Functionalizing building envelopes for greening and solar energy: Between theory and the practice in Egypt

The building sector is one of the most resource-intensive industries. In Egypt, buildings consume 60% of electricity, produce 8% of CO2 emissions, and anthropize agricultural land, peri-urban and urban landscapes. To compensate for these consumption patterns, building envelopes can become productive in terms of greening and energy production. This encompasses the implementation of productive building systems that include (a) greening systems such as building-integrated vegetation and agriculture systems and (b) solar energy systems such as building-applied and integrated photovoltaics. For Egypt, the transformation toward more productive buildings still lacks a holistic understanding of their status and implementation requirements. This paper undergoes a comprehensive analysis of the two systems’ classifications, benefits, challenges, and implementation aspects based on a thorough assessment of 121 studies and 20 reports addressing them. This is coupled with a contextual analysis using questionnaires (n = 35) and semi-structured interviews (n = 13) with Egyptian experts and suppliers. Results showed that a large variety of systems is studied in literature and exists in the local market. Among the most purchased productive building systems in the Egyptian market, according to experts, are hydroponics (selected by 75% of respondents), planter boxes/pots (50%), roof-mounted photovoltaic panels (95%), and solar water heaters (55%). The main benefits of greening and solar energy systems are identified as enjoying the greenery view (95%) and reducing energy expenses (100%), respectively. The high initial cost was considered the main barrier for both systems. Multiple commonalities between the two systems in terms of spatial and environmental applicability aspects (e.g., accessibility and safety, net useable area, sun exposure, wind exposure) and environmental performance aspects (e.g., energy demand and emissions reduction, heat flow reduction) were identified. Lastly, we highlight the importance of analyzing integrated solutions that make use of the identified synergies between the systems and maximize the production potentials

Applicability of PV rooftops versus agriculture rooftops in the residential buildings of Nasr city, Cairo

Urban rooftops in the Egyptian built environment are a clear example of a massively wasted re-source. They can contribute to energy and food production as well as increase the return on in-vestment in the real estate sector by implementing Agri and PV rooftop systems. The paper aims at tapping into the unexplored case of multi-unit residential buildings of Cairo to assess the Agri and PV systems’ applicability on their rooftops. For this purpose, it conducts a spatial analysis for one of the Cairene middle-income districts; Nasr city. Overlaying multiple layers of applicability aspects derives a conclusion about the percentage of applicable rooftops for Agri versus PV systems in the district’s different blocks typologies

Functionalizing building envelopes for greening and solar energy : between theory and the practice in Egypt

The building sector is one of the most resource-intensive industries. In Egypt, buildings consume 60% of electricity, produce 8% of CO2 emissions, and anthropize agricultural land, peri-urban and urban landscapes. To compensate for these consumption patterns, building envelopes can become productive in terms of greening and energy production. This encompasses the implementation of productive building systems that include (a) greening systems such as building-integrated vegetation and agriculture systems and (b) solar energy systems such as building-applied and integrated photovoltaics. For Egypt, the transformation toward more productive buildings still lacks a holistic understanding of their status and implementation requirements. This paper undergoes a comprehensive analysis of the two systems’ classifications, benefits, challenges, and implementation aspects based on a thorough assessment of 121 studies and 20 reports addressing them. This is coupled with a contextual analysis using questionnaires (n = 35) and semi-structured interviews (n = 13) with Egyptian experts and suppliers. Results showed that a large variety of systems is studied in literature and exists in the local market. Among the most purchased productive building systems in the Egyptian market, according to experts, are hydroponics (selected by 75% of respondents), planter boxes/pots (50%), roof-mounted photovoltaic panels (95%), and solar water heaters (55%). The main benefits of greening and solar energy systems are identified as enjoying the greenery view (95%) and reducing energy expenses (100%), respectively. The high initial cost was considered the main barrier for both systems. Multiple commonalities between the two systems in terms of spatial and environmental applicability aspects (e.g., accessibility and safety, net useable area, sun exposure, wind exposure) and environmental performance aspects (e.g., energy demand and emissions reduction, heat flow reduction) were identified. Lastly, we highlight the importance of analyzing integrated solutions that make use of the identified synergies between the systems and maximize the production potentials

Global, regional, and national prevalence of adult overweight and obesity, 1990–2021, with forecasts to 2050: a forecasting study for the Global Burden of Disease Study 2021

