Harvesting Solutions Research Articles

Optimizing printed thermoelectric generators with geometry and processibility limitations

Fully printed thermoelectric generators (TEGs) are a promising solution for large scale energy harvesting and waste heat recovery in a broad range of applications. Due to large variations in heat transfer coefficients and temperatures, it is necessary to include these properties of the specific heat source in the design process of the TEGs. Oftentimes, this leads to additional, geometric requirements for the devices. The limited layer thickness of the printing process imposes further limitations on the device geometry. Here, we present an analytical method to design and optimize fully printed TEGs manufactured by a screen-printing technique and considering its geometric design limitations. The design process includes choosing between a planarly printed device architecture and a folded device architecture. Furthermore, the limited device thickness and the presence of a filler material in printed TEGs result in device designs optimized for output power, which vary from conventional thermal impedance matching. The fill factor is hereby an important degree of freedom for the optimization. Furthermore, we demonstrate, that two materials with the same figure of merit zT will yield different output powers for the same device, if their thermal conductivities differ. This implies that considering the geometric limitations of the intended application already in the development of the printable thermoelectric materials can yield a larger power output for the device.

Energy harvesting schemes for internet of things: a review

<span lang="EN-US">As the <a name="_Hlk117855516"></a>internet of things (IoT) grows quickly, more people are interested in making wireless, low-power sensors. IoT systems currently use wireless sensors to collect reliable and accurate data in areas like smart buildings, environmental monitoring, and healthcare. Wireless sensors have typically been driven by batteries, which, although allowing for low total system costs, can have a significant impact on the whole network's lifetime and performance. The solution to this problem is energy harvesting (EH) from the environment. An EH is a technique for converting energy from an environmental source, such as heat, light, motion, or wind, into electric power. This paper describes many types of EH systems as well as some technological issues that must be solved before IoT energy harvesting solutions can be widely used.</span>

Mechanical intelligent wave energy harvesting and self-powered marine environment monitoring

Harvesting wave energy to power wireless sensors can realize marine environment monitoring. However, the low frequency and irregularity of waves, as well as the harsh marine environment, have become bottlenecks limiting the development of wave energy harvesting. Herein, we propose a novel concept of mechanical intelligent energy harvesting, i.e., adaptive external excitation and regulation of energy harvesting system by mechanical structure or mechanism rather than electrical components, and illustrate this concept by designing an irregular wave energy harvesting system. The proposed gravity-driven roller and seesaw-inspired structure are sensitive to low-frequency and irregular excitation, thereby wave energy can be more easily harvested into the system. Further, the bidirectional swinging of the seesaw is converted into a high-speed unidirectional rotation of the permanent magnet disc in one direction, resulting in a significant increase in the efficiency of electromechanical conversion. Moreover, symmetrical discs on both sides can rotate synchronously via magnetic coupling mechanism, which increases the magnetic flux in the coils for higher output power and the consistent phase of the voltage is conducive to the use of electricity. Besides, the rolling behavior is used by the triboelectric nanogenerator (TENG) to convert more mechanical energy into electricity without affecting the electromagnetic energy harvester. The experimental results show that the harvester can work effectively at the ultra-low frequency (0.1 Hz) and it can charge a 0.47 F capacitor to 5 V within 6 min to achieve a self-powered wireless marine environment monitoring system under simulated wave excitation. This work demonstrates that mechanical intelligent energy harvesting is a potential solution for irregular energy harvesting and self-powered Internet of Things (IoT).

Sustainable Microalgal Harvesting Process Applying Opuntia cochenillifera: Process Parameters Optimization

Microalgae harvesting by coagulation can use coagulant agents such as alum, synthetic polymers or biocoagulants. Biocoagulants have attracted the attention of researchers because they are natural, biodegradable, and promote high microalgal harvesting efficiencies. This study aims to optimize the harvesting of Chlorella vulgaris based on the dosage of the Opuntia cochenillifera extract and the choice of eluent for biopolymer extraction. The outdoor cultivation of C. vulgaris achieved a specific growth rate of 0.455 d−1 and a maximum biomass concentration of 1.28 gDW L−1. In order to harvest the microalgal biomass, the polymer present in the mucilage of O. cochenillifera was extracted using NaOH and HCl. Coagulation and sedimentation assays were performed with different coagulant dosages: 3.5, 5.9, and 8.2 g L−1. The maximum harvesting efficiencies using the acid and alkaline extract coagulant solutions were 80.8% and 99.5%, respectively, with a dosage of 3.5 g L−1. According to the results, the C. vulgaris biomass can be harvested with the mucilage from O. cochenillifera in acid and alkaline eluents. The application of this biocoagulant constitutes a sustainable solution for microalgal harvesting.

