science (NTNU). For incorporating all three (1, 2, and 3) scopes of GHG emissions, they emphasized the initial steps of identifying target areas in the carbon footprint calculation process across different schools and departments of the NUTS campus. Meida et al. [45] evaluated the carbon footprint of De Montfort University using the “Consumption-based” method and discovered that Scope 3 emissions accounted for almost 79% of the total university GHG emissions table. Despite different system boundaries, a dominance of Scope 3 factors was also noticed in the case of York and Lancaster University in the UK. The Scope 3 emissions mostly included upstream energy supply, student and staff commuting, and procurements. Li et al. [46] adopted the “water–energy–carbon nexus” at the North China University of Water Resources and Electric to estimate the power usage patterns of carbon emission sources and natural carbon sinks. The different characteristics of the water–energy–carbon nexus of different functional areas of the campus were also examined. The results showed that the total campus carbon emissions of the campus were 32,120 t of CO₂, and carbon absorption was 557 t of CO₂. Heat generation and purchased electricity consumption were the prime sources of carbon emissions, and the potential carbon sinks were grassland, woodland, and waterbodies on the campus. Gu et al. [34] also explored the “nexus analysis perspective” in their study entitled “Quantification of interlinked environmental footprints on a sustainable university campus” to examine five key indicators: water, energy, waste, food procurement, and carbon emissions. The overall energy footprint, carbon footprint, and water footprint for Keele University in the United Kingdom for the 2015–2016 academic year were 42,202 MWh, 14,393 tons of CO₂e, and 532,415 m3, respectively. The Scope 3 emissions mostly consisted of wastewater treatment, waste disposal, and food procurement [36]. Using a unique program they created, called CO₂UNV, Valls-Val and Bovea [47] were able to calculate the CO₂ equivalent (CO₂e) emissions for Scopes 1, 2, and 3 for a whole university consisting of various buildings and units. Evaluating the CF and CO₂e offsets of the Universitat Jaume I (Spain) over time for Scopes 1, 2, and 3 over three years (2017–2019), the results were 0.492 t of CO₂e per student and 0.030 t of CO₂e per m², which are lower than the previous three years (2016–2018), i.e., 0.578 t of CO₂e per student and 0.036 t of CO₂e per m². Aroonsrimorakot et al. [48] calculated the GHG emissions at the Faculty of Environment and Resource Studies, Mahidol University, Salaya Campus, Thailand by implementing the guidelines of the Intergovernmental Panel on Climate Change (IPCC), and found that purchased electricity was the greatest contributor to the overall GHG emissions. Sreng and Yiğit [49] also used the IPCC method to evaluate the carbon emissions of the Sakarya University Campus. The overall GHG emissions of 2015 were 12,331 t of CO₂e, where purchased electricity consumption was the leading source of emissions (65.4%). The usage of natural gas was responsible for 16.3% of the total emissions. The research suggested that Scope 2 emissions contributed more than 50% of the total amount. To evaluate the total emissions from purchased electricity and the potential of photovoltaic (PV) panels as an alternative energy, Yazdani et al. [50] adopted the IPCC method to analyze the University Technology Malaysia (UTM) campus. It was discovered that UTM’s entire carbon footprint in 2011 was 57,576 Mt of CO₂. The dominant source was Scope 2 (purchased electricity), which accounted for 84% of the total carbon footprint. Also, 4.21 kWh/m² to 5.56 kWh/m² was the annual average daily solar irradiation for Malaysia, which had great potential to be used as an alternative to electricity and reduce costs and CO₂ emissions.

Table 3. Comparison of the previously used evaluation methods of HEI campus GHG status and carbon accounting.

