Solar Water Pumping System Designed with HOMER and LORENTZ for Kufri, Khushab, Pakistan

This research paper presents a design and optimization of a solar-powered water pumping system utilizing by HOMER and LORENTZ software. This research seeks to design a solar water pumping system for a remote location in Kufri, Khushab, Pakistan. With the use of renewable energy, the system is designed to irrigate the land area approximately 30,000 m2 with daily water consumption between 137 and 140 m3. Water demand, total dynamic head (47 m), and sun irradiation were among the site-specific data gathered. An 8.75 kW photovoltaic system, 24-battery storage (Trojan SPRE 12 225), and a 7.11 kW inverter are suggested by the HOMER simulation to achieve 100% renewable operation with no carbon emissions and levelized cost of energy of $0.074/kWh. LORENTZ calculations verified that, with an 8.8 kW solar array, the PSk3-7 C-SJ17-9 submersible pump could deliver 140 m3 per day on average throughout the year. Together, HOMER and LORENTZ can optimize water and energy systems for isolated, off-grid areas. For rural Pakistan, the solution opens the door for net-zero water infrastructure by guaranteeing dependability, cost, and environmental sustainability. Both tools were combined to create a techno-economic, cross-validated solution.

Introduction

The projected 167.7 gigawatts of renewable energy potential in Pakistan are significant yet untapped [1]. Solar energy, particularly photovoltaic technology, stands out as one of the most practical and promising renewable energy sources today. Due to its geographical location within the solar-rich belt, Pakistan ranks among the most solar-abundant countries in the world. The nation has an estimated solar power potential of nearly 100,000 MW, with an average solar insolation level of about 5.5 kWh/m²/day across most regions [2]. Consequently, solar energy offers a viable and sustainable way to meet Pakistan’s growing energy requirements. Reducing dependency on imported fossil fuels, enhancing energy independence, and bolstering the country’s climate-related commitments can all be achieved by harnessing this enormous solar potential [3].

The global shift away from fossil fuel-driven energy sources has been expedited by growing awareness of climate change and environmental impact. Electricity generation through fossil fuels is a major contributor to carbon emissions and atmospheric pollution prompting an urgent transition to cleaner, more sustainable energy alternatives [4], [5]. Shifting to renewable energy is particularly important in areas with high energy needs but limited infrastructure. One such sector is agriculture, especially irrigation which consumes large amounts of energy and could gain considerably from the adoption of renewable sources [6].

In many rural and semi-arid parts of Pakistan, diesel-powered irrigation systems are still commonly used. However, these systems are not only economically burdensome due to fluctuating fuel prices, but also environmentally unsustainable. The need for low-cost, low-maintenance, and eco-friendly irrigation solutions is more pressing than ever [7], [8]. Solar-powered pumping systems are a viable solution, particularly in sun-rich regions like Kufri, Khushab, which receive high levels of solar radiation year-round. The maps or data can be downloaded for free by region or by country (terms of use can be checked on these websites). The global solar irradiation map shown in Fig. 1 gives information about the annual and daily PSH (kWh/m²/year or day) in the different regions of Pakistan [9]. Looking at the map in Fig. 1, Pakistan has approximate daily PSH values of 6 hours.

Fig. 1. PSH map for Pakistan [9].

This study presents a solar-powered water pumping system that was created specifically for the conditions of Kufri, which is located in the Khushab province of Pakistan. Utilizing the region’s copious solar radiation, the proposed method enhances energy accessibility while reducing its adverse environmental impacts. Lorentz Compass, a program that specializes in creating solar water pumping systems, is used to technically model the photovoltaic (PV) system. HOMER Pro, a powerful modeling program for hybrid renewable energy systems, is used to evaluate system viability, energy output, and economics. To guarantee a methodical examination and an understandable presentation of the results, the study is divided into three primary areas.

• Site Characterization

• Proposed Design Architecture

• Simulation Results and Analysis

Method

Selected Site and Data

The site chosen for this research is a remote village and far end from grid connectivity approx. 15 km located in Kufri, Khushab, Pakistan. The selected site for this study is kufri, a rural area located in the Khushab district of Punjab, Pakistan (32°32.8’N, 72°5.5’E) as shown in Figs. 2 & 3.

Fig. 2. Site location Google map [9].

Fig. 3. (a) Site PV module (b) water outlet (c) submersible pump and controller (d) site irrigation land.

The targeted agricultural area spans approximately 30,000 m², primarily intended for vegetable cultivation. Based on crop type and area size, the estimated daily water consumption ranges between 137 and 140 cubic meters and a total dynamic head (TDH) is 47 meters.

The region experiences a semi-arid climate, receiving a solar irradiance of 5.61 kWh/m²/day on average as shown in Fig. 4, ensuring consistent energy availability for photovoltaic (PV) operation throughout the year. These environmental and infrastructural factors collectively support the deployment of a standalone renewable energy system to fulfill local water demands sustainably and make it a favorable location for photovoltaic-based water pumping systems.

Fig. 4. Solar GHI at the site in Homer.