Switch-Beam Antenna Techniques for Bridge Structural Health Monitoring With GaAs-Based Solar Energy Harvesting

<bold xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">The structural health monitoring (SHM) of bridges with wireless sensor networks (WSNs) is addressed by leveraging two distinct but interrelated aspects: GaAs-based solar energy harvesting and switched-beam antenna strategies in combination with asynchronous media access control (MAC) protocols. The joint optimization of solar energy harvesting and switched-beam directional antennas at the nodes is considered and compared with an equivalent omnidirectional antenna network. To address the limited energy budget in battery-based sensor nodes which is a serious limitation in long-lived applications such as bridge SHM, an efficient solar harvesting solution is put forth based on the good performance of GaAs cells even under low-light conditions. Given the current state of the art in GaAs cells, single-junction cells were selected due to the cost of double-or triple-junction versions. The simulation model includes the residual energy capacity with GaAs-based solar energy harvesting of actual selected components (microcontroller, radio interface chip). The model was implemented on top of the Omnet<inline-formula> <tex-math notation="LaTeX">$++$</tex-math> </inline-formula> and Silvaco Atlas simulator. The comparative study in this article provides insights into realistic bridge SHM sensor networks, leveraging solar energy harvesting and switched-beam antennas.</b>

The Watershed House: A Water Harvesting Prototype For Vulnerable Communities

A potential answer to the call for a human right to sustainable and equitable housing, water access, and environmental justice may be found in the wings of a desert beetle. This paper presents a housing prototype integrating various water harvesting strategies and biomimetic solutions derived from the Namib beetle. An exploration of issues at the intersection of water access and equitable housing is presented through a literature review that demonstrates how housing conditions, access, and affordability are linked to a lack of infrastructural services, including water, which has subsequent health implications. The paper reviews both passive and active water harvesting opportunities for architectural integration. The paper concludes with a description of the prototype through a case study addressing the housing and water access needs of colonias communities in Texas, and sheds light on water access and housing affordability challenges, proposing architectural and policy strategies to address these issues. The speculative housing prototype integrates water harvesting solutions using a prefabricated kit of parts approach allowing for flexibility and adaptability across various communities where centralized infrastructure is technically or economically not feasible.

A novel feature for monitoring the enzymatic harvesting process of adherent cell cultures based on lens-free imaging

Adherent cell cultures are often dissociated from their culture vessel (and each other) through enzymatic harvesting, where the detachment response is monitored by an operator. However, this approach is lacking standardisation and reproducibility, and prolonged exposure or too high concentrations can affect the cell’s viability and differentiation potential. Quantitative monitoring systems are required to characterise the cell detachment response and objectively determine the optimal time-point to inhibit the enzymatic reaction. State-of-the-art methodologies rely on bulky imaging systems and/or features (e.g. circularity) that lack robustness. In this study, lens-free imaging (LFI) technology was used to develop a novel cell detachment feature. Seven different donors were cultured and subsequently harvested with a (diluted) enzymatic harvesting solution after 3, 5 and 7 days of culture. Cell detachment was captured with the LFI set-up over a period of 20 min (every 20 s) and by optimising the reconstruction of the LFI intensity images, a new feature could be identified. Bright regions in the intensity image were identified as detaching cells and using image analysis, a method was developed to automatically extract this feature, defined as the percentage of detached cell regions. Next, the method was quantitatively and qualitatively validated on a diverse set of images. Average absolute error values of 1.49%, 1.34% and 1.97% were obtained for medium to high density and overconfluent cultures, respectively. The detachment response was quantified for all conditions and the optimal time for enzyme inhibition was reached when approximately 92.5% of the cells were detached. On average, inhibition times of 9.6–11.1 and 16.2–17.2 min were obtained for medium to high density and overconfluent cultures, respectively. In general, overconfluent cultures detached much slower, while their detachment rate was also decreased by the diluted harvesting solution. Moreover, several donors exhibited similar trends in cell detachment behaviour, with two clear outliers. Using the novel feature, measurements can be performed with an increased robustness, while the compact LFI design could pave the way for in situ monitoring in a variety of culture vessels, including bioreactors.