University	Country/ Region	Type of Study	Scale	Target/Goal	Research Content		Sources
					Emission Sources	Accounting Method
NTNU	Norway	Demonstration	Campus scale	Calculate the carbon footprint of students.	Scope 1, 2, and 3	Environmental Extended Input–Output (EEIO)	[44]
NCUWREP	China	Case study	Campus scale	Investigate water, energy, and carbon interaction.	Scope 1, 2, and 3; carbon offset	Nexus model	[46]
De Montfort University	UK	Case study	Campus scale	Calculate campus carbon footprint.	Scope 1, 2, and 3	IPCC method	[45]
Carleton University	Canada	Demonstration	Building scale	Identify the upstream environmental and economic impacts of buildings and campus performance.	Scope 1 and 2	The proposed method used Sankey layout code to generate Scalable Vector Graphics (SVG)	[51]
South Bank University	UK	Pilot project	Building scale	Develop a forecasting model for higher educational buildings.	Scope 2	The multiple regression (MR) technique was used for one dependent variable and six explanatory variables	[29]
Global study	Global	Systematic literature review (SLR)	Campus scale	Develop a universal framework to link HEIs’ education to the SDGs.	The identification of scopes for facilitating the inclusion of the SDGs into higher education		[27]
TERI University	India	Demonstration	Campus scale	Assess carbon neutrality and sustainability in higher education campuses.	Scope 1, 2, and 3	CaNSEC	[41]
University of Jaime I	Spain	Demonstration	Campus scale	Develop a carbon assessment tool to quantify the CO2 equivalent (CO2e).	Scope 2 and 3	CO2UNV	[47]
University of Pertamina	Indonesia	Demonstration	Campus scale	Carbon emission assessment toward a green campus and the promotion of environmental sustainability.	Scope 2 and 3	IPCC, WARM model	[52]
Ohio State University	USA	Demonstration	Campus scale	Explore different pathways towards achieving carbon neutrality on university campuses, based on user input and parameter variability.	Scope 1 and 2	Development of Designing Climate Action and Regulations for Sustainability framework (DCARB) based on user input and mixed-integer linear program (MILP)	[43]
Universal study	Global	Literature Review	Building scale	Analyze the energy consumption patterns and energy-saving strategies of educational buildings.	Systematic literature review using descriptive statistical analysis		[53]
Technical University of Madrid	Spain	Demonstration	Building scale	Calculate the carbon footprint; Evaluate the status of implementing a carbon management plan.	Scope 1, 2, and 3	A compound method based on financial accounts	[54]
Regional Study	USA	Case study	Campus scale	Estimating greenhouse gas emissions from HEIs; Evaluating the carbon emissions from bachelor’s, master’s, and doctorial activities.	Scope 2 and 3	IPCC	[55]
Universal study	Global	Literature review	Campus scale	A literature review of unsuccessful studies focused on energy and buildings.	Systematic literature review based on four factors: technological, behavioral, economic, and climatic		[42]
Universal study	Global	Literature review	Campus scale	Investigating context indicators and parameters for the design and assessment of a sustainable campus.	Campus Sustainability Assessment Tools (CSAT) development		[40]
Regional Study	China	Case study Demonstration	Campus scale	Develop an incomparable sustainability evaluation framework for Chinese universities.	Framework development based on operation and management indicators		[56]

Table 3. Comparison of the previously used evaluation methods of HEI campus GHG status and carbon accounting.

University	Country/ Region	Type of Study	Scale	Target/Goal	Research Content		Sources
					Emission Sources	Accounting Method
NTNU	Norway	Demonstration	Campus scale	Calculate the carbon footprint of students.	Scope 1, 2, and 3	Environmental Extended Input–Output (EEIO)	[44]
NCUWREP	China	Case study	Campus scale	Investigate water, energy, and carbon interaction.	Scope 1, 2, and 3; carbon offset	Nexus model	[46]
De Montfort University	UK	Case study	Campus scale	Calculate campus carbon footprint.	Scope 1, 2, and 3	IPCC method	[45]
Carleton University	Canada	Demonstration	Building scale	Identify the upstream environmental and economic impacts of buildings and campus performance.	Scope 1 and 2	The proposed method used Sankey layout code to generate Scalable Vector Graphics (SVG)	[51]
South Bank University	UK	Pilot project	Building scale	Develop a forecasting model for higher educational buildings.	Scope 2	The multiple regression (MR) technique was used for one dependent variable and six explanatory variables	[29]
Global study	Global	Systematic literature review (SLR)	Campus scale	Develop a universal framework to link HEIs’ education to the SDGs.	The identification of scopes for facilitating the inclusion of the SDGs into higher education		[27]
TERI University	India	Demonstration	Campus scale	Assess carbon neutrality and sustainability in higher education campuses.	Scope 1, 2, and 3	CaNSEC	[41]
University of Jaime I	Spain	Demonstration	Campus scale	Develop a carbon assessment tool to quantify the CO2 equivalent (CO2e).	Scope 2 and 3	CO2UNV	[47]
University of Pertamina	Indonesia	Demonstration	Campus scale	Carbon emission assessment toward a green campus and the promotion of environmental sustainability.	Scope 2 and 3	IPCC, WARM model	[52]
Ohio State University	USA	Demonstration	Campus scale	Explore different pathways towards achieving carbon neutrality on university campuses, based on user input and parameter variability.	Scope 1 and 2	Development of Designing Climate Action and Regulations for Sustainability framework (DCARB) based on user input and mixed-integer linear program (MILP)	[43]
Universal study	Global	Literature Review	Building scale	Analyze the energy consumption patterns and energy-saving strategies of educational buildings.	Systematic literature review using descriptive statistical analysis		[53]
Technical University of Madrid	Spain	Demonstration	Building scale	Calculate the carbon footprint; Evaluate the status of implementing a carbon management plan.	Scope 1, 2, and 3	A compound method based on financial accounts	[54]
Regional Study	USA	Case study	Campus scale	Estimating greenhouse gas emissions from HEIs; Evaluating the carbon emissions from bachelor’s, master’s, and doctorial activities.	Scope 2 and 3	IPCC	[55]
Universal study	Global	Literature review	Campus scale	A literature review of unsuccessful studies focused on energy and buildings.	Systematic literature review based on four factors: technological, behavioral, economic, and climatic		[42]
Universal study	Global	Literature review	Campus scale	Investigating context indicators and parameters for the design and assessment of a sustainable campus.	Campus Sustainability Assessment Tools (CSAT) development		[40]
Regional Study	China	Case study Demonstration	Campus scale	Develop an incomparable sustainability evaluation framework for Chinese universities.	Framework development based on operation and management indicators		[56]

