4.1 Descriptive analysis of the data
4.1.1 Annual research output overview
Figure 2 demonstrates the recognition of climate change in PPP infrastructure projects in the 1990s. In 1996, Topping et al. (1996), published an article on the relevance of adopting PPP in fighting climate change in the Asian-Pacific Region, with much emphasis on the built environment. In the 2000s, two articles were published in 2001 and 2005. The first half of the 2010s up to 2015 saw an increment in research outputs from two to eight articles. The growth in publications tripled from eight to thirty-two articles in the second part of the 2010s to 2022. An indication of an increase in the interest in studies on climate-smart policies in PPP projects among the scientific research community is a key driver of the growth in publications. Moreover, this is an emerging research area with promising opportunities for future research, given the few existing studies (Owusu-Manu et al. 2020a). The growth in the research is also driven by the demand from policymakers and practitioners to gain an understanding of the climate-related issues to institute steps or actions to achieve the United Nations’ SDGs 13 – which is the climate action (Omer &Noguchi 2020). Finally, the increased academic interests and the need to implement climate agreements such as Paris Climate Agreement and COP26 are motivating research works on this topic (Cheng et al. 2021).
4.1.2 Geographical Analysis
In terms of contribution by countries and regions, this section of the review focuses on tracking relevant research outputs based on the geographical occurrence of the studies. Table 2 presents those 20 studies that covered multiplenations (48.84%). Multiple nations in this study’s context refer to a study that was conducted with research data from more than one country. This shows the global interest in climate change research and can be attributed to the rapidly occurring negative impacts of extreme climate change and increased concerted intergovernmental efforts to countermeasure its consequences. Specific regions like Asia reported eleven studies (25.58%), Europe and North America with four studies (9.30%) each. Two studies (4.65%) were produced by the Australia & Oceania, and South America continents respectively. (2.33%). Notably, countries in the African continent are missing from Table 2. Even though climate change affects developing economies like Africa, little effort has been made to fight the climate risks on the continent (Akomea-Frimpong et al. 2021d). Overall, the results of this section demonstrate the inadequate application of PPP in curtailing the consequences of climate change with few individual countries featured in Table 2.
Table 2
Contribution by countries (and sub-regions)
| Continent/Region | Countries | Articles |
| Multi-nations | Two or more countries | 20 |
| Asia | China, Nepal, Pakistan, India, Bangladesh | 11 |
| Europe | Denmark, Finland, Iceland, Norway, Sweden | 4 |
| North America | USA (United States of America), Canada | 4 |
| Australia & Oceania | Australia, Samoa | 2 |
| South America | Brazil | 2 |
4.1.3 Influential publishers (Journals)
The forty-three (43) research papers used in this study appeared in 32 peer-reviewed journals. The leading journals include Sustainability (Switzerland) and Environment and Planning C: Government and Policy, with seven and three articles, respectively. This was followed by Built Environment Project and Asset Management, Land Use Policy, and Global Environmental Change with two articles each. The journals with more than one articles constitute 18.75% (i.e., 6/32) of the most cited journals. In addition, an h-index from reputable bibliographical journal ranking sites was included in Table 3. The aim of showing the h-index was to demonstrate the statistical metric impact of the scholarly articles on this subject matter (Wuni et al. 2019). The h-index measures the number of publications within a journal to the number of citations of the publications (Adabre et al. 2021). The threshold of inclusion of a journal in this study was a journal with at least 20 metric scores that fall within the Q1 and Q2 ranking spectrum. In summary, Table 2 displays highly impactful journals such as Renewable and Sustainable Energy Reviews with an h-index of 295, Journal of Hydrology, Energy Policy, and Journal of Cleaner Production with 226, 217, and 200 h-indexes, respectively. Global Environmental Change was the fourth most cited, with two papers and an h-index of 177. Geoforum, Current Opinion in Environmental Sustainability and Sustainability were highly cited with an h-index above 80.
Table 3
Most cited journals and H-index
| No. | Journal | Number of Articles | H-index |
| 1. | Sustainability (Switzerland) | 7 | 85 |
| 2. | Environment and Planning C: Government and Policy | 3 | 69 |
| 3. | Land Use Policy | 2 | 115 |
| 4. | Global Environmental Change | 2 | 177 |
| 5. | Built Environment Project and Asset Management | 2 | 21 |
| 6. | Renewable Energy | 2 | |
| 7. | Journal of Cleaner Production | 1 | 200 |
| 8. | Journal of Outdoor Recreation and Tourism | 1 | 21 |
| 9. | Arabian Journal of Geosciences | 1 | 48 |
| 10. | Renewable and Sustainable Energy Reviews | 1 | 295 |
| 11. | Global Food Security | 1 | 46 |
| 12. | Arabian Journal for Science and Engineering | 1 | 43 |
| 13. | Energy Policy | 1 | 217 |
| 14. | Technological Forecasting and Social Change | 1 | 117 |
| 15. | Development Southern Africa | 1 | 41 |
| 16. | SN Applied Sciences | 1 | 52 |
| 17. | Environmental Sciences Europe | 1 | 35 |
| 18. | Economies | 1 | 11 |
| 19. | Sustainability Accounting, Management and Policy Journal | 1 | 29 |
| 20. | Climate Policy | 1 | 66 |
| 21. | Sustainable Development | 1 | |
| 22. | Agricultural Economics (United Kingdom) | 1 | 82 |
| 23. | Urban Climate | 1 | |
| 24. | Journal of Health Management | 1 | 17 |
| 25. | Current Opinion in Environmental Sustainability | 1 | 87 |
| 26. | International Journal of Climate Change Strategies and Management | 1 | 21 |
| 27. | Geoforum | 1 | 116 |
| 28. | Journal of Construction Engineering and Management | 1 | |
| 29. | Professional Geographer | 1 | 75 |
| 30. | Economic Research | 1 | |
| 31. | Environment and Urbanisation-ASIA | 1 | |
| 32. | Journal of Hydrology | 1 | 226 |
4.1.4 Dominant research techniques
Figure 3 presents the distribution of the 43 relevant studies per the dominant research method. These articles vary in terms of data collection and research analytical techniques. Even though some studies employed more than one method, the dominant research method was the case study approach. Eighteen articles used case studies representing 41.86% of the studies. With the increasing interest in climate change in corporate practice and academia, pertinent issues related to climate change are examined on a case-by-case basis to know its effects on the environment (Ford et al. 2010). Case studies provide well-tailored solutions to climate risks with in-depth analysis and recommendations (Hunt &Watkiss 2011). Next, eight studies examined climate change in PPP projects with statistical models representing 18.60%, whiles 16.28% utilized focus group discussions to unravel issues on climate change in the PPP projects. Interviews were used in five studies and three research outputs were based on surveys. Harris et al. (2021) and Akomea-Frimpong et al. (2021b) mentioned that interviews and surveys feature prominently in construction management studies. Lastly, only two studies were reviewed studies utilizing institutional reports and project documents.