Microalgae enrichment for biomass harvesting and water reuse by ceramic microfiltration membranes

Harvesting and water reuse are two critical issues for large-scale microalgae cultivation. Using two representative microalgae species, namely C. vulgaris and Scenedesmus sp., this study evaluates the performance of a ceramic microfiltration membrane to extract clean water for reuse and pre-concentrate the microalgae solution for subsequent harvesting. The results show that fouling was specific to each individual microalgae species due to the difference in cell properties (e.g. size, shape, and cell membrane). Importantly, membrane fouling could be efficiently mitigated by aeration and regular backwashing without any chemical addition. Aeration reduced the transmembrane pressure when filtering C. vulgaris and Scenedesmus sp. by 56 and 38%, respectively. In long-term performance experiments, C. vulgaris showed considerable membrane fouling over time; by contrast, Scenedesmus sp. showed negligible fouling. The results reaffirmed that membrane filtration efficiency was microalgae species-specific. Permeate water reuse for growing another batch of microalgae was also demonstrated using both species. Results reported here suggest that ceramic microfiltration membrane can simultaneously enrich the microalgae solution and recycle permeated water for microalgae cultivation.

Ethylated analogue of Zingerone: A new and eco-respectful preservative in cosmetics.

This article describes the eco-design of a new preservative in cosmetics based on bio-inspiration of natural extracts from traditional medicines. In order to reach the multiple specification targets, various structures have been synthesized and evaluated to select the one demonstrating broad antimicrobial spectrum with favorable environmental profile and application potential to a wide variety of formulas. In order to evaluate the antimicrobial activity of the synthesized structures, the method of the challenge test consisting in an artificial contamination of the sample with collection microbial strains and evaluation of the number of revivable microorganisms was used to select the most promising candidate. Validation of its antimicrobial potential was later confirmed on Gram positive and Gram negative bacteria, yeast and mold with measurement of its Minimum Inhibitory Concentration (MIC) in comparison with known preservatives. Environmental impact assessment of the selected candidate was achieved with the help of ready biodegradability and aquatic ecotoxicity tests performed according to appropriate Organization tes a strfor Economic Co-operation and Development (OECD) and European Union (EU) guidelinesy. Bio-inspired from turmeric and ginger extracts, an ethylated analog of Zingerone (EZ) with the chemical name 4-(3-ethoxy-4-hydroxyphenyl)butan-2-one demonstrates the strongest activity on Escherichia coli, Enterococcus faecalis, Pseudomonas aeruginosa and Candida albicans. Moreover, EZ shows a solubility in water two times higher than that of Zingerone thus increasing its interest as a potential preservative. Finally, its assessment of ready biodegradability and aquatic ecotoxicity in OECD-EU tests with a favorable environmental profile confirms its unique interest and fully justifies its use in cosmetic formulas as an eco-respectful preservative. Bio-inspiration based on technologies without noteworthy side effects but also on eco-design, particularly through the use of measures of potential environmental impact very upstream of a development, are two fundamental elements for the launching of new eco-friendly cosmetic ingredients. This approach has thus validated the strong potential of EZ as a preservative of eco-respectful formulas. The selection of EZ is also a very good example of the achievement of two key objectives targeted by cosmetic companies for the development of a novel active ingredient: environmental performance and technical performance.

Spatial variability of surface water runoff and sedimentary output of the Sartka Valley Basin using the KINEROS simulation model

Abstract: The amount of water seeping into ground is varied across the study area، so the central region have a rich groundwater reservoirs due to higher water seeping ratio into the ground. - Runoff is concentrated in the most northeastern parts of the basin، and this runoff is useful in the application of water harvesting methods of various types. It is useful in the design of small dams and ponds، then constructing a dam with medium capacity at the estuary of the basin in order to collect excess water of the study area. The study recommended establishment of weather station and hydrological cross sections to measure discharge of the catchment، it also recommend using the flood water to feed and recharge the underground stock and rising groundwater table. Forecasting the water yield and the sedimentary output that results from a rainstorm on the river basins has not taken a large place in the hydrological studies yet، so one of the unmeasured catchment of temporary flow (Sartaka basin) was chosen for this study، it locates the extreme southwest of Shaqlawa district. The basin originates from the southern slopes of Safin mountain، which is a tributary of the Gomaspan basin. Earlier but especially in the recent years the geography has witnessed using the application of modern methods، including quantitative programs and techniques، to reach more accurate results far from description and generalization. Therefore، the study seeks to find solutions for water harvesting and reducing the manifestations of water scarcity in the study area، by modeling and simulating the relationship between climatic variables on the one hand، and surface water runoff and sedimentary product on the other hand، through experimental and programmatic methods using the (KINEROS) tool. The importance of the study is solving the water scarcity in the region and reshaping and organizing the environment of the area for the sake of developing social life in general. This study has come to end with some conclusions as stated below: - The feeding source of the basin is rainwater، which falls and takes place in the valleys during the rainy season.