Among the above-mentioned methods, the Scope 3 indicators were merely included for analysis in several cases. Scope 3 emissions mainly consist of indirect GHG emissions that are a consequence of an organization’s activities outside its boundary which the organization does not have direct control over (employee commuting, waste generated in operation, purchased goods or services, etc.). Due to a lack of reliable data and a lack of accountability, Scope 3 indicators were often left out of the equation. However, the researchers who included Scope 3 emission factors in case studies of different organizations saw that they contributed significantly to the overall carbon footprint. Similarly, in the case of HEIs, Scope 3 has also proven to be a potential factor. Among all Scope 3 indicators, employee and student commuting, waste treatment, and food procurement are prominent. The large contribution of indirect Scope 3 emissions indicates the need to incorporate this scope into the study to create a complete CF inventory [44]. Some researchers included partial Scope 3 indicators in their research using different methods. Ridhosari and Rahman [52] also calculated 3 scopes indicators using the Intergovernmental Panel on Climate Change (IPCC) methods. They included Scope 3 factors of faculty, staff, and students commuting using driving distance method and fuel emission coefficient method for calculation. According to their findings, power usage accounts for 92.3% of the university’s total carbon emissions, followed by transportation (6.7%) and waste (1.0%). Along with consumption-based carbon accounting, several researchers tried to evaluate the carbon sequestration potential of natural carbon sinks within the campus boundary.

According to the studies of the American College and University Presidents’ Climate Commitment (ACUPCC), a very important notion has been identified in terms of campus sustainability; that is, the “achieved” tag was more celebrated than a sense of responsibility. The mandate of the committee suggested that campus carbon neutrality should be the first step towards starting a futuristic broader-scale decarbonization system. Considering factors like campus size, campus setting, location, natural resources, technological equipment, functionality, and management practices, the process of achieving neutrality can be difficult and heterogeneous, yet not impossible. Vahid created a system dynamics model of energy-based sustainability development initiatives that take advantage of both efficiency and conservation. The model formalizes the paid-from-savings program through a sustainability program at Texas A&M University, USA [25]. In the study, they generated five hypothesis scenarios, and the result showed that energy and money are saved significantly by both efficiency and conservation, but maintenance is necessary for conservation to continue. Villiers et al. [57] discovered that only 253 tons of CO₂ were anticipated to be sequestered annually over the following ten years from 2011 while assessing the potential of carbon sinks at Kiwi University, New Zealand. It was calculated that 4137 trees were storing 5809.4 t of CO₂ in 2011 and will store 8334 t of CO₂ by 2022 based on height, trunk diameter, and age.

The most crucial finding of the analysis was that the majority of the studies lacked the acknowledgment of the “scale factor”. Another important finding was that studies were mostly based on developed countries (USA, UK, EU, and China). The evaluation methods of energy consumption and carbon accounting were developed and used in the same regions. The climatic conditions, contextual scenario, energy consumption, and demand are different from developing countries. Despite being more vulnerable climatically, very few studies have been carried out on developing countries. A lack of scaling up and collaborative measures was found as well. On the other hand, it was noticed that sufficient knowledge of “system inventory” and campus-based “carbon inventory” development was provided in these studies. Several recommendations based on different scenarios have been drawn. According to the study by Dawodu et al. [40], only a small number of studies on “Campus Sustainability Assessment” have been found outside of North America, Europe, East Asia, and China. However, sustainability should be given high priority in other developing and underdeveloped nations. At this point, a comprehensive and adaptable framework for evaluating the energy consumption of HEIs and strengthening sustainability is absolutely necessary.

