تغییر اقلیم و آینده برق‌آبی در ایران: چالش‌ها، فرصت‌ها و چشم‌انداز توسعه انرژی‌های خورشیدی و بادی

Objective: This study aims to assess the vulnerability of Iran’s hydropower dams to climate change impacts and to investigate the potential and feasibility of their gradual replacement with renewable energy sources, particularly solar and wind.
Method: This research employed a narrative review and analytical approach by examining the existing literature, technical reports, and climate change scenarios. The study evaluated the impacts of climate change on Iran’s hydropower generation, assessed the potential for solar and wind energy development, and analyzed international experiences in integrating renewable energy resources into power systems.
Findings: The results indicate that, under different climate change scenarios, Iran’s hydropower generation is projected to decline by 9% to 91%, reducing its share of the country's total electricity generation from approximately 15% to less than 8%. In contrast, with nearly 300 sunny days per year, Iran possesses substantial renewable energy potential, including more than 56.5 GW of solar power capacity and approximately 20,443 GWh of wind energy potential. Furthermore, international experiences demonstrate that integrating hydropower plants with solar and wind energy systems can mitigate the risks associated with drought and climate variability. Nevertheless, implementing this approach in Iran faces significant economic, technical, regulatory, and social challenges.
Conclusion: Diversifying Iran’s energy portfolio through the expansion of renewable energy resources, reforming support policies and subsidy mechanisms, removing investment barriers, and promoting integrated hydro–solar–wind energy systems can provide an effective strategy for enhancing energy security and reducing the vulnerability of the electricity sector to climate change.
 
Introduction
Hydropower is one of the world's most important renewable energy sources, playing a vital role in electricity generation while reducing dependence on fossil fuels and greenhouse gas emissions. Owing to its high efficiency and operational flexibility, it contributes significantly to power system reliability. However, because hydropower depends directly on water availability, it is highly vulnerable to changes in precipitation, river discharge, and reservoir storage. As climate change intensifies, maintaining the long-term sustainability of hydropower systems has become an increasing challenge.
Iran is among the countries where climate change has aggravated water scarcity through rising temperatures, prolonged droughts, and declining precipitation. These changes have reduced river flows and reservoir storage, leading to lower hydropower generation and increasing pressure on conventional electricity production. At the same time, Iran possesses abundant solar and wind resources that provide valuable opportunities to diversify the national energy mix and strengthen energy security. Integrating hydropower with solar and wind energy therefore represents a promising strategy for improving the resilience of the electricity sector under changing climatic conditions.
Although numerous studies have investigated the impacts of climate change on hydropower or evaluated renewable energy resources, these issues have generally been addressed separately. An integrated assessment that links hydropower vulnerability with the potential of solar and wind energy, while considering the technical, economic, and policy challenges of the energy transition, remains limited, particularly in the context of Iran.
Accordingly, this review examines the impacts of climate change on Iran's hydropower sector and evaluates the potential of solar and wind energy to complement hydropower and enhance the resilience of the national electricity system. The review addresses the following research questions:

How has climate change affected the performance of hydropower systems in Iran?
To what extent have declining river flows and reservoir storage reduced hydropower generation?
What opportunities do solar and wind energy offer for complementing or partially replacing hydropower under Iran's climatic conditions?
What technical, economic, institutional, and policy challenges must be addressed to facilitate this energy transition?

Unlike previous studies that have generally focused on either hydropower vulnerability or renewable energy development in isolation, this review adopts an integrated perspective by linking climate-induced reductions in hydropower generation to the development potential of solar and wind energy. By synthesizing recent scientific evidence, evaluating renewable energy opportunities, and discussing implementation challenges in the Iranian context, this study provides a comprehensive framework to support future research and inform energy and water management policies aimed at strengthening climate resilience and long-term energy security.
 
Method
This study employs a structured narrative review based on a systematic literature search and qualitative synthesis. The methodology was designed to identify, evaluate, and integrate the existing body of knowledge on the impacts of climate change on hydropower systems and the potential role of solar and wind energy in enhancing energy resilience in Iran.
 
(a) Literature Search
A comprehensive literature search was conducted using major international scientific databases, including Scopus, Web of Science, ScienceDirect, and Google Scholar, together with relevant Persian databases such as Magiran and the Scientific Information Database (SID). The search covered publications from 2000 to 2025, with particular emphasis on studies published during the last decade.
The search strategy combined keywords related to climate change, hydropower, renewable energy, solar energy, wind energy, water–energy nexus, and Iran using appropriate Boolean operators.
 
(b) Study Selection
Studies were selected according to predefined eligibility criteria. Publications were included if they:

investigated the impacts of climate change on hydropower systems;
evaluated the potential of solar or wind energy, particularly in arid and semi-arid regions;
examined water–energy interactions in Iran or regions with comparable climatic conditions; or
were published in peer-reviewed journals or issued as official reports by recognized national or international organizations.

