Design of a Hybrid Wind and Micro-Hydro System for Sustainable Water Treatment

Abstract

Newfoundland and Labrador have strong wind and water resources, making hybrid renewable energy systems an important option for the region. This paper presents the design and simulation of a system that combines wind turbines and micro-hydro power to deliver clean electricity for water treatment in remote communities. Many isolated areas still rely on diesel and other conventional sources, which create environmental concerns. Using HOMER Pro 3.17.1 software, the system was modeled based on local climate and resource conditions. Results show that it can produce over 35,000 kWh per year, enough to power a standard water treatment unit serving more than 240 people. By integrating wind and hydro with battery storage, the system ensures stable operation and reduces dependence on fossil fuels. The environmental analysis confirms that it avoids over 9 tons of CO₂ emissions annually. The novelty of this work is its site-specific approach, showing how renewable energy can improve both energy security and water quality in remote Canadian communities while providing a model for sustainable rural development.

1. Literature Review

Wang et al. (2022) [1] propose a hybrid renewable energy system combining wind, photovoltaic (PV) solar, and energy storage to power drinking water treatment plants (DWTPs). The water treatment process is energy-intensive, leading to high costs and carbon emissions. The authors present a multi-objective optimization model to design and operate this hybrid system, addressing technical, economic, social, and environmental factors. The model, solved using LINGO 18.0 software, aims to determine the optimal system configuration and self-sufficiency ratio. The case study in China shows that the proposed hybrid system achieves a 95% self-sufficiency ratio. The system significantly reduces energy costs and emissions, offering a sustainable solution for water treatment. The study also evaluates the impact of electricity pricing and natural resource changes on the system’s performance. This research provided valuable insights for planners and investors, offering a comprehensive approach to integrating renewable energy into industrial processes and suggesting how the model can be applied in different regions.

Allouhi (2024) [2] design a hybrid renewable energy system (HRES) combining solar PV, wind turbines, battery storage, and a run-of-river micro-hydropower plant for Ouenskra, a rural area in Morocco. The system aims to provide clean electricity and support hydrogen fuel cell bikes for green transportation. The total daily load requirement is 400 kWh, with solar providing 60% of the electricity and micro-hydropower 40%. The system also generates 0.2 kg/h of hydrogen for 69 bike charging sessions daily [2]. The study finds that higher solar energy potential reduces costs, while wind variability has minimal impact. The optimized HRES shows a Net Present Cost (NPC) of $473.6k and a Cost of Electricity (COE) of $0.147/kWh, offering a cost-effective solution to rural electrification and sustainable transportation. This approach aligns with Morocco’s sustainable development goals, combining renewable energy and hydrogen to promote eco-friendly energy use in rural communities.

He et al. (2022) [3] analyze the optimal hybrid renewable energy system for Huraa Island in the Maldives, focusing on combinations of diesel power, solar photovoltaic (PV), wind power, and battery storage. The study evaluates the impact of different configurations on renewable penetration (RP) and levelized cost of electricity (LCOE). The results show that a high-rated PV system is optimal due to its high RP and low LCOE. Wind power is also beneficial, with a 1000 kW wind turbine being the ideal solution. Battery storage of 4000 kWh is recommended, but not necessary when RP is below 53%. The research explores multiple configurations, including diesel-PV, diesel-wind, and diesel-PV-battery systems, to ensure reliable power while minimizing costs and emissions.

Sahay (2022) [4] focuses on designing and analyzing a micro-hydro turbine system for small-scale electricity generation from low-head water sources. The system uses water stored in an overhead tank at 11.25 m to harness potential energy, converting it into kinetic energy as it flows through a nozzle, striking the blades of a Pelton wheel turbine. The rotating turbine drives a DC generator, producing electricity, which is then stored in batteries for domestic use. The system’s design includes essential components like a water storage tank, penstock, turbine, generator, and battery storage. Calculations suggest that the system can generate up to 0.047 kW under optimal conditions. The study emphasizes the importance of head height and water discharge for determining energy output, showing a strong correlation between these variables and generated power. This micro-hydro system offers an effective solution for reducing electricity bills and promotes sustainable energy practices, aligning with global renewable energy goals.