Load Calculation

In Kufri, optimal solar irradiance is consistently available between 10:00 AM and 4:00 PM, this results in an effective daily sunlight window of about six hours. The proposed solar-powered pump system is intended to run constantly during this period throughout the year.

The energy requirement associated with this activity can be expressed by formulation provided in (1).

(1) $$\begin{array}{r}Hydraulicpower,P_h=\frac{Q\times \rho \times \text{g}\times H}{(3.6\times {10}^6)}\end{array}$$

[10]

$$\begin{array}{r}{P}_1=\frac{Hydraulicpower,P_h}{Pumpefficiency,{\eta }_p\times Motorefficincy,{\eta }_m}\end{array}$$

$$\begin{array}{r}{P}_h=\frac{1000\times 9.81\times 47\times 24}{(3.6\times {10}^6)}=3.0738kW\end{array}$$

$$\begin{array}{r}{P}_1=\frac{3.0738}{0.70\times 0.80}=5.48kW\end{array}$$

where ρ = density of water (1000 kg/m³⁾

g = gravitational acceleration (9.81 m/s2)

H = dynamic head (47 m)

Q = water flow (24 m³/hour).

Total energy demand of the pump is given by:

$$\begin{array}{r}Epump=P_1\times Hoursofoperation\end{array}$$

$$\begin{array}{r}Epump=5.5\times 6=33kWhperday\end{array}$$

The computed load was modeled in HOMER, as illustrated in Fig. 5. The daily load profile for the solar water pump, shown in Fig. 6, reveals a consistent 5.5 kW demand over a 6-hour period, specifically from 10:00 to 16:00.

Fig. 5. Load profile in homer.

Fig. 6. Daily load profile of solar water pump.

Proposed Design Architecture

The design of the PV-powered water pumping system was carried out using Lorentz COMPASS and HOMER Pro. Based on site-specific solar irradiance data, Lorentz COMPASS was used for technical sizing and modeling of the solar water pumping system to ensure its ability to meet irrigation requirements. A thorough techno-economic evaluation was then carried out using HOMER Pro, which provided information on system performance, possible optimization, and overall cost-effectiveness. A comprehensive approach to system design and evaluation was made possible by the integration of both software tools.

Homer Pro Design

The schematic layout of the proposed system, as modeled in HOMER, is presented in Fig. 7. The configuration is shown in Table I. A battery-based system is designed to operate reliability every day even on cloudy days.

Fig. 7. Schematic of proposed design.

Table I. Homer Pro Winning System Architecture

Component	Name	Size	Unit
PV	Canadian Solar 345CS6U-345M	8.75	kW
Storage	Trojan SPRE 12 225	24	(4 × 12 V) × 6 strings
System converter	Shenzhen Growatt New Energy Technology Co., Ltd. Growatt 8000MTLP-US (208V)	7.11	kW
Dispatch strategy	HOMER Cycle Charging

Lorentz Compass Based Design

Fig. 8 shows the suggested system’s schematic layout as it is represented in Lorentz Compass. Table II displays the setup. Note that Lorentz Compass is suggesting a water tank for storage instead of batteries (energy storage is a water instead of batteries).

Fig. 8. Schematic of proposed design.

Table II. Lorentz Compass System Architecture

Component	Name	Size	Unit
PV	Longi LR5-72HPH-555M	8.8	kW
Pump size	Lorentz PSk3-7 C-SJ17-9	5.88	kW
System converter	Integrated PSk3 controller with Data Module	8.3	kW
Accessories	Smart Start, Surge Protector, Float Switch, PV Disconnect

Simulation Results and Analysis

Homer Pro Simulation Result

HOMER Pro is used to model the system. According to the simulation results, 8.75 kW of total PV capacity was needed to satisfy the system’s energy requirements. This was achieved using 26 Canadian Solar 345 W panels, arranged in two parallel strings of 13 modules each, resulting in an effective DC input voltage of approximately 500 V, suitable for the selected inverter. The system operates on a 48 V DC bus, supported by a battery bank of 24 Trojan SPRE 12–225 units, configured as six parallel strings of four batteries in series. This configuration offers sufficient autonomy to ensure reliable operation during periods of low solar availability and proposed system layout shown in Fig. 9.

Fig. 9. Proposed AC pump system layout.

The Table II provided appears to be a summary of photovoltaic (PV) system performance metrics. Here’s a brief explanation of each parameter.

As per Table III, the efficiency of system having zero clipped production because of high PV penetration and low LCOE. Having 127% penetration to get overgeneration potential system may require storage. As 4,384 operating hours suggest favorable solar conditions.

Table III. Canadian Solar Electrical Summary

Quantity	Value	Units
Minimum output	0	kW
Maximum output	8.91	kW
PV penetration	127	%
Hours of operation	4,384	hrs/yr
Levelized cost	0.0267	$/kWh
Clipped production	0	kWh

As per Table IV, it shows capacity factor of 20.4% indicates good efficiency for a solar system typical in areas with good sun exposure. 15,605 kWh/year is a substantial annual yield. This system could power a submersible pump for 6 hours.

