Jan. 17 (Bloomberg) -- China’s power-production growth fell in 2011, a trend that may continue in 2012 as the world’s largest energy consumer is expected to slow its economic expansion.

Electricity generation climbed 12 percent to 4.6 trillion kilowatt-hours, down from an increase of 13 percent in 2010, according to data released today by the Beijing-based National Bureau of Statistics. Output rose 9.7 percent in December to 403.8 billion kilowatt-hours.

China’s economy expanded at the slowest pace in more than two years in the last quarter of 2011 as export demand moderated and the government’s efforts to curb inflation cooled growth. The nation will face a “difficult and complex” 2012, Ma Jiantang, head of the Bureau said today.

“We expect power-production growth to slow to around 8.7 percent in 2012 amid slowing economic expansion,” Peter Yao, an analyst at Bank of China International Holdings Ltd., said by phone from Hong Kong. “Electricity-demand growth in the first quarter will drop to around 5 percent due to a high base in the same period of 2011.”

China had a power shortage of as much as 30 gigawatts in January last year and as much as 25 gigawatts in the summer amid “tight” coal supplies and reduced hydropwer output, the National Development and Reform Commission said on its website today.

The nation had the lowest rainfall in 60 years in 2011, the NDRC, the nation’s top economic planner, said in a separate report. Hydropower output fell 5.5 percent to 620.5 billion kilowatt-hours, it said.

Power-output capacity will rise by 70 gigawatts this year, compared with last year’s increase of 90 gigawatts, the National Energy Administration said Jan. 10. China’s investment in the power industry will drop this year from 2011’s 739.3 billion yuan because of weaker demand and a slowing economy, the official Xinhua News Agency reported.