Report on Optimizing Solar Photovoltaic Array Performance to Advance Sustainable Development Goals

Executive Summary

This report analyzes the performance of different interconnection schemes for solar photovoltaic (PV) arrays under partial shading conditions (PSCs). The primary objective is to identify optimal configurations that mitigate power loss, thereby enhancing the efficiency and reliability of solar energy systems. This research directly supports the achievement of several United Nations Sustainable Development Goals (SDGs), particularly SDG 7 (Affordable and Clean Energy), SDG 9 (Industry, Innovation, and Infrastructure), SDG 11 (Sustainable Cities and Communities), and SDG 13 (Climate Action). By maximizing the power output from PV installations, especially in urban environments prone to shading, this work contributes to building resilient sustainable infrastructure and promoting the global transition to clean energy.

1.0 Introduction: Solar Energy and the Sustainable Development Agenda

Solar energy is a cornerstone of the global strategy to achieve a sustainable future. Its widespread availability and scalability make it a critical tool for advancing SDG 7 (Affordable and Clean Energy). However, the operational efficiency of solar PV systems is often compromised by partial shading, a common issue in both large-scale solar farms and urban rooftop installations. This power loss undermines the reliability and economic viability of solar technology, slowing progress towards SDG 13 (Climate Action).

Partial shading, caused by obstructions like buildings, trees, and clouds, leads to a significant reduction in energy output. This challenge is particularly acute in the context of SDG 11 (Sustainable Cities and Communities), where space is limited and shading from adjacent structures is unavoidable. Addressing this issue through innovative infrastructure solutions is essential for unlocking the full potential of solar power. This report investigates how modifying the electrical interconnection scheme of PV modules can mitigate these losses, thereby enhancing the performance and dependability of clean energy systems.

1.1 Investigated Interconnection Schemes

Numerous strategies exist for interconnecting PV modules. This analysis focuses on the two most prevalent configurations:

• Series-Parallel (SP): A simple configuration with minimal wiring complexity and lower installation costs. However, it is known to be highly susceptible to power loss under PSCs.
• Total-Cross-Tied (TCT): A more complex arrangement with additional electrical connections between module strings. It is reputed to offer greater resilience and higher power output under most shading scenarios.

The comparative analysis of these schemes provides critical insights for designing more robust and efficient solar infrastructure, a key target of SDG 9.

2.0 Analysis of PV Array Performance Under Shading Conditions

A 2×3 PV array was simulated using MATLAB/Simulink to evaluate the performance of SP and TCT configurations under various predictable shading patterns. The goal was to determine which scheme maximizes the Maximum Power Point (MPP), ensuring the highest possible energy yield and contributing directly to the targets of SDG 7.

2.1 Vertical Shading Pattern (VSP) Analysis

In this scenario, shade moves vertically across the columns of the PV array. The key findings were:

1. One Shaded Column: The TCT configuration consistently outperformed the SP configuration, yielding higher MPP. This suggests TCT is preferable for narrow, vertical shading patterns.
2. Two Shaded Columns: TCT performed better in most cases. However, SP yielded more power when only the bottom modules of the two columns were shaded.
3. Three Shaded Columns: The SP configuration produced more power in the majority of cases, making it the preferred choice when a large proportion of the array’s columns are shaded.
4. All Columns Shaded: Both configurations produced identical power output. In this case, the SP scheme is recommended due to its simpler wiring and lower installation cost, aligning with the principles of affordable infrastructure under SDG 9.

2.2 Horizontal Shading Pattern (HSP) Analysis

In this scenario, shade moves horizontally across the rows of the PV array. The results indicated:

1. One Shaded Row: The SP configuration delivered equal or greater power in most cases. TCT was only superior when a single module in the row was shaded.
2. Two Shaded Rows: The results were mixed. TCT was superior when one or two modules per row were shaded, while SP performed better when three modules were shaded.
3. Three or More Shaded Rows: The TCT configuration consistently yielded higher power, making it the optimal choice for wide, horizontal shading patterns. When all modules were shaded, both schemes performed identically, favoring the simpler SP configuration.

