Harvesting System Research Articles

Potential of coupled array harvester in enhanced energy harvesting.

Harvesting energy from nonlinear systems has been at the centre of research in the energy harvesting community. Many such proposed systems are single nonlinear harvester. While these systems show an increase in bandwidth of harvesting frequency, overall, they are not effective enough in power generation. This article studies power harvesting and frequency bandwidth characteristics of an array of harvesters. Multiple harvesters are considered with linear and nonlinear coupling between the harvesters. The phenomena of internal resonance (IR) and stochastic resonance (SR) are reported. The IR in multiple coupled nonlinear harvesters is explored using multiple-scale analysis. A parametric study is conducted to demonstrate the effect of coupling strength, frequency mistuning, innate nonlinearity and other parameters. The parametric study helped establish effective ways to increase bandwidth. Moreover, a stochastically loaded linearly coupled bistable harvester array is numerically analysed to find the effect of coupling strength and array size on the phenomenon of SR and on the system's harvesting performance. Through these studies, the potential of multiple coupled nonlinear harvesters in enhanced energy harvesting is demonstrated under both harmonic and stochastic excitation.This article is part of the theme issue 'Celebrating the 15th anniversary of the Royal Society Newton International Fellowship'.

A New Paradigm on Waste-to-Energy Applying Hydrovoltaic Energy Harvesting Technology to Face Masks.

The widespread use of single-use face masks during the recent epidemic has led to significant environmental challenges due to waste pollution. This study explores an innovative approach to address this issue by repurposing discarded face masks for hydrovoltaic energy harvesting. By coating the face masks with carbon black (CB) to enhance their hydrophilic properties, we developed mask-based hydrovoltaic power generators (MHPGs). These MHPGs were evaluated for their hydrovoltaic performance, revealing that different mask configurations and sizes affect their efficiency. The study found that MHPGs with smaller, more structured areas exhibited better energy output, with maximum open-circuit voltages (VOC) reaching up to 0.39 V and short-circuit currents (ISC) up to 65.6 μA. The integration of CB improved water absorption and transport, enhancing the hydrovoltaic performance. More specifically, MHPG-1 to MHPG-4, which represented different sizes and features, presented mean VOC values of 0.32, 0.17, 0.19 and 0.05 V, as well as mean ISC values of 16.57, 15.59, 47.43 and 3.02 μA, respectively. The findings highlight the feasibility of utilizing discarded masks in energy harvesting systems, offering both environmental benefits and a novel method for renewable energy generation. Therefore, this work provides a new paradigm for waste-to-energy (WTE) technologies and inspires further research into the use of unconventional waste materials for energy production.

Changes in the composition of grass and shrub layer plants in common oak stands since the closure of leaf canopy

Nowadays, there are threats of extinction of plant communities and individual plant species. Therefore, it is important to investigate the possibilities of restoring the composition of plants of different levels of forest phytocoenoses after clear-cutting in specific types of forest conditions. The purpose of the study was to establish the possibilities and features of restoring the species composition of plants of the grass and shrub layer, new growth and undergrowth after closing of canopies on common oak stands in fresh sugruds. Methods used: species accounting, comparison of species diversity at different sites, assessment of species abundance. It was established that the grass and shrub layer in closed forest stands consists of 54-57 species and it has a significant foliage cover – 60%. The base of the layer consists of 18-20 species. There is an increase with age in the value of the foliage cover of the main types of grass and shrub layer from 57-58% to 63-68%. It was found that the largest number of plants of the grass and shrub layer belongs to the forest ecological and coenotic group: in 9-10-year-old stands, 53.5% of species belong to the group, in 20-40-year-olds – 66.0%, and in 50-60-year-olds – 69.2%. It was found that the undergrowth consists of 4-6 species with a total closeness of 20-30% in crops of all age groups. The new growth consists of 6-8 species in forest stands of all age groups and their foliage cover ranges from 20-25%. The ratio of plants of different ecological and coenotic groups in oak stands of 50-60 years is quite close to overripe (130-140 years) natural stands. The practical significance of the study lies in the possibility of using the results in the practice of creating environmental protection facilities and justifying the systems of harvesting for the general use

