Passive design considers local climate conditions, building orientation, form, massing, and materials to minimize the need for mechanical and electrical systems. In hot climates, this involves providing solar shading, natural ventilation opportunities and passive cooling through thermal mass and evaporative cooling, where appropriate. Passive design, including nature-based solutions, plays a crucial role in sustainable cooling for cities and buildings, regardless of whether air-conditioning is utilized.

A simulated demonstration project highlighted how cost-effective measures such as window film and shading can reduce cooling energy demand by 20 percent compared to typical design and construction methods. With the addition of an insulated building shell, the cooling demand reduction reaches 44 percent.

The new building code mandates passive design requirements for residential and office buildings, including a maximum window-to-wall ratio of 20 percent or adequate solar shading and roof insulation with a thermal resistance of at least 1.25 m2K/W (this measures the resistence to heat flow known as the R-value). 

In terms of efficiency, the code stipulates that all air-conditioning units must have a minimum Energy Efficiency Ratio (EER) of 2.8 (this is the ratio of output cooling energy to input electrical energy, i.e. a EER of 2.8 means 1kWh of electricity will provide 2.8kWh of cooling energy). This requirement is further supported by the government and the UNEP project "Scaling Up Energy-Efficient and Climate-Friendly Cooling in Nigeria’s Nationally Determined Contributions Revision", which established a National Technical Committee in March 2023. [3]

In addition to formal building sectors, paying special attention to informal settlements and socially vulnerable communities is crucial, which often experience higher heat exposure due to dense housing, heat-trapping construction materials, and limited vegetation. One study showed that 70 percent of occupants in low-income housing in Abuja experience thermal discomfort. [4] Nature-based and passive design solutions can be implemented to lower internal temperatures in low-income housing, mitigating thermal discomfort and preventing the negative health effects of heat stress. For instance: 

• In Lagos, vegetation on external walls (green walls) reduced indoor temperatures by an average of 2.3°C, achieving 90-100 percent internal comfort conditions. [5] 
• Shading devices, like verandas, can reduce the frequency of indoor thermal discomfort by 8.5-19.5 percent according to validated simulations. [6]

Effective implementation is crucial for the success of any energy-efficiency building code or sustainable cooling solution. In Nigeria, raising awareness and fostering collaboration among all stakeholders in the building industry is essential for implementing its Building Energy Efficiency Code [7]. Moreover, implementing passive design measures in low-income urban environments requires a comprehensive approach, including community participation, capacity building and ongoing monitoring and evaluation. 

Notes and references

[1] The Critical 9 countries are: Bangladesh, Brazil, China, India, Indonesia, Mozambique, Nigeria, Pakistan and Sudan.
[2] Geissler, Susanne & Österreicher, Doris & Macharm, Ene. (2018). Transition towards Energy Efficiency: Developing the Nigerian Building Energy Efficiency Code. Sustainability. 10. 2620. 10.3390/su10082620.
[3] https://united4efficiency.org/inauguration-of-national-technical-committee-drives-progress-towards-energy-efficient-and-climate-friendly-cooling-in-nigeria/
[4] Michael U. Adaji, Timothy O. Adekunle, Richard Watkins, Gerald Adler, Indoor comfort and adaptation in low-income and middle-income residential buildings in a Nigerian city during a dry season, Building and Environment, Volume 162,2019,106276,ISSN 0360-1323, https://doi.org/10.1016/j.buildenv.2019.106276.
[5] Akinwolemiwa, O.H.; de Souza, C.B.; De Luca, L.M.; Gwilliam, J. Building community-driven vertical greening systems for people living on less than £ 1 a day: A case study in Nigeria. Build. Environ. 2018, 131, 277–287
[6] Abdulkareem, M.; Al-Maiyah, S.A.M. Environmental Performance of Abuja’s Low-Income Housing: Understanding the Current State to Inform Future Refinement. In Proceedings of the PLEA (Passive Low Energy Architecture) Conference, Hong Kong, 10–12 December 2018.
[7] Ochedi, Ekele & Taki, Professor. (2019). Towards Energy Efficient Buildings in Nigeria: Challenges and Opportunities. JOURNAL OF ENGINEERING AND ARCHITECTURE. 7. 10.15640/jea.v7n2a14.
 