4.1.5 Research funding sponsors
In Table 4, the information on the funding agencies that support the studies on climate change in PPP infrastructure projects is presented. More than half of the studies were sponsored by governmental and intergovernmental organizations that aim to address climate change in public infrastructure projects. Such research sponsorship has garnered interest among researchers in the PPP domain because of the financial and technical support they receive from the funding agencies. The research of Karlsson-Vinkhuyzen andVan Asselt (2009) was financed by the Director-General (DG) Research and Innovation of the European Commission to assess measures to manage climate change in achieving clean infrastructure development within the Asia-Pacific Partnership region. The agency also funded Pattberg (2010) research. China, Canada and Sweden gave financial support to five, two and two studies, while the rest of the sponsors in the countries listed in Table 4 supported one study each. In particular, the Biodiversity and Ecosystem Services in a Changing Landscape (BECC) of Sweden and the Knowledge Foundation (KK-Stiftelsen) funded two studies in 2012 and 2021, respectively. Eleven (11) studies received funding from countries within Europe. This shows the level of interest in issues of climate change and PPP in Europe. The rapid effects of global warming have put the resilience of infrastructure projects at stake, with rising cases of floods and fires (Dwivedi et al. 2022). The outcomes call for concerted efforts to support climate action and fund research to minimize the climate change risks in PPP projects.
Table 4
Sponsoring and Funding Agency
| Country (Type of Funding) | Country/Region | Articles |
| DG Research of the European Commission | Europe | 2 |
| Austrian Climate Research Programme (ACRP) | Austria | 1 |
| BECC (Biodiversity and Ecosystem Services in a Changing Landscape)-Sweden | Sweden | 1 |
| Aalto University | Finland | 1 |
| Natural Resources Canada | Canada | 1 |
| National Natural Science Foundation of China | China | 2 |
| National Science Foundation (Pacific Institute for Climate Solutions) | Canada | 1 |
| HUDCO’s Human Settlement Management Institute | India | 1 |
| FORWIND and LERFOB - INRA (French National Institute of Agronomic Research) | Germany, France | 1 |
| European Union | EU (European Union), Swiss | 2 |
| Office for Coastal Management, National Oceanic and Atmospheric Administration | USA | 1 |
| CSIRO Climate Adaptation Flagship. | Australia | 1 |
| Hong Kong PhD (Participants Had Doctor) Fellowship Scheme from the Research Grants Council (RGC) | China | 1 |
| Erasmus Mundus Action (Experts4Asia) and RECETOX Research Infrastructure | EU, Czech Republic | 1 |
| United Nations Development Programme | Bangladesh | 1 |
| BBI-JU secretariat (EU) | Europe | 1 |
| COMSATS University Islamabad | Pakistan | 1 |
| Knowledge Foundation (KK-Stiftelsen)- grant number (2019 − 0129) | Sweden | 1 |
| Hebei Social Science Foundation | China | 1 |
| National Natural Science Foundation of China; and the Youth Program of National Natural Science Foundation of China. | China | 1 |
4.1.6 Document citation analysis
Citation analysis reveals an article’s impact in a study area (Kukah et al. 2021). Table 5 shows the top most cited articles with more than 30 citations showing the influential and productive studies on climate change and PPP projects. Pattberg (2010) and Bauer et al. (2012) are highly referenced by other studies with 126 and 109 citations. The third most influential was Karlsson-Vinkhuyzen andVan Asselt (2009), with 67 citations. Their study explained the collaborative efforts of the Asia-Pacific Partnership to promote clean energy, development, and control the consequences of climate change in Asian countries. McGee andTaplin (2009) further provided lessons other nations (and sub-regions) can take from the Asia Pacific Partnership in ensuring climate action. That study has received 66 citations as of 2021. The last three studies of Wong et al. (2012), Lövbrand andStripple (2012), and Buso andStenger (2018) carry similar themes on mitigation, adaptation, resilience, and a mixture of the three key themes on climate change in PPP infrastructure development.
Table 5
List of impactful articles in PPP/Climate Change Research
| Article | Research Focus | Citations |
| Pattberg (2010) | PPP in transnational climate governance, Resilience | 126 |
| Bauer et al. (2012) | Multi-level climate governance, Mitigation, Adaptation | 109 |
| Karlsson-Vinkhuyzen andVan Asselt (2009) | Asia-Pacific Partnerships, climate action, Resilience | 67 |
| McGee andTaplin (2009) | Ecological modernization, Resilience, Adaptation | 66 |
| Forsyth (2005) | Climate change policies, waste-to-energy, capacity building | 64 |
| Zhang andMaruyama (2001) | Clean development mechanism, financing climate projects | 59 |
| Harman et al. (2015) | Climate adaptation and urban partnership, mitigation | 53 |
| Wong et al. (2012) | Climate change adaptation in tourism, climate action | 33 |
| Lövbrand andStripple (2012) | Carbon markets volatility, global climate action | 33 |
| Buso andStenger (2018) | Policy response, Energy efficiency, mitigation | 33 |
4.1.7 Sectorial analysis
The results in Fig. 4 show sectors of PPP arrangements where climate action has gained attention. They include construction (25.58%), transport (4.65%), ecology/environment (4.65%), technology (4.65%), energy (11.63%), water and sanitation (4.65%), agriculture (4.65%), generic (27.90%), education (2.33%), health (2.33%), tourism (2.33%), and oil and gas (4.65%). Most of the studies conducted were generic, covering a wide range of sectors. For instance, Juhola (2013) and Lange et al. (2021b) investigated the sustainability, circular economy, and adaptation to climate change in the environmental preservation of projects across many sectors. Climate-smart studies were specifically conducted on sectors like the energy, transport, and construction sectors: Desai et al. (2016), Ahmad andRaza (2020), and Anwar et al. (2021), respectively.