An Analysis of Factors That Influence the Success of Flood Risk Management in Selected River Basins (FMSRB) Program in Banten Province and Maluku Province

FMSRB Program, under CPIU Directorate General of Regional Development Ministry of Home Affairs has successfully built 2,907 units of infrastructure, consisting of: (1) 152 units of retaining walls; (2) 24 units of reservoirs; (3) 265 units of drainages; (4) 56 units of rainfall harvesting system; (5) 46 units of retention wells; (6) 2,351 units of biopori; and (7) 13 units evacuation routes. The construction of infrastructure is in collaboration with the establishment of 4 KMSB forums in the regency, 140 KMSBs, and 140 waste banks in the community level. The success of program is primarily determined by 4 factors, including the success in the human resources management, collaboration among stakeholders, collaboration of structural and non-structural approaches, as well as the partnership development. Quantitatively, it is discovered that 55.70% of impact value indicates a very significant influence on flood control, whereas 36.80% states influential. For the construction of reservoir 57.50% of respondents state that it is high influence, whereas 33% state influential. In terms of rainfall harvesting system, 54.70% of respondents state highly influential, while 31.10% state influential. In Biopori, 60.40% of respondents state highly influential, whereas only 28.30% state influential. For retention well, 52.80% of respondents state very influential and only 38.70% states influential. In the meantime, the status of constructed infrastructure assets indicates that 65.10% are very good and 17.90% are good. Furthermore, the human resources management contributes β 0.141 with the influence of p-0,038 to the sustainability empowerment mediation. Collaboration among stakeholder is very good (59.40%) and good (25.50%). About gender and empowerment-based collaboration model, 65% of respondents fully agree and confirm, whereas only 35% agree. Meanwhile, collaboration among stakeholders is very helpful according to 65% of respondents and only 35% state helpful. As for structural and non-structural approaches collaboration, 82% of respondents state very helpful, and only 18% state helpful. For partnership, 59% of respondents fully agree with the partnership developed by FMSRB Program that uses the collaboration principle, and 41% agree. For sustainable program, advanced facilitation from the stakeholders to KMSB Forum, KMSB and Waste Bank is necessary. They will oversee utilization, maintenance, and development of the infrastructure for controlling flood.

Sustainable energy harvesting system for low-power underwater sensing devices

In marine scientific research, ocean monitoring is crucial where the battery powered sensor devices are placed under the water to collect different information like temperature, pressure, and turbidity in underwater sensor networks (UWSNs). Thus, keeping these devices active for longer periods is challenging. In the last decades, the piezoelectric transducer (PZT) material has been used widely for constructing more environmentally friendly energy harvesting systems. The PZT harvester offers a promising solution by eliminating the need for batteries for running devices in the future with less maintenance. The PZT harvester allows the system to generate higher voltage to run low-power devices. This paper designed and developed a new renewable energy harvester system using PZT transducers for running different types of underwater sensor devices like temperature, turbidity, and obstacle sensors. The proposed PZT-based energy harvester employs a two stage amplification model for generating higher voltage and current to run multiple devices. The sensing information collected from these sensors is transmitted to the cloud which is later utilized for analysis and decision making. Experiment results show the proposed PZT-based energy harvester can generate a voltage of 13 volts (V) and a current of 43.3 milliampere (mA) equivalent to 562 milliwatt (mW) which is very good to run multiple low-power underwater sensor devices.

