Design of an Integral Simulation Model for Solar-Powered Seawater Desalination in Coastal Communities: A Case Study in Manaure, La Guajira, Colombia

Abstract

The provision of potable water or water with physical, chemical, and microbiological characteristics suitable for consumption is essential for human survival. However, numerous communities in the coastal areas of Colombia still lack access to clean and safe water sources. To address this challenge in many communities, desalination emerges as a promising solution. In this regard, this article focuses on the evaluation and proposal of an integrated simulation model for solar-powered water desalination in coastal communities, with particular attention to water quality aspects, as well as potential impacts on health and the environment. To carry out a comprehensive assessment, the intention is to design a simulation model using tools such as Homer Pro, IMSdesign, and MATLAB, leveraging data on living conditions and water quality in La Guajira, as well as publicly available information on the best desalination practices in coastal communities and following current Colombian regulations within the framework of health and environmental care. This model will allow for a detailed analysis of key factors and impacts in the implementation of solar-powered desalination systems, considering the conditions of the case study in Manaure, La Guajira, Colombia. Through this design, it facilitates the understanding of technical and operational aspects, as well as exploring efficient energy solutions through the integration of renewable sources, with the purpose of mitigating the challenges associated with high energy consumption and reducing both costs and the environmental and human health impact inherent in these desalination processes.

1. Introduction

The high demand for water resources has led to the search for new alternatives for obtaining water for human consumption and, throughout history, various technologies have been developed to meet this goal. Among these options is the desalination of seawater. This treatment has provided an option for various populations facing water deficits. However, various hypotheses have been raised about the effects of these techniques and their impact on health and the environment, leading to one of the objectives of this research, which is to conduct a literature review regarding the treatment of saline water, the technology developed, the effects and mitigations on the environment, and the impact on consumer well-being worldwide, for the design of a solar-powered desalination simulation model for coastal communities.

In this line of thought, when it comes to seawater, it is known to have a high content of dissolved salts. Therefore, to render it potable, it is necessary to remove the salts almost entirely to obtain water suitable for agricultural, industrial, and drinking purposes [1].

The fundamental premise underlying desalination is the water cycle, where solar radiation plays a significant role in the process, eliminating impurities and elements do not present in rainfall, as in distillation, which essentially involves separating materials and components into various byproducts [2]. This occurs in desalination, which is more simply defined as “the removal of salt from saline water” [3].

The model developed in this study integrates advanced tools such as HOMER Pro, IMSdesign, and MATLAB, enabling a comprehensive evaluation that simultaneously addresses the economic, environmental, and human health impacts associated with solar-powered desalination systems. This integration is particularly noteworthy for its ability to optimise the energy efficiency and technical performance of the system while quantifying secondary effects on the environment and local communities. Unlike previous approaches, which often focus exclusively on technical or economic aspects (2; 63), the present work adopts a multidimensional framework that identifies sustainable solutions through a holistic perspective.

Moreover, this model is specifically applied to Manaure, La Guajira, an area characterised by its unique conditions: high solar irradiance, limited water infrastructure, and a vulnerable community heavily reliant on unsafe water sources. By incorporating these variables, the model not only addresses a critical local issue but also establishes a replicable framework for similar coastal communities worldwide. This methodological combination represents a significant contribution to the design and assessment of sustainable desalination systems. This foundational understanding supports the application of reverse osmosis (RO) technology (for ease of understanding, a list of terms and abbreviations is included in Nomenclature), as a cornerstone of the proposed model.

On the other hand, it is important to highlight that RO desalination is a process that reverses the natural flow of osmosis to separate impurities from water and is a leading technology in this field. However, RO comes with some drawbacks, such as high specific energy consumption, reaching up to 4 kWh/m³, and membrane fouling, which requires chemical cleaning. It is worth noting that RO is the most widely used desalination technology worldwide so far because it still has the cheapest production cost per volume of freshwater (m³). On the other hand, rapid industrialisation, energy scarcity, and power outages lead to high energy demand [4].