4.2 Key factors driving climate-smart solutions in PPP infrastructure projects
In this section, Table 6, seventeen drivers of climate action in the PPP industry are presented with comprehensive discussions.
Table 6
A list of factors influencing climate change policies in PPP infrastructure projects
| Code | Drivers/Influencing factors | References (refer to the appendix) |
| KD1 | Recent climate change summits (2015 Paris Climate summit and COP26 in 2021) | 1, 2, 3, 5, 8, 12, 13, 15, 16,, 18, 19, 20, 22, 23, 27, 28, 29, 30, 31, 33, 34, 35, 36, 38, 41, 43 |
| KD2 | The quest to achieve UN SDGs goals/targets by 2030 | 2, 5, 6, 8, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 29, 30, 31, 33, 35, 38, 39, 41, 43 |
| KD3 | National targets on climate change | 1, 2, 10, 12, 13, 16, 17, 18, 21, 22, 23, 24, 25, 26, 27, 28, 29, 31, 32, 34, 35, 37, 38 |
| KD4 | Demand for smart cities and public facilities | 1, 4, 11, 12, 14, 16, 19, 20, 21, 23, 25, 26, 27, 29, 31, 32, 33, 34, 35, 42, 43 |
| KD5 | Acceleration of economic development | 1, 3, 4, 5, 8, 9, 17, 19, 22, 23, 24, 25, 28, 29, 32, 33, 37, 38, 39, 40, 41 |
| KD6 | Green infrastructure revolution | 1, 4, 14, 15, 16, 17, 19, 20, 24, 25, 26, 27, 28, 29, 33, 35, 43, 44 |
| KD7 | Consumption of renewable energy | 3, 5, 8, 9, 12, 17, 18, 19, 20, 27, 28, 29, 32, 38, 41, 43 |
| KD8 | Protecting/preserving the environment | 1, 3, 6, 7, 8, 12, 20, 21, 22, 24, 25, 26, 27, 28, 29 |
| KD9 | Integration of climate-smart policies in urban infrastructure planning | 2, 10, 16, 18, 19, 26, 28, 31, 38, 39, 40, 43 |
| KD10 | Job opportunities in a low-carbon economy | 1, 9, 10,12, 19, 20, 22, 23, 25, 29, 36 |
| KD11 | Advancement in technology, innovation, and knowledge on climate change | 1, 10, 15, 16, 20, 32, 35, 38, 42 |
| KD12 | Public participation, inclusion, and support | 2, 4, 6, 8, 18, 21, 32, 39 |
| KD13 | A shift towards social sustainability | 12, 23, 24, 37, 38, 40, 42 |
| KD14 | Population growth and anthropogenic activities | 12, 23, 31, 35, 39, 42 |
| KD15 | Availability of climate funding | 2, 21, 26, 27, 38, 43 |
| KD16 | Reassessment of policies in the current infrastructure sector | 12, 20, 28, 31, 32, 41 |
| KD17 | Acceptance of climate change mitigation and adaptation strategies | 3, 12, 15, 19, 22, 34 |
Recent climate change summits (2015 Paris Climate summit and COP26 in 2021)
In recent times, there has been an increase in treaties and agreements to combat climate change in achieving SDGs (Buso &Stenger 2018, Lee et al. 2021). This has triggered many partnerships to bolster the attainment of set goals in terms of financial resources and expertise. International summits such as Paris (France) Climate Conference in 2015 and Glasgow Climate Conference in 2021 have been avenues to deliberate and come up with targets in the fight against climate risks globally (Jacobs 2022). In such summits, politicians and influential organizations (both public and private) meet to agree on measures to combat climate change. Such summits are having trickling down effects on project managers in the infrastructure sector to design and implement policies to achieve climate targets (Depledge et al. 2022).
The quest to achieve UN SDGs goals/targets by 2030
The United Nations’ SDGs establish clear goals and action plans to adapt to and mitigate climate change to achieve resilient infrastructures (Dwivedi et al. 2022). Climate actions that are found in UN SDGs 9 and 13 provide a detailed framework to minimize climate risks and maintain robust infrastructure against unforeseen disasters. The PPP arrangement through SDGs 17 advocates for the partnership of stakeholders to reduce carbon emissions and the consequences of climate change in SDGs 8, 9, 11, and 13 (Ahmad &Raza 2020).
National targets on climate change
To meet international targets on climate change, many nations are framing and implementing policies to cut down emissions in all sectors, including the infrastructure sector. This climate action has influenced project managers and key stakeholders in the construction and infrastructure sector to reassess and align existing project policies to the national climate targets. Policy alignment has been in the spotlight in recent times, as it is a quick way of adapting to climate change and enforcing climate policies and models in PPP projects. For instance, the World Bank has opened a portal of a plethora of information and policies together with climate toolkits to support the alignment of climate policies into PPP infrastructures around the world (PPPLRC 2022). With the pre-amendment of policies for sustainability and resilient cities, governments and policymakers are encouraging public-private partnerships between the private sector and public institutions to arrive at zero emission targets by 2050 (Anwar et al. 2021, Jayasuriya et al. 2020). The long-term goal of embracing PPP arrangements in the fight against extreme climate change is to support the resilience and sustainability goals and reduce public debts on infrastructure projects, especially in developing economies.
