Minimum Required PV Capacity for Solar-Powered EV Charging: A Case Study of Route Reassignment for Clinic Shuttle Services in Japan

Koki Kumaoka, Haru Morikawa, Nobumasa Matsui, Jiyoung Choi, Yuji Mizuno

Abstract


This study explores the determination of an appropriate photovoltaic (PV) capacity for charging electric vehicles (EVs) through a case study on the electrification of clinic shuttle services in Japan. The purpose is to evaluate the feasibility of sustaining EV shuttle services using solar energy alone, without dependence on grid electricity, under diverse solar conditions. Recent efforts toward energy efficiency and decarbonization have accelerated the integration of renewable energy technologies and EVs. In the healthcare sector, shuttle services for elderly and mobility-impaired patients are widely operated, and their electrification is increasingly regarded as an important measure for reducing environmental impact. However, EV operation faces challenges related to charging availability and the variability of PV power generation. This study analyzes the correlation between solar irradiance and sunshine duration and classifies weather conditions into three categories based on a normal distribution of solar irradiance characteristics. Using these categories, month-long charging simulations were conducted under varying meteorological conditions, based on state of charge (SoC) data derived from actual driving records of clinic shuttle services. In addition, the impact of operational strategies was investigated by modifying shuttle route assignments while keeping the number of EVs fixed to reflect actual clinic operations. By redistributing driving distances among EVs, the effect of operational load balancing on charging feasibility and required PV capacity was evaluated. The results show that appropriate route reassignment can significantly reduce the required PV capacity; for example, under low-solar-irradiance conditions, the required PV capacity was reduced by approximately 40%.

Keywords


photovoltaic; electric vehicles; solar irradiance; sunshine duration; clinic; state of charge

Full Text:

PDF

References


Council for the Promotion of Global Warming Countermeasures in Hospitals, “Low Carbon Society Action Plan for Hospitals: 2021 Follow-up Fact-Finding Survey Report,” Tokyo, Japan, 2022.

Council for the Promotion of Global Warming Countermeasures in Hospitals, “Low Carbon Society Action Plan for Hospitals: 2023 Follow-up Fact-Finding Survey Report,” Tokyo, Japan, 2024.

M. M. R. Ahmed, S. Mirsaeidi, M. A. Koondhar, N. Karami, E. M. Tag-Eldin, N. A. Ghamry, R. A. El-Sehiemy, Z. M. Alaas, I. Mahariq, and A. M. Sharaf, “Mitigating uncertainty problems of renewable energy resources through efficient integration of hybrid solar PV/wind systems into power networks,” IEEE Access, vol. 12, pp. 30311–30328, 2024.

A. Al Hadi, C. A. Santos Silva, E. Hossain, and R. Challoo, “Algorithm for demand response to maximize the penetration of renewable energy,” IEEE Access, vol. 8, pp. 55279–55288, 2020.

Agency for Natural Resources and Energy, “Annual Report on Energy 2023 (Energy White Paper 2024),” Ministry of Economy, Trade and Industry, Tokyo, Japan, June 2024.

Y. Mizuno, M. Tanaka, Y. Tanaka, F. Kurokawa, and N. Matsui, “New sustainable operation method for a power grid without an energy storage system: A case study of a hospital in Japan,” International Journal of Renewable Energy Research (IJRER), vol. 12, no. 3, pp. 1289–1300, 2022.

R. Jin, C. Lu, and J. Song, “Manage distributed energy storage charging and discharging strategy: Models and algorithms,” IEEE Transactions on Engineering Management, vol. 69, no. 3, pp. 755–764, 2020.

N. Christiansen, M. Kaltschmitt, and F. Dzukowski, “Electrical energy consumption and utilization time analysis of hospital departments and large scale medical equipment,” Energy and Buildings, vol. 131, pp. 172–183, 2016.

F. Angizeh, A. Ghofrani, E. Zaidan, and M. A. Jafari, “Resilience-oriented behind-the-meter energy storage system evaluation for mission-critical facilities,” IEEE Access, vol. 9, pp. 80854–80865, 2021.

A. Dogan, D. Guven, M. O. Kayalica, and A. A. Bayar, “Scheduling model for a trigeneration system with energy storage unit: A hospital application,” IEEE Transactions on Engineering Management, vol. 71, pp. 6146–6159, 2024.

R. Colucci, I. Mahgoub, H. Yousefizadeh, and H. Al-Najada, “Survey of strategies to optimize battery operation to minimize the electricity cost in a microgrid with renewable energy sources and electric vehicles,” IEEE Access, vol. 12, pp. 8246–8261, 2024.

S. Koli, S. Patil, B. B. S., S. Naik, K. R. Patil, and S. M., “Study of energy cost optimization for integration of microgrid to electric vehicles,” in Proc. 3rd International Conference for Innovation in Technology (INOCON), Bangalore, India, 2024, pp. 1–6.

H. Masrur, M. Shafie-Khah, M. J. Hossain, and T. Senjyu, “Multi-energy microgrids incorporating EV integration: Optimal design and resilient operation,” IEEE Transactions on Smart Grid, vol. 13, no. 5, pp. 3508–3518, 2022.

A. Abuelrub, F. Hamed, J. Hedel, and H. M. K. Al-Masri, “Feasibility study for electric vehicle usage in a microgrid integrated with renewable energy,” IEEE Transactions on Transportation Electrification, vol. 9, no. 3, pp. 4306–4315, 2023.