Sugarcane harvesting systems in Brazil: Effects on soil carbon stocks and ethanol payback time

AbstractReplacing the burnt sugarcane harvesting system with unburnt sugarcane is important for the sustainability of the sugarcane sector in Brazil. Thus, quantifying the impact of the change in the sugarcane harvesting system on soil organic carbon (SOC) stock in Brazil is necessary, as it will allow the refinement of data on SOC, which is essential for the preparation of the national inventory of emissions and removal of greenhouse gases (GHGs), in addition to contributing to national public policies. We used data from both soil sampling and literature review in this study, resulting in 210 pairs of comparisons: 84 for the conversion from burnt sugarcane to unburnt sugarcane; 95 for the conversion from native vegetation to unburnt sugarcane; and 31 for the conversion from native vegetation to burnt sugarcane (NV–burnt), which we analysed using a mixed linear model. In Brazil and the South‐Centre region, burnt–unburnt conversion results in a progressive increase in SOC stocks over time, in surface and subsurface layers. Over 20 years, the NV–burnt conversion showed SOC losses between 15% and 32%, and the NV–unburnt conversion showed losses between 27% and 35%. SOC change rates showed gains of 0.32 and 0.59 Mg C ha−1 year−1 for burnt–unburnt, and losses ranging from 0.82 to 1.06 Mg C ha−1 year−1 for conversions from native vegetation. The time required to offset the negative carbon balance of the NV–unburnt conversion is 6.4 and 8.2 years, being shorter than the payback time of the NV–burnt conversion, which is 9.9 and 9.2 years, in the 0–30 and 0–50 cm layers, respectively.

A High-Efficiency Low-Cost Multi-Antenna Energy Harvesting System With Leakage Suppression

A High-Efficiency Low-Cost Multi-Antenna Energy Harvesting System With Leakage Suppression

Operator-Based Triboelectric Nanogenerator Power Management and Output Voltage Control.

In this paper, an operator-based voltage control method for TENGs is investigated, achieving output voltage tracking without compensators and uncertainty suppression using robust right coprime factorization. Initially, a comprehensive simulation-capable circuit model for TENGs is developed, integrating their open-circuit voltage and variable capacitance characteristics. This model is implemented to simulate the behavior of TENGs with a rectifier bridge and capacitive load. To address the high-voltage, low-current pulsating nature of TENG outputs, a storage capacitor switching model is designed to effectively transfer the pulsating energy. This switching model is directly connected to a buck converter and operates under a unified control strategy. A complete TENG power management system was established based on this model, incorporating an operator theory-based control strategy. This strategy ensures steady output voltage under varying load conditions without using compensators, thereby reducing disturbances. Simulation results validate the feasibility of the proposed TENG system and the efficacy of the control strategy, providing a robust framework for optimizing TENG energy harvesting and management systems with significant potential for practical applications.

Optimizing Building Orientation for Passive Cooling

This research paper explores the application of passive design strategies in three museums in Lagos, Nigeria: The National Museum, Jaekel House, and the Heritage Museum in Badagry. The study focuses on building orientation as a key passive design strategy and evaluates its effectiveness in enhancing energy efficiency and thermal comfort in tropical climates. With the use of data collection from Google Earth Pro, a comparative analysis examines the architectural features and design elements of each museum, highlighting their use of building orientation, shading devices, and landscaping to optimize passive cooling and natural lighting. The innovative layout and strategic orientation of the National Museum demonstrate a successful integration of passive design strategies, while Jaekel House's use of deep overhangs and vegetation showcases a deliberate commitment to sustainable architecture. The Heritage Museum in Badagry, with its historical significance, presents an intriguing case study for passive design. While limited information is available, satellite imagery suggests an optimal orientation for passive solar design, complemented by deep overhangs and a reflective roof. The findings suggest that the three museums can benefit from further enhancements to their passive design strategies, including the integration of renewable energy sources, smart building systems, green roof systems, and water harvesting and management systems. In addition, educational initiatives can raise awareness and promote sustainable practices among visitors and the local community.