Demand for smart cities and public facilities
To curtail the impact of climate change and construction waste, new policies and high demand have surfaced at the national level and construction industries to create sustainable cities while increasing infrastructure development (Lange et al. 2021b). Increased urbanization calls for more green space and affordable housing (Tian et al. 2022). Smart cities enhance the usage and sharing of information on infrastructures, including fluctuations in climatic conditions. Hence, the early involvement of PPP guarantees the achievement of these technological and social development needs (Somokanta 2022).
Acceleration of economic development
Global industrialization has birthed the need to establish resilient economic policies to eliminate the negative social and ecological balance. According to Mahat et al. (2019), although industrialization enhances economic growth, it has an adverse effect on the environment by using non-renewable energy, giving off carbon emissions, among others. This, in the end, has a dominant effect on human health (Yang et al. 2022). Therefore, in recent years, city resilience has become a top priority with the prime motive of reducing carbon emissions and sustainable jobs. It is, therefore, not surprising to notice countries and world leaders establishing resilient economic policies to promote infrastructure development in accordance with minimizing the risks presented by climate change (Maraña et al. 2020). Although resilient economic policies can be expensive to implement, climate change mitigation and resilience actions (strategies) are activators for private investments in the infrastructure sector to cushion economic development in emerging markets (Taylor &Harman 2016).
Green infrastructure revolution
The increment in carbon emissions in infrastructure development in the early 2000s and its resultant effect on the climate has shifted governments and industry practitioners to focus on a low-carbon economy (Ahmed et al. 2020). This has increased urban partnerships to bolster low-carbon infrastructure. The successful implementation of these low-carbon PPP projects is currently prevalent in developed economies (Chen et al. 2022). However, governments and public investment in infrastructure projects have soared in developing economies in the last decade (Liu &Jensen 2018). World leaders are determined to attain low-carbon economies to improve human health and social equality by establishing and supporting low-carbon PPP projects in the sustainable environment of emerging economies.
Consumption of renewable energy
Most countries have pledged to reduce greenhouse gases and carbon emissions with set targets to be achieved by 2025 to 2030 (Fleta-Asín &Muñoz 2021). Transforming to a low carbon economy requires investment in energy-efficient and renewable sources of infrastructure. With the aid of PPP arrangements, private investments in low energy have increased, resulting in low investment in energy-consuming public buildings (Hall et al., 2017). The involvement of private partnerships promotes an alternative mode of supplying energy infrastructures to society in comparison to hydroelectric power. According to Lange et al. (2021a), focusing on high-value end-products through the production of renewable energy such as biomass, solar, and wind energy has improved innovation, fostered economic development, and enhanced the livelihood of individuals of humanity.
Protecting/preserving the environment
Environmental sustainability strategies are on the rise to preserve our environment from the impact of climate change (Allam &Jones 2019). Climate and environmental activists have tabled the need to protect the environment with heavy investments and partnerships from all stakeholders. Environmental protection can then be achieved while being consistent in implementing and practicing renewable materials for construction that contribute to a healthier ecosystem (Cui &Huang 2018). Fostering economic growth and development is essential in enhancing green strategies through partnerships to enhance environmental sustainability. Climate activists advocate for green growth policies in the construction sector that are concerned with the progress of the natural environment (Buso &Stenger 2018). Creative collaborations between governments and private organizations enhance the restoration of the ecological balance of cities through effective adaptation and mitigation strategies (Desai et al. 2016, Harman et al. 2015).
Integration of climate-smart policies in urban infrastructure planning
To create pace with the increased population and thriving economies, urban infrastructure is underway, with much focus on urban transport and emissions (White &Wahba 2019). Climate change policies are being promoted among PPP project managers with both local and international support. This perpetuates the need for private capital to be mobilized urgently for sustainable redesigning of urban infrastructure that is climate resilient (Maraña et al. 2020, Zhang et al. 2018).
Job opportunities in a low-carbon economy
Focus on low-carbon infrastructure has been seen as a threat to the job market within the fossil fuel industry. Juhola (2013) argues that low-carbon infrastructure improves the economic and social livelihoods of individuals. Job creation is a key outcome of low-carbon PPPs that instill a sense of urgency in private companies, particularly multinational organizations, to employ climate experts to manage the consequences of climate change. Partnerships relating to building low-carbon infrastructures propel the ability to resolve issues of funding large-scale projects while employing local citizens to better the economic livelihood of people (Beery 2018).
Advancement in technology, innovation, and knowledge on climate change
In achieving a long-lasting solution to climate change, technological innovation is critical. The private sector is increasingly interested and committed to collaborating with various partners to promote early deployment to enter new markets through technology and financial support and regulations to overcome specific barriers to climate risks (Karlsson-Vinkhuyzen &Van Asselt 2009, Lee et al. 2021). Ahmad et al. (2020) further state that project managers must use innovative technologies in the infrastructure sector to promote energy-efficient outcomes with knowledge about renewable energy, as this is the only way to replace outdated technologies with more energy-efficient infrastructures (Wang et al. 2021b). Inadequate awareness and knowledge of human-inspired climate change have resulted in industrial disposal, bank erosion, excessive water withdrawal, and salt intrusion (Cioffi et al. 2020). Various interventions, from the usage of social media to counter disinformation, will be an addition to the fight against climate change in the construction sector (Saha et al. 2020).
Public participation, inclusion, and support
A key focus area in attaining sustainable infrastructure is incorporating citizen engagement and social cohesion into city resilience-building policies (Maraña et al. 2020). Most of the challenges of sustainable infrastructure can be resolved by involving all stakeholders who are affected by climate inaction, such as private individuals and residents in public facilities (Garschagen &Sandholz 2018). These participations help in making multi-dimensional strategies and decisions to manage the climate crisis in the infrastructure sector.