Applied in agricultural cold chains, CaaS enables access to cooling for small- and medium-scale farms, increasing the quality and value of food, and reducing waste. Every year, farmers in India incur nearly USD 12,520 million in post-harvest losses due to inadequate storage facilities and a lack of energy infrastructure. 25 to 35 percent of cultivated food is wasted due to a lack of proper refrigeration and other supply chain bottlenecks, and only 6 percent of the food produced in India currently moves through the cold chain. To make matters worse, information asymmetry and the lack of quality consciousness, crucial for setting the price of crops, lower farmers’ ability to monetize on their produce and earn proportionately to their original investment. Many other countries face similar problems.

To address these problems, BASE and the Swiss Federal Laboratories for Materials Sciences and Technology (Empa) came together under the data.org global innovation challenge to launch the Your Virtual Cold Chain Assistant (Your VCCA) initiative in India, which was later expanded to Nigeria with the support of the German Federal Ministry for Economic Cooperation and Development (BMZ) and the Deutsche Gesellschaft für Internationale Zusammenarbeit (GIZ). Your VCCA enables smallholder farmers to access cold storage by paying per crate per day and to leverage market intelligence via an open-access, data-driven mobile application.

Cold storage providers in India and Nigeria are adopting the app to digitize key processes, such as introducing a digital inventory, which can help operationalize CaaS. Through these processes, the app provides users with post-harvest expertise to predict the shelf life of produce in storage rooms, equipping farmers with the information and technical support required to secure the best possible price for their produce.

Partners in India include Coolcrop, Oorja and Koel Fresh, while in Nigeria the project’s first partner is ColdHubs. In order to support the effective rollout of CaaS in the agricultural sector, BASE and Empa have also designed a multi-layer interactive web map by collating and visualizing different raster and vector data layers related to India’s fresh produce supply chain to help stakeholders understand the potential for sustainable cooling solutions across the country. This is an example of how innovative business models can be combined with leveraging data-driven techniques to transform the agriculture sector and strengthen agri-food systems and supply chains. 

By gaining access to cooling facilities and market intelligence, it is possible to improve food security, increase smallholders’ income, and reduce food loss, while mitigating the impact of cooling on the environment. Currently, CaaS is being implemented in India and in Nigeria, benefitting over 500 farmers. It is already gaining significant traction and since it will be made available through open source, its adoption can be scaled up well beyond the pilot regions and countries. The innovative components of the mobile app can also be integrated into existing digital solutions to facilitate its adoption and secure a wider impact.

A large rollout of CaaS by 2025 would translate into its widescale adoption in the agricultural supply chain and improved access to market intelligence to those who need it most, reducing food loss and increasing smallholder income around the world while limiting the impact of agriculture and cold storage on the climate through the use of sustainable technology.

Meet our Global Panel on Access to Cooling member from BASE

Measuring the impact of health facility electrification

Electricity is generally understood as a prerequisite to almost all aspects of a well-functioning health facility, but it is often difficult to measure or quantify the direct impact of electricity on health outcomes due to its many determinants and contextual factors. Therefore, impact is often measured indirectly through the lens of a specific aspect of health services, which can include service delivery, preventative care, vaccine storage and delivery, maternal health, and health-seeking behaviour. These pathways are examined in SEforALL’s recently launched Powering Healthcare Impact Factsheet, which compiles existing, published studies on the linkages between reliable power at health facilities and improved health outcomes.

While there are still several gaps in better understanding and specifically in quantifying the impact of reliable energy on health outcomes, the available research supports the importance of reliable power in the health sector. For example, a study in India found that primary healthcare centres without access to electricity had 64 percent less deliveries, 39 percent less in-patients, and 38 percent less out-patients. [1] Another study in Zambia found the acquisition of solar-powered microscopes led to a 25–30 percent increase in the number of people tested for tuberculosis (TB), contributing towards the increase in the TB cure rate from 62 percent  to 72 percent  in the area. [2]

Women are also disproportionately affected by low levels of electricity access, with a study in Uganda revealing that electricity had the second highest protective effect on maternity health after availability of midwives, reducing the case fatality rate by 61 percent. [3] While these data points provide a general understanding of the importance of reliable energy in a health facility setting, additional investment in impact data can allow the sector to better understand and quantify the impact that reliable power can have on health service delivery and health outcomes. 