Background: Overweight and obesity is a global epidemic. Forecasting future trajectories of the epidemic is crucial for providing an evidence base for policy change. In this study, we examine the historical trends of the global, regional, and national prevalence of adult overweight and obesity from 1990 to 2021 and forecast the future trajectories to 2050. Methods: Leveraging established methodology from the Global Burden of Diseases, Injuries, and Risk Factors Study, we estimated the prevalence of overweight and obesity among individuals aged 25 years and older by age and sex for 204 countries and territories from 1990 to 2050. Retrospective and current prevalence trends were derived based on both self-reported and measured anthropometric data extracted from 1350 unique sources, which include survey microdata and reports, as well as published literature. Specific adjustment was applied to correct for self-report bias. Spatiotemporal Gaussian process regression models were used to synthesise data, leveraging both spatial and temporal correlation in epidemiological trends, to optimise the comparability of results across time and geographies. To generate forecast estimates, we used forecasts of the Socio-demographic Index and temporal correlation patterns presented as annualised rate of change to inform future trajectories. We considered a reference scenario assuming the continuation of historical trends. Findings: Rates of overweight and obesity increased at the global and regional levels, and in all nations, between 1990 and 2021. In 2021, an estimated 1·00 billion (95% uncertainty interval [UI] 0·989–1·01) adult males and 1·11 billion (1·10–1·12) adult females had overweight and obesity. China had the largest population of adults with overweight and obesity (402 million [397–407] individuals), followed by India (180 million [167–194]) and the USA (172 million [169–174]). The highest age-standardised prevalence of overweight and obesity was observed in countries in Oceania and north Africa and the Middle East, with many of these countries reporting prevalence of more than 80% in adults. Compared with 1990, the global prevalence of obesity had increased by 155·1% (149·8–160·3) in males and 104·9% (95% UI 100·9–108·8) in females. The most rapid rise in obesity prevalence was observed in the north Africa and the Middle East super-region, where age-standardised prevalence rates in males more than tripled and in females more than doubled. Assuming the continuation of historical trends, by 2050, we forecast that the total number of adults living with overweight and obesity will reach 3·80 billion (95% UI 3·39–4·04), over half of the likely global adult population at that time. While China, India, and the USA will continue to constitute a large proportion of the global population with overweight and obesity, the number in the sub-Saharan Africa super-region is forecasted to increase by 254·8% (234·4–269·5). In Nigeria specifically, the number of adults with overweight and obesity is forecasted to rise to 141 million (121–162) by 2050, making it the country with the fourth-largest population with overweight and obesity. Interpretation: No country to date has successfully curbed the rising rates of adult overweight and obesity. Without immediate and effective intervention, overweight and obesity will continue to increase globally. Particularly in Asia and Africa, driven by growing populations, the number of individuals with overweight and obesity is forecast to rise substantially. These regions will face a considerable increase in obesity-related disease burden. Merely acknowledging obesity as a global health issue would be negligent on the part of global health and public health practitioners; more aggressive and targeted measures are required to address this crisis, as obesity is one of the foremost avertible risks to health now and in the future and poses an unparalleled threat of premature disease and death at local, national, and global levels. Funding: Bill & Melinda Gates Foundation

Productive Building Systems in the residential sector in Egypt : an investigation into the implementation potential of greening and solar energy systems in new cities

Globally, human actions are driving irreversible environmental phenomena including climate change and global warming. The rapid expansion of urban areas and the resource-intensive building sectors have amplified the implications of these phenomena on urban populations at global and local levels. Therefore, a transformation was spurred towards the regenerative paradigm to offset the adverse impacts of current building practices and increase the positive impact of buildings on the natural environment. In line with the regenerative approach, this research focuses on Productive Building Systems (PBSs) - particularly greening and solar energy systems. PBSs could transform building envelopes into productive structures that grow vegetation, produce food, harvest solar energy, and compensate, even in part, for land and habitat replaced by buildings. In Egypt, despite the high productivity potential of PBSs, their implementation rates are lower than expected. To bridge this gap, the dissertation aims at conducting a multi-faceted investigation of the implementation potential of PBSs in the understudied context of new residential buildings in Egypt. Influenced by implementation science theories, three priority facets - technical, social, and behavioral - were investigated using a mixed-method approach to address several gaps in theory and practice. The findings were discussed under three corresponding topics (a) literature review and technical frameworks covering PBS types and implementation requirements, (b) social acceptance and implementation preferences among potential consumers, and (c) behavioral and socio-psychological factors influencing social acceptance. In the end, the dissertation provided a comprehensive understanding of the dynamics of two main PBSs - greening and solar energy systems - in comparison, under the prevailing conditions in Egypt. It tailored concrete recommendations to support involved stakeholders in promoting PBSs implementation in Egypt and countries of comparable climatic and socio-economic conditions, to ultimately create more productive, livable, and resource-efficient built environments

Towards sustainable urbanization in new cities : social acceptance and preferences of agricultural and solar energy systems

Social acceptance of end users is indispensable for the implementation of agricultural and solar energy systems to create a more sustainable and productive residential building sector. Thus, the main aim of this study is to investigate the social acceptance level of the two systems and the implementation preferences of Egyptian end users, i.e., residents, in relation to their different sociocultural backgrounds. Given that most of the construction in Egypt is taking place in new cities, the acceptance of such systems strongly relates to societal implications for urban sustainability. An online survey was therefore disseminated to the residents of new cities in the Greater Cairo Region in Egypt (n = 274). A contingency analysis was conducted using the SPSS tool, calculating the Chisquared and Fisher tests to identify significant associations between the variables. Results indicated a high level of social acceptance of both the agricultural (71 %) and solar energy (64 %) systems. The attitude of residents towards the systems and their experience using them were the variables exhibiting the highest association with social acceptance of agricultural systems (p < 0.001 for attitude and experience) and solar energy systems (p = 0.04 for attitude and p = 0.002 for experience). The most preferred system types were the horizontal planters on hand railings and roof-mounted photovoltaics. Responses showed that production was the main aim for agricultural systems, while economic returns were the main aim for solar systems. However, both systems faced the same barriers, especially in relation to economic barriers. Out of the 12 sociocultural variables tested, respondents’ age had the most significant impact on the implementation preferences of both systems followed by gender, residence type, and access to shared facilities. Our study addressed a knowledge gap by comparing the two systems to identify the common or different reasons behind the disparity between their high theoretical potential versus low on-ground implementation. Future research could investigate other underlying factors behind social acceptance beyond the analyzed sociocultural aspects and tackle the types of each system in detail