A shift towards social sustainability
Climate change impacts human societies. There are evidences to show that climate crisis pose negative impacts on economic and social activities (Allam &Jones 2019, Fell &Mattsson 2021). Thus, efforts are being made to attain social sustainability while responding to climate change via multi-stakeholder collaborations (Osei-Kyei et al. 2019). In addition, social and societal well has been labeled a key element of the SDGs. Infrastructure challenges can be attributed to rapid urbanization (Desai et al. 2016). The global population is increasingly residing in cities. Cities housed more than 59.5% of the world's population in 2019, and projections indicate that 70% of people will live in cities by 2030 with social problems from heatwaves and the cooling of buildings (Harris et al. 2020). Furthermore, cities are presently under pressure to deal with a variety of social challenges, from climate risks to mental and physical health problems (Jayasena et al. 2020). This demographic transition, which is accompanied by rapid urbanization, corresponds with the challenges of urban infrastructure development, such as water supply, drainage, solid waste disposal, roads, transportation, and housing influenced by climate change (Bauer et al. 2012).
Population growth and anthropogenic activities
According to the United Nations’ Department of Economic and Social Affairs (UN DESA), over two million people will be added to the world’s population by 2050. Population spikes and human activities such as farming, mining, and non-renewable energy are projected to impact the ecosystem negatively (Ahmed et al. 2020, White &Wahba 2019). Rapid population growth also affects water resources and land use in the context of climate change. To preserve the environment and promotes sustainable infrastructure, private partnerships are on the rise in achieving managing population growth and human activities that endanger the planet. There is increased awareness of the adverse impact of climate change among policymakers, experts, authorities, and health departments to establish and enforce sustainable policies to adapt to climate change (Fell &Mattsson 2021, Jacobs 2022).
Availability of climate funding
The demand for climate finance that promotes financial investments from the private sector is increasing for the built environment (Akomea-Frimpong et al. 2021a). Some developed nations have been involved in providing climate finance to low-income and developing countries to ensure a reduction in carbon emissions (Bisaro &Hinkel 2018). These contributions are instruments that supplement resources in the construction industry and serve to fund climate-resilient and low-carbon projects (Mahat et al. 2019). Sustainable infrastructure development and investments have traditionally been viewed as a government responsibility (Allam &Jones 2019, Buso &Stenger 2018). However, financial resources are critical for any country to achieve a low-carbon transition has received the financial support of private investors in recent years (Ahmad and Raza, 2020: Hall et al. 2017). The use of PPP financing arrangements further ensures efficient and fair distribution of risks and incentives among public and private actors to meet climate targets (Choi et al. 2021).
Reassessment of policies in the current infrastructure sector
Many infrastructure projects have started policy reassessment and reforms to achieve a green economy. This includes setting up institutional mechanisms and policy instruments to stimulate climate adaptation change in the old-fashioned roads, schools, and public houses (Kaminsky 2022). As a policy instrument, the PPP arrangement ensures the reassessment of new projects to ensure cost-efficiency and produces versatile long-term benefits (Somokanta 2022, Wang et al. 2022). The reassessment encouraged the involvement of private investors and government interventions in providing subsidies for climate action in sustainable infrastructures.
Acceptance of climate change mitigation and adaptation strategies
Mitigation and adaptation policies have been used widely to fight climate change invariably (Lee et al. 2021). Most industries have received technical support for facilitating these policies. As a result of climate change, a huge portion of a country's GDP (Gross Domestic Product) is diverted to public expenses on mitigation measures and adaptation initiatives (Allam &Jones 2019). Further, project management organizations are also drafting strategies to manage climate change. The total involvement and support from private partnerships are facilitating the transition to low-carbon emissions to resolve the climate crisis (Pinilla-De La Cruz et al. 2022).
4.3 Barriers to the implementation of climate-smart solutions in PPP infrastructure projects
Table 7 and the discussions that follow demonstrate the major challenges to the adoption and implementation of climate-smart policies in PPP projects.
Table 7
Dominant barriers to reducing climate risks in PPP projects.
| Code | Critical Barriers | References (refer to appendix) |
| CB1 | Heavy reliance on fossil fuel energy | 1, 5, 9, 11, 14, 15, 16, 18, 19, 22, 23, 24, 25, 27, 30, 31, 32, 33, 34, 36, 39, 40, 43 |
| CB2 | Policy gap and misalignment | 1, 2, 3, 4, 5, 6, 7, 8, 9, 13, 14, 17, 18, 19, 23, 24, 28, 33, 37, 39, 42 |
| CB3 | Excessive pressure on urban infrastructure | 1, 2, 6, 7, 8, 9, 13, 15, 18, 19, 24, 27, 32, 36, 37, 38, 39, 40, 43 |
| CB4 | Financial constraints | 1, 2, 6, 7, 8, 9, 13, 15, 17, 21, 22, 23, 30, 31, 36, 37, 38, 42 |
| CB5 | Lack of political will | 4, 8, 12, 15, 16, 18, 20, 22, 25, 27, 29, 30, 32, 35, 37, 42 |
| CB6 | Poor legal environment | 6, 7, 8, 9, 13, 14, 15, 16, 19, 24, 27, 30, 31, 34, 37, 38 |
| CB7 | Inadequate technology development and transfer | 6, 7, 8, 9, 13, 15, 17,18, 19, 21, 35, 36, 37, 38, 41 |
| CB8 | Ineffective climate risk management | 5, 6, 7, 8, 9, 12, 14, 15, 18, 19, 22, 24, 26, 36 |
| CB9 | Managerial costs | 2, 5, 6, 7, 8, 10, 11, 15, 18, 19, 21, 22, 27, 36 |
| CB10 | Lifecycle wastes and lapses in embracing circular principles | 6, 7, 8, 9, 12, 13, 15, 18, 19, 20, 24, 26, 27 |
| CB11 | Insufficient stakeholder participation/involvement | 6, 7, 8, 9, 15, 18, 19, 20, 36, 37, 38, 43 |
| CB12 | Scarcity of climate-smart resources | 5, 6, 7, 8, 9, 15, 18, 19, 36, 37, 38 |
| CB13 | Sustainability and maintenance of PPP infrastructure | 6, 7, 8, 9, 15, 21, 22, 23, 36 |
| CB14 | Information and awareness gap | 6, 7, 8, 9, 15, 18, 19, 36 |
Heavy reliance on fossil fuel
According to Lo andChen (2020), despite the soaring renewable capacity of most developed economies, They still depend heavily on fossil-fuel power for economic activities. This high dependence on fossil fuels is a substantial contributor to the present level of worldwide greenhouse gases (Topping et al. 1996). Fossil fuels and products are cheaper, and nations generate large revenues from their exports. One sector that depends on fossil fuel products in the form of crude oil and its associated by-products is the mainstay of the transport infrastructure (Jacobs 2022). Although there have been increased global efforts to shift this dependence to renewable energy sources, most countries continue to choose and depend on fossil fuels for their energy supply and the development of infrastructure projects (Choi et al. 2021).