Kefif et al. (2022) [5] design a micro-hydro-wind hybrid system for electricity supply in Yesser valley, Algeria, aiming to reduce costs and provide reliable energy using renewable sources. Using Homer Pro software, they model the system’s performance across three valley areas with different water flow rates (10, 19, and 24.6 m³/s) and wind speeds. The results show that the system can meet the load demand in all areas, with wind power needed only in the estuary during summer. The system’s cost decreases with higher wind speeds and flow rates, with the most cost-effective setup in the source area. The study highlights the system’s environmental benefits, efficiency, and sustainability.

Icaza and Borge-Diez (2021) [6] present a technical and economic analysis of a hybrid renewable energy system for a set of airplane-shaped buildings in Cuenca, Ecuador. The system consists of solar photovoltaic (PV) panels, wind turbines, hydrokinetic turbines, and battery storage, aiming to meet the electricity demand while promoting sustainable development in the surrounding area. Using HOMER Pro software, the system’s performance was optimized to cover the buildings’ annual energy requirement of 234.86 MWh/year. The study finds that while the combination of these renewable sources has a higher upfront cost, it ensures a more reliable energy supply, maintaining battery charge levels above 40%. Over a 25-year period, the system achieves a Net Present Cost (NPC) of $37,600 and a Cost of Electricity (COE) of $0.386/kWh. The methodology and design proposed can be adapted to similar locations globally, offering an innovative solution for energy supply in unique building complexes.

Ali and Jang (2021) [7] investigate the optimal design of a hybrid renewable energy system (HRES) to supply sustainable electricity to Deokjeok-do Island in South Korea, a remote location without conventional grid access. The proposed system combines wind and solar energy as primary sources and incorporates two energy storage solutions—battery storage and pumped hydro storage (PHS)—to address energy surplus and shortages. Using a full year of real electricity consumption data and performing 8760 simulations, the researchers analyzed the system’s technical and economic performance. The average daily load was found to be 24,720 kWh, with a peak demand of 2291.54 kW. The study evaluated four HRES configurations based on their Levelized Cost of Energy (LCOE) and Net Present Cost (NPC), also incorporating a detailed component-wise economic analysis and sensitivity assessment. The results demonstrate the feasibility and effectiveness of hybrid renewable systems for remote island electrification while contributing to greenhouse gas reduction.

Patil et al. [8] investigated a hybrid energy system combining Floating Solar Photovoltaics (FPV) and hydropower using HOMER Pro simulation. Their study demonstrates that this configuration enhances energy reliability, reduces water evaporation, and lowers the Levelized Cost of Energy (LCOE) from 6.40 Rs/kWh (FPV only) to 4.15 Rs/kWh in the hybrid setup, achieving zero grid dependency.

2. Water Treatment System

The load consumption in this project is about the water treatment device.

This device must be selected and designed in accordance with the requirements outlined in the Canadian government’s guidelines.

According to these guidelines, if your water source is independent, such as a: well, lake, river, drinking water is required to be tested regularly.

Local public health authorities can advise you on which contaminants (microbial or chemical) should be tested. If your drinking water does not meet the Canadian Drinking Water Quality Guidelines, appropriate corrective actions must be taken, including: installing point-of-use treatment devices or point-of-entry treatment systems.

Based on these same guidelines, any treatment device selected must comply with at least one of the following recognized performance standards and be properly certified. These standards are [9]:

• NSF/ANSI Standard 42: Drinking Water Treatment Units—Aesthetic Effects
• NSF/ANSI Standard 44: Cation Exchange Water Softeners
• NSF/ANSI Standard 53: Drinking Water Treatment Units—Health Effects
• NSF/ANSI Standard 55: Ultraviolet Microbiological Water Treatment Systems
• NSF/ANSI Standard 58: Reverse Osmosis Drinking Water Treatment Systems
• NSF/ANSI Standard 62: Drinking Water Distillation Systems