Elastic Piezoelectric Nanofibers Mats for Acoustic Energy Harvesting

One of the traditional clean-energy harvesting solutions is through transducing different mechanical stresses into electrical energy. Generally, the acoustic-to-electric energy conversion of still needs more research investigations to be applicable. In our work, we are targeting to fabricate elastic nanofibers mats via electrospinning method to be used for acoustic harvesting/sensing applications. The targeted mechanically-elastic nanocomposite includes polyvinylidene fluoride (PVDF), which is one of the most famous organic piezo materials, with blended thermoplastic polyurethane (TPU). As TPU supports higher mechanical allowed breaking strain. Then, the synthesized mat has been used as a target for mechanical stresses with resulted piezosensitivity of 667±220 mV/N. Then, the nanofibers mat has been targeted against acoustic signals with different amplitude and frequencies. It has been observed that the synthesized mats can detect or harvest acoustic signals and convert them into output electric voltage. According to acoustic sound input, the synthesized electrospun nanofibers detect output voltage up to 300 mV with increased input audible amplitude and frequency up to 6 kHz, where the harvested voltage has a saturation behaviour beyond that audible frequency. That can open the track for using such nanocomposites in energy harvesting applications from disposable facemasks, filters, and music/noise in different opened and closed areas.

Economic Incentives in Stormwater Management: A Study of Practice Gaps in Poland

Sustainable rainwater management is made possible, among others, by nationwide and local policies and regulations that create economic incentives. This article analyzes how existing economic instruments in Poland motivate property owners to make investments that manage rainwater on their own properties. Two types of investments were analyzed: bioswales as one of the lowest-cost green infrastructure measures in construction and operation, and the rainwater harvesting solution that uses rainwater to irrigate greenery. Simulation of this type of investment was undertaken in response to existing economic incentives—obtainable discounts of national and municipal rainwater drainage fees and municipal subsidy programs for rainwater management from three cities of different sizes selected from the Greater Poland province. Analyses were carried out for three types of development: different intensity, sealing of the land, and number of residents. The financial profitability of the investment was evaluated by determining the payback period, NPV, and benefit–cost ratio, taking into account the possible discounts in fees and investment subsidies in the variant analyses. It was shown that the incentive function of national fees for rainwater drainage is low, and that the incentive function of municipal fees and subsidies is higher, depending on the design of the fee (rates and discounts) and subsidy (directions and level of subsidies) systems.

Hydroelastic response and electromagnetic energy harvesting of square oscillators: Effects of free and fixed square wakes

The unbounded linearly increasing responses in galloping instability make sharp-edge oscillators a beneficial solution for bladeless energy harvesting. While the performance of single square oscillators has been the subject of several studies in the past, there is still little knowledge about their hydrokinetic energy performance in tandem configurations. An optimal oscillator should display high performance in a group when all bodies are free to harness energy. In this study, the energy harvesting performance of square oscillators is examined in multiple tandem configurations under free and fixed square wakes. The harmonic oscillator model is coupled with the electromagnetic transducer to evaluate the performance of the system at the optimum coupling coefficient. For a single galloping square, flow interference by a similar upstream square affects the fluid elastic response of the oscillator and degrades its overall energy harvesting performance. The upstream fixed wake is productive in terms of efficiency (123% increase) but counterproductive for the electrical current and electromagnetic power. The free square wake generally diminishes both the power and efficiency. For a double tandem oscillator device, the synergy of tandem configuration at close spacing improves the maximum efficiency of the energy harvester by 97% as compared to two separate isolated oscillators.