3.0 Key Findings and Recommendations for Sustainable Infrastructure

The simulation and experimental validation confirm that the choice of interconnection scheme is not universal but depends critically on the anticipated shading pattern. This strategic selection is a vital innovation for developing resilient and efficient renewable energy systems (SDG 9).

3.1 Decision Framework for Optimal Configuration

A clear principle emerged from the analysis, which can guide the design of PV systems for maximized output and contribution to the SDGs:

• Prefer the Total-Cross-Tied (TCT) configuration when: The number of shaded rows is greater than the number of shaded columns. TCT’s ability to redistribute current effectively mitigates power loss in these scenarios.
• Prefer the Series-Parallel (SP) configuration when: The number of shaded columns is greater than or equal to the number of shaded rows. Its simpler design offers a cost-effective and efficient solution for these specific conditions.

This framework provides a practical tool for engineers and planners to enhance the performance of solar installations, particularly in dense urban environments where shading is a primary concern (SDG 11).

3.2 Experimental Validation

The simulation results were validated through experiments on a physical 2×3 PV array. The practical measurements confirmed the core findings: TCT performed better when more rows than columns were shaded, and SP was superior when more columns than rows were shaded. This validation reinforces the reliability of the proposed decision framework.

4.0 Conclusion: Advancing Clean Energy through Optimized Design

Mitigating power loss from partial shading is a significant challenge that directly impacts the effectiveness of solar energy as a tool for sustainable development. This report demonstrates that the strategic selection of a PV array’s interconnection scheme can substantially improve its performance, reliability, and energy yield.

The findings show that while the TCT configuration is often superior, the simpler and less expensive SP configuration can match or exceed its performance under specific, predictable shading conditions. By applying the decision framework outlined in this report—choosing a configuration based on the relationship between shaded rows and columns—solar energy systems can be optimized for their specific environment.

Ultimately, this research provides a clear, actionable strategy to make solar power more efficient and dependable. This directly accelerates progress towards SDG 7 (Affordable and Clean Energy) and SDG 13 (Climate Action) by maximizing the output of every installation. Furthermore, by providing innovative solutions for resilient infrastructure (SDG 9), it empowers the development of more Sustainable Cities and Communities (SDG 11) powered by clean energy.

Analysis of Sustainable Development Goals (SDGs) in the Article

1. Which SDGs are addressed or connected to the issues highlighted in the article?

The article’s focus on improving the efficiency and reliability of solar photovoltaic (PV) systems, particularly under adverse conditions like partial shading, connects directly to several Sustainable Development Goals. The primary goal addressed is SDG 7, with strong links to SDG 9 and SDG 11.

• SDG 7: Affordable and Clean Energy

  This is the most relevant SDG. The article is fundamentally about enhancing the generation of clean energy from solar resources. By investigating methods to mitigate power loss from partial shading, the research aims to make solar energy more efficient, reliable, and thus more viable as a clean energy source. The introduction explicitly states, “…solar energy has the potential to meet a large portion of the worlds’ growing demands for energy, it is important to make efficient use of electricity generated by this way.”

• SDG 9: Industry, Innovation, and Infrastructure

  The article details a technological innovation aimed at improving sustainable infrastructure. The comparison of different interconnection schemes (SP and TCT) and the development of a flowchart to select the optimal configuration represent scientific research and technological advancement. This work contributes to building resilient and sustainable infrastructure by making solar installations more productive and dependable, which is a core aspect of SDG 9.

• SDG 11: Sustainable Cities and Communities

  The article specifically mentions the challenges of partial shading in urban and built-up environments, stating, “…the rooftops installations or building integrated photovoltaic systems has more probability of encountering some obstacles such as nearby trees, chimney, towers etc.” By providing solutions to improve the efficiency of these systems, the research supports the development of sustainable cities that can integrate renewable energy sources effectively, reducing their environmental footprint and increasing energy resilience.