The drinking water treatment system comprises Reverse Osmosis (RO) System, Ultra filtration (UF) System, EDI Ultrapure System, Water Reuse System, and Brackish Water Desalination, which together form a multi-stage process to transform raw water into clean and safe drinking water. First, the water passes through a Quartz Sand Filter, where large suspended particles are removed. It then flows through an Activated Carbon Filter, which eliminates chlorine, organic compounds, and undesirable taste and odor. In the next stage, a Water Softener reduces calcium and magnesium ions, preventing scaling on RO membranes. The water is subsequently pressurized by a High-Pressure Pump and enters the Reverse Osmosis (RO) unit, where more than 95% of dissolved salts and impurities are removed. To ensure microbial safety, the treated water is disinfected with Ultraviolet (UV) radiation, followed by a final disinfection step using an Ozone Generator for additional microbial control and water quality stabilization. The final output is water with an electrical conductivity of less than 10 μS/cm, total organic carbon below 0.5 mg/L, and a microbial count of fewer than 100 cfu/mL, making it crystal clear, microbiologically safe, and of high quality for drinking [10].

The energy consumption of a standard water treatment unit with a capacity of 3000 L/h is estimated at 5.6 kWh [10]. According to official data from the Government of Canada (2021), the average daily water use per person is 223 L [11]. Considering possible downtime for maintenance, servicing, and weather-related interruptions, this system can reliably meet the daily demand of approximately 242 people. This device was selected because of its relatively low power requirement, which makes it feasible to supply energy through a hybrid wind–hydro system.

3. Project Location

The project will be take place out in the Camp Pond Brook area which is located downstream of Camp Pond Figure 1, in the province of Newfoundland and Labrador, Canada. This site is in the Labrador region, known for its clean freshwater resources and natural landscapes. While the area is not densely populated, its hydrological characteristics make it suitable for assessing the potential of small-scale hydropower systems. The main goal of the project is to explore whether the natural water flow in this area can be used as a clean, local and renewable source of energy to supply electricity for nearby communities.

4. Data Collection

4.1. Hydro

To obtain one-year hourly flow rate data, reference [13] was used. According to this source, the average annual river flow rate is 0.185 ${\mathrm{m}}^3$/s. Detailed information about the corresponding hydrometric station is provided in

Table 1. Station information.

Station	Active	Province/Territory	NL
Latitude:	56°20′26″ N	Longitude:	62°2060′37″ W
Gross drainage area:	$24.3 \mathrm{k}{\mathrm{m}}^2$	Effective drainage area:	N/A
Record length:	28 Years	Period of record:	1995–1999–2003–2025
Regulation type:	Natural	Regulation length:	N/A
Real-time data available:	Yes	Sediment data available:	No
Type of water body:	River	Operation Period:	JAN–DEC
Publishing office:	DARTMOUTH	Current Operation:	Continuous

. These flow data serve as the basis for estimating the potential for electricity generation using a micro- hydropower system. By combining this flow rate with the site’s topographic characteristics and available head, the potential power output of the micro-hydro system can be calculated. This information is critical for preliminary design, selecting appropriate turbines, and assessing the project’s economic feasibility.

The daily discharge rate for 2023 at the selected hydrometric station is presented in Figure 2 [13]. The figure provides an overview of flow variations throughout the year, showing both seasonal patterns and peak discharge events. These variations are important for evaluating the feasibility and reliability of micro-hydropower generation. Understanding daily flow trends supports more accurate sizing of system components and helps maintain a continuous power supply, particularly in regions with strong seasonal changes in river flow. The elevation of the hydrometric station, obtained from reference [14], was measured at 4 m. This information is essential for calculating the net head, which is a key parameter in the design of micro-hydropower systems. Accurate assessment of site elevation directly influences the estimation of power output and the selection of suitable components, such as turbines and generators.

