Iran has met just one-fifth of its renewable capacity installation target for the five-year period between 2016 and 2021, also because the U.S. sanctions imposed in 2018 significantly slowed down clean energy projects, Tehran Times reports.

Data from the International Energy Agency (IEA) shows that as of 2019, most of Iran’s electricity generation came from natural gas, followed by oil, with hydropower a distant third, and nuclear power—generated by the only nuclear power plant in the country, Bushehr—an even more distant fourth.

Renewable energy, including hydropower, accounts for only 7 percent of Iran’s power generation, compared to a 90-percent share for natural gas, according to Tehran Times. Iran’s five-year development plan 2016-2021 envisaged the Islamic Republic boosting its renewable capacity by 5,000 megawatts (MW). In 2021, the final year of the plan, Iran has achieved only one-fifth of this.

In addition, Iran was looking to become a regional hub of energy over the past decade.

However, foreign companies that returned to Iran after the 2015 nuclear deal backed off projects after the U.S. re-imposed sanctions on Tehran in 2018.

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“Lack of financial resources and problems that we put in the way of investors are two important factors preventing the development of renewable energy and reducing the acceptance for investment in this sector,” Tehran Times quoted the vice-chairman of Iran Electrical Industry Syndicate (IEIS), Payam Baqeri, as saying.

Iran has installed 800 MW of renewables over the past five years. This year, it also suffers from power shortages as consumption soars, while power generation has declined.

Earlier this year, Iran banned air conditioning in Tehran’s state agencies as the country looks to save electricity consumption and prioritize electricity supply to homes and hospitals. The government is looking to prioritize electricity supply to residential areas and hospitals after Iran’s hydropower generation slumped this year because of a lack of rainfall.