Deploying mobilized photovoltaic system between northern and southern hemisphere: Techno-economic assessment

Due to seasonal changes, photovoltaic systems in some areas may remain idle for a long period of time. In order to improve the utilization efficiency and working hours of photovoltaic systems, this paper proposes a concept of a mobilized photovoltaic system which can be transferred between different locations. Based on this idea, a foldable and removable photovoltaic module is designed.

To validate the feasibility of the proposed mobilized photovoltaic system, two cases with transferring routes between Stockholm and Rio Grande (representing high latitude regions, Case 1) and between Rabat and Cape Town (representing mid and low latitude regions, Case 2) are selected. For Case 1, the annual power generation of mobilized photovoltaic systems is 169 MWh and 195 MWh higher than that of the fixed photovoltaic systems (PVs) deployed at Stockholm and Rio Grande. For Case 2, the annual power generation of mobilized PVs are lower than that of the fixed PVs deployed at Rabat and Cape Town. In addition, the levelized cost of electricity of the mobilized photovoltaics is 0.074 $/kWh and 0.099 $/kWh lower than that of the fixed photovoltaics in Case 1. However, the levelized cost of electricity of the mobilized photovoltaics in Case 2 is 0.011 $/kWh higher that of the fixed photovoltaics. The analysis results indicate that deploying transferable PV between high latitude regions in the northern and southern hemispheres has good technical and economic benefits.

Solar power generation has been playing a more important role in energy supply and in the energy transition. Photovoltaic (PV) systems with grid parity have been achieved to compete with fossil electricity generation [1]. Various solar-related technologies and applications, such as utility solar power plants [2], residential rooftop photovoltaics (PVs) [3], infrastructure-integrated PVs [4], small-size systems for special applications like PV irrigation [5], have been developed vigorously in recent years. In the year of 2021, 240 GW of new solar photovoltaic systems were installed and commissioned worldwide, which resulted in the cumulative capacity reaching 1,185 GW, according to the report published by the IEEFA weekly review. The figure reached about 1.2 TW by the end of 2022, according to the Snapshot of Global PV Markets 2023 issued by the International Energy Agency (IEA) [6]. Although photovoltaic technology is now very mature and widely deployed in various places, such as China, Sweden, Brazil, and other countries. However, from the perspective of effective resource utilization, there are still some shortcomings in the current use of photovoltaic resources. Although photovoltaic technology is now very mature and widely deployed in various places, such as China, Sweden, Brazil, and so on. However, from the perspective of effective resource utilization, there are still some shortcomings in the current use of photovoltaic resources. Due to the change of seasons, the solar radiation is abundant only for a certain period of time, while the solar radiant intensity is very weak for other long periods of time. Therefore, photovoltaic systems deployed in many places will remain idle for a long period of time. For example, in Sweden, the winter is very long and the solar radiant intensity is very weak, so the power generation efficiency of the photovoltaic system is very low during this period, leading to the waste of photovoltaic resources in winter. In response to the serious seasonal interference faced by photovoltaic systems, this paper proposes a mobilized photovoltaic system which can be transferred seasonally between different locations. In order to study the feasibility of the proposed transferred photovoltaic system, this paper conducted a technical and economic evaluation of the mobilized photovoltaic system.

To achieve the mobility of photovoltaic systems, it is first necessary to make them portable and easy to disassemble. In recent years, portable solar power generation systems based on different foldable structures have been designed and prototyped by some researchers [7], [8], [9]. In order to increase compactness and to facilitate transportation, Attavane et al. [10] developed a foldable solar module using extremely thin crystalline silicon cells. Although this kind of flexible photovoltaic cells can be easily folded and moved, their folding and unfolding requires manual operation and needs to be folded and unfolded one by one, which diminishes their disassembly efficiency. To achieve efficient folding, some foldable mechanisms have been investigated, based mainly on mechanical structures. Qi et al. and Pan et al. presented a portable PV system based on an M-type-based folding mechanism for powering vehicle air conditioners [11], [12]. The prototype was fabricated and the experiment results showed that the proposed PV system can be flexibly expanded and folded. When the solar system is not in operation, it can be stored in a vehicle cabin to avoid dust accumulation and rain impact. Similarly, Zhang et al. [13] designed another portable solar power device based on a foldable-flower mechanism for powering vehicle cabin cooling systems. The field test results demonstrated that the studied solar power system can be unfolded and folded like a folding fan. Qi et al. [14] proposed a foldable wind-PV power generation system using an umbrella mechanism for powering electrical facilities on highways. Although all of the above PV folding mechanisms can make PV systems easy to disassemble, assemble, and move, they cannot quickly adjust the angle of the photovoltaic system and are not suitable for large photovoltaic power stations. Therefore, this article first proposes a bracket mechanism that can quickly fold photovoltaic systems to facilitate efficient disassembly and installation of photovoltaic systems.

