Techno-Economic Investigation of Standalone Photovoltaic Energy Systems for Rural Areas of Quetta ^†

Abstract

The purpose of this techno-economic study is to investigate the potential of the implementation of standalone photovoltaic (PV) energy systems in rural areas of Quetta, Pakistan. This study focuses on alleviating the region’s energy crisis and giving the local population access to clean and sustainable energy. The technique used entails data collection, load demand analysis, technical and economic evaluation, site selection, and data interpretation. The findings and discussion provide an estimate of PV energy systems’ lifetime costs, annual maintenance expenses, and energy prices. The results show that standalone PV energy systems are a feasible and financially viable option for electricity generation in Quetta’s rural areas that operates via monitoring the economic development and environmental sustainability of the region. Three plants are proposed for generating 26.8 KW, 15 KW, and 6.8 KW of power, and it is demonstrated that green and clean energy can be provided for domestic consumers at reasonable unit costs of PKR. 21.33, PKR. 21.9, and PKR. 23.89, respectively.

1. Introduction

Pakistan’s energy crisis is a growing concern for all stakeholders due to the nation’s incremental population growth and decremental economic growth. It is important to explore the potential of renewables in Pakistan to generate cleaner and sustainable energy. The most important globally employed renewable energy resources are solar energy, wind energy, hydropower, geothermal energy, bioenergy, and ocean thermal energy conversion cycles (OTEC) [1]. Balochistan province is particularly affected by this energy and economic crisis. Pakistan needs an effective, long-term energy plan to bridge the supply and demand gap, which has been precipitated by obsolete power plants, inadequate financial resources, and poor transmission and distribution (T&D) infrastructure. Domestic energy resources in Pakistan’s Balochistan province have a combined capacity of 500.041 TWh, which can be used to address energy crises. Pakistan’s energy consumption from 2018 to 2030 is expected to be in the range from 312 TWh to 399 TWh [2]. To fulfill this demand, serious efforts are required from researchers, government officials, higher authorities, and decision makers.

Studies have been carried out on different locations of Balochistan to explore the potential of photovoltaic energy. Gohram et al. [3] carried out a techno-economic investigation of a solar power plant in Quetta with a 50 MW capacity and concluded that the production of 91.980 GWh of energy (per year), with a USD 59.689 million capital cost and a USD 0.9 million (per year) O&M cost, can be achieved. Noman et al. [4] conducted an economic analysis of photovoltaic (PV) installations in big cities in Pakistan (Karachi, Quetta, Multan, Lahore, and Peshawar) and concluded that PV is a suitable replacement for non-renewable energy sources that can decrease the load on the national grid by 60%, if installed at higher scales. Pakistan has installed a 100 MW solar system in Bahawalpur that has five modules, each having a capacity of 20 MW [5].

The current study was carried out to render the rural areas of Balochistan energy-independent and provide some comfort for the local population. The location selected for this study is Chashma Achozai Garden Town. Hardware, including PV panels, batteries, and invertors, have been chosen such that the best output can be attained at low capital and maintenance costs. The cost of electricity per kWh has been calculated, and the levelized cost of electricity has been evaluated. Furthermore, break-even and payback times were calculated for three power plants with capacities of 6.8 KW, 15 KW, and 26.8 KW.

2. Materials and Methods

The important information used in the current study was obtained using a pyranometer installed at BUITEMS Quetta by the World Bank, information from the energy info website [6], software programs like RET Screen and PVsyst, and information from Meteonorm and NASA. The mentioned pyranometer was used to measure the study area’s sun radiation levels on a regular basis. Software programs like RET Screen and PVsyst provided functionalities for simulating and analyzing energy systems, including solar energy. Meteonorm and NASA also provided information on temperature, solar radiation, and other climatic variables. The power-consumption-related data of Chashma Achozai Garden Town was collected using a questionnaire, which provided estimates of monthly/daily electricity consumption.

Technical and economic analyses were conducted to evaluate the feasibility and financial viability of the analyzed solar energy projects. Solar radiation data were used to estimate solar energy potential, and statistical analysis and modelling approaches were used to evaluate variability and availability.

Financial modelling tools were used to assess the solar energy projects’ financial viability and economic viability, considering capital costs, operation and maintenance costs, energy tariff rates, financing alternatives, and social and environmental aspects.