These factors have led to the evaluation and implementation of new technologies that provide fresh solutions to water scarcity. Innovation in the water desalination sector has shown a rise in recent years, with the exploration of new alternatives in various areas such as new processes/methods, fuels, and supply sources, and research enabling market growth, which currently leans mainly towards thermal treatments and reverse osmosis [5].

Due to the rapid evolution of reverse osmosis (RO) desalination as a widely applied treatment technique, multiple questions have also been raised about its potential impact, initially associated with high energy consumption and subsequent concerns about environmental, social, and economic effects [6].

Doubts have also been raised regarding the safety of the produced water and its effects on consumer health. This is because studies with unanswered questions have shown uncertainties about the techniques used. For instance, according to research conducted, this method provides freshwater that often lacks essential minerals for agricultural production processes and consumer health [7].

For this reason, the simulation of desalination processes and energy processes plays an essential role in understanding complex systems that combine potable water production with energy generation. In the quest for sustainable solutions to supply clean water to coastal communities, this strategic integration of desalination and energy generation has become a crucial approach [8]. Through simulation, it is possible to accurately and comprehensively evaluate how these two processes interact, identify opportunities for improvement, and make informed decisions to achieve more efficient and environmentally friendly operation [9].

Due to the aforementioned reasons, it is of vital importance to conduct this type of research that allows us to understand, evaluate, and assess the impacts of this technique, thus providing better tools and/or models aimed at formulating and enriching environmental regulations. These regulations would reduce vulnerability to water deprivation while addressing the risk of poor water quality. This is where research plays a pivotal role, as the collection of empirical data facilitates the development of guidelines and recommendations for the implementation of policies and processes aimed at improving the availability of suitable water resources [10].

Literature Review on Impact Caused by Desalination Technologies

The process of treating highly saline water to obtain potable water, known as desalination, employs various technologies. These technologies offer different energy consumption profiles, which typically represent the most significant component of production costs, usually around 60% of the total [11]. Other considerations include installation and maintenance costs, product quality, environmental effects, etc. However, they all share the common goal of reducing concentrations of dissolved salts in brackish water [12]. Choosing the appropriate technology requires evaluating different aspects, given the variable characteristics of seawater, such as its salinity ranging from brackish to hypersaline [13].

Systematic studies indicate that desalination practices for seawater and their stabilisation should ensure that the overall process does not significantly reduce the total intake of nutrients such as calcium, magnesium, and fluoride. This is because water desalination treatment processes can affect mineral concentrations, triggering calcium and magnesium deficiencies, and posing health risks [14]. In the case of irrigating crops with desalinated water low in magnesium, it has been observed that crops develop symptoms of magnesium deficiency that could lead to plant death. A clear example is the reduced tomato yield by 10% to 15% [15].

The use of these technologies worldwide is distributed as follows: thermal technologies account for approximately 25%, dominating the Middle East where the most commonly used methods are multiple-effect distillation and multi-stage distillation [16], membrane technologies cover around 69%, with nanofiltration and electrodialysis constituting 3%. The major producers of desalinated water are Saudi Arabia, the United States, and the United Arab Emirates [17].

In comparison to other technologies, multiple questions have arisen regarding their environmental effects due to their high energy consumption, with most of them relying on fossil fuels, which trigger various environmental impacts such as high gas emissions [17]. This is because desalination processes involve direct emissions from in situ sources and indirect external emissions [18].

Among the most commonly used and applied technologies in coastal areas worldwide, which may be applicable to the context of Colombian coastal zones, are Reverse Osmosis Desalination, a technology that employs a semi-permeable membrane to separate salt and other contaminants from seawater; Thermal Distillation, involving the evaporation of seawater followed by condensation of the vapor to produce freshwater; and Reverse Electrodialysis, using electrically charged membranes to remove salt from seawater [9].

