1. Introduction: Research Background and Purpose
To achieve the goal of limiting rising global average temperatures to just 1.5°C higher than pre-industrial levels, governments worldwide have placed growing emphasis on the need to transform urban systems in the pursuit of decarbonization. However, decarbonization efforts face numerous scientific, economic, political, and even social challenges. For example, European farmers have protested the European Union (EU)’s greenhouse gas (GHG) emissions reduction policies and rising electricity prices associated with the transition to cleaner forms of energy. As such, it is essential to approach decarbonization policies through the lens of a just transition—one that considers public acceptance and aims to ensure fairness and equity throughout the process.
In particular, while national plans typically focus on reducing emissions associated with the energy, power generation, and industrial sectors, is also crucial to address more localized emissions. These include emissions from commercial activity, as well as from the household, transportation, and waste sectors, which typically fall under the jurisdiction of local governments. Although direct industrial emissions dwarf direct emissions from the household sector, it is demand from the latter for food housing, travel, goods, and services that indirectly drives emissions in the former, as well as nearly all other sectors, including the energy, commerce, and waste sectors. Understanding emissions in this way is the essence of the carbon footprint (CF) framework.
Reducing carbon footprints in consumption sectors such as food, housing, transportation, and waste requires taking a two-pronged approach. The first task is to address spatial and structural issues that influence behavior. The second task is to address the behaviors themselves. Governments around the world are promoting carbon neutrality policies and pursuing decarbonization efforts, including South Korea and Germany. However, these two large, manufacturing-based economies differ markedly in terms of how far they have come with regards to the energy transition and the level of public awareness. This study is a product of efforts to better understand these differences, and the implications carried by its conclusions carry meaningful implications for urban planning policy designed to advance global decarbonization efforts.
This study aims to compare the acceptance of urban planning policies aimed at reducing the carbon footprint of the average household among Koreans and Germans. Based on this comparison, it identifies policy implications that can support the global pursuit of carbon neutrality. Figure ES1 below visualizes the structure of the report.
First, we review existing literature on carbon footprint (CF) reduction policies in Germany and Korea, including policies currently in effect. Second, we identify key planning elements for CF reduction in major consumption sectors, such as food, housing, and transportation. Third, we investigate and analyze public awareness of CF reduction policies and their acceptability. Finally, we present strategies for policy application based on a comparative analysis of survey results on levels of public awareness and policy acceptability in both countries.
2. Urban Planning Elements and Policies for CF Reduction
2.1 Theoretical background
The food, energy, and other resources consumed by city dwellers are almost always brought in from outside the city, which is why residents of urban areas often have relatively large carbon footprints (CFs). Since the oil crisis of the 1970s, urban planners have debated how to best reduce energy consumption and increase efficiency. Various theories have been proposed: center urban development around public transit, promote mixed-use neighborhoods, and encourage high-density development, among others. However, some studies have shown that some mixed-use and high-density development can actually increase residents’ CFs by affecting food consumption patterns.
Recently, scholars have begun to look at the relationship between various urban characteristics and carbon footprints, such as the difference in the CFs of single-person and multi-person households in the residential sector, the difference in CFs by season depending on the type of apartment, and the effect suburban sprawl on carbon footprints. As an actual example, the state of California in the United States maps the average CF of each household through a CF-based urban planning model. This data is used to establish spatial planning strategies for reducing greenhouse gas (GHG) emissions.
2.2 South Korea
In Korea, urban planning and CF reduction policies emphasize improving energy efficiency—through measures such as zero-energy building certification and the adoption of smart city technologies—expanding green infrastructure, and establishing sustainable transportation systems. These efforts support broader initiatives to cut GHG emissions and pursue carbon neutrality.
To guide these initiatives, key urban planning elements have been identified based on research that outlines principles and strategies for the integrated management of spatial and environmental plans at the municipal level, as well as specific planning techniques aligned with carbon neutrality objectives. One related study took a CF reduction inventory linked to regional carbon neutrality implementation strategies.
In examining policies for reducing CFs, we reviewed the GHG reduction strategy proposed by the Ministry of Environment, which accounts for differences in city types and characteristics. We also analyzed local government-level CF reduction policies identified in previous studies, categorizing them by sector and region. In addition, we explored why the concept of carbon neutrality has not been fully integrated into national land use plans, drawing on insights from various research reports on GHG reduction and carbon neutrality.
Our review also included implementation strategies from the Saemangeum Smart Waterfront City Carbon Neutral Master Plan, as well as programs related to energy transition, carbon sink expansion, resource circulation, climate change adaptation, and social transition found in carbon-neutral green city initiatives in Suwon and Chungju.
2.3 Germany
To examine the landscape of CF and GHG emissions reduction policies in Germany, we first reviewed the legal and policy foundations of CF reduction initiatives, CF-related urban planning measures, energy transition procedures, sector-specific reduction measures, and the level of public participation in urban planning processes.