In addition to designing a foldable mechanism for easy disassembly and assembly of photovoltaic systems, the economic and energy performance of mobilized photovoltaic systems still needs to be analyzed in depth, which is the key to evaluating the feasibility of deploying mobilized photovoltaic systems between different locations. In terms of economy, it is necessary to analyze the costs and benefits of the proposed mobilized photovoltaic systems. First, the cost related to the manufacture, transportation and installation of solar panels significantly affects the economics of PV systems [15], [16]. Different types of photovoltaic panels are different in costs. For instance, p-type multi-silicon passivated emitters and rear cells, wafer-based monocrystalline silicon cells, and GaAsP/Si dual junction solar cells are 0.22 $/W [17], 0.37 $/W [18], and 1.5 $/W [19], respectively. For perovskite solar panels, Song [20] indicated that the direct manufacturing cost of a standard perovskite cell is 0.41 $/W, and Chang [21] proposed that the lowest production cost of roll-to-roll technique-based perovskite cell is 0.5 $/W. In this paper, due to its mature technology and relatively low cost, polycrystalline silicon photovoltaic cells are chosen for mobile photovoltaic systems. In terms of energy performance, it is necessary to consider both the energy output of mobilized photovoltaic systems and the energy consumption caused by their manufacturing, installation, and transportation. The energy consumption during the manufacturing process also varies for different solar cells. The energy required for manufacturing multi-crystalline photovoltaics is about 19.55 MJ/W [22], while the energy consumption for manufacturing perovskite cells varies from 1.64 to 2.58 MJ/W [23]. For mobilized PV systems, extra transportation costs and energy consumption will be produced. There are obvious differences in the cost and energy requirements of different modes of transportation [24], [25]. In general, the cost of long-distance water and rail transportation is relatively lower compared with road and air transportation [26], [27]. As to the energy consumption per tonne-km, rail transportation corresponds to the lowest value, followed by water transportation [28], in comparison with road and air transportation modes. Based on these literature materials, this paper considers using waterway transportation to transport mobile photovoltaic systems.

Therefore, the first research motivation of this paper is to design a foldable photovoltaic system suitable for large photovoltaic power plants. The second research motivation is to propose a photovoltaic system that can be transferred between different locations to improve the utilization efficiency of photovoltaic resources. The designed foldable PV system mainly includes solar panels, retractable support, elevation adjustment rod, and other components. Technically, this new PV system can easily achieve the folding and unfolding of PV modules and the elevation angle adjustment of solar panels. The photovoltaic system can be easily transported and installed due to its foldability into stacked form. In order to evaluate the feasibility of the proposed mobilized PV system. Two pairs of locations, including Stockholm to Rio Grande and Rabat to Cape Town, are selected for the case study. The cost, energy consumption, power generation, and economic benefits of the proposed mobilized PV system are investigated and compared with traditional fixed PVs. The main innovations of this paper are summarized as follows: (1) PVs that can be mobilized in the north–south hemispheres is proposed for the first time; (2) Foldable PVs bracket is designed for easy PVs transportation; (3) Locations at different latitude are chosen for case study; (4) Techno-economic performance of the mobilized PVs is studied and results show that the mobilized PVs deployed in high latitudes has favorable performance.

The rest of this paper is organized as follows. Section 2 presents the methodology, including the system design of the mobilized PV, case study, energy consumption and cost analysis, and power generation and economic benefits analysis. Section 3 presents results and discussion about energy consumption and cost, annual energy yield and levelized cost of electricity, sensitivity analysis, and future work concerning the new mobilized PV system. Finally, some conclusions are given in Section 4.

Section snippets

Methodology

In this paper, a foldable mechanism-based mobilized PV system is conceptualized, designed and evaluated. The architecture of the proposed PV is presented in Fig. 1. The innovative PV design can easily achieve transportation between two locations, and even between the northern and southern hemispheres. The purpose of this mobility is to increase the availability of the PV system for more operation hours. Compared to traditional fixed PVs, this new PV system design has the characteristics of

Energy consumption and cost of the mobilized PV system

In this paper, in order to simplify the analysis and discussion, the capacity of the PV system is considered as 1 MW. For the traditional fixed deployment method, two sets of PV systems with 1 MW need to be installed in location A and location B, respectively. For the mobilized deployment approach, only one PV system with 1 MW needs to be involved, because the PV system can be transported between the two locations according to solar radiation conditions. By comparing PV support structures, we

Conclusions

In order to improve the utilization efficiency and working hours of photovoltaic systems, this paper proposed a module-based mobilized PV system which can be transported between different locations. Technically, the studied PV system can be folded into a portable size for easy transportation. The technical and economic performance of the mobilized photovoltaic systems have been analyzed and evaluated in detail. Two transportation routes—from Stockholm to Rio Grande (Case 1) and from Rabat to

Declaration of competing interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Acknowledgments

This work was supported by the Special Posts of Guizhou University (No. [2023] 27), the 2023 General Undergraduate University Scientific Research Project of Guizhou Provincial Department of Education (Guizhou Educational Technology?2022?107), the National Key Research and Development Program of China (2018YFE0196000), the Swedish Knowledge Foundation (KK-stiftelsen) “FREE” project, and the Swedish Research Council “Synergies of distributed multienergy systems for efficient integration of large

References (41)

https://www.sciencedirect.com/science/article/abs/pii/S0038092X24000598