In recent years, increasing attention has been given to the potential use of renewable energies for small-scale desalination in remote communities. The combination of renewable energy sources such as solar, wind, and geothermal with desalination systems appears to be a promising solution to address water scarcity. This solution could also be viable for tackling climate change and water scarcity in coastal communities in Colombia [19].

2. Background

Colombia is a country with potable water issues in some coastal areas due to freshwater scarcity. The regions, most vulnerable to potable water supply - are concentrated in the Andean region, the Atlantic coast, and the island of San Andrés. Pueblo Viejo is a small town located in the Magdalena department (Atlantic coast). It covers an area of approximately 678 km² and has a population of around 30,000 inhabitants. Currently, the municipality does not have sufficient water supply systems [20].

In Colombia’s coastal areas, alternatives for desalination have been proposed for small communities, such as the municipality of Manaure in La Guajira, where the water company operates a desalination plant with a production capacity of 950 m³/day. This plant employs a pre-treatment process involving pressure filters and microfiltration, followed by reverse osmosis treatment. However, the municipality lacks adequate distribution networks, leading to water supply to the community being carried out via tanker trucks [8]. This method is costly for low-income communities, despite their high solar and wind potential, as well as their access to seawater. Similar conditions are found in other communities in the Caribbean region, spanning departments such as Magdalena, La Guajira, Atlántico, Bolívar, and Sucre, among others.

The desalination process via reverse osmosis currently faces another challenge, namely the high volume of waste generated during the water desalination process. This is due to a conversion factor determined by the type of membrane and pump used, resulting in a percentage of desalinated water and another of reject water, also known as brine [21]. Typically, this brine is discharged back into the sea. However, if not properly treated, it can have adverse effects on the marine environment due to its high concentration of salts and chlorides. Therefore, simple treatments such as dispersing it through surface discharge to facilitate rapid dissolution in the sea are necessary to prevent damage to the marine environment.

The reverse osmosis desalination process still presents some weaknesses in its application, such as high energy consumption and the generation of brine, prompting the ongoing search for method improvement. This has led to the exploration of new alternatives. It is worth highlighting that membrane use began in the 1930s; however, it was not until the 1960s that research into reverse osmosis began. This procedure revolutionised the desalination process, as it is a system known for its efficiency and high performance, making it the most widely used method globally today [7].

3. Materials and Methods

The proposed methodology encompassed a comprehensive approach to assess the economic, environmental, and human health impacts of desalination technologies applied to coastal communities worldwide, along with the feasibility of a solar-powered desalination system in the coastal community of Manaure, La Guajira, Colombia. This methodology is divided into key stages ranging from literature research on desalination technologies and data collection to simulation and economic evaluation, as well as assessing human health and environmental impacts. Each stage focuses on key aspects vital for addressing the research question: how can a comprehensive simulation model be designed to effectively incorporate solar energy for water desalination, considering economic, environmental, and human health aspects, aiming to improve sustainable access and water quality in coastal communities, using the case study in Manaure, La Guajira, Colombia? This also involves the development of potential solutions in the La Paz community in Manaure, La Guajira, allowing for a complete assessment of the potential in this coastal region. The stages of this methodology are detailed below:

3.1. Background Literature Review on the Impact Caused by Desalination Technologies

In this initial stage, the scope or boundaries of the research object were established. On this occasion, it was deemed necessary to focus on the analysis of numerous research works on the desalination process in coastal areas of Colombia and the available technologies worldwide, with a focus on technological evolution and the impact on the environment and consumer health.

3.2. Data Collection

With an understanding of desalination in Colombia and global background, the data collection stage proceeded for the selected case study in the community of La Paz, Manaure, La Guajira, Colombia. This involved gathering demographic and geographic data of the region, water availability and quality in the area, as well as collecting information on solar radiation and other environmental parameters related to energy potential. Additionally, current regulations governing water quality for human consumption and environmental impact were also compiled.