4. The Methods of Interchangeable Scaling of Zero-Carbon Practices

Windem [58] explained that “scaling up” is a subtle mechanism by which such niche developments impact the “regime,” and a gradual process made possible by local–global learning mechanisms that take place in communities but are frequently hindered by overly protective legal or financial policies. He also added that to avoid this crisis, scaling up should be completely based on performance feedback. Firstly, the idea of “scale” evolves from the theories of natural and social sciences focused on complex conditions in different times and spaces [59]. Among other professionals, planners rely on the assumption that an existing hierarchy of spatial scale is something natural, given, and fixed in context [60]. Secondly, “scaling” refers to the process of transferring information from one dimension to another, with a specific direction categorized as scaling up or scaling down [59]. In the book Scaling Up: A Vision to a Large-scale Change, Cooley and Kohl [61] illustrated a scaling-up management (SUM) framework that consists of three steps, the first of which includes developing a vision, determining the feasibility of the scaling-up process, preparing the scale-up plan, and adapting strategies to achieve stability in progression (Figure 1). According to Dixon and Eames [62], the idea of “scale” holds great value in terms of achieving sustainability because, even after the fixed span of activity and result, directly or indirectly, the results and benefits tend to be sustained more in the future. To some extent, the “scaling-up” term of this study can resemble the theories of geographical dimensions and spatial hierarchies of landscape ecology. Before the application of any policy, defining a scale is essential to ensure a proper alignment with the point of intervention [62]. Scaling-up the management framework decomposes the “Expansion” method into three categories: expansion, replication, and collaboration [61]. Based on this mode of study, the term expansion suggests increasing the scope of operations of an entity or organization that essentially developed as a small-scale initiative or idea. As an example, a “shop” of a certain brand can be mentioned. To increase its market demand or sales, it requires growth. To increase growth, it has to “expand” its territory by setting up new shops in other locations.

Replication essentially refers to a service, a process, or a specific technology that one entity or institution can adopt from another. Replication can occur within similar entities or organizations or dissimilar entities as well. Policy adoption is a great example of a replication scaling-up method. A policy related to a specific activity or method is originated by one organization and later adopted by others to accelerate the process of reaching the united target. The third method of scaling up, “Collaboration”, stands in the common area between the expansion and replication methods. Collaboration generally refers to developing partnerships between two or more entities and operating under single governance. The joint venture and partnership of different companies is a great example of “collaboration” methods of scaling up.

With the help of these methods, a vision can be developed to scale up an idea, practice, or project. The basic idea of “scaling” refers to the process of transferring information from one dimension to another, with a specific direction categorized as scaling up or scaling down [59]. Scaling requires when the vision of an idea or practice includes a greater impact on the population, regions, and beyond. Similarly, in terms of achieving sustainability, the idea of “scale” holds great value because, even after the fixed span of activity and result, directly or indirectly, the results and benefits tend to be sustained more in the future [62]. With the help of advanced knowledge and modern technology, both state and non-state actors have been able to provide innovative solutions to numerous economic, social, cultural, and environmental problems to their citizens. These solutions usually come in the form of service, technology, or a combination of both. Many of these solutions hold great potential for entrepreneurial, intellectual, and social value. Specifically, in terms of urban sustainability, any small-scale solution that has the potential to solve a small-scale problem should be scaled up for greater impact [63]. However, several small-scale solutions fail to influence mass audiences to adapt to the greater change. Some environmental initiatives at a small scale also might not work properly. In their study, Yan et al. [64] emphasized the shift of environmental control and resource management studies from the city to the country level. They explained how metabolic studies at the city scale face problems due to the lack of support from their surroundings. At the country level, studies of self-sufficiency and organization are more relatable. Finally, they concluded their study with the remark that, for successful analysis, the methods should be adopted based on the goals. In a study based on vegetable farming in South Uruguay, it was found that crop-related research faces obstacles in reaching farm-level practice due to the mismatched objectives of the research and the economic factors of the farm [65]. A “pilot project” refers to the smallest-scale implementation of an idea into reality to evaluate the feasibility and potential of the solution [66]. For scaling up any idea or practice, it is essential to have a clear vision and strategies for gradual expansion through collaboration [67]. Bundgaard and Borrás [65] analyzed 17 “smart city” pilot projects across the USA, Europe, and Asia, intersecting the idea of innovation, governance, and knowledge management. The authors concluded that the “replication” method is the most complicated form of scaling up. By studying the “Canadian international food security research project,” it was found that implementing “innovation” at the starting point of scale-up and systematic change in the project operation can accelerate the scale-up process [68]. For scaling up a project or an idea, the involvement of two entities is required—the originating entity that develops the idea or the pilot project and the target user or adopting entity [61].