A Solar, Thermal, and Piezoelectric Based Hybrid Energy Harvesting for IoT and Underwater WSN Applications

Background: There has been an increasing interest in the research community regarding the development of new energy harvesting systems/architectures for sensor networks deployed at critical locations. Various types of energy harvesting techniques like solar, thermal, aquatic, and wind energy harvesting systems are popular in the research community. It has been found in a survey that a single energy harvesting technique is not enough for the wireless sensor network, especially when the nodes are deployed in critical areas, like volcanoes, underwater, ocean, rivers, etc. Objective: This study aimed to explore energy solutions for perpetual, battery-less, and critical places where human intervention is impossible. Method: In this study, a hybrid energy harvesting solution using solar, pressure, and thermal has been proposed. An optimized framework has been proposed, implemented, and analyzed for the underwater sensor network application. Furthermore, mechanical and electrical schematic models have been designed, implemented, and realized. Result and Discussion: The physical parameters of solar, thermal, and piezoelectrical transducers have been analyzed along with mathematical equations to find the best possible solutions for the optimized framework. Conclusion: The model was theoretically implemented and investigated, and it was found that 22.3KJ of energy can be extracted in 24hrs from the proposed design, which guarantees a perpetual life of the sensor node.

Intermittent-Aware Distributed Concurrency Control

Internet of Things (IoT) devices are gradually adopting battery-less, energy harvesting solutions, thereby driving the development of an intermittent computing paradigm to accumulate computation progress across multiple power cycles. While many attempts have been made to enable standalone intermittent systems, little attention has focused on IoT networks formed by intermittent devices. We observe that the computation progress improved by distributed task concurrency in an intermittent network can be significantly offset by data unavailability due to frequent system failures. This article presents an intermittent-aware distributed concurrency control protocol which leverages existing data copies inherently created in the network to improve the computation progress of concurrently executed tasks. In particular, we propose a borrowing-based data management method to increase data availability and an intermittent two-phase commit procedure incorporated with distributed backward validation to ensure data consistency in the network. The proposed protocol was integrated into a FreeRTOS-extended intermittent operating system running on Texas Instruments devices. Experimental results show that the computation progress can be significantly improved, and this improvement is more apparent under weaker power, where more devices will remain offline for longer duration.

Radiofrequency Energy Harvesting Systems for Internet of Things Applications: A Comprehensive Overview of Design Issues

Radiofrequency energy harvesting (RF-EH) solutions have evolved significantly in recent years due to the ubiquity of electromagnetic waves in any environment. This review presents a comprehensive report on autonomous wireless sensor (WS) design considerations based on RF-EH. The obtainability of RF-EH-WS is driven by development efforts in the areas of RF-EH circuit design, known as rectifying antenna (Rectenna), the minimization of the energy budget of WS (MEB-WS), and finally, power management modules (PMM). The PMM aims to optimize the energy efficiency of the WS. In addition to these three factors, examining the RF power levels harvested related to the rectenna feeding technique (RFT) is essential. Since we did not find any review presenting a holistic view of these design considerations, we strived to provide a detailed picture of recent advances and new enhancements in this review. To address this issue, this review gives an overview of the seminal and contemporary studies in the RF-EH-WS field. The IoT issues are also discussed in terms of their basic requirement to support reduced size or miniaturized smart objects, which are common matters in current applications of WS nodes. Potential open issues that might be considered for future research are also discussed in this article. For a more detailed description of all presented concepts, many significant references are provided for the readers.

Near-infrared light harvesting of upconverting Y2O3:Er3+ nanoparticles and their photovoltaic application

Light harvesting plays a significant role in the enhancement on photovoltaic performance. It is closely associated with the photocurrent of solar cells. It is possible to improve light harvesting by material substitution as well as expansion of absorptive edge. Therefore, upconversion characteristics is one of promising solutions for better light harvesting. Upconverting materials emit visible light which is available for photoconversion after they absorb invisible near-infrared (NIR) light. In this study, Er3+ doped Y2O3 (Y2O3:Er3+) nanoparticles were used as upconverting material. Its strong emissions of green and red light corresponding to 2H11/2 and 4S3/2 → 4I15/2 and 4F9/2 → 4I15/2 transitions were clearly demonstrated under NIR irradiation of 975 nm wavelength. These emissions were apparently absorbed by dye-sensitized electrode. Based on these results, Y2O3:Er3+ nanoparticles were introduced into dye-sensitized solar cells (DSCs). After incorporating Y2O3:Er3+ nanoparticles, photovoltage was increased due to its high band-gap energy of about 5 eV. On the other hand, the photocurrent was decreased because of the decrease in adsorbed dye amount and electron paths. However, the photoconversion edge was obviously expanded. As a result, DSC performance was enhanced with optimum upconverting particles. It exhibited an efficiency of 8.03%, which was higher than that of a conventional DSC.

