Sun may be our main energy source by 2050: IEA

Solar power could trump alternatives like fossil fuels, wind, hydro and nuclear to be the world's largest source of electricity by 2050, according to a prominent energy watchdog.

The International Energy Agency (IEA), which is best known for its monthly oil updates, published two reports on Monday detailing how greater use of solar energy could radically cut the need to use polluting carbon dioxide. The Paris-based agency said that if countries embraced solar energy, carbon dioxide emissions could be cut by more than 6 billion tons per year by 2050.

By the middle of the century, solar photovoltaic systems and solar thermal electricity combined could potentially have total capacity of 4,600 gigawatts, the IEA forecast. This compares to just 154 gigawatts in the early part of 2014.

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Some countries already use a diverse mix of energy and have stringent goals to reduce carbon dioxide emissions to negate the effects of climate change.

Teams gather for the Department of Energy's Solar Decathlon competition.
Source: Department of Energy | Flickr
Teams gather for the Department of Energy's Solar Decathlon competition.

Earlier this month, government heads and business leaders attended a United Nations summit in New York on climate change, and discussed "bold new actions" to tackle the issue. Plus, the European Union aims to cut emissions by 2020 to 20 percent below levels seen in 1990.

In its reports, the IEA detailed how governments should set about reforming energy policy—and some pitfalls to avoid. It called for "clear, credible and consistent" signals from policy makers on solar power, in order to lower deployment risks for investors and inspire confidence.

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"Where there is a record of policy incoherence, confusing signals or stop-and-go policy cycles, investors end up paying more for their investment, consumers pays more for their energy, and some projects that are needed simply will not go ahead," IEA Executive Director Maria Van der Hoeven said in a press release about the reports on Monday.

Huge solar power uptake ahead: Pro
Huge solar power uptake ahead: Pro   

Of the two forms of solar energy discussed by the IEA, solar photovoltaic systems are probably the most widely known, in the form of the solar panels that some homeowners install on their roofs. The could generate up to 16 percent of the world's electricity by 2050, according to the IEA, with China leading the way as the price of panels continues to fall.

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Solar thermal electricity, meanwhile, works by focusing the sun's light energy and converting it into heat to create steam that drives a turbine. The could provide 11 percent of the world's energy by 2050, according to the IEA.

Warren Buffett is one high-profile investor that is betting big on solar technology, among other energy investments. Buffett said this June at the Edison Electric Institute annual conference that his company was ready to double its $15 billion commitment to wind and solar power.

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