Studies focusing exclusively on engineering aspects of dams without considering climate impacts, lacking sufficient methodological information, or published in non-peer-reviewed sources were excluded.
The literature selection process consisted of three sequential stages: (1) title and abstract screening, (2) full-text assessment, and (3) final eligibility evaluation. After removing irrelevant publications, 31 international studies and 12 Persian-language reports and peer-reviewed publications were included in the final review.
 
(c) Data Analysis
Because the selected studies employed diverse methodologies—including climate models, hydrological simulations, and energy system analyses—a quantitative meta-analysis was not appropriate. Instead, a qualitative thematic synthesis was conducted to identify common findings, differences, and research gaps. The analysis focused on five major themes:

Climate change impacts on hydropower performance;
Changes in river discharge and reservoir storage in Iran;
Solar and wind energy potential under Iranian climatic conditions;
International experiences in integrating hydropower with renewable energy; and
Technical, economic, institutional, and policy challenges associated with the energy transition.

 
(d) Study Limitations
Several limitations should be acknowledged. First, relatively few studies have simultaneously examined hydropower vulnerability and renewable energy transition within the Iranian context, limiting the availability of integrated evidence. Second, publicly available data on recent hydropower generation in Iran remain limited, requiring the use of official national reports where appropriate. Finally, some international studies reviewed were conducted under climatic and socio-economic conditions different from those of Iran; therefore, their findings should be interpreted cautiously when applied to the Iranian context.
 
Results
(i) Climate Change Has Significantly Reduced Hydropower Performance in Iran
The reviewed studies consistently demonstrate that climate change has substantially affected the performance of Iran's hydropower sector through declining precipitation, reduced river discharge, and lower reservoir storage. Across different climate scenarios, hydropower generation is projected to decrease by approximately 9% to 91%, resulting in a considerable decline in the contribution of hydropower to the national electricity supply.
The magnitude of these impacts varies among river basins and climate scenarios. Studies conducted on the Dez, Karun, and Marun basins consistently report reductions in reservoir inflow, hydropower generation, and system reliability under future climate conditions. In addition to climatic factors, human-induced pressures on water resources further intensify these reductions. Collectively, the reviewed evidence indicates that both climate change and increasing water demand have considerably reduced the operational reliability of hydropower plants in Iran. [4-10]
 
(ii) Solar and Wind Energy Offer Significant Opportunities for Energy Diversification
The reviewed literature highlights Iran's substantial renewable energy potential, particularly for solar and wind power development. Owing to extensive solar radiation and favorable climatic conditions, large-scale deployment of photovoltaic systems could significantly compensate for the decline in hydropower generation. Likewise, several regions, especially in northwestern Iran, possess considerable wind energy resources suitable for utility-scale electricity production.
National development plans also emphasize expanding renewable electricity capacity over the coming years. Moreover, international experiences demonstrate that integrating hydropower with solar and wind energy can improve power system flexibility, reduce vulnerability to drought, and enhance long-term energy security. Hybrid renewable systems have therefore emerged as an effective strategy for increasing the resilience of electricity systems under climate change. [11-16].
 
(iii) Major Challenges Limit the Transition toward Renewable Energy
Despite the significant renewable energy potential, several barriers continue to hinder the large-scale deployment of solar and wind power in Iran. Economic constraints—including investment limitations, high initial costs, and inadequate financial incentives—remain among the most important obstacles. Technical challenges such as the limited development of smart grids, electricity storage systems, and reduced photovoltaic efficiency under dust storms further restrict renewable energy expansion.
Institutional and policy-related barriers, including fossil fuel subsidies, regulatory instability, and insufficient long-term planning, also slow the transition process. Furthermore, limited public awareness and social acceptance create additional challenges for renewable energy projects in some regions.
Overall, the reviewed evidence suggests that although Iran possesses abundant renewable energy resources, realizing this potential requires coordinated technological, economic, institutional, and policy reforms. Without addressing these barriers, renewable energy development may not be sufficient to compensate for the projected decline in hydropower generation under future climate conditions. [1-3].
 
Conclusion
This review examined the impacts of climate change on Iran's hydropower sector and the potential of solar and wind energy to strengthen the country's energy resilience. The reviewed evidence indicates that declining precipitation, rising temperatures, and reduced river discharge have significantly weakened hydropower generation, with future projections suggesting substantial reductions in electricity production and a declining contribution of hydropower to the national energy mix.
At the same time, Iran possesses considerable solar and wind energy resources that could complement hydropower and improve energy security under changing climatic conditions. International experience shows that integrating hydropower with renewable energy systems offers a practical pathway for reducing climate-related risks and enhancing the flexibility of electricity systems.
However, achieving this transition will require coordinated policy reforms, investment incentives, modernization of electricity infrastructure, and the gradual removal of institutional and economic barriers. Overall, this review suggests that strengthening Iran's energy security depends not on replacing hydropower entirely, but on developing an integrated and diversified renewable energy system in which hydropower, solar, and wind energy operate as complementary resources. Future research should focus on optimizing hybrid renewable energy systems under future climate scenarios.