Harvesting Energy from Rainfall: Initial Study by Exploring Diverse Piezoelectric Array Configurations for Enhanced Electricity Generation in Proteus Software

This paper presents an innovative approach to designing and analyzing a simulated piezoelectric energy harvesting system for electricity generation, employing various array connections using Proteus software. The ingenious concept of harnessing energy from rainfall through piezoelectric technology has become an exciting way to turn a common natural occurrence into a possible power source. The rainfall energy harvesting introduces a novel approach that capitalizes on the mechanical energy imparted by raindrops as they strike surfaces, such as rooftops, pavements, or specially designed structures. This study explores distinct piezoelectric connection types to determine their impact on output voltage, focusing on applications such as rechargeable battery and LEDs. The system begins by harvesting vibration and applying it to the piezoelectric disc. The investigation prioritizes identifying the optimal array connection design. Array configurations of series (S), parallel (P), and combination of series-parallel (SP) are assessed in the simulation. Notably, the series connection of 10 units of piezoelectric elements yielded the highest output voltage at 8.5V. The findings provide valuable insights into finding the optimal array connections in enhancing piezoelectric electricity generation. This research contributes to the leading of potential applications of piezoelectric energy harvesting from rainfall, offering insights into a greener and more self-sufficient energy future.

Optically manipulated nitrate-salt-based direct absorption solar collectors for a photothermal energy harvesting system

This study introduces a nitrate-salt-based direct absorption solar collector (DASC) for a photothermal energy harvesting system with efficient solar energy harvesting and the reduction of thermal radiation loss. Investigations of the optical properties of snow-like solid-state binary nitrate salt in solar and thermal infrared (IR) spectral regions were first conducted in this study. Research revealed that the solid-state binary nitrate salt showcases high solar reflectivity (>90 %) and infrared emissivity (∼0.85), leading to a cooling power of 36.4 W m−2. This implies pure solid salt cannot gain energy from solar illumination. To tackle this, the proposed system incorporated nano graphite and a hot mirror. Consequently, the absorbed solar energy increased from 67.6 W m−2 to 898.7 W m−2, resulting in a heating power of 794.0 W m−2 under AM 1.5G solar irradiance. With the proposed approaches, melting the salt with lowest solar concentration ratio of 15 (∼12.5 kW m−2) was achieved.

Protecting ancient water harvesting technologies in India: strategies for climate adaptation and sustainable development with global lessons

IntroductionAncient water harvesting systems, such as those from the Indus Valley Civilization (~3500 BCE), have been vital for irrigation and climate resilience, especially in arid regions. One such prominent system in South Asia, called tank irrigation, initially thrived through community management but declined post-independence due to colonial policies and neglect in Sri Lanka and India. This study evaluates current policy frameworks and rehabilitation programs to enhance the resilience of these systems in India, develop strategies for their protection and adaptation to climate change, and integrate global lessons for sustainable development.MethodsA systematic meta-analysis of grey literature was conducted to aggregate data on policy constraints. Policy analysis involved detailed investigations of relevant documents, regulations, and comparative analyses of frameworks at regional and national levels. Pilot projects on tank rehabilitation were assessed through reported case studies and field surveys to gauge impact. Thematic analysis was used to explore the global potential of these systems in climate resilience and overall environmental sustainability.ResultsThe analysis showed that pilot projects for tank rehabilitation had limited success in achieving sustainability under current climate conditions. Tank irrigation systems are crucial for adapting to extreme weather, including floods, droughts, and heat waves, replenishing groundwater, reducing soil erosion, and ensuring reliable water supplies. Traditional water harvesting technologies support 17 Sustainable Development Goals (SDGs), including clean water access, hunger reduction, gender equality, and climate action. Integrating AI and machine learning in water management benefits disaster response, while eco-tourism aids system maintenance and cultural awareness.DiscussionThe study underscores the need for policy reforms to enhance tank rehabilitation and institutional arrangements. It calls for increased beneficiary participation and constitutional recognition of current practices. Strategic, national-scale assessments and resilience targets are recommended to improve the effectiveness of such water harvesting systems in mitigating natural hazards and enhancing environmental services.