3.3. Development of Simulation Model

In this stage, the IMSdesign v2.231.90 tool was utilised to design a reverse osmosis desalination system specifically tailored to the conditions of Manaure. With the results from this software, projecting specifications of input and output flows, equipment to be used, and energy consumption of the plant, the energy supply system (Photovoltaic Solar System) was designed in HOMER PRO v3.14.5. This software is used for techno-economic evaluation of energy systems to power the desalination plant. Finally, an algorithm was developed in MATLAB vR2023b for the integration and analysis of these results in terms of economics, environmental impact, and human health in line with current Colombian regulations.

This simulation framework was built based on the work described in [22] and further shared through “Risk know-how around the world: People helping each other talk about risk” [23]. In this initiative, the Engineering Research Institute at the Universidad Cooperativa de Colombia, with the support of the BERSTIC Network, developed a framework called CARED (Community, Water-Renewable Energies, Diversity). A key component of this approach is to bring together all stakeholders in the projects, including representatives from industry, academia, government, communities, and international cooperation. This framework was informed by fieldwork conducted with communities such as Manaure and provided the foundation for the simulation model used in the current study.

The simulation model for this case study comprised various stages or process simulations, as depicted in Figure 1. These stages range from organising input information in compliance with regulations for the use of available water resources and the energy potential of the area to detailed simulation of the desalination plant and the electrical supply system using available commercially tools already validated. Additionally, the model includes an analysis of environmental adversities and human health impacts.

4. Results

This section presents the achievements of this research, ranging from the literature review on desalination practices and potential economic, environmental, and human health impacts (found in the introductory section), to the design of a simulation model that integrates all these aspects under the framework of current Colombian regulations. The results provide a comprehensive and detailed overview of the evaluation of a solar-powered desalination system in the coastal community of Manaure, La Guajira, Colombia. Through a combination of data collection, analysis, and simulations, the technical, economic, and environmental aspects of a possible solution to supply drinking water to the coastal community are examined.

4.1. Data Collection

4.1.1. Demographic and Geographic Data

The conditions in which the La Paz community, the focus of this study located in Manaure, La Guajira, currently reside, as depicted in Figure 2, are experiencing challenges related to potable water. This issue has gained international priority, given that the Colombian state’s neglect has resulted in decades of decline for the region, with inhumane living and health conditions. In addition to its academic and research purposes, this article carries a social significance, urging awareness of the adverse situations faced by the residents [24].

The county of La Guajira is characterised as one of the driest regions in the country, attributed to the sparse vegetation evident in the area, specifically in the highlands. However, in lower Guajira, better climatic conditions prevail, allowing for increased agricultural and livestock activities (Right to Water and Territory).

The design of this desalination plant was specifically undertaken to provide potable water to the Rural Ethnoeducational Institution La Paz, a school catering to over 500 Wayuu children. In the current context, during their school day, these children receive only one or two glasses of water in exchange for education and other academic activities such as entrepreneurship or sports. The water is either collected from expensive tanker trucks purchased by the institution or obtained from wells where the water is in very poor condition.

The estimated water consumption for each child in the school is approximately 1 L per day, resulting in a total school consumption of around 550 L per day. This figure includes an additional 10% adjustment, based on information gathered from previous experiences with the community.

Adjusting this demand based on Colombian regulations, specifically the RAS (Technical Regulation of the Drinking Water and Basic Sanitation Sector) from the Colombian government, which sets water demand for buildings intended for academic activities with established allocations of 20 to 25 L per student per school day [25]. Here, it can be estimated that 60% (≈16 L) is for consumption, and 40% (≈9 L) is for sanitary use.

Similarly, being a coastal community, the available resource for desalination will be considered as seawater; the parameters are presented in

Table 1. Physicochemical parameters of seawater.

Parameter	Value	Unit
Ph	8.1	pH
Calcium (Ca)	420	mg/L
Magnesium (Mg)	1368	mg/L
Sodium (Na)	12,190	mg/L
Potassium (K)	391	mg/L
Ammonium (NH4)	0.2	mg/L
Barium (Ba)	0	mg/L
Strontium (Sr)	0	mg/L
Bicarbonates (HCO3)	189	mg/L
Sulphates (SO4)	2786	mg/L
Chlorides (Cl)	20,845.4	mg/L
Fluoride (F)	0	mg/L
Phosphates (POP4)	0	mg/L
Nitrites (NO3)	0	mg/L
Boron (B)	0	mg/L
Silicon Oxide (SiO2)	0	mg/L

.