In terms of transitioning to new city-scale practices, not only does adopting technology play a vital role, but so do non-technological initiatives [69]. The active participation and collaboration of multiple actors in the city are essential for adopting a city-scale zero-carbon transition.

5. New Framework Development for Campus Sustainability Analysis by Identifying the Campus Typology, Estimating Natural Resources and the Built Environment, Analyzing Behavior Patterns, and Carbon Accounting

This paper intends to develop an extensible framework to analyze the current operational and functional practices of energy consumption and CO₂ emission. Furthermore, it also creates the opportunity to evaluate the scalability factors of these practices on a city scale. The proposed framework consists of four major steps that include specific measures, methods, and outcomes that individually address multiple parameters to assess the status of an HEI campus (Figure 2).

5.1. The Identification of Campus Typology

The first step of evaluation is to categorize the campus based on its physical area, visible boundary, and infrastructure. Through a physical site survey, observation, and digital mapping, the desired result can be revealed in the form of three categories: (1) single buildings with no defined boundary; (2) multiple buildings with defined boundaries; and (3) multiple buildings with no defined boundary (Figure 3). The basic facilities and functions of an HEI can also be identified through this evaluation process.

5.2. The Estimation of Natural Resources and the Built Environment

The second step of evaluation is a detailed evaluation of campus resources and the infrastructure of the campus using physical site surveys, a secondary literature review, interviews, digital mapping using Google Maps^®, and AutoCAD^® 2020 drawing to identify the ratio of land and built structures. Following that, the approximate natural resources of the campus (forest, water, and grassland) are calculated along with the functional built area. The functional areas can also be categorized as academic, administrative, recreational, and residential zones.

5.3. Population and Behavior Pattern Analysis

The third evaluation step consists of the population and the identification of emission indicators through user behavior patterns. The first phase deals with the estimation of population and ratios based on teacher–student–staff roles and their activities on campus. The second phase intends to identify the user behavior pattern in terms of energy usage, water consumption, and activity preference, which leads to the identification of emission indicators.

5.4. Carbon Accounting and Sequestration

The fourth and final phase of the framework is completely based on carbon accounting. Following the WRI-WBCSD GHG Protocol Corporate standard methods (WRI, 2015), the emission sources are categorized into Scopes 1, 2, and 3. The activity data and local/national emission factors of specific emission sources are needed for the calculation. The activity data are collected from the regulatory body in the form of electricity consumption bills, fuel consumption bills, and water consumption bills. In the illustrated diagram (Figure 4) the GHGs which were considered for calculation are marked in red circle.

The proposed framework is capable of giving instant results to analyze the CO₂ emission status and energy consumption of an HEI campus, regardless of geographical limitations, climatic variations, and campus types. This framework can be used for both campus-scale and building-scale educational facilities. To some extent, it can be implemented on nonacademic campuses as well. Based on the specific requirements of the assessment, this framework can also be used partially. These scalable features of this framework have the potential to explore the future of city-scale zero-carbon practices (Figure 5).

6. Discussion on Exploring the Scalability Factors

Scale is a measuring determinant. Similarly, “scaling” refers to the process of transferring information from one dimension to another, with a specific direction categorized as scaling up or scaling down [70]. In terms of achieving sustainability, the idea of “scale” holds great value because, even after the fixed span of activity and result, directly or indirectly, the results and benefits tend to be sustained more in the future [62]. Through the lens of zero-carbon transition, both scaling-up and scaling-down processes are essential. Based on specific climate actions and goals, certain climatic measures can be scaled up from an institutional level to a city level and vice versa.

With HEIs being one of the key actors of a city system, a radical change in the functionality of one or more HEIs can influence the system or the operation process. Zero-carbon practices at the institutional level are found to be solely dependent on the behavior and practices of their users. An HEI campus was addressed as the subject of this study. To explore the modes of the zero-carbon city transition, three core parameters of scaling-up methods (expansion, repetition, and collaboration) are discussed.