Water flow energy, or hydraulic energy, is a form of renewable energy derived from the natural movement of water in rivers or surface streams. This energy consists mainly of two components:

• Potential energy, related to the elevation difference (head)
• Kinetic energy, related to the velocity of the water flow

In micro-hydropower systems, the potential energy is primarily harnessed to generate electricity. The extractable energy can be estimated using the following formula [15]:

$$\mathrm{P} = \mathsf{\rho } \times \mathrm{g} \times \mathrm{Q} \times \mathrm{H}$$

(1)

where:

P: Power output (watts)

ρ: Water density (approx. 1000 kg/m³)

g: Gravitational acceleration (9.81 m/s²)

Q: Flow rate (m³/s)

H: Net head (m)

P = 1000 × 9.81 × 0.185 × 4 = 7.2 KW

The estimated available power of 7.2 KW from the water flow in this area demonstrates the significant potential and favorable conditions for electricity generation using micro-hydropower turbines. This amount of power is well-suited for meeting the energy demands of small communities, research stations, or off-grid projects. Moreover, it highlights the opportunity to reduce dependence on fossil fuels and promote the adoption of clean, renewable energy sources.

4.2. Wind

According to NASA’s POWER database, the average wind speed in the study area is 7.42 m/s, as shown in Figure 3 [16]. This is higher than the average wind speed in St. John’s, which is about 6.6 m/s. The difference shows that the study area has stronger wind resources and better potential for wind energy use. These favorable wind conditions make the site suitable for developing efficient and cost-effective wind power systems. They also support the wider goal of reducing reliance on fossil fuels and promoting clean, sustainable energy.

In wind systems, the potential energy is primarily harnessed to generate electricity. The extractable energy can be estimated using the following formula [17]:

For example:

$$\begin{array}{c}\mathrm{A} = 9.62 {\mathrm{m}}^3\\ \rho =1.293 \mathrm{Kg}/{\mathrm{m}}^3\\ \mathrm{V}=7.42 \mathrm{m}/\mathrm{s}\end{array}$$

$$\mathrm{P} = 0.5 \times \mathsf{\rho } \times \mathrm{A} \times {\mathrm{V}}^3 = 2540 \mathrm{W} \cong 2.5 \mathrm{KW}$$

(2)

For a wind turbine with a 9.62 m² swept area and under average wind speed conditions of 7.42 m/s, we can expect to extract about 2.5 KW of electrical power. This demonstrates the potential capacity of the wind system to generate electricity under the specified conditions. Thus, for a sample area of this size, the turbine would generate roughly 2.5 KW of power.

5. Hydro Turbine Selection

Considering the designed effective head at the project site, along with the analysis of the average and maximum available flow rates, the selection of a suitable hydropower turbine is carried out to ensure optimal performance while minimizing construction and installation costs. In this context, the decision-making process is guided by the “Head-Flow Ranges of Small Hydro Turbines” diagram presented in Reference [18], through which various turbine options are evaluated both technically and economically to identify the most appropriate choice based on the site’s hydraulic.

$$Q_{\mathrm{Average} \mathrm{Flow} \mathrm{rate}} = 0.185 {\mathrm{m}}^3/\mathrm{s}$$

$$Q_{Max Flow rate} = 1.27 {\mathrm{m}}^3/\mathrm{s}$$

$$\mathrm{H} (\mathrm{Net} \mathrm{head}) = 4\mathrm{m}$$

Based on the diagram presented in Figure 4, and considering the available head and flow rate at the project site, Propeller and Kaplan turbines are identified as suitable options for the given hydraulic conditions. Both turbine types perform efficiently in low to medium head and flow scenarios. However, due to the simpler mechanical structure, lower initial cost, and reduced maintenance requirements of the Propeller turbine compared to the Kaplan turbine, the Propeller turbine is deemed more economically and operationally feasible for this project. Therefore, the Propeller turbine has been selected as the final choice. Figure 5 shows the placement of the propeller turbine under low-head conditions.