It is important to carry out data collection for solar energy projects in order to determine a project’s viability and system development characteristics and perform a corresponding performance evaluation. Solar resource data include global horizontal irradiance (GHI), diffuse horizontal irradiance (DHI) levels, and direct normal irradiance (DNI). Historical weather information includes past temperatures, cloud cover, and precipitation levels that have affected the production of solar energy. Site-specific data include latitude and longitude, shading analysis information, topography, economic and financial data, regulations and permits, local laws, environmental impact assessments, performance and monitoring data, and reliability reports. Radiation statistics of Quetta city were gathered for 24 months, with the greatest values of global horizontal irradiance (GHI), incidence angle modifier (IAM) losses, and shadings recorded in May, June, and July, amounting to 228.5, 231.7, and 223.7 KWh/m², respectively.

The load profile divides a load into three phases. This method considers the load demand and load calculations to obtain the daily maximum consumption for

• 3 to 4 houses (6.8 KW);
• 10 to 15 houses (15 KW);
• 20 to 25 houses (26.5 KW).

Levelized cost of electricity (LCOE), annual operation and maintenance (O&M) cost, and total cost were calculated using the following equations:

LCOE = Total Cost/Total Electricity Produced

(1)

Annual unit O&M cost = Annual O&M cost/Plant size

(2)

Total cost = Installation cost + Maintenance cost

(3)

3. Results and Discussion

The details of the hardware suggested in this work along with the installation and maintenance costs (excluding consumables) are tabulated in

Table 1. Quantity and Specifications of the Hardware suggested along with costs.

Load (KW)	No. of Panels	Panels’ Specifications	No. of Batteries	Batteries’ Specifications	No. of Inverters	Inverters’ Specifications	Installation Cost (PKR)	Maintenance Cost per Year (PKR)
6.8	20	Mono 340W-Power Generic Panels	128	ANTBatt 12 V-101an Li-ion	1	Generic MPPT Convertor	6,803,800	1–2% of initial cost
15	44	Mono 340W-Power Generic Panels	272	Abwatt 12 V-101an Li-ion	1	Generic MPPT Convertor	14,073,400	1–2% of initial cost
26.5	80	Mono 340W-Power Generic Panels	496	ANTBatt 12 V-101an Li-ion	1	Generic MPPT Convertor	25,431,000	1–2% of initial cost

.

The selected PV panels, batteries, and inverters were chosen based on their efficiency and cost-effectiveness. Three different power plants, with loads of 26.8 kW, 15 kW, and 6.8 kW, were simulated using PVsyst software. This analysis included both economic and technical aspects. For the 26.8 kW load, the software estimated an installation cost of PKR 25,431,000. The annual maintenance cost was PKR 30,000, and the energy cost was PKR 22.35/kWh. A daily input/output diagram for this plant is shown in Figure 1a.

For the 15 KW load, the installation cost was estimated to be PKR 14,073,400, with an energy cost of PKR 21.922/kWh. For the 6.8 kW load, the installation cost was projected to be PKR 6,803,800, with an energy cost of PKR 19.98/kWh. The maintenance costs (excluding consumables) of all three plants were approximated to account for 1–2% of initial cost. The estimated lifespan of the PV panels is 25 years, while the batteries have a lifespan of 3–5 years.

The cost of electricity calculated in this study is very economical compared to the rates of electric power supplied by the national grid, which will increase even further due to the current financial crisis the country is experiencing; hence, the suggested plants are the need of the hour.

The proposed plants have shown great promise, and their investment return is quite high. Figure 1b presents the break-even points of the three proposed plants. In Figure 1b, Cost 1, Cost 2, and Cost 3 represent the total cost of the plants with a capacity of 6.8 KW, 15 KW, and 26.8 KW, respectively, while Return 1, 2, and 3 represent the total outcomes for the respective plants. The unit price of the national grid is assumed to be PKR 26/kWh for the calculation of the break-even point, and the prices per unit for the proposed plants of 6.8 KW, 15 KW, and 26.8 KW in PKR are 23.89, 21.9, and 21.33, respectively.

4. Conclusions

The primary purpose of this study is to highlight the techno-economic feasibility of standalone PV plants for rural areas in Quetta. This study reveals that 140 kW/day energy can be received by the analyzed PV plates. Energy can be produced for as cheap as PKR 21.33/kWh for 20 years. Investments can give high returns, as the payback time is about 17 years. Massive projects can have even better returns, provided that hardware is chosen wisely. This energy-deprived region can become energy-efficient, and the local population can gain access to a clean and green power supply, which is economical and reliable.