Japan is expected to become the world's largest solar energy market this year, with the installation of new solar power systems more than doubling capacity, a recent report by a U.S. research firm says.

The domestic solar power market is forecast to reach $19.8 billion (¥1.91 trillion) in 2013, surpassing Germany, which was the biggest market from 2009 to 2012, according to the report by IHS Inc.

An estimated 5.3 gigawatts of generation capacity will be added this year, supplying output roughly equivalent to five nuclear reactors.