6. Simulation Design in Homer

The size and economics of the system were modeled using the HOMER Pro 3.17.1simulation software [19]. The system depicted in the Figure 6 includes the following components:

• Hydro Turbine
• Wind Turbine
• Battery
• Convertor
• Load (standard water treatment device)

Figure 3 shows the monthly average wind speed data, which was used as input to the HOMER Pro software. This information is important because it helps us understand how much wind energy can be expected at the site and how it will affect the system’s performance and long-term costs. As seen in the chart, wind speeds are generally higher in the winter months—peaking in December—and lower in the summer, especially in July. These seasonal variations remind us that the time of year plays a big role when planning to integrate wind energy. To make the analysis more reliable, we used over 30 years of historical wind data from NASA’s POWER database. This gives us confidence in our results and supports better decisions for turbine selection, energy forecasting, and overall system densign. In addition, the wind turbine performance is modeled using its power curve, as illustrated in Figure 7. The power curve is essential because it shows how much electricity the turbine can generate at different wind speeds. For example, at very low wind speeds the turbine produces little or no power, while at medium speeds it generates more efficiently, and at very high speeds it shuts down for safety. The wind speed data from Figure 3 and the turbine’s power curve from Figure 7 are used as inputs to HOMER. This allows the software to accurately estimate how much electricity the wind turbine will produce throughout the year. The hub height of the wind turbine was set to 12 m in the simulation.

The average stream flow data shown in Figure 2, based on measurements from the Nain river station, is used as input for the HOMER software. This information is essential for evaluating the availability of hydro resources throughout the year and for designing the hydro component of the hybrid energy system effectively. The chart shows a noticeable increase in river flow during late spring, particularly in May, likely due to seasonal runoff or melting snow, followed by a gradual decrease in the following months. Understanding these seasonal changes is crucial not only for estimating potential hydropower generation but also for planning how the hydro component will work together with other energy sources, such as wind or solar. By identifying periods of high and low water availability, system designers can make informed decisions about storage needs and overall system balance, ensuring a reliable and continuous energy supply throughout the year.

Figure 8 illustrates the electric load pattern of a typical water treatment system, as modeled using HOMER Pro. This load profile represents the energy required to support core operations such as water purification and distribution. The daily load curve shows a clear increase in electricity consumption during daytime hours, reflecting the system’s active operational period. Seasonal data indicate relatively steady energy demand throughout the year, highlighting the consistent operation of the system. Accurately understanding this load behavior is essential for designing a hybrid energy system that can reliably and efficiently meet the operational needs of the water treatment process year-roand.

Figure 9 presents the wind power output profile for the entire year, based on results generated by the HOMER Pro simulation. The chart visualizes hourly variations in wind energy production across all 365 days, highlighting the dynamic nature of wind resources at the site. According to the simulation, two wind turbines—each rated at 3.3 kW—are proposed to meet the energy demands of the water treatment system. Combined, they offer a total rated capacity of 6.6 kW. Over the year, these turbines are expected to produce roughly 18,982 kWh/year of energy, with the highest instantaneous output reaching 8.98 kW and the lowest dropping to zero during calm periods. On average, they deliver around 2.17 kW and are projected to operate for about 7010 h annually. In this figure lighter bands signal higher output and darker areas indicate lower or no generation. This detailed view helps assess how consistently the wind system can contribute to the hybrid setup and ensures better planning for energy storage and load management.

Based on the available stream flow rate and the hydraulic head, the HOMER Pro software recommended the use of a 10 kW hydro turbine. According to the simulation results, the actual performance of the turbine is as follows: total annual energy production of 16,431 kWh/year, nominal capacity of 2.2 kW, average power output of 1.88 kW, maximum output of 2.8 kW, and minimum output of 0 kW. The turbine is expected to operate for approximately 7272 h per year. In Figure 10 lighter bands signal higher output and darker areas indicate lower or no generation.

Figure 11 presents the monthly energy output generated individually by the two wind turbines (AWS 3.3 kW) and the hydro turbine (Hyd10), as modeled using HOMER Pro. This water treatment requires 23 kWh/day and has a peak of 2.439 kW. In the proposed system, the following generation sources serve the electrical load. Together, these renewable sources supply a total of approximately 35,413 kWh per year. The chart clearly shows how energy production fluctuates across the months, with the hydro turbine contributing more significantly during spring—particularly from April to June—likely due to seasonal increases in stream flow. The wind turbines, on the other hand, maintain a fairly consistent output throughout the year, offering dependable support during months when hydro generation is lower. This seasonal variation highlights the importance of combining multiple renewable sources, as it helps ensure steady and reliable energy production throughout the year.