6.1. “Expansion” through Educating the Future Generation

A higher education institute is a link between academia, industry, and government. HEIs can influence and collaborate with the government and industry to shape the socioeconomic structure of the country through education, research, and innovation [34]. It is expected that along with educating generations, an HEI should promote sustainability and unleash its beneficial impacts on the community level and beyond [71] (Figure 6).

As humans, fundamentally, we seek help from knowledge and education when facing any crisis. Similarly, it is an educational institute’s principal responsibility to enlighten the people to address the environmental crisis and seek its solution [72]. It is of utmost importance to rethink the medium of environmental education to accelerate the change. The end goal or target might differ from campus to campus, university to university, and country to country, but the core idea should be expressed through “Inclusive Environmental Education.” Inclusive environmental education can initiate and accelerate sustainability research, public outreach, partnerships with private–public organizations, and collaboration with national and international organizations [73]. Mandatory environmental education refers to a unified curriculum regardless of the different units, roles, and disciplines of the users. It is primarily focused on giving the campus user better exposure to the extent of the environmental crisis. A proper understanding of the current environmental crisis and on-campus practices can help them build a more climatically resilient campus culture. Incorporating real-life tasks to understand the current environmental problems of their campus and find the solutions should make this learning a part of their campus lifestyle. Similar practices involving teachers and staff will accelerate the overall operation and practices of the HEI towards a more sustainable path. This education will have a long-term impact on the users, especially the students who will soon be leading the generation. Education will make them resilient and adaptive for the future. Considering the number of total tertiary education institutes in Rajshahi City, a larger impact can be created by adopting “inclusive environmental education” in other HEIs as well. Encouraging similar behavior on campus regarding energy usage, transportation, and waste generation can bring significant change in city-scale natural resource consumption and waste generation. Educating the future generation following the theory of “expansion” has the potential to influence the current youth to have lifelong and more impactful learning about the environment. Based on the assumption that 1% of the carbon emissions of a city can be reduced through education, combining nine HEIs of Rajshahi City can reduce up to 9% of the total emissions. For such results, local and context-based environmental education curricula should be adopted. Authentic data regarding potential threats, harmful activities, and ways of mitigation are essential.

Youth around the world are less engaged in and expressive in pro-climate behaviors than other age groups [74,75,76]. The irrelevant and incompetent expression of the environmental crisis has failed to attract them. However, it has also been identified that they hold the potential to amplify societal change with their social and technological skills [76]. The proposed framework can be utilized to critically identify the behavior and preferences of the users, mostly youths, and can also be used to draft policies that are relevant to and graspable by individual age groups.

6.2. “Demonstration” to Encourage Replication of the Sustainable Campus Practices

The idea of “preserving biodiversity” explains how protecting natural resources is an effective method to bring ecological balance into the campus boundary, and exhibits the advantages of a sustainable campus [77]. Not only a university campus, but also any other academic or nonacademic campus filled with natural resources like grasslands, water bodies, and forests, can promote the advantages of its enriched microclimate. The term “living laboratory” was first used in the guidelines for “promoting sustainable campus landscapes” initiated by the Association for the Advancement of Sustainability in Higher Education (AASHE) together with the Arbor Day Foundation in 2013 [77]. A resourceful campus can be a testbed for all the theoretical and technological experimental methods of enhancing sustainability. The implementation of action-based environmental education, community-based social innovation, assignments, and projects can help utilize the true value of a sustainable campus. Spreading the benefits of a zero-carbon campus and its technological advancements to society will likely diminish the boundaries between the producer of knowledge and the end user or benefactors [78]. According to Hoyos et al. [79], climate action requires leadership that can bring change in production and consumption patterns. Leadership is expected from all the different organizations of society in this moment of climatic crisis. They also added that only when these organizations are aware of their activities and their impact can climate action plans be implemented (Figure 7).

A privately or public-owned campus that has rich biodiversity and natural resources can create benefits for not only the users but also the surroundings. These initiatives can serve as pioneers, demonstrators, and promoters of sustainable development targets of a city [59]. A zero-carbon campus can be the most impactful “promotor” of zero-carbon practice. Not only should a campus exhibited as a laboratory, running innovative research and adopting technologies demonstrating the benefits of sustainability, serve as an example for students or teachers, but it will also give great exposure to society to the potential of this practice [80]. This demonstration will certainly make HEIs a leader in this transitional path. A low-carbon sustainable campus can be a pioneer, promoter, and demonstrator of sustainable development. A total of 42% carbon sequestration was estimated from the total emitted carbon dioxide of the Rajshahi University campus. Rajshahi City has 9 HEIs, 3 higher secondary degree colleges, and 10 high schools with significantly resourceful campuses. Based on our assumption, the proper utilization of these institutional campuses and implementing policies can ensure significant carbon sequestration from the total carbon emissions of the city.