M. Ahmadigorji, M. Mehrasa, A. Labonne, A. Hably, and S. Bacha, “A robust multiobjective optimization strategy for power management in a PV-integrated G2V/V2G system,” IEEE Transactions on Industrial Informatics, vol. 21, no. 8, pp. 5822–5833, 2025.

A. AbuElrub, F. Hamed, and O. Saadeh, “Microgrid integrated electric vehicle charging algorithm with photovoltaic generation,” Journal of Energy Storage, vol. 32, 101858, 2020.

I. A. Zenhom, M. F. Shaaban, and W. A. Omran, “Grid interactive charging of EVs in PV-powered parking lots considering uncertainties,” IEEE Access, vol. 11, pp. 111292–111301, 2023.

I. Jokinen and M. Lehtonen, “Flexibility of electric vehicle charging with demand response and vehicle-to-grid for power system benefit,” IEEE Access, vol. 12, pp. 131419–131441, 2024.

N. Das, A. Haque, H. Zaman, S. Morsalin, and S. Islam, “Domestic load management with coordinated photovoltaics, battery storage and electric vehicle operation,” IEEE Access, vol. 11, pp. 12075–12087, 2023.

X. Liu, “Research on flexibility evaluation method of distribution system based on renewable energy and electric vehicles,” IEEE Access, vol. 8, pp. 109249–109265, 2020.

S. Li, P. Zhao, C. Gu, J. Li, S. Cheng, and M. Xu, “Battery protective electric vehicle charging management in renewable energy system,” IEEE Transactions on Industrial Informatics, vol. 19, no. 2, pp. 1312–1321, 2023.

F. Dincer and E. Ozer, “Numerical and experimental analysis of photovoltaic-integrated energy storage system for electric vehicle fast charging,” IEEE Access, vol. 13, pp. 129127–129142, 2025.

A. Wego, “Field test on energy flows in residential buildings with PV systems, heat pump based heating and battery electric car operation,” in Proc. 2023 International Interdisciplinary PhD Workshop (IIPhDW), Wismar, Germany, 2023, pp. 1–4.

A. Shukla, H. Shukla, S. K. Yadav, J. Singh, and R. B. Singh, “Solar powered electric vehicle charging station with integrated battery storage system,” Energy Storage, vol. 6, no. 8, e70077, 2024.

B. Singh, A. Verma, A. Chandra, and K. Al-Haddad, “Implementation of solar PV-battery and diesel generator based electric vehicle charging station,” IEEE Transactions on Industry Applications, vol. 56, no. 4, pp. 4007–4016, 2020.

K. Kumaoka, H. Morikawa, N. Matsui, J. Choi, and Y. Mizuno, “Determination of PV capacity for charging: A case study on the electrification of clinic shuttle services in Japan,” in Proc. 14th International Conference on Renewable Energy Research and Applications (ICRERA), Vienna, Austria, 2025, pp. 1965–1969.

A. P. Dobos, PVWatts Version 5 Manual, National Renewable Energy Laboratory (NREL), Golden, CO, USA, Tech. Rep. NREL/TP-6A20-62641, 2014.

J. A. Duffie and W. A. Beckman, Solar Engineering of Thermal Processes, 4th ed. New York, NY, USA: John Wiley & Sons, 2013.

Ministry of the Environment, Japan, “Renewable Energy Potential System (REPOS),” Available: https://repos.env.go.jp/web/. Accessed: Mar. 2026.

W. F. Mbasso, I. Dagal, M. K. Singla, M. S. Shaikh, A. Smerat, A. M. Al Fatais, A. S. Almufih, and R. E. Al Mamlookol, “Drift-aware global intelligent optimization and advanced control of photovoltaic MPPT under complex operating conditions: A Cameroon case study,” Energy Engineering, 2026, doi:10.32604/ee.2026.072751.

W. F. Mbasso, A. Harrison, P. Jangir, I. Dagal, M. Khishe, A. Smerat, S. Chebaane, and T. Saidani, “Reliability-conscious power flow optimization in hybrid renewable microgrids: A case study in Sub-Saharan Africa using Gauss–Seidel and metaheuristic techniques,” International Journal of Electrical Power & Energy Systems, vol. 173, 111350, 2025.

A. Harrison, W. F. Mbasso, I. Dagal, N. H. Alombah, P. Jangir, S. F. Al-Gahtani, and Z. M. S. Elbarbary, “Environmental sensor-less hybrid analytical–machine learning (ESHAML) framework for ultra-fast solar irradiance estimation in climate-sensitive real-time applications: Experimental validation,” Measurement, vol. 257, 118635, 2026.




DOI (PDF): https://doi.org/10.20508/ijrer.v16i2.16973.g9219

Refbacks

  • There are currently no refbacks.


Online ISSN: 1309-0127

Publisher: Gazi University

IJRER is indexed in EI Compendex, SCOPUS, EBSCO, WEB of SCIENCE (Clarivate Analytics)and CrossRef.

IJRER has been indexed in Emerging Sources Citation Index from 2016 in web of science.

WEB of SCIENCE in 2025; 

h=35,

Average citation per item=6.59

Last three Years Impact Factor=(1947+1753+1586)/(146+201+78)=5286/425=12.43

Category Quartile:Q4