An estimated US$400 billion will be allocated to solar energy this year, the International Energy Agency (IEA) said on Thursday in its annual world energy investment report.

"About $2.8 trillion is set to be invested globally in energy in 2023, of which more than $1.7 trillion is expected to go to clean technologies — including renewables, electric vehicles, nuclear power, grids, storage, low-emissions fuels, efficiency improvements and heat pumps," the Paris-based agency reported.

Clean energy investment surpasses the estimated $1 trillion allocated to fossil fuels, which includes coal, gas and oil. In the past, the $2 trillion annual energy investment was evenly divided between fossil fuels and clean technologies.

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