Germany has set its climate protection goals in close alignment with the European framework, and has taken numerous measures to achieve these goals, including passing legislation, developing strategies, and establishing funding programs. The government is also closely monitoring developments for undesirable trends.
The multi-tiered German planning system and the existing strategies of the federal government all support efforts to achieve climate neutrality. Numerous basic principles and specific goals of spatial planning support the reduction of GHG emissions. Citizens can also influence planning processes at the municipal and neighborhood levels through participation processes. The data show that Germany has started to make real progress toward its climate goals, but that carbon neutrality remains a major challenge.
2.4 Key measures to reduce CF
To develop a list of key strategies for reducing CFs, we drew on the theoretical background, identified the major elements of CF reduction plans in Korea and Germany, surveyed relevant policies and case studies, and referred to international sources of relevant data, such as the United Nations’ (UN) 170 Actions for Climate Change Response and the Reduction Elements for a Green, Low-Carbon Built Environment.
To address limitations of the literature review, which relied on the research team’s existing knowledge, we used a large language model (LLM) to generate 25 draft statements designed to measure two aspects: the levels and types of awareness of CF-reduction urban planning, and the acceptability of CF-reduction related urban planning policies.
After collecting opinions from 20 experts on the validity of each item in the draft statements and the appropriateness of the Korean, English, and German expressions, we revised and supplemented them, ultimately arriving at a final set of 35 statements.
The statements were divided evenly into seven sector-based groups: overall CF reduction, food, housing, transportation, waste, sinks, and miscellaneous issues. The individual draft statements are related to one of three broad categories: planning and design; policies, programs, and business; and actions and initiatives. See Figure ES 2.
3. Measuring Perception Types and Acceptability of Key Measures to Reduce CF
3.1 Multilingual translation using LangChain
To ensure consistent understanding between South Korean and German respondents on statements measuring awareness and acceptability of carbon-footprint (CF) reduction strategies, a multilingual translation application was developed using LangChain, an LLM-based open source framework. For policy-related survey questions, we performed cross-language validation to ensure the consistency of results.
In the LangChain-based application, statements originally written in English were translated into Korean and German using LLMs such as ChatGPT-3.5, ChatGPT-4o, Gemini, Claude 3, and DeepL. These translations were then back-translated into English and evaluated using cosine similarity scores to assess how closely they matched the original text. The version with the highest similarity was selected as the most accurate translation.
To validate back-translated statements, linguists (experts) and native laypeople in both languages were consulted. Their evaluations were used to confirm whether or not the translated sentences accurately expressed the content of the statement.
3.2 Measuring perception types: Q methodology
The Q methodology was used to measure of major CF reduction strategies. Unlike expert-led decision-making techniques, such as the Analytic Hierarchy Process (AHP), the Q methodology is a qualitative-quantitative mixed methodology that is useful for systematically exploring the subjective views and judgment criteria of the general public. The Q Methodology can be used to identify the subjective judgment criteria of respondents that report different levels of acceptance across sectors and CF reduction factors. This makes it possible to pinpoint what kinds of perceptions and opinions to consider in the policy making process.
The 35 finalized statements as seen in Figure ES 2 were used in an 11-point Q classification survey, conducted both in-person and online with 40 total participants from Germany and Korea (20 from each country). The participants included experts in urban planning, the environment, and energy, as well as civil servants, private sector employees, and other members of the general public. The collected data were subjected to factor analysis through principal component analysis and varimax rotation using the PQ Method KADE program.
The Korean side categorized the survey data on policy acceptability into five perception types: expert-led (KR1), policy compliance (KR2), individual efforts (KR3), plan-centered (KR4), and government emphasis (KR5). The German side did the same, ultimately settling on four perception types: business-centered (DE1), regulatory preference (DE2), individual efforts (DE3), and green development (DE4). We then analyzed the commonalities and differences among these perception types and identified some of the basic characteristics of each type.
3.3 Measuring acceptability: Online survey
In order to measure the policy acceptability of CF reduction strategies, we administered an online survey based on a structured questionnaire. A population-proportional quota sampling was conducted to reflect the demographics of Korea and Germany. A total of 500 responses were collected (250 from each country).
The questionnaire included items on: awareness of and agreement with the CF concept; awareness of CF reduction strategies; and agreement with strategic CF reduction proposals in various sectors. In addition, the statements with the most/least agreement were selected in each sector, and the selected statements were prioritized again to identify differences in acceptability between key means of reducing carbon footprints. We then identified the statements with which respondents indicated the highest and lowest levels of agreement. These statements were reorganized to discern differences in acceptability between major CF reduction strategies. In addition, additional items were added to ask about the degree of implementation of activities to reduce consumption by carbon footprint reduction sector, social necessity, personal will, and realistic effectiveness. Additional questions were included to assess the extent of CF reduction in each sector, as well as perceptions of social necessity, personal willingness, and practical effectiveness. We also included questions on awareness of the energy transition and certain respondent characteristics, such as environmental awareness and social awareness, along with the level of understanding and support for carbon neutrality goals, the importance and performance of energy transition policies, and other questions related to the energy transition.