Table IV. Canadian Solar 345cs6u-345m Statistics

Quantity	Value	Units
Rated capacity	8.75	kW
Mean output	1.78	kW
Mean output	42.8	kWh/d
Capacity factor	20.4	%
Total production	15,605	kWh/yr

Energy Performance

A total annual energy output of 15,605 kWh has been generated by photovoltaic as per Table IV and shown in Fig. 10, supplying an average daily demand for submersible pump to operate. The system maintained continuous operation for 4,384 hours/year as per Table III and shown in Fig. 11, and the inverter operated for 2,678 hours/year, delivering 11,961 kWh/year to the load as per Table V. Battery storage ensured energy availability during intermittent solar hours, with a nominal capacity of 65.2 kWh and autonomy of 37.2 hours. The average daily energy cycle of 0.125 EFC/day, translating to a projected lifetime of 17.6 years.

Fig. 10. Canadian solar 345cs6u-345m output (kW).

Fig. 11. Converter Shenzhen output (kW).

Table V. Converter Electrical Summary & Statistics

Quantity	Value	Units
Hours of operation	2,678	hrs/yr
Energy out	11,961	kWh/yr
Energy in	13,290	kWh/yr
Losses	1,329	kWh/yr
Capacity	7	kW
Mean output	1	kW
Minimum output	0	kW
Maximum output	5	kW

Cost Analysis

Economically, the system demonstrated a net present cost (NPC) of $11,438.85 and a levelized cost of energy (LCOE) of $0.0740/kWh, with zero fuel consumption and CO₂ emissions, reinforcing its sustainability. The energy balance also reported 1,699 kWh/year excess electricity and 328 kWh/year unmet load, with a minor capacity shortage of 6 kWh/year, mostly during early morning or low-irradiance periods as shown in Table VI below.

Table VI. Compare Economics

Parameter	Base system (Diesel)	Proposed system	Remarks
Net present cost	$19,000	$11,439	Renewable is 40% cheaper.
CAPEX	$2,200	$4,572	Disel cheaper initially.
OPEX	$1,210	$531.18	Diesel has higher running cost.
LCOE (per kWh)	$0.40	$0.07	Renewable is 70% cheaper.
CO2 emitted (kg/yr)	2680	0	Environmental advantage.
Fuel consumption	$1,000.00	$0.00	Clean energy.

Lorentz Compass Simulation Result

For simulation-based performance evaluation of a solar-powered water pumping system using the LORENTZ COMPASS 3.1.0.240 tool. The system was configured for agricultural use in Kufri, Khushab, Pakistan (32°N, 72°E). The system is sized to meet a daily water output requirement of approximately 137 m³, considering local climatic conditions, water temperature, and system losses. The simulation parameters include a water temperature of 25°C, a total dynamic head (TDH) of 47 meters, and a dirt loss factor of 5%. The system proposed comprises a submersible pump model PSk3-7 C-SJ17-9 equipped with a Data Module controller, along with a solar photovoltaic (PV) array consisting of 16 modules totaling 8,880 Wp, installed at a tilt angle of 32°. The results demonstrate the feasibility and efficiency of solar-powered water pumping for irrigation and water supply in arid and semi-arid regions as shown in Fig. 12.

Fig. 12. Simulation results in lorentz compass.

Fig. 13 shows the simulation results and average monthly daily output in m³/hr. and also include water output, photovoltaic (PV) energy generation, solar irradiation, rainfall distribution, and ambient temperature patterns throughout the year. As presented in the figure, the average daily water output peaks in April at approximately 155 m³, while July registers a slightly lower output of 125 m³.

Fig. 13. Average monthly performance.

Fig. 14 water output and hourly values breakdown of required approx. 20 m³/h is achieved between 10:00 and 14:00, aligning with peak solar energy input and ambient temperature levels. These results reflect the potential of the system to be finely tuned via the programmable controller to match irrigation schedules efficiently.

Fig. 14. Hourly values.

System Characteristic

The Lorentz PSk3-7 C-SJ17-9 system is a high-efficiency, solar-powered water pumping solution designed for off-grid and hybrid energy environments and detail shown in Fig. 15 and pump chart show in Fig. 16.

Fig. 15. Submersible pump and controller datasheet.

Fig. 16. Pump chart.

Conclusion

This research presents design of an isolated solar water pumping system for a site in Pakistan. Two system designs are presented in Table VII. One use battery while other design needs a water tank. This research shows solar water pumping technology can be depended on and an economically viable alternative to electric and diesel pumps for agricultural irrigation. It is suitable for urban, rural, and community water supplies. System stability and capability by using highly efficient PV modules, system design, and degradation management. Solar pumping is especially attractive in developing countries with significant rural populations and high solar potential.

Table VII. Comparison between Homer Pro and Lorentz Compass

Feature	HOMER Pro	LORENTZ Compass
Main use	System simulation & optimization	Pump selection & system configuration
Storage approach	Water tank, battery, or hybrid	Primarily water tank (no battery)
System components	PV, inverter, pump, storage	PV, controller, pump

Conflict of Interest

The authors declare that there is no conflict of interest related to this research.