Most of the studies regarding campus sustainability and sustainability transition lacked scale factor assessments of the university campuses. The proposed framework not only addresses the scale factor but also analyzes the potential of a campus to be an example for society. Besides the natural resources, the framework also investigates the ratio of the built environment and the scope of adopting technological advancement.

6.3. “Collaboration” through Developing a Strategic Alliance for Collective Benefit

One actor or sub-actor of a system cannot contribute greatly to a radical transitional process. According to Maida and Beck [45], “sustainable practices” foster ecological, human, and socioeconomic health, with the presumption that all resources are finite and consequences are certain if not handled with precaution. Different government and nongovernment entities besides HEIs also accommodate multidimensional activities on their campus or premises (Figure 8).

Educating the users of the respective campuses and equipping them with the same innovation and technologies to preserve biodiversity will accelerate the action plan of enhancing city-scale sustainability. The city of Rajshahi accommodates several nonacademic campuses/complexes filled with natural resources. With the increasing population and demand for service, these campuses are also facing ecological imbalance and a loss of biodiversity and wildlife. For any act of re-engineering the city system, a planned, strategic, and coordinated approach is needed involving all the actors of the city. Urban-scale development projects related to city sustainability can also motivate the major stakeholders of the city to actively participate for their benefit [62]. To achieve zero-carbon status on a city scale, other public–private actors of the city, like governmental institutions and health care, industrial, and commercial entities, can replicate the practices of zero-carbon HEI campuses on their campuses/premises. The deep decarbonizing of different actors of society through adopting greater systematic changes should be the end goal of this scaling-up scheme. Nonacademic entities can also share the knowledge and research to advance their zero-carbon transition. The positive impact of adopting zero-carbon practices can unleash its benefits to the surrounding nonacademic campuses. Sharing the same ambition and aligning the goal with a zero-carbon HEI campus will only benefit its users and accelerate the transition process of a zero-carbon city. Incorporating different actors in the city, achieving targets, and fulfilling commitments will become a widespread reality.

The proposed framework tends to utilize nonacademic campuses as well to boost the zero-carbon city-scale transition. The framework has the flexibility of evaluating any campus regardless of its functionality. Following the steps gradually, a nonacademic campus can also be categorized, the natural resources and built-environment ratio can be estimated, and carbon accounting can be carried out. Sharing the same method and policies will bring collaboration between academic, nonacademic, public, and private organizations. Aligning the target and activities will bring change eventually.

7. Limitations of the Study

In order to further confirm the robustness of this approach in real practice, more in-depth analysis and testing results will be required. This study was developed for research and educational purposes. Due to limited access to primary data, the sample size was insufficient for major statistical measurement. The calculation was also impacted due to a lack of data on local emission factors and other inventories. Values from global or other regional functions were used in this study, which eventually impacted the scope of analysis of the study. A more comprehensive and detailed inventory of selected cases might bring satisfactory results as well. An in-depth analysis of user behavior patterns in energy consumption and environmentally friendly behavior will also be assessed to define a narrative in the future.

However, the developed framework has the flexibility to be used in different contexts and carbon accounting can also be carried out regardless of the sample size. Using the framework, campuses from different contexts and regions can be assessed. In the future, an essential advancement of the study would be a comparison of different campuses in one specific region. This will help the researcher to evaluate the status of the campus, their practices, and their potential to accelerate the zero-carbon transition of the city.