Policy gap and misalignment
From the review, policy misalignment to national and international policies in the PPP industry is a challenge to building climate-smart (zero-carbon) infrastructures. The economic, social, and environmental policies of the project managers do not match with climate pacts. Existing industrial activities of construction, manufacturing, and transport sectors in advanced countries, for instance, according to Anwar et al. (2021), are known to be contributors to social and ecological imbalances. The United Nations Development Programme’s report on China in 2020 indicated that the misalignment of industrial policies to address large volumes of carbon emissions is expected to hinder the achievement of SDGs (Yang et al. 2021). Regardless of the financial status of a nation, a gap in policy implementation renders any climate action inactive. According to Zhang et al. (2018), a gap in policy implementation has blocked the effective implementation of managerial policies toward climate action in the construction industry. Policy implementations are the responsibility of all stakeholders through responsible groups, agencies, institutions, and organisations. However, it was evident from literature that inadequate capacity-building for designing and applying climate change control measures is amplifying policy misalignment schemes in PPP projects (Lo &Chen 2020). Capacity development, according to Saha et al. (2020) is one of the few essential components of strong public-private partnerships to align and countermeasure climate risks. Inadequate institutional capacity to meet climate targets contributes to the increasing vulnerability of several communities and ecosystems by limiting their adaptive capacity to climate change (Mahat et al. 2019). Several nations are behind the implementation of climate policies in PPP projects due to unclear-cut of institutional structures and policies to adapt and mitigate climate change (Pörtner et al. 2022).
Excessive pressure on urban infrastructure
With the rapid rural-urban migration taking place across the globe, pressure on the urban infrastructure has heightened, necessitating an urban agglomeration leading to construction activities and the release of carbon emissions that threatens the climate (Tian et al. 2022). This challenge is reflected in rising carbon dioxide (CO2) levels in urban areas. Low-carbon projects require huge financial investments as compared to conventional projects, which many nations are not ready to invest in climate-resilient projects (Harman et al. 2015). Pressure for urban infrastructure coupled with an inflated cost of climate-responsible infrastructure results in the swapping of climate-smart policies in PPP projects to carbon-emission concentration infrastructures with the goal of meeting the growing demands for more infrastructures. Particularly in developing countries and growing PPP markets, the increased need for amenities, shelter and infrastructure investment is perceived as outweighing the necessity for environmental protection (Allam &Jones 2019). As an alternative for many nations, the pressure to meet the growing demand for public facilities makes development partners place less emphasis on measures to minimize climate change.
Financial constraints
Building low-carbon PPP projects have higher financing costs (Jensen &Dowlatabadi 2018). This is evident in most of the review papers that lamented the costs of implementing and monitoring climate-change policies in PPP infrastructure projects (Bauer et al. 2012, Buso &Stenger 2018). The development of low-carbon infrastructure requires huge financial investments as compared to conventional projects (Hall et al. 2017). The financing of these vital climate change mitigation initiatives requires significant economic inputs, which developing countries often find difficult to provide (Allam &Jones 2019). Climate-smart infrastructure funding and finance is a big undertaking, and there is an increasing financial gap in funding climate-compatible infrastructures in cities in developing countries (White &Wahba 2019). For instance, Ahmed et al. (2020) recounted that the challenge of funding was the reason for the delay in the implementation of Pakistan’s national water policy in the Sindh province integrating climate-resilient models.
Lack of political will
A country with a weak political will struggles to ensure the effective delivery of innovative adaptation solutions to climate change, such as climate-change policies in infrastructure projects (Rice 2014). A change in political leadership can be a barrier to the integration of climate-smart policies in all sectors of the economy, including PPP projects, if a succeeding political government is not as climate-conscious as the previous government (McGee &Taplin 2009). Political ideologies influence the fight against climate risks. Whilst center-left politicians mostly favour climate-related policies, center-right-wing parties oppose climate change policies (Boulianne &Belland 2022). With such a deep political divide, it is difficult to foment a common political power to counter the climate crisis in an economy.
Poor legal environment
For climate-smart policies in PPP projects to be successful, according to Desai et al. (2016), they must be supported by a detailed legal framework managed by highly qualified professionals to maintain confidence and attract the participation of private investors and commercial lenders. However, according to Lee et al. (2021), a weak legal framework has become the bane of countries in the global south in their quest to implement to transition to climate-resilient PPPs. In the same vein, PPPs have long been related to questions of legality depending on the details and the geographical location of a project (Ferreira et al. 2022, Zhang &Maruyama 2001). According to a study, Babatunde et al. (2015) mentioned an unclear legal framework for resolving PPP disputes is a significant hurdle to the implementation of energy-efficient PPP initiatives in developing nations.
Inadequate technology development and transfer
Mahat et al. (2019) research in Nepal highlighted inadequate technology development and transfer as a climate-induced problem for the development of public projects pressuring the country to seek foreign technical aid and resources. Zhang andMaruyama (2001) argued, on the other hand, about the huge risks involved in engaging technology transfer within climate change negotiations. The risks include extra costs associated with sharing technologies, establishing joint ventures, and transferring intellectual property rights. Zhang (2011) and Zheng et al. (2021) found that the existing degree of technology transfer is insufficient for public-private partnerships (PPPs) in minimizing climate risks. Given the present climate change crisis, a new strategy for technology transfer and techniques such as artificial intelligence is required to deal with the current climate change concerns.