Taking stock of global efforts

To gain a better understanding of global progress and identify potential opportunities for coordination, SEforALL circulated a sector-wide survey to document past (2015-2020), ongoing, and future health facility electrification interventions. Analysis of the resulting dataset, which includes more than 270 interventions by 81 organizations across 56 countries, showed an increase in the number of interventions, from 118 completed to 152 in the pipeline. Furthermore, the scale of interventions was larger, from 5,590 facilities targeted in completed interventions to 15,868 facilities targeted in ongoing/planned interventions. [4]

The survey also found that ongoing and planned interventions significantly favour the deployment of larger systems (above 1kWp), showing that increasingly organizations are including facility-wide energy needs in their project design. This trend could also be attributed to the significant decline in solar PV system costs in the past decade (by 82 percent between 2010 and 2019), [5] allowing implementation agencies to deploy larger solutions that can power more loads. 

Figure 1: Heatmap of completed and ongoing health facility electrification interventions

Country-level market assessments

To complement efforts to measure global progress of health facility electrification, country-level assessments present a key opportunity to analyze the energy access gap in the health sector in a more granular way, as well as identify the most appropriate technological and financial solutions to electrify health facilities at a national level. SEforALL and several other organizations are currently developing these types of country-level assessments, which can provide an important stepping stone towards project development. For example, SEforALL recently published the Powering Healthcare Market Assessment and Roadmap for Nigeria, which it developed with support from Power Africa and in close coordination with the Rural Electrification Agency and the National Primary Health Care Development Agency. This country-level assessment aims to provide the Government of Nigeria and its development partners with a data-driven overview and practical recommendations for planning and coordination of electrifying the country’s underserved health facilities. The analysis estimates that there remains an energy access gap in the public health sector of approximately 30 to 40 percent, primarily in primary health care facilities. The document also highlights a USD 525 million investment need to equip 10,000 primary healthcare centres with reliable and renewable power and keep them operational for 15 years.  

Building a global, multilateral, intersectoral platform

To overcome implementation barriers and achieve the goal of universal electrification of health facilities, stronger global ambition and increased coordination is needed. To address this, SEforALL and Power Africa led a coalition of organizations from both the energy and health sectors around a Multilateral Energy Compact for Health Facility Electrification, which was launched during the High-level Dialogue on Energy in September 2021. To raise global ambition, the Energy Compact has set a global, sectoral target of electrifying 25,000 health facilities with clean and reliable power solutions by 2025. The compact also targets challenges in data, coordination, and implementation models by setting ambitions to invest in better data. The Energy Compact also complements the Strategic Roadmap on Health and Energy under the Health and Energy Platform for Action (HEPA), a platform hosted by the World Health Organization (WHO) for energy and health stakeholders to coordinate their efforts to achieve Sustainable Development Goal 3 (SDG3) and SDG7 in parallel.

As the data and interventions referenced above show, the energy access gap is still significant, and progress is slow. Significant barriers remain, most notably on data availability, long-term sustainable delivery models, and innovative financing. However, the last few years have seen a significant upshift in both momentum and interest to address the issue of energy poverty in the health sector. To achieve the goal of universal electrification of health facilities by 2030, maintaining this momentum and strengthening intersectoral coordination will be crucial.

Notes and references

[1] https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0252705 
[2] https://www.tandfonline.com/doi/abs/10.1080/09709274.2008.11906112 
[3] https://obgyn.onlinelibrary.wiley.com/doi/full/10.1016/j.ijgo.2007.05.019 
[4] As of 20 April  2022. For updated numbers, please visit the Powering Healthcare Intervention Heatmap
[5] https://www.irena.org/publications/2020/Jun/Renewable-Power-Costs-in-2019

How to use the interactive map

Source: Climate Change Knowledge Portal, The World Bank Group, 2022

Between 2015 and 2019, Dhaka added 0.93 square kilometers of built-up area for domestic and commercial use. This buildup came at the expense of 0.27 square kilometers of herbaceous vegetation, 0.44 square kilometers of cultivated and managed vegetation, and 0.1 square kilometers of herbaceous wetland.

Dhaka is expected to experience sustained high temperatures above 25°C in the most optimistic scenario, and a significant number of dangerous heat days over 35°C between March and June annually. The loss of cultivated land for fruits and vegetables not only implies a reduced ability to grow crops locally, but also diminishes the resilience of a growing urban population to the dangers of extreme heat. Understanding this impact and placing emphasis on urban greening and land to cultivate produce is likely to benefit both the UHIE in the city as well as food security. 