4.1.2. Energy Potential

In a general context, thanks to Colombia’s climatic conditions, its location in the tropics, and the Andes mountain range, the country possesses a high potential for the development of renewable energies (RE) in various regions. This potential is primarily harnessed for wind, solar, biomass, geothermal, and small hydroelectric power generation. However, it must create the necessary conditions to foster its development to establish itself as a leading nation in reducing its carbon footprint, with the capacity to export clean energy [26].

In Colombia, the potential of photovoltaic energy is calculated based on information provided by meteorological stations installed by IDEAM. UPME has published the Solar Radiation Atlas in Colombia, which relies on solar radiation and radiometric stations, illustrating the solar potential for each Colombian region. The results are available in

Table 2. Solar energy potential in Colombia (adapted from [27]).

Region	kWh/m2/Year
Guajira	2.190
Costa Atlántica	1.825
Orinoquía	1.643
Amazonía	1.551
Andina	1.643
Costa Pacífica	1.278

.

The most recent analysis of Colombia’s wind potential was conducted in 2006 through the Wind and Wind Energy Atlas of Colombia, developed by UMPE and IDEAM. The analysis utilised data from 111 stations across the country, along with meteorological models.

Table 3. Wind energy potential in Colombia (adapted from [27]).

Location	W/m2
Guajira	1000–1331
Communities around Barranquilla	216–512
Coast Region of Urabá	125–216
Paso de la línea between Ibagué y Armenia	216–343
Rest of Colombia	Less than 125

indicates that regions such as La Guajira and areas near Barranquilla exhibit a high potential for mean multiannual power density at 20 m in height, suggesting these areas could be highly suitable for wind energy generation in Colombia.

The choice of solar energy as the primary renewable source for powering the desalination system was based on a comparative evaluation of the region’s renewable energy potentials. Manaure, La Guajira, exhibits one of the highest levels of solar irradiance in Colombia, averaging 2190 kWh/m²/year according to the Solar Radiation Atlas [27]. In contrast, while the region also has substantial wind energy potential, with mean power densities ranging from 1000 to 1331 W/m² [27], the implementation of wind turbines in remote and resource-constrained settings like Manaure poses significant logistical and economic challenges.

Solar energy was selected due to its lower maintenance requirements, greater ease of installation, and alignment with existing infrastructure at the study site, such as available rooftops for photovoltaic panel installation. Moreover, advancements in photovoltaic technology, including increased efficiency and cost reductions, make solar power a cost-effective and reliable option for addressing water scarcity in remote communities.

This decision aligns with the study’s objective to propose a feasible and replicable solution for coastal communities, where solar energy represents a more accessible and sustainable option compared to wind or hybrid systems.

The need to reduce reliance on traditional and costly energy sources has led to the evaluation of renewable energy sources that can be implemented. This transition has been gradual with the aim of ensuring a sustainable future for technology [28], ushering in the use of energies such as solar, wind, hydroelectric, biomass, geothermal, and hybrid systems. These have been recognised as sustainable energy sources for this process [29].

These alternative renewable energies are considered cost-effective. However, their implementation presents shortcomings. In the case of solar energy, the disadvantage lies in low energy efficiency [13], due to the lack of optimisation in energy capture and storage. Nevertheless, it remains a promising alternative, given its numerous benefits and advancements, particularly in terms of the increased lifespan of these elements. This has generated research interest and economic investment [29]. It is worth noting that one of the challenges facing this system is its direct relationship with climatic conditions and the availability of solar radiation in the applied area. This condition makes it inapplicable in all areas, which is considered a weakness of this type of energy [29].

