China's electricity consumption growth will accelerate in the second quarter after usage unexpectedly slowed in the first three months of 2013, the China Electricity Council (CEC) said Saturday.

Total electricity consumption is expected to rise between 5.5 percent and 6.5 percent year on year in the first half of the year and pick up further at a pace of 6.5-8.5 percent for the full year, the CEC said in an annual industrial report.

The expected growth would be much faster than the 4.3 percent increase in the first three months, a lower-than-anticipated expansion that marked a slowdown of 2.5 percentage points lower than the same period of last year.

The fall in electricity consumption followed a slowing Chinese economy that expanded only 7.7 percent year on year in the first quarter.

Wang Zhixuan, secretary-general of CEC, told a press conference on Saturday that he expects a mild recovery of the economy beginning in the second quarter and carrying on throughout the year, thus boosting the demand for power.

Wang projected total electricity consumption to reach 2.51-2.53 trillion kilowatts-hours (kwh) for the first half of the year and 5.28-5.38 trillion kwh for 2013.

As demand rebounds, the power supply capability will also grow in the coming three quarters, according to the CEC report.

The CEC estimated that China will add 41 million kilowatts in new installed power generating capacity in the first half and 87 million kilowatts for the full year, empowering the country with the world's largest power generating capacity.

Yet Wang warned of some bad factors affecting the country's power supply. He said climate change and extreme weather will increasingly weigh on the country's power grids.

Some provinces in eastern and northern China are likely to see tight power supply during the peak hours this summer, Wang said, adding reform in the natural gas pricing mechanism will push up costs for those gas-powered units and undermine their electricity generating capacity.