China electricity output from photovoltaic plants rose 80 percent in the first quarter after the world’s biggest solar power market increased installed capacity.

Solar power generation rose to 21.4 billion kilowatt-hours in the three months ended March 31 from a year earlier, the National Energy Administration said Thursday in a statement on its website. China added 7.21 gigawatts of solar power during the period, boosting its total installed capacity to almost 85 gigawatts, the NEA said.

The power-generation increase comes even as more solar plants stand idle because of congested transmission infrastructure. China idled about 2.3 billion kilowatt-hours of solar power in the first quarter, up from 1.9 billion kilowatt-hours a year earlier, according to the NEA data.

Central and eastern China accounted for about 89 percent of new capacity, the NEA said.