For the specific focus of this research, the community of La Paz possesses sufficient energy potential, assessed using the HOMER Pro software. This evaluation incorporated databases from NASA and predictive models employed for energy projection, as illustrated in Figure 3.

4.1.3. Legal Framework for Water Measurement and Quality

During the information gathering process, several decrees and regulations governing water measurement and quality in Colombia were identified, and they are applicable to the target community of this study. These norms establish standards and essential parameters to ensure the potability of water and control pollutant emissions. The following are the key decrees found:

Resolution 2115 of 2007—IRCA (Índice de Riesgo de Calidad del Agua)

Through this resolution, characteristics, basic instruments, and frequencies are established for the control and surveillance system for the quality of water for human consumption.

This resolution outlines the methodology by which the results of water sample analyses for consumption are evaluated through a risk scoring system assigned to each chemical element present in the water.

Resolution 2254 of 2017—NMCP (Niveles Máximos Contaminantes Permisible)

Establishes the ambient air quality standard through maximum permissible pollutant levels. These levels serve as regulatory limits for various substances that could affect air quality. The regulations aim to ensure that pollutant emissions remain within safe limits, thus protecting public health and the environment.

RAS (Reglamento Técnico del Sector de Agua Potable y Saneamiento Básico)

RAS plays a crucial role in the sector by establishing technical standards for the calculation of gross and net water demands. These standards are essential to ensure the efficient and sustainable use of water resources, considering both population needs and environmental aspects.

These legal frameworks provide the basis for the continuous assessment and monitoring of water quality in Manaure, ensuring that communities have access to safe drinking water and that measures are implemented to mitigate environmental impacts associated with desalination and other water supply-related processes in the region. Knowledge and compliance with these laws are fundamental for the successful design and implementation of solar-powered desalination projects in coastal communities like Manaure.

4.2. Application of the Simulation Model

4.2.1. Input Data

Based on the data previously collected regarding the seawater quality in the Guajira area and the calculated demand for potable water for at least 500 children from the La Paz community in Manaure, following RAS regulations, a simulation was conducted using IMSDesign software with the input parameters depicted in Figure 4, at a temperature of 27.5 °C and a pH of 8.1.

Following this, the design parameters for the entire reverse osmosis system were then entered, as illustrated in Figure 5. The demand of 8 m³/day was estimated based on the Colombian government’s Technical Regulation for the Drinking Water and Basic Sanitation Sector (RAS), which assigns an allocation of 25 L per student per school day. For a population of 500 students, this gives a total demand of 12,500 L/day, of which 60% (≈7500 L) is for direct consumption. With a 5% adjustment, this gives a demand of 8000 L/day (equivalent to 8 m³/day). This value was used to maintain a permeate flow rate. The detailed specifications of the SWC5-LD-4040 membrane, including dimensions and specific features utilised for reverse osmosis, are provided in Supplementary Information Figure S1.

4.2.2. Desalination Plant Simulation by RO

The simulation was conducted using Hydranautics’ IMSDesign software, resulting in the outcomes depicted in Figure 6. The detailed flow diagram of the desalination plant, showcasing the processes, pressures, pH, TDS, and other key parameters across each stage, is provided in Supplementary Information Figure S2.

As a result of this simulation, the electrical consumption required by the plant for a pumping power equivalent to 5.91 kWh/m³ is obtained.

4.2.3. Simulation of the Electrical Supply System

With a pumping power value of 5.91 kWh/m³ for the plant, the desired photovoltaic system must meet a load of 47.28 kWh/day to produce 8 m³/day of potable water. This value was calculated based on the required pumping power for the desalination process. The software HOMER Pro was used to simulate and design the system, where the plant’s location was input to access local energy potential data. The simulation also considered equipment specifications, load characteristics, and techno-economic factors.