Experimental Observation of the Multiple Higher-Order Extensible Topological States in Acoustic Systems

Recently, higher-order topological insulators with both gapped edge states and in-gap corner states, have been simulated and observed. However, multiple higher-order extensible topological states have not yet been witnessed. Here, we fabricate two acoustic samples, each consisting of double sandwichlike heterostructures, a sonic crystal with a gapless state is inset between two sonic crystals with opposite topological phases in each heterostructure. We theoretically simulate and experimentally obtain the higher-order extensible topological states, which are induced by the Jackiw-Rebbi mechanism, and also demonstrate the robustness of the higher-order extensible topological states via experiment and numerical simulations. The distributions of the pressure fields of the higher-order extensible topological states localized within a certain range of the vertical direction, rather than at a corner, and decay exponentially in the horizontal direction. At the same time, by adjusting the number of layers of the middle sonic crystal in the double acoustic sandwichlike structures, we witness the multiple higher-order extensible topological states protected by band topology. Although the width of the middle sonic crystal is limited by the size of the sample, we provide a feasible solution for different energy harvesting, and enrich the understanding of higher-order topological states.

On the Optimization of a Photo-Electrode: Interplay of Photoactive and Conductive Materials in a Lithium-Ion Photo-Battery

Green and sustainable devices that can harvest and store the solar energy along with delivering electricity during dark periods have garnered much attention. This is owing to solar energy being the best renewable source of energy for producing clean electricity that can potentially meet demand on a global scale.Although silica solar panels can harvest sunlight, they must be coupled with conventional batteries such as lithium ion batteries (LIBs) to store the collected energy. Organic dyes offer many advantages to silica panels. They are lighter, cheaper, more versatile, as well as a more sustainable harvesting solution. We therefore took advantages of the benefits of LIBs and an organic dye to lay the groundwork required for developing an all-in-one device that potentially can harvest sunlight and store the energy directly in the LIB.An organic dye was judiciously selected based on its known properties that meet the requirements for light harvesting and charge transfer with the LIB active components. We have established structure/property relationships that have confirmed the dye can be reduced by the battery’s electroactive components upon light absorption. This will be complemented by steady-state and time-resolved solid-state emission quenching studies. It will be shown that Raman spectroscopy can provide further insight in the effect of the photobattery architecture and the conductive surfaces on the charge transfer processes. This will be complemented with electrochemical studies, including galvanostatic cycling with the dye with various photo-cathode architectures to further understand the role of the microstructure in the electronic transfer. Systematically replacing various components of the LIB with their organic counterparts will also be presented to elucidate the photocharge mechanisms and lay the groundwork for an all-in-one photobattery.

Potentials for Sponge City Implementation in Sub-Saharan Africa

Despite the growing interest in implementing sponge cities (SPC), their potential is not yet being tapped in many fast-growing Sub-Saharan African cities. This is remarkable because SPC interventions can contribute considerably to increasing water safety and availability in a city. By means of a three-stage potential assessment, this study provides the first analysis of what concrete options can be identified for implementing the SPC concept in Sub-Saharan cities. The methodology was filled with information obtained especially from expert interviews, literature reviews, and satellite imagery. Thus, the analysis also considers what obstacles impede SPC implementation, and, in particular, what technical and socioeconomic constraints need to be taken into account. The cities of Hawassa (Ethiopia), Beira (Mozambique), Kigali (Rwanda), Ouagadougou (Burkina Faso), and Cotonou (Benin) are examined in detail. Additionally, a local SPC implementation was conceptualized and evaluated for two districts in Ouagadougou and Cotonou. The first finding is that, when geographical and socioeconomic aspects such as climatic patterns, migration flows, health risks, and existing infrastructure are sufficiently taken into account, SPC interventions would massively help African cities to mitigate current and urgent challenges such as water scarcity and urban flooding. In terms of water safety, the second key finding is that rainwater harvesting solutions at the household level could be implemented quickly; however, there would be substantial difficulties such as lack of financing and maintenance as well as claims of ownership, especially in informal settlements and slums. Thus, it seems quite promising to directly strive for a rapid “centralization” of SPC implementation in individual neighborhoods. This neighborhood approach paves the way for SPC measures to receive public acceptance and constant maintenance. When this mosaic of implementations comes together, many individual instances of SPC implementation can help to improve urban resilience and living conditions for the city dwellers as is here demonstrated for the districts in Cotonou and Ouagadougou.