The extra energy produced by the wind and hydro turbines is stored in a battery bank consisting of 28 batteries, each rated at 100 Ah [20]. The DC bus voltage is 48 V, achieved by configuring the batteries into seven strings of four 12 V batteries connected in series. This configuration allows for effective energy storage. Figure 12 displays the state of charge (SOC) of the battery bank over time. In the proposed system, battery storage, offering a nominal storage capacity of 22.5 kWh. Throughout the year, the battery handles an estimated 672 kWh of energy throughput, reflecting its active role in daily energy balancing and backup support. According to simulation results, the system experiences annual energy losses of approximately 109 kWh, mainly due to typical charge/discharge inefficiencies and self-discharge effects. Overall, the battery plays a critical role in enhancing the stability and reliability of the hybrid energy system, especially during periods of reduced renewable generation or increased load demand. In this figure, lighter regions correspond to periods when the battery maintains a high state of charge, whereas darker areas reflect lower charge levels or full discharge. As shown, the battery system helps compensate for the drop in hydro turbine output during the last months of the year, as well as in the second and third months of the year. During these periods, when hydro generation is low, the system relies more on the stored energy in the batteries to meet the demand.

Figure 13 presents a schematic layout of the hybrid energy system, highlighting the interconnections between the wind turbine, hydro turbine, drinking water treatment facility, and the battery storage unit. In this setup, both the wind and hydro generators feed power into a shared AC bus, which is then converted to DC using an AC/DC power converter. This converter ensures the smooth delivery of power by aligning voltage and current levels for downstream components. The electricity is supplied to the water treatment unit, supporting its purification and distribution processes, while any excess energy is stored in the battery bank. This configuration not only ensures a steady and efficient energy flow but also improves the system’s overall reliability by allowing the use of stored energy during periods of low renewable generation. Additionally, integrating multiple renewable sources helps maintain balance and stability, reducing the system’s vulnerability to seasonal or resource-specific fluctuations.

7. Environmental Assessment

The environmental benefits of the proposed hybrid renewable system were assessed through detailed simulations using the HOMER Pro. The software calculated the amount of pollutants that would have been released if the same annual electricity demand had been supplied entirely by a conventional diesel-based generation system.

As summarized in

Table 2. Annual Pollutant Emissions Prevented by the Proposed System.

Pollutant	Avoided Emissions (kg/yr)
CO2 (Carbon dioxide)	9319
CO (Carbon monoxide)	70.5
Unburned Hydrocarbons	2.57
Particular Matter	4.27
Sulfur Dioxide	22.9
Nitrogen Oxides	80.1

, the results indicate that more than 9 tons of CO₂ per year would have been emitted, together with other harmful pollutants such as CO, unburned hydrocarbons, particulate matter, SO₂, and NO_x. By replacing fossil fuel–based electricity with renewable resources, the system effectively avoids these emissions. This not only reduces greenhouse gas contributions to climate change but also lessens local air pollutants that directly affect community health and air quality.

8. Conclusions

This study designed and simulated a hybrid renewable energy system combining wind and micro-hydro power for the remote Camp Pond Brook area in Newfoundland and Labrador. The system provides reliable electricity for water treatment and makes good use of local wind and water resources. Simulation results from HOMER Pro show the system is technically and economically feasible. The total annual energy production is 35,413 kWh, with 16,431 kWh from hydro and 18,982 kWh from wind. This fully covers the needs of a water treatment unit serving over 240 people. Batteries ensure continuous power even when renewable sources vary. The system also brings clear environmental benefits. Replacing diesel generators avoids over 9 tons of CO₂ emissions each year and reduces other pollutants, helping fight climate change and improve air quality. Overall, the study provides a practical, site-specific solution for clean energy and safe drinking water in remote communities. It offers a model that can be replicated elsewhere. Future work could add other renewable sources, like solar PV, to make the system even more resilient and applicable to similar regions.