Towards Sustainable Water Use in Two University Student Residences: A Case Study

This research is focused on the water usage patterns in two student residences—one for male students (Residence I) and the other for female students (Residence II). Surveys and measurements of flushing cisterns, taps, and shower flows were conducted to understand water use behaviors. Scenario 1 proposed replacing washbasin and kitchen taps and installing flow reducers in showers, while Scenario 2 combined Scenario 1 with a rainwater harvesting system for recharging flush cisterns. Showers were found to be the most water-consuming devices, accounting for 46% and 61.41% of water consumption in Residences I and II, respectively, followed by kitchen taps (31.51% in Residence I and 11.52% in Residence II). The flushing cistern consumption was 7.02% in Residence I and 13.22% in Residence II. The implementation of Scenario 1 anticipates a 13% reduction in total water consumption in Residence I and a 10% reduction in Residence II. The reduction in hot water consumption would result in a decrease in annual electricity consumption by 27.8% and 23.06% in Residence I and II, respectively. With the implementation of Scenario 2, the total potential water savings for Residence I could increase to 19.98%, and for Residence II, it could rise to 23.17%. The proposed measures aim to enhance water sustainability in these buildings and can be replicated elsewhere.

Dumbbell-shaped piezoelectric energy harvesting from coupled vibrations

This paper presents a novel dumbbell-shaped piezoelectric energy harvesting from vortex-induced vibration (VIV) and galloping. The designed harvester system leverages the coupled vibrations to improve the output performance. The conceptual design of the dumbbell-shaped harvester system is first developed, the theoretical model of the harvester is then established, three-dimensional simulation analyses are conducted, and the prototypes of the harvester that combines a cylinder and a cuboid are finally manufactured. The effect of the cylinder lengths and airflow velocity on the harvesting characteristics is explored. The results demonstrate the derived mathematical model is fully verified through experimental method. VIV occurs in the 0.5D and 1D dumbbell-shaped harvester systems at lower airflow velocities, while galloping takes place at higher velocities, both of which contribute to increase the output performance. In contrast, the 1D - 3D dumbbell-shaped harvesters demonstrate a VIV behavior only and suppress vibration. The maximum voltage generated by the 0.5D harvester is 12.03 V at 4.29 m s-1, which is 11.18 % higher than that of a single cuboid harvester. The vorticity fields illustrate the vortex shedding mode and intensity, as well as reveal the underlying influence mechanism.

On the Necessity for Improving Water Efficiency in Commercial Buildings: A Green Design Approach in Hot Humid Climates

Water, a fundamental and indispensable resource necessary for the survival of living beings, has become a pressing issue in numerous regions worldwide due to scarcity. Urban areas, where the majority of the global population resides, witness a substantial consumption of blue water, particularly in commercial buildings. This study investigates the potential for enhancing water efficiency within an ongoing high-rise office building construction situated in a tropical climate. The investigation utilizes the green building guidelines of leadership in energy and environmental design (LEED) through a case-study-based research approach. Strategies included using efficient plumbing fixtures (such as high air–water ratio fixtures and dual-flush toilets), the selection of native plants, implementing a suitable irrigation system, introducing a rainwater harvesting system (RWHS) and improving the mechanical ventilation and air conditioning (MVAC) system. The results showed a 55% reduction in water use from efficient fixtures, a 93% reduction in landscaping water needs and a 73% overall water efficiency with a RWHS from the baseline design. Additionally, efficient cooling towers and the redirection of condensed water into the cooling tower make-up water tank improved the overall water efficiency to 38%, accounting for the water requirements of the MVAC system. The findings of this study can contribute to more sustainable and water-efficient urban development, particularly in regions facing water scarcity challenges. The significance of these findings lies in their potential to establish industry standards and inform policymakers in the building sector. They offer valuable insights for implementing effective strategies aimed at reducing blue water consumption across different building types.