The pumping power requirement of 5.91 kWh/m³ calculated for the proposed desalination system aligns with the range reported in similar renewable energy-powered desalination systems. For instance, [19] reported energy consumption values between 3.5 and 6.5 kWh/m³ for reverse osmosis desalination plants powered by hybrid solar and wind systems. Similarly, [5] highlighted that standalone solar-powered systems typically achieve energy demands in the range of 4 to 6 kWh/m³, depending on the specific design and operational parameters.

While the value of 5.91 kWh/m³ is on the higher end of this range, it is important to note that the design prioritises robustness and reliability to meet the demands of a remote coastal community. Further optimisation could reduce this value, such as by incorporating pre-treatment technologies to minimise membrane fouling or by employing high-efficiency pumps. These improvements could bring the energy consumption closer to the lower end of the reported range, enhancing the overall efficiency of the system.

In the baseline scenario, the desalination plant would be directly powered by the grid. However, the goal is to reduce the levelised cost of energy (LCoE) by incorporating a solar photovoltaic system. The HOMER Pro software further adjusts the energy demand, generating a peak value of 55 kWh/day to ensure that the system can accommodate fluctuations in energy usage. The schematic of the photovoltaic system, as shown in Figure 7, was derived from this simulation.

The components to be used in this case are the equipment currently available at the La Paz Rural Ethnoeducational Institution (see

Table 4. Component specifications.

Component	Name	Nominal Power	Unit
Panel	AS-6P30	0.28	kW
Converter	PV18-3048 LHM	3	kW
Grid	Grid	999,999	kW
Dispatch strategy	HOMER Cycle Charging

), with the objective of evaluating the case for extending the photovoltaic capacity of the current system for a solution of this type.

In a 10-year time horizon established in the simulation of the PV system for the desalination plant, the optimal energy system (represented by the blue line) was obtained as a result compared to the base case (grey line), which corresponds to a system where the plant is connected only to the public power grid. Figure 8 shows the cumulative nominal cash flow ($) on the Y-axis and the years of project life on the X-axis.

In addition, Figure 8 presents the techno-economic values for both cases, including NPC (net present cost), initial capital, operation and maintenance (O&M) costs, and LCOE (levelised cost of energy), as well as IRR (internal rate of return), ROI (return on investment), and Simple Payback. These indicators allow comparing the profitability and economic viability of the optimal option against the base case. The PV system (blue line) has a higher profitability, which is reflected in its higher indicators compared to the base case.

A promising solution was obtained, projecting very short payback times, and indeed a renewable alternative in combination with the grid was the most cost-effective option for this type of system.

4.2.4. Algorithm for Comprehensive Analysis of Environmental and Human Health Impacts

The development of this algorithm plays an important role within the simulation model, as it integrates the physicochemical results of the desalination plant and the technical aspects of the electrical supply system to conduct a comprehensive analysis of potential environmental and human health impacts.

Initially, the algorithm analyses the physicochemical results of the water entering and exiting the plant and compares them with the optimal conditions for drinking water provided by Colombian regulations. In Figure 9, the parameters of the incoming and outgoing water, as well as their composition, can be observed. Based on the values exceeding the optimal conditions, a risk assessment of water quality is conducted using the IRCA. This calculation under tolerance levels of 10% will determine whether, according to Colombian regulations, the desalinated water is completely safe for human consumption.

Diseases transmitted through water are a public health problem affecting communities that lack adequate water treatment and management (IRCA). Therefore, for those values exceeding the optimal conditions for drinking water for human consumption, the algorithm, which already has information on potential diseases from the National Water Quality Report for Human Consumption of 2021, correlates the exceeded values and provides the potential adverse health effects, as shown in the table in Figure 10.

On the other hand, the environmental impact in this case, by integrating renewable energy systems, entails a certain amount of emissions generated. Therefore, the algorithm displays the best combination of electrical supply based on the energy availability provided by the second software (Homer PRO), as depicted in Figure 11.

Along these lines, with this combination, the installed capacity of renewable energy is higher. Therefore, the algorithm sums the amount of emissions generated by both the grid and the renewable part, giving a total of emissions which is detailed in Supplementary Information Figure S3, to have a global understanding of the system in question.