2. What specific targets under those SDGs can be identified based on the article’s content?

Based on the article’s content, several specific SDG targets can be identified:

1. Targets under SDG 7 (Affordable and Clean Energy)

   • Target 7.2: “By 2030, increase substantially the share of renewable energy in the global energy mix.” The entire article is dedicated to improving the performance of solar PV, a key renewable energy technology. By making it more efficient and reliable, the research helps accelerate its adoption and increase its share in the energy mix.
   • Target 7.3: “By 2030, double the global rate of improvement in energy efficiency.” The study’s primary goal is to improve the energy efficiency of PV arrays by minimizing power losses. The conclusion states the study highlights “the importance of selecting the appropriate interconnection scheme to maximize efficiency while minimizing complexity.”
   • Target 7.a: “By 2030, enhance international cooperation to facilitate access to clean energy research and technology… and promote investment in energy infrastructure and clean energy technology.” This scientific paper is a form of research that contributes to the global body of knowledge on clean energy technology, specifically addressing a technical challenge to improve PV system performance.

2. Targets under SDG 9 (Industry, Innovation, and Infrastructure)

   • Target 9.4: “By 2030, upgrade infrastructure and retrofit industries to make them sustainable, with increased resource-use efficiency and greater adoption of clean and environmentally sound technologies…” The research provides a method for upgrading PV infrastructure (the interconnection scheme) to increase its resource-use efficiency (generating more power from the same panels under shading).
   • Target 9.5: “Enhance scientific research, upgrade the technological capabilities of industrial sectors in all countries…” The paper is a direct product of scientific research, complete with simulations and “experimental validation,” which upgrades the technological understanding of how to build more effective solar arrays.

3. Targets under SDG 11 (Sustainable Cities and Communities)

   • Target 11.6: “By 2030, reduce the adverse per capita environmental impact of cities…” By improving the feasibility and output of rooftop and building-integrated solar panels, the research helps cities generate more clean energy locally, reducing their reliance on fossil fuels and thus their overall environmental impact.

3. Are there any indicators mentioned or implied in the article that can be used to measure progress towards the identified targets?

Yes, the article mentions and implies several specific, measurable indicators that align with the identified targets.

• Indicators for SDG 7 Targets

  • Maximum Power Point (MPP) Power: This is the most direct and frequently used indicator in the article. The entire performance analysis is based on measuring and comparing the MPP power (in Watts) of different PV array configurations under various shading scenarios. Tables 3 through 11 explicitly list MPP power values, which serve as a direct measure of energy efficiency and output. This is a key indicator for progress towards Target 7.3.
  • Energy Efficiency: While not given as a single percentage, the concept of maximizing efficiency is central. The conclusion states the goal is to “maximize efficiency while minimizing complexity.” The comparison of output power under partial shading versus uniform conditions is an implied measure of efficiency improvement.
  • Reliability: The article mentions that power loss from shading leads to a “lack of reliability for this technology among consumers/users.” By proposing solutions to mitigate this loss, the research aims to increase the system’s reliability, an important qualitative indicator for the adoption of renewable energy (Target 7.2).

• Indicators for SDG 9 Targets

  • Performance of Interconnection Schemes (SP vs. TCT): The study uses the comparative performance of different technological configurations as an indicator of innovation. The flowchart in Figure 14 provides a decision-making tool, indicating a mature level of technological understanding that can be applied in the industry (Target 9.4).
  • Simulation and Experimental Validation: The presence of both simulation results (e.g., Figures 5-8) and experimental validation (Section “Experimental validation,” Tables 13 & 14) serves as an indicator of robust scientific research, contributing to Target 9.5.

• Indicators for SDG 11 Targets

  • Performance of Rooftop/Building-Integrated PV Systems: The article’s focus on shading patterns caused by “nearby trees, chimney, towers etc.” implies that the efficiency and power output of these specific urban installations are key indicators. Improving their performance directly measures progress in making cities more sustainable (Target 11.6).

4. Table of SDGs, Targets, and Indicators

Source: nature.com