Introduction: Climate capacity refers to the ability of an ecosystem, community, or system to absorb the impacts of climate change while maintaining its core functions, identity, and structure. It includes adaptive capacity, resistance to climate-related stressors such as extreme weather events, temperature changes, or rising sea levels. Building climate capacity involves enhancing the ability of individuals, organizations, and communities to effectively respond to climate change. Water conservation is a vital component of this process, as water resources are directly impacted by climate changes (Lan, M et al, 2021). Understanding and improving climate capacity helps countries, especially developing nations, prepare for and respond to climate impacts by developing strategies for mitigation and adaptation that are essential for reducing vulnerability and increasing resilience (Pinotti. T et al, 2024).

Capacity building through solar exploitation involves utilizing local skills, resources, and infrastructure to maximize the benefits of solar energy projects. This approach can lead to economic growth, job creation, and improved human health and well-being (Renewable energy benefits, 2025). Solar energy systems produce clean, non-polluting, and sustainable electricity, reducing greenhouse gas emissions and mitigating climate change (J. Boren, 2025). Due to environmental crises and fossil fuel shortages, attention to renewable energy, especially solar energy, has increased. Solar energy reduces air pollution and preserves natural resources.

Materials and Methods: This study focuses on the southern regions of Iran, which include Khuzestan, Fars, Bushehr, Hormozgan, and parts of the southern watershed of Balochistan. The climate characteristics of this region include permanent humidity on the coasts, low precipitation, and high temperatures. The dominant climate is hot and dry, although mountainous areas have different conditions. Data from 98 counties in the study area were analyzed, with a specific focus on the average sunny hours per day. The data were obtained from meteorological stations and satellite data, covering the period from 2000 to 2023. Key metrics included the average daily sunny hours and the Normalized Difference Dust Index (NDDI) to assess air clarity.

The daily sunny hours data were obtained from the Meteorological Organization, and the study area was analyzed by county. Not all counties in the study area have meteorological stations, so the average sunny hours were derived from neighboring stations. The data period covered sunny hours from 2000 to 2023. The clarity of the air was assessed using satellite data and the NDDI index from the MODIS satellite data.

Results and Discussion: The study found that the highest average sunny hours were in the southern and eastern parts of Fars province and the southern part of Sistan and Baluchestan province. This finding is significant both for solar exploitation and for managing thermal comfort in prolonged hot days. Regions with the highest sunny hours also face the challenge of higher energy consumption to maintain thermal comfort.

Cluster analysis using Ward's method identified ten clusters, with Cluster 2 (including counties like Bakhtegan, Estahban, Arsanjan, Sarvestan, Kherameh, Marvdasht, Nikshahr, Shiraz, and Neyriz) scoring the highest in terms of solar exploitation capacity. This cluster exhibited the highest average sunny hours and the highest NDDI values, indicating clear and sunny skies.

Conversely, Cluster 8 (including counties such as Iranshahr, Aghajari, Omidieh, Bavi, Khenj, Owz, Ahvaz, Bastak, Khameer, and Zarindasht) scored the lowest, primarily due to lower average sunny hours and higher dust levels, which hinder solar energy exploitation.

Solar energy potentials in Iran are vast, with estimates of 43,000 MW potential for renewable energy, but only 1,300 MW utilized so far. This study highlights the significant potential for solar energy exploitation in southern Iran, particularly in mountainous regions with clear skies. Advanced technologies, such as TES (Thermal Energy Storage), can further enhance the efficiency and reliability of solar energy systems.

Conclusion: The study concludes that the southern regions of Iran, particularly parts of Fars and Sistan and Baluchestan provinces, have significant potential for solar energy exploitation. The key factors influencing this potential are the number of sunny hours and the clarity of the sky. The cluster analysis highlights that areas with high solar capacity tend to be in mountainous regions with clear skies. The findings suggest that developing strategies for solar energy exploitation in these areas can significantly contribute to climate capacity building and reducing reliance on fossil fuels.

This study also underscores the need for further research and development in solar energy technologies and capacity building to harness the full potential of solar energy in Iran. By leveraging local resources and infrastructure, the country can achieve sustainable economic growth, job creation, and improved quality of life while reducing greenhouse gas emissions and mitigating climate change.

Keywords: Climate Capacity, Solar Energy, Sunny Hours, Southern Iran, Climate Adaptation, NDDI, Renewable Energy, Ward's Method, Cluster Analysis