How to use the interactive map

Source: Climate Change Knowledge Portal, The World Bank Group, 2022

Between 2015 and 2019, Jakarta increased its built-up area by 0.87 square kilometers at the expense of 0.25 square kilometers of herbaceous vegetation, 0.19 square kilometers of cultivated and managed vegetation, and 0.1 square kilometers each of bare/sparse vegetation and water bodies. This process also included the removal of 0.14 square kilometers of open forest that would have had a passive cooling effect on urban areas. 

These changes were driven by increasing urbanization, but in combination with a growing number of days above 25°C annually, are likely to exacerbate the UHIE in the city. Even though Jakarta is not projected to have many days with dangerous heat (above 35°C), this trend will lead to increased cooling needs that could dramatically increase energy demand if met with inefficient, active cooling technologies.  An expansion of green urban areas through land-use planning would help reverse these losses and reduce heat stress felt by residents on high-temperature days.

How to use the interactive map

Source: Climate Change Knowledge Portal, The World Bank Group, 2022

Between 2015 and 2019, Karachi gained 6.63 square kilometers of built-up area at the expense of 1.82 square kilometers of shrubs, 0.18 square kilometers of herbaceous vegetation, 0.31 square kilometers of cultivated and managed vegetation, 3.6 square kilometers of bare or sparse vegetation, and 0.74 square kilometers of open forest.

Karachi made significant changes to its land-use patterns between 2015 and 2019, which has implications for food safety, agricultural production and thermal comfort. While the built-up area increased by 6.63 square kilometers, land used for cultivating produce grew by a significantly larger amount, 213 square kilometers. This provides the city with resources to grow local produce, benefitting residents and farmers through better food security and enhanced agricultural incomes, though there is a need for an expansion of the local cold chain to reduce potential post-harvest losses.

With Karachi set to experience a high number of days with dangerous heat between April and October every year, further urban planning efforts to reduce the UHIE and reliance on inefficient, mechanical cooling would especially benefit the most vulnerable urban dwellers.

How to use the interactive map

Source: Climate Change Knowledge Portal, The World Bank Group, 2022

Between 2015 and 2019, Lagos saw an increase of 0.43 square kilometers of built-up area. This came at the expense of 0.37 square kilometers of herbaceous vegetation, and marginal reductions in cultivated and managed vegetation, bare or sparse vegetation, water bodies and open forest.

Even in the most optimistic scenario, it is likely that there will be an increase in the number of days with dangerous heat (more than 35°C) per year for Lagos. Coupling this with rising sea levels, urbanization processes need to not only factor in human comfort and safety but also increased urban resilience.

How to use the interactive map

Source: Climate Change Knowledge Portal, The World Bank Group, 2022

Between 2015 and 2019, Maputo increased its built-up area by 0.3 square kilometers and lost 0.12 square kilometers of herbaceous vegetation, as well as marginal amounts of shrubs, cultivated and managed vegetation, water bodies and open forest. 
Mozambique does not have a large urban population — 63 percent of its people still live in rural areas —  [8] and this is reflected in the observed land-use changes. But the city is planning for expansion, including through the Maputo Urban Transformation Project. [9]

It is expected to see over four days of dangerous heat (+35°C) annually between September and February, presenting urban planners in Maputo with a unique opportunity to plan early for the increasing effects of heat, for example through natural heat sinks, increased green spaces and improved passive cooling measures. 
 

How to use the interactive map

Source: Climate Change Knowledge Portal, The World Bank Group, 2022

Between 2015 and 2019, Mumbai gained 0.9 square kilometers of built-up area at the expense of 0.14 square kilometers of herbaceous vegetation, 0.14 square kilometers of cultivated and managed vegetation, 0.28 square kilometers of closed forest, 0.16 square kilometers of open forest, and lesser amounts from shrubs, bare/sparse vegetation and water bodies.

Each year large segments of India’s population move to Mumbai from rural areas for social, economic and environmental opportunities. This migration has contributed to the expansion of informal settlements, including the Dharavi slum that is now home to more than 1 million people. [10] With projections for at least 15 days per month of dangerous heat between March and June each year, these people will be increasingly vulnerable to a lack of access to cooling.

Heat-action planning, and public cooling centres are among the types of low-cost solutions that can help meet their cooling needs. So too is urban greening, which was prioritized by the Government of Maharashtra in its recent climate change action plan. [11]

How to use the interactive map

Source: Climate Change Knowledge Portal, The World Bank Group, 2022

Between 2015 and 2019, Omdurman gained 0.48 square kilometers of built-up area at the expense of bare or sparse vegetation typical to the climate of the region.