Factors affecting the social acceptance of agricultural and solar energy systems : the case of new cities in Egypt

Can the building sector become productive and, in parallel, help create livable spaces? Agricultural and solar energy systems can contribute to the building sector’s transformation; however, research on these systems has mostly focused on technological development and achieved gains, while overlooking a key driver of success, which is social acceptance. Only recently has the discussion on social acceptance of the systems gained momentum revealing that their adoption, especially in residential sectors, is bound to end users. Therefore, using a quantitative, survey-based, case study approach, we investigated what influences the social acceptance of end users, i.e., the residents of residential buildings in Egyptian new cities. Based on UTAUT - a Technology Acceptance theory - seven underlying factors were tackled using a statistical contingency analysis (SPSS, n = 274) to test their association with (a) social acceptance of agricultural and solar energy systems and (b) the sociocultural background of the residents. Results revealed that social acceptance of the systems was associated with factors like the expected effort for implementation, concerns and anxieties about the systems, external supporting conditions, and social influences – while surprisingly, it was not associated with the expected performance of the systems, their perceived costs, and the need for financial support. Most studied factors showed associations with the sociocultural aspects, except for the expected effort and perceived cost of solar systems and financial facilitations of both systems, which proved to be completely independent of the sociocultural background of the residents. The conducted analysis and concluded insights about the underlying factors behind social acceptance have not been previously covered in detail for the two systems in comparison, especially for the case of new Egyptian residences. The study findings can support relevant stakeholders such as policymakers, suppliers, engineers, etc. in triggering the social acceptance of the systems in Egypt and contexts of similar settings

Factors affecting the social acceptance of agricultural and solar energy systems: The case of new cities in Egypt

Can the building sector become productive and, in parallel, help create livable spaces? Agricultural and solar energy systems can contribute to the building sector’s transformation; however, research on these systems has mostly focused on technological development and achieved gains, while overlooking a key driver of success, which is social acceptance. Only recently has the discussion on social acceptance of the systems gained momentum revealing that their adoption, especially in residential sectors, is bound to end users. Therefore, using a quantitative, survey-based, case study approach, we investigated what influences the social acceptance of end users, i.e., the residents of residential buildings in Egyptian new cities. Based on UTAUT – a Technology Acceptance theory – seven underlying factors were tackled using a statistical contingency analysis (SPSS, n = 274) to test their association with (a) social acceptance of agricultural and solar energy systems and (b) the sociocultural background of the residents. Results revealed that social acceptance of the systems was associated with factors like the expected effort for implementation, concerns and anxieties about the systems, external supporting conditions, and social influences – while surprisingly, it was not associated with the expected performance of the systems, their perceived costs, and the need for financial support. Most studied factors showed associations with the sociocultural aspects, except for the expected effort and perceived cost of solar systems and financial facilitations of both systems, which proved to be completely independent of the sociocultural background of the residents. The conducted analysis and concluded insights about the underlying factors behind social acceptance have not been previously covered in detail for the two systems in comparison, especially for the case of new Egyptian residences. The study findings can support relevant stakeholders such as policymakers, suppliers, engineers, etc. in triggering the social acceptance of the systems in Egypt and contexts of similar settings

Perceptions of building-integrated nature-based solutions by suppliers versus consumers in Egypt

Can Building-Integrated Nature-based Solutions (BI-NbS) reach their full potential in the Global South? In the Egyptian context, BI-NbS are relatively new with an identified gap between the high potential in theory and low implementation rates in practice. To bridge this gap, the study conducts an in-depth investigation of BI-NbS market conditions to reveal the current trends in the residential buildings market in Egypt. It also identifies the gaps and overlaps in the perceptions of the suppliers and consumers of BI-NbS. Results reveal that the residential sector sales mainly target high-income groups yet very limited and dominated by rooftop systems. Suppliers advocate for high-tech systems over low-tech systems, whereas consumers prefer the latter. The perceptions of suppliers and consumers mostly align regarding the basic aspects such as the production and operation preferences as well as the anxieties and concerns about the relatively new BI-NbS in this regional context. However, they diverge in key aspects affecting market penetration such as implementation conditions, aims, and barriers. Accordingly, the study identified the gap between suppliers and consumers, and outlined recommendations, directed to suppliers and policymakers, for improved market development and local implementation of BI-NbS in emerging markets of the Global South, such as Egypt