The Advancement of Artificial Intelligence's Application in Hybrid Solar and Wind Power Plant Optimization: A Study of the Literature

The harnessing of solar, wind, and hydroelectric energy sources has rendered them easily accessible renewable resources, owing to their abundant availability. There is a growing body of research evincing interest in the deployment of hybrid renewable energy systems. Over recent decades, adopting hybrid technologies has engendered a positive trend, marked by broader considerations of configurations and applications within these systems. This study analytically examines the potential of hybrid solar and wind energy harvesting devices. As such, the project aims to extensively evaluate relevant literature and statistical analysis of data extracted from journal papers published between 2004 and 2023. A specific objective is to develop a complete database matrix surrounding multiple categories, including component configurations, methodological approaches, and supporting software infrastructures. Moreover, an assessment of the socio-economic, environmental, and ecological impacts of these systems is undertaken to ascertain their salience. Furthermore, this inquiry delves into the optimization strategies of these systems leveraging artificial intelligence methodologies. Critical lacunae identified during this review pertain to more emphasis on optimization metrics for PV-wind hybrid energy systems, impeding a holistic understanding of their implications on energy, economics, environment, and society. Our findings underscore prevalent methodologies such as computational modelling utilizing software suites like MATLAB/Simulink, HOMER, and others to derive empirical data. Additionally, parametric analyses emerge as the predominant approach, characterized by the application of algorithms such as Particle Swarm Optimization (PSO), Fuzzy Logic Control (FLC), and Genetic Algorithms (GA), among others. PV-wind hybrid energy systems are classified into autonomous and grid-interconnected configurations, with primary components comprising PV-wind generators. The anticipated trajectory suggests a burgeoning development of these hybrid energy harvesting systems, underpinned by their potential as clean, sustainable, and eco-friendly energy sources.

Green Wearable Sensors and Antennas for Bio-Medicine, Green Internet of Things, Energy Harvesting, and Communication Systems.

This paper presents innovations in green electronic and computing technologies. The importance and the status of the main subjects in green electronic and computing technologies are presented in this paper. In the last semicentennial, the planet suffered from rapid changes in climate. The planet is suffering from increasingly wild storms, hurricanes, typhoons, hard droughts, increases in seawater height, floods, seawater acidification, decreases in groundwater reserves, and increases in global temperatures. These climate changes may be irreversible if companies, organizations, governments, and individuals do not act daily and rapidly to save the planet. Unfortunately, the continuous growth in the number of computing devices, cellular devices, smartphones, and other smart devices over the last fifty years has resulted in a rapid increase in climate change. It is severely crucial to design energy-efficient "green" technologies and devices. Toxic waste from computing and cellular devices is rapidly filling up landfills and increasing air and water pollution. This electronic waste contains hazardous and toxic materials that pollute the environment and affect our health. Green computing and electronic engineering are employed to address this climate disaster. The development of green materials, green energy, waste, and recycling are the major objectives in innovation and research in green computing and electronics technologies. Energy-harvesting technologies can be used to produce and store green energy. Wearable active sensors and metamaterial antennas with circular split ring resonators (CSSRs) containing energy-harvesting units are presented in this paper. The measured bandwidth of the matched sensor is around 65% for VSWR, which is better than 3:1. The sensor gain is 14.1 dB at 2.62 GHz. A wideband 0.4 GHz to 6.4 GHz slot antenna with an RF energy-harvesting unit is presented in this paper. The Skyworks Schottky diode, SMS-7630, was used as the rectifier diode in the harvesting unit. If we transmit 20 dBm of RF power from a transmitting antenna that is located 0.2 m from the harvesting slot antenna at 2.4 GHz, the output voltage at the output port of the harvesting unit will be around 1 V. The power conversion efficiency of the metamaterial antenna dipole with metallic strips is around 75%. Wearable sensors with energy-harvesting units provide efficient, low-cost healthcare services that contribute to a green environment and minimize energy consumption. The measurement process and setups of wearable sensors are presented in this paper.