Ineffective climate risk management
According to Anwar et al. (2021), inconsistent holistic risk assessment and management is a key challenge to achieving optimal private climate financing support for PPP projects. Because of this inconsistency, international investors refrain from injecting capital into high-risk economies, which makes it difficult to get financing facilities for PPP implementations (Rodrigo et al. 2020). Moreover, most projects executed within the PPP arrangements do not have a fundamental risk criterion and controls necessary for a PPP project to succeed, especially on climate risk distribution and risk-sharing. Despite the many benefits of public-private partnerships (PPPs) in the creation of constructed infrastructure, significant obstacles may arise because of inadequate climate risk management (Hoeft et al. 2021).
Managerial costs
Since the inception of climate policies in PPP projects, countries and industry partners have made a lot of progress in putting into place measures to meet the targets on net-zero emission targets. However, the cost of implementing the climate-smart models in PPP projects has high transaction costs (Osei-Kyei et al. 2019). A similar argument is made for climate-resilient buildings, but the widespread management costs incurred in the procurement processes of the projects put a heavy financial burden on private financiers. Employing experts and training existing construction workers come with huge investments in climate-friendly projects (Röck et al. 2020).
Lifecycle wastes and lapses in embracing circular principles
Dolla andLaishram (2018) posited that the growing population in urban cities could not keep up with the sanitation needs of the population, contributing to the climate crisis, and this is making climate change worse quickly. This increased rate of urbanization, such as what is seen in Chinese urban centers according to Anwar et al. (2021), might hinder attaining SDG 11, which is sustainable cities and communities. Although fast urbanization is a driving force behind PPP arrangements, such uncontrolled urbanization creates significant obstacles such as uncontrolled developments, crime, waste management concerns, traffic congestion, and restricted access to funding (Desai et al. 2016, Jayasena et al. 2020). Harman et al. (2015) recounted this challenge as part of a larger global problem in which local and national governments around the world are struggling to meet the basic needs of communities through the provision of circular urban infrastructure that limits waste and recycles the use of materials under the pressures from rapid urbanization and population growth.
Insufficient stakeholder participation/involvement
Lövbrand andStripple (2012) asserted that, in the development of sustainable livelihoods and infrastructure development, assessment should be done from a multi-stakeholder perspective of technical, stakeholder, and political perspectives. As a result, to effectively implement climate change policies, it is necessary to overcome the challenges of acquiring information from developing partnerships and all key stakeholders (Bisaro &Hinkel 2018). The involvement of all private financiers and municipal stakeholders, including governmental institutions, private businesses, and people, in the process of resilience building, boosts the success of the PPP project implementation is currently inadequate (Maraña et al. 2020). Collaborative partnerships that bring diverse stakeholders with a variety of multi-disciplinary backgrounds to coordinate policies at the state and national levels to raise awareness, build capacity, and promote change in the context of urban climate adaptation responses have yet to be fully realized in emerging markets (Liu et al. 2022).
Scarcity of climate-smart resources
The development and usage of limited low-carbon construction materials resources necessitate the challenges that current projects are facing to transition to circular zero-carbon construction products. The necessary partnerships, funding, and support to achieve set goals of sustainable infrastructure using the lowest carbon footprint with the propensity to be recycled and used in the future in PPP projects are lacking (Tian et al. 2022, Zhang et al. 2018).
Sustainability and maintenance of PPP infrastructure
The public sector's inability to maintain and operate sustainable infrastructure after the concession period of the PPP arrangement is a major setback in tackling climate risks in PPP projects (Jayasena et al., 2020: Desai et al., 2016).
Information and awareness gap
Bauer et al. (2012) mentioned that information is essential in addressing the climate crisis. It is also the vehicle via which public awareness and acceptance are raised (Saha 2018). Therefore, a knowledge gap on climate-smart policies relating to inadequate education and in-depth research makes it impossible to draw a comprehensive roadmap to manage climate change. Climate-resilient PPP implementation is hindered by a lack of information and knowledge in the sector, as evidenced by inadequate data on urban climate performance and technologies usage and monitoring lapses in achieving a sustainable built environment (Pinilla-De La Cruz et al. 2022). A scarcity of human capital both inside and between the public-private partnership infrastructure sector continues to undermine the ability to implement adaptation and mitigation solutions to climate change concerns (Ferreira et al. 2022).
4.4 Conceptual framework
The far-reaching impacts of extreme climate change are taking place everywhere, including developmental projects such as schools, hospitals, roads, and other physical infrastructures (Beery 2018). There is a significant variation in the consequences of the climate crisis from one geographical area to another. Harman et al. (2015) argued that not only do these changes take place in infrastructures, but they have extremely negative impacts on human lives and ecosystems and energy consumption. Further, the outcome of the extreme weather has impacts on private investment. Investors inject capital into a building or infrastructure to gain positive outcomes. Increasingly, it is becoming apparent that recouping private investment has become difficult due to low assurance in the resilience and sustainability of projects into the near future (Huang et al. 2018). These concerns together with the urgent need to protect the environment, are the main driving force behind climate action in the infrastructure sector.
Additionally, Fig. 5 demonstrates other driving forces for climate change policies in the infrastructure sector, including the pressure from environmentalists, state legislators and concerted efforts from world leaders to design and implement climate-smart policies that will crack down on excessive emissions from the PPP industry (Hoeft et al. 2021, Lövbrand &Stripple 2012). The relationships between the factors are influenced by the ongoing consultations and debates in the public discourse, the financial markets, and the infrastructure to act on climate change. The interplay between the vulnerability of infrastructures and the negative ramifications of carbon emissions kick start mental health and climate crisis (Gislason et al. 2021). The essence of analyzing the factors is to ensure that policy frameworks at the national and project levels take into consideration climate crisis.
The next key construct is climate change policies. Three key pillars of climate action include the mitigation, adaptation, and resilience of climate change. Adaption strategies of climate change in the built environment undergo the formulation of in-depth practices that embrace the weather conditions and the preservation of the environment in relation to infrastructures (Dhar &Khirfan 2017). Mitigation strategies aim at addressing the current fallouts of the climate crisis in terms of human and non-human effects (Schweizer et al. 2013). The resilience strategies aim at building infrastructures to respond to future occurrences of climate risks (Choi et al. 2021). This is crucial in reducing the impacts of climate change within the context of Goal 13 of the United Nations’ SDGs.