5. Discussion

This research achieved advancements in the comprehensive design of a desalination system powered by solar energy for the coastal community of La Paz in Manaure, La Guajira, Colombia. The simulation model results provide a detailed overview of the technical, economic, and environmental assessment of the proposed solution.

The community of La Paz faces critical challenges in the supply of potable water. The solar desalination model aims to address this issue, particularly focusing on the Institución Etnoeducativa Rural La Paz, where over 600 children face inhumane conditions and receive limited amounts of water. The simulation reflects the capacity of the proposed system to sustainably meet the community’s demand for potable water.

Technical challenges were identified, such as the high energy cost of desalination processes and the need to integrate renewable sources. The proposed solution includes the use of solar energy to power the desalination process, thereby addressing the dependence on fossil fuels. The model results indicate that the combination of renewable technologies can be effective, but careful design and continuous optimisation are required.

The economic viability is appreciated in terms of the long-term benefits for the educational institution. Although the initial investment may be significant, the results indicate that water autonomy and long-term cost reduction justify the implementation of the solar desalination system.

The environmental impact analysis reveals that the integration of renewable energies reduces emissions, making it more sustainable than traditional sources. The algorithm for analysing the impact on human health evaluates the quality of desalinated water and its relationship with potential adverse health effects, highlighting the importance of complying with Colombian regulations to ensure water safety for human consumption.

The results reveal a direct correlation between the quality of desalinated water and energy consumption, highlighting the importance of a comprehensive approach to addressing water scarcity and energy needs in coastal communities. In this context, potential health adversities caused by low water quality indices are inversely related to the amount of energy available for the operation of the plant. Therefore, the calculation of the IRCA plays a fundamental role in the water potability analysis.

The integration of tools such as IMSDesign, HOMER PRO, and MATLAB has been essential for understanding the system as a whole. These tools provide a more comprehensive and accurate insight into the technical, economic, and environmental aspects, enabling informed decision making and effective planning for the implementation of the solar-powered desalination system.

The proposed simulation model is designed with flexibility to allow adaptation to other coastal communities worldwide. Key parameters that could vary significantly between locations include water quality characteristics (e.g., salinity, pH, and contaminant levels), renewable energy potential (e.g., solar irradiance or wind power availability), and local regulatory frameworks governing water quality and environmental impact. Adjustments to these parameters would be essential to ensure the model’s applicability and efficiency in different contexts.

For instance, communities with higher salinity levels may require membranes with enhanced durability and pre-treatment systems, while those with lower solar irradiance might benefit from hybrid renewable energy systems, such as combining solar with wind power. Despite these potential variations, the integrated methodology presented—utilising HOMER Pro, IMSdesign, and MATLAB—provides a robust framework that can be tailored to diverse geographical and socio-economic conditions.

This adaptability ensures that the model serves as a replicable solution for addressing water scarcity in remote coastal communities, fostering sustainability and resilience in varying global contexts.

6. Conclusions

The results obtained from the comprehensive simulation demonstrate that the incorporation of solar energy into the desalination process can be effective and sustainable. The designed model encompasses technical, economic, and environmental aspects, providing a comprehensive solution to improve access to clean water in coastal communities. The combination of solar-powered desalination and renewable energy generation offers a positive response to the research question.

The simulation model proposes a solution with the potential to positively impact the community of La Paz by significantly improving their access to clean and safe water. The water autonomy provided by the solar-powered desalination plant would reduce dependence on costly external sources, benefiting the Institución Etnoeducativa Rural La Paz and its more than 600 children. This advancement would contribute not only to the community’s health but also to its social and educational development.

It is important to acknowledge that the research may have certain areas for improvement. For future investigations or projects, a deeper examination of brine treatment, economic factors related to remote or hard-to-access areas, and the assessment of post-treatment processes that could enhance the efficiency of the entire solution are recommended. Additionally, community involvement in project planning and execution can also strengthen sustainability and local acceptance.