The Omdurman-Khartoum region has grown rapidly over the past three decades and is projected to see over 20 days per month of dangerous heat between April and October annually between 2020 and 2039. In addition to heat, increased flooding over the past decade has also created challenges for urban residents. [12] With this in mind, the city has a unique opportunity to use urban planning and expansion processes to mitigate both urban heat and flooding risks at the same time, leveraging its water resources for nature-based urban cooling. 

How to use the interactive map

Source: Climate Change Knowledge Portal, The World Bank Group, 2022

Between 2015 and 2019, São Paulo, Brazil increased its built-up area by 2.27 square kilometers and reduced its area of herbaceous vegetation by 1.1 square kilometers and its area of open forest by 1.03 square kilometers. The city also saw small reductions in its areas of cultivated and managed vegetation, bare or sparse vegetation, herbaceous wetland and closed forest.

In São Paulo, rapid urbanization is increasing the number of people living in informal settlements known as favelas. These are typically constructed to a low standard, often by residents themselves, and are often located on wasteland, marshy land, or in flood-prone areas.

The city experiences sustained temperatures above 25°C in the summer months and is also projected to see four days per month of dangerous heat between September and November every year, exposing these residents to significant risks from lack of access to cooling. Targeted efforts to mitigate these risks include land-use planning changes that prioritize green spaces near favelas, and heat-action planning that provides them with public cooling centres on days when temperatures exceed 35°C.

How to use the interactive map

Source: Climate Change Knowledge Portal, The World Bank Group, 2022

Between 2015 and 2019, Shanghai increased its built-up area by 8.96 square kilometers with a decrease of 0.78 square kilometers of shrubs, 1.32 square kilometers of herbaceous vegetation, 3.48 square kilometers of cultivated and managed vegetation, 0.16 square kilometers of herbaceous wetland, 0.16 square kilometers of open forest with evergreen broad leaf, and 3.38 square kilometers of open forest.

Shanghai has observed the highest increase in its built-up area among the major cities in the Critical 9 countries. The increase contributes to increased demand for air-conditioning and refrigeration systems, highlighting the need for energy-efficient and climate-friendly technologies. Demand can be expected to be particularly high in July and August, where temperatures are projected to exceed 35°C for three days each month.  

For its most vulnerable residents, green spaces, passive cooling, and more vegetation can provide relief while reducing the UHIE and minimizing the energy necessary for cooling needs. 

Notes and references

[1] Global Land Cover, Copernicus. Land Cover Viewer (vito.be)
[2] Buchhorn, M. ; Lesiv, M. ; Tsendbazar, N. - E. ; Herold, M. ; Bertels, L. ; Smets, B. Copernicus Global Land Cover Layers — Collection 2. Remote Sensing 2020, 12, Volume 108, 1044. DOI 10.3390/rs12061044
[3] Q-GIS software was used, which is a free and open-source cross-platform GIS software application that supports viewing, editing, and analysis of geospatial data. Discover QGIS
[4] RStudio is an Integrated Development Environment (IDE) for R, a programming language for statistical computing and graphics. About RStudio - RStudio
[5] The U.N. Climate report’s five futures – decoded. Explainer: The U.N. climate report's five futures - decoded | Reuters
[6] Climate Change Knowledge Portal (CCKP). About us | Climate Change Knowledge Portal (worldbank.org)
[7] Ürge-Vorsatz, D., Petrichenko, K., Antal, M., Staniec, M., Labelle, M., Ozden, E., Labzina, E. Best-Practice Policies for Low Energy and Carbon Buildings. A Scenario Analysis. Research report prepared by the Center for Climate Change and Sustainable Policy (3CSEP) for the Global Buildings Performance Network. May 2012.
[8] Rural population – Mozambique, The World Bank, 2022. Link.
[9] Mozambique Receives $100 Million for its Maputo Urban Transformation Project, The World Bank, 2020. Link.
[10] Urbanization in contrasting cities, BBC, 2022. Link.
[11] The Hindu, 18 March 2022, Link.
[12] Andrea Zerboni et. al (2021) The Khartoum-Omdurman conurbation: a growing megacity at the confluence of the Blue and White Nile Rivers, Journal of Maps, 17:4, 227-240, DOI: 10.1080/17445647.2020.1758810