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With businesses and nations attempting to reduce their reliance on fossil fuels and mitigate their impact on the environment, many are turning to renewable sources of energy.



Eleven million people worked in renewable energy in 2018, according to recent analysis from the International Renewable Energy Agency (IRENA). This represents an increase of 700,000 compared to 2017, when 10.3 million people worked in the sector. Here, CNBC's "Sustainable Energy" takes a look at the top five technologies that employ these clean energy workers, according to IRENA's Renewable Energy and Jobs Annual Review.

Solar heating/cooling — 801,400

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Asia represents a large chunk of the world's solar heating and cooling jobs, with 711,000 people there employed in the sector last year, according to IRENA. The organization also estimated that there were 12,100 solar heating and cooling workers in the U.S. According to the Solar Energy Industries Association (SEIA), solar heating and cooling systems gather the Sun's thermal energy and use it to, "provide hot water, space heating, cooling and pool heating for residential, commercial and industrial applications."

Wind energy — 1.16 million

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More than 1.1 million people worked in wind energy in 2018. IRENA said that 44% of wind power jobs were found in China, with Germany and the U.S. making up the top three.



IRENA said the offshore sector "could be an especially attractive option for leveraging domestic capacity and exploiting synergies with the oil and gas industry."

Hydropower — 2.05 million

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Employing more than 2 million people in 2018, hydropower places third in the list. The International Energy Agency describes hydropower as the planet's biggest source of renewable electricity, with more than 1,200 gigawatts of installed capacity. According to IRENA's report, over 70% of hydropower jobs were in the operations and maintenance sector, while construction and installation contributed 23% of its workforce.



Liquid biofuels — 2.06 million

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IRENA's report found that, worldwide, liquid biofuel jobs increased by an estimated 6% in 2018. Brazil was the biggest employer in this area, boasting 832,000 jobs. Examples of liquid biofuels include ethanol and biodiesel. The U.S. Department of Energy says that ethanol can be produced from a range of plant materials, while biodiesel can be derived from sources such as vegetable oil and animal fats.

Solar photovoltaic — 3.61 million

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