Development of an effective rainwater harvesting system using sponge concrete

ABSTRACT Conventional concrete systems for rainwater harvesting often face challenges with water absorption and clogging. This study proposes an innovative approach: sponge concrete. By integrating absorbent sponge pieces, this method enhances rainwater absorption, overcomes limitations of conventional concrete, and improves water management during rainfall. Five different types of sponges were evaluated for their water absorption capabilities and the quality of water passing through them, assessed based on parameters such as pH, dissolved oxygen (DO), total dissolved solids (TDS), and electrical conductivity. Concrete was cast using these sponges to investigate properties such as density, void ratio, and compressive strength with various mix proportions. Among the sponges tested, the one with the lowest density showed the best water absorption results. The quality of water passing through all sponges remained within safety standards. A lower water-to-cement (w/c) ratio proved effective for achieving higher void ratio and lower density which is required for thereby achieving higher water absorption capacity. Although a higher void ratio resulted in relatively lower compressive strength, incorporating supplementary cementitious materials mitigated this issue to some extent. Hence, this study suggests that sponge concrete provides a promising solution for enhancing rainwater harvesting efficiency, offering an environmentally sustainable alternative to conventional concrete systems.

Carbon footprint of piezoelectrics from multi-layer PZT stacks to piezoelectric energy harvesting systems in roads

Piezoelectric energy harvesting devices (PEHDs) for road installation are being researched as potentially low-emission electrical generators, but their life cycle greenhouse gas (GHG) emissions must be assessed to guide their design and implementation toward minimizing their carbon footprint. Parametric life cycle assessments (LCAs) of a PEHD, its generator, and the piezoelectric material were performed using data from a pilot-scale PEHD installation. The GHG emissions of the lead zirconate titanate (PZT) piezoelectric stack were determined to be lower than previously reported in the literature at 10.81-15.90kg CO2eq/kg piezoelectric. The GHG emissions of electricity generated by a PEHD range from 48.65-588.63g CO2eq/kWh, spanning from similar to renewables to slightly higher than electricity from natural gas. Sensitivity analysis indicated that spatial parameters and the device lifetime had the largest influence on the LCA results. PEHDs installed on roads show potential to be low-GHG emission energy systems.

Feasibility analysis of using short-term rainfall time series to evaluate rainwater harvesting systems considering climate change

Employing recent short-term historical rainfall data may enhance the performance of rainwater harvesting systems (RWHs) in response to climate change. However, this assumption lacks extensive research, and the evaluation of RWHs currently relies on long-term historical rainfall time series. This study evaluates the feasibility of this assumption and aims to identify the optimal rainfall time series for evaluating RWH performance under climate change. We evaluated RWHs in residential buildings across 16 Japanese cities utilizing historical rainfall time series of varying lengths and 30-year predicted rainfall time series. The minimum rainfall time series length was obtained based on the similarity index between the evaluation results for historical and future periods. The corresponding optimal series can be determined from the distribution of similarity indices in the minimum length. Finally, we introduce supply pressure indices (SPIs) to summarize the rainfall characteristics of these optimal rainfall time series. Our findings highlight that the minimum rainfall time series length increased from 1 year to 30 years as building non-potable water demand rose and city locations varied. Utilizing rainfall time series incorporating recent rainfall data yielded more dependable evaluation results for RWHs under climate change. These optimal rainfall time series share common characteristics with SPIs ranging from 5.37 to 17.87 mm/d, contingent on the local rainfall patterns. Our study concludes that utilizing recent short-term historical rainfall data is feasible to evaluate and design RWHs under climate change.