8. Conclusions

This study intended to evaluate the potential of community-level (campus-scale) climatic action plans to accelerate the process of the zero-carbon city transition. As the previous studies were found to be concentrated on specific geographic contexts, climatic conditions, and activity, the objective of this research was to develop a versatile and flexible framework that can be used by any university campus, regardless of its geographical border, to assess its status through the lens of zero-carbon campus pathways. Based on thorough literature reviews and analysis, it was found that HEIs hold great potential to become a threat and a safeguard of urban sustainability simultaneously. Without proper planning and management, the multidimensional activities of a university campus can cause stress to the local environment and ecological balance. On the other hand, by utilizing the knowledge and resources of a university campus, the benefits of research and innovation can be spread beyond its boundaries. Several methods of carbon accounting were identified globally. However, no universal methods were proven to be efficient due to geographical and climatic variations. By utilizing this opportunity, a framework was developed in order to calculate carbon emissions and evaluate the zero-carbon transition pathways of university campuses regardless of their climatic and contextual differences. Rajshahi University campus, situated in the Rajshahi district of Bangladesh with a user population of around 45,801 and land of 753 acres, was selected as a case study. By implementing the proposed framework, several findings were highlighted. According to the given method, the campus was identified as a “multiple building with defined boundary” (Type 2) in the first phase of evaluation. Based on the second phase of the framework, the ratio of the built structure, natural resources, and other detailed land use mapping identified the features of the campus in specific numbers. Based on the third assessment phase of the framework, the behavior pattern of the users was identified. The ratio of student teachers living on campus, primary transport, the amount of water used daily, and the amount of consumed meals on campus were found. In the last part of the third phase of evaluation, it was found that the campus had no environmental protection for sustainability-related activities. The users of the campus were not aware of the facts of campus sustainability. No steps to reduce water, electricity, or fuel had been proposed by the university authority. Most of the students added that they did not have any mandatory environmental education included in their curriculum. The fourth phase of carbon accounting exposed the carbon emission amount of the campus through different scope indicators. It was found that Rajshahi University emitted 1900.71 t of CO₂ in the academic year 2022. Considering the total user population of 45,801, the per-capita emission of the users was found to be 0.041 t of CO₂. Among all the emission sources in Scope 2, indirect GHG emissions were the biggest contributor to GHGs in the year 2022. Scope 2 emissions were mainly generated from purchased electricity, with 69% of the total emissions. The second-highest-emitting source was Scope 3 waste dumping in landfills, with 19%. Fuel combustion for transport and crop cultivating was the lowest generator of GHGs, with 12%.

Finally, the potential of scaling up the zero-carbon practices from the campus to the city scale was examined in light of three upscaling methods: (1) expansion—through educating the future generation, (2) demonstration—preserving the biodiversity of institutional campuses, and (3) collaboration—strengthening sustainability alliance through sharing knowledge and innovation.

Policy Implications

• The assessment of campus activity status: The first step towards achieving sustainability at the campus level or broader aspects should be the evaluation of the current operation. An assessment of every activity of the campus and its users which has the potential to contribute to GHG emissions should be conducted. The university authorities must take this step first before expecting its users to participate in different ways.
• Mandatory education: After obtaining a clear picture of the contribution or the potential of the campus operations to generate GHG emissions, the data should be shared with all the users of the campus. Mandatory education about specific campus-based activities, their harmful effects on the environment, ways to reduce the impact, etc., should be provided, as well as specific context- and target-based education for all the users of the campus.
• The development of a data inventory: The development of a data inventory is a very important task for the campus authority to take account of accurate actions. This includes data regarding the population, energy consumption, the demand and supply of energy, the identification of insufficient practices, detailed transport travel and fuel consumption, etc.
• The installation of alternative energy sources: A campus like the one in this study, it should have some alternative energy sources like solar panels, biogas, etc. Even after generating a huge amount of solid waste and wastewater, this campus currently does not have any treatment plant for recycling or reusing practices. Biofuel and biogas can be generated from waste by using the appropriate technology on campus. The huge potential of installing solar panels was identified on campus. The roofs of buildings can be used for setting up solar panels which can contribute significantly to supporting the electricity demand of the campus users.
• Initiating new research: For technical advancement, knowledge sharing, or innovation, research is very important. As a higher education institute, the university should initiate and fund research based on sustainability, alternative energy, and other related topics that can bring direct benefits to the campus. The campus can be used as a testbed for different research, and pilot projects can be carried out using different elements of the campus.
• Campus-based environmental awareness activities: A university campus is a place that has different social and cultural activities happening throughout the year. Workshops, lectures, and debates about the contextual environment, resource protection, and preserving biodiversity should be made a common practice on the campus, encouraging its users to actively participate in protecting its existing resources and biodiversity and also change their behavior to ensure future sustainability.
• Co-operation: Incorporating other national international HEIs and public–private organizations to share knowledge and technology can accelerate the process of the end goal, which is a transition to a more sustainable and healthy future for the city and its dwellers. Developing the link with these organizations which share the same ideology and aim to protect the environment can strengthen the alliance of sustainability.