Finally, the third construct of the framework is the barriers to implementing climate-smart solutions. Addressing vulnerabilities of infrastructures is hampered by low interest and little to no strategies from project managers to improve upon construction practices that meet net zero emission targets. Although some countries have developed a clear document for climate action, it is still an illusion in the construction industry in many other nations with few practical policies to tackle the climate crisis by 2030, especially in the emerging economies (Kaminsky 2022). Moreover, the commitment to climate action remains a contentious issue, with political and religious fights, with the reduction of carbon emissions still being a hot-contested national debate (Juhola 2013). Climate change policies are also not clear in the infrastructure sector and most of the policies formulated are imaginary with almost no realistic conformation to the local climatic conditions (Bisaro &Hinkel 2018). A policy may be tailored to serve a country, but it may be less beneficial in another country.
The framework provides a platform for researchers, policymakers, and practitioners to delve into these matters and implement policies to manage them. The conceptual framework demonstrates the relationships between the key outcomes of the research and supports the providers' directions in resolving the climate crisis in the infrastructure sector. Although the conceptual framework is a theoretical model, it aims at assisting the formulation and management of climate change in PPP projects. This framework is not a legal rule book but a guide that illustrates the potential barriers that stakeholders must overcome to address the climate crisis in the PPP industry.
4.5 Gaps in literature and future directions
Abysmal action in the PPP industry to tackle climate change
While governments, societies, and businesses are still recovering from the shock of Covid-19, climate change appears as another global challenge that requires immediate action (Ebi et al. 2021). Scientific projections and studies predict unstable weather conditions and a rise in natural disasters because of failed climate adaptation and mitigation strategies (Mori et al. 2021). However, the role of the PPP industry in achieving the climate targets of the UN SDGs and the 2021 Glasgow Climate has been abysmal, with no clear roadmap among the key stakeholders in the industry (Fell &Mattsson 2021). Moreover, the collaborations between the private sector and the state to end the climate debacles in infrastructure development remain less explored in the PPP research. A critical review of existing studies demonstrates little or no awareness in the media about climate change in developing economies. The media landscape does not discuss the science of climate change and its impacts on many emerging economies. Further, the media is unable to publish and publicize relevant climate information to create awareness among people, particularly those in the PPP industry (Scott 2021). Several national factors influence how the media frames climate change coverage, but none of them depicts it as an immediate crisis requiring national policy in developing nations to address it (Günay et al. 2021). Therefore, immediate action coupled with widespread education on climate change will be beneficial in attaining the climate targets in the PPP industry.
Data challenges
Addressing the issues of climate change requires a strong and broad-based database relating to the various agreements and the actual fallouts of the climate crisis (Bodansky 2021). After many years of climate change treaties and meetings (Paris meeting, COPs), there is still no consensus-built database of climate change in the infrastructure sector. Dwivedi et al. (2022)d rensen et al. (2021) recounted the difficulty in gathering data on climate change of infrastructure projects for scientific research with problems ranging from logistical, financial, and political to ethical challenges. Furthermore, data on climate change plans, negotiation charts, financing of the agenda, and innovation remain a challenge due to different climatic conditions in areas where the PPP projects are constructed (Anwar et al. 2021). The varying climatic conditions make it difficult to tackle the issue of climate since the data for an area may not be applicable to another construction site. It is very pertinent that project managers and researchers establish foundational pillars in building a dataset that can serve all PPP projects taking into consideration external factors of a geographical area. Done rightly, this will reshape policies, management of climate, and its impact on infrastructure development around the world.
Investment into low-energy (net-zero)/ climate-resilient PPP infrastructure
Though infrastructure development undoubtedly leads to economic growth and advancement in diverse spheres, it has been noted to be a major contributor to carbon emissions through industrial and construction activities (Yuan et al. 2022). This demands the production of low carbon infrastructure, which generates fewer carbon emissions and promotes resilience against the climate. In recent years, there has been a surge in low carbon infrastructure investment in the energy sector from governments and private investors, with less focus on low carbon transport and buildings (Kennedy et al. 2014). Low-carbon infrastructure is taking place, but the momentum needs to step up with more private investments. The increasing population and rapid urbanization necessitate the creation of more climate-resilient infrastructure to support economic growth and development. In addition, emissions from transportation and buildings are more widespread and have negatively impacted the climate over the years (Creutzig et al. 2015). These infrastructures account for around 70% of worldwide greenhouse gas emissions (Meltzer 2016). Thus, there is a need for action to solve this problem. By 2030, the world will have spent $94 trillion on new infrastructure. This demands private investment to support the government spending to accomplish this goal in infrastructural development. Sustainable infrastructure investment can be beneficial for both economic growth and climate. The use of renewable energy (solar, wind) and sustainable building materials (hemp, reclaimed wood, precast concrete slabs) can eventually reduce environmental pollution and its resultant toll on humans and their cities (Fell &Mattsson 2021).
Artificial intelligence and machine learning
Achieving set net-zero targets requires countries and companies to quantify, monitor, and reduce emissions and, in most cases, offset carbon emissions generated. This can be made easy with the adoption and use of advanced technologies to speed up the carbon management process. Artificial intelligence and machine learning (AI/ML) come in handy to enhance the climate risk management of infrastructure projects. Many aspects of urban living and planning can benefit from AI/ML interventions (Wang et al. 2021a, Wang et al. 2021b). However, little research and models have been developed in relation to AI/ML in the PPP industry to countermeasure climate change. Thus, we encourage the adoption of AI/ML that has a capacity to carbon capture, cement green construction materials, and predict floating solar and tidal energy with the potential to reduce carbon emissions with the increased use of renewable energy and low CO2 production mechanisms (Cioffi et al. 2020). Future studies must lead the way in developing AI/ML-inspired climate models for PPP infrastructural projects.