4. Key Findings and Policy Implications
4.1 Perception types and acceptability in South Korea and Germany
For the main analysis of the study, we explored the similarities and differences in perception types between South Korea and Germany across several dimensions: approaches to CF reduction, the roles of government, companies, and individuals, attitudes toward renewable energy, and willingness to bear economic burdens. While some perception types exhibited similarities—particularly in relation to the roles and levels of intervention by each actor—many notable differences also emerged.
By perception type, Korean responses were fairly balanced across the board, and no one perception type was overrepresented. Individual efforts (KR3, 29.2%), government emphasis (KR5, 22%), and expert-led (KR1, 21.2%) were the top three. In contrast, German perception types were more clustered, with green development (DE4 46.8%) ranking first, followed by individual efforts (DE3, 33.2%).
The statistical differences between CF reduction strategy-related survey items measured on the Likert scale were compared using a t-test between Korean and German respondents. Korean respondents exhibited a higher level of agreement on the CF concept and the need to reduce consumption activities, but Germany had a higher level of awareness of CF reduction strategies.
Comparing average acceptability by sector, we observed notable differences between Korean and German respondents. However, we observed no significant differences in opinions on practical measures such as reducing personal food consumption (#8), promoting zero-energy buildings in the residential sector (#15), reducing personal consumption (#1), and reducing waste (#21). In comparing acceptability rankings by sector, Korean respondents indicated they agreed the least with the need to reduce their personal carbon footprint (#1) and food consumption (#8). Coincidentally, these were among the items for which German respondents indicated a high level of agreement. The items with the highest levels of agreement varied. For Korean respondents, the most widely accepted items were the role of government in addressing overall CF (#3) and the role of companies in the production process (#24). In contrast, German respondents showed the highest acceptability for voluntary individual actions in the waste (#21) and household (#13) sectors. The item with the lowest level of agreement in both countries was the proposal to increase electricity rates (#35).
In conclusion, we find significant differences in perception types between Germany and Korea. This well illustrates the need for customized approaches to carbon footprint reduction policy and carbon footprint awareness-raising strategies. Our findings suggest that public policy should consider the specific characteristics of each perception type, and attempt to strike a balance between the appropriate roles of companies, the government, and individuals. Meanwhile, Korea and Germany show differences in their approaches to CF reduction, and it was confirmed that the social and cultural backgrounds of each country have a significant impact on policy acceptance.
4.2 Policy recommendations for CF reduction
Based on the Q methodology and the results of the survey analysis, we propose that policymakers in both Korea and Germany should consider the composition of perception types in each country identified in this study when setting overall directions for CF reduction policies. Figure ES 2 shows where Koreans and Germans agreed and disagreed with regards to CF reduction strategies. These findings carry the following implications for policy.
When comparing consensus and distinguishing statements across perception types in each country, we can see differences in policy acceptability, the differences in attitudes toward the appropriate roles of government, companies, and individuals, approaches to environmental protection, major policy tools, financial support methods, social acceptability, and community roles, as shown in Table ES 1. We can also confirm that responses from both countries indicated a resistance to policies that imply a significant economic burden.
Based on our comparison of policy receptivity in Korea and Germany, we categorized CF reduction policy strategies into five groups: 1. Strengthening government-led policies and providing incentives, 2. Accelerating the transition to eco-friendly transportation, 3. Reinforcing circular economy initiatives in the waste sector, 4. Expanding carbon sinks and urban green space, 5. Taking a cautious approach to electricity rate hikes. See Table ES 2 for key priorities and recommendations.
In order to enhance the implementation of CF reduction policies, it is necessary to ensure that CF reduction plans and policies stand on sound legal and institutional footing. We propose several measures to incorporate CF reduction planning elements and policies into Korea’s legal and institutional framework, as outlined in Table ES 3.
These measures include revising guidelines for establishing environmental plans at the basic local government level, developing implementation plans under the Framework Act on Carbon Neutrality and Green Growth for Coping with Climate Crisis and national land and environmental plans, and revising the draft of the Fifth National Comprehensive Territorial Plan (2020-2040).
5. Conclusion
This study holds both academic and policy significance by presenting a rigorous analytical methodology and highlighting the importance of stakeholder identification based on different types of awareness and acceptability related to urban planning and policy implementation for reducing carbon footprints. Future research should build on these findings through deeper analysis, such as examining the interactions among policy acceptability factors to support the development of more tailored and effective CF reduction policies.