China's power generation picked up sharply to climb for a sixth month in September and crude steel output rose at its quickest pace this year as Beijing boosted investment in infrastructure, although analysts see slower growth ahead.

Refinery crude throughput, however, dipped in September from a year ago as a number of refineries are still in the middle of overhauls.

Beijing rolled out targeted policy measures in July to support its economy -- including greater investment in urban infrastructure, power lines and public services -- after nine straight quarters of slower growth and a credit crunch sparked worries of a hard-landing.

The policies have paid off, with China's annual economic growth quickening to 7.8 percent in July to September from 7.5 percent in the previous three months, the fastest growth this year, official data showed on Friday.

Still, analysts said the economic outlook remains murky and China's commodities consumption could slow in the fourth quarter due to seasonal factors, while Beijing may move again to engineer slower growth if it becomes concerned about an over-heated property market.

"Even though the headline figures are strong, the month-on-month recent industrial output number has showed that growth momentum is slipping in recent months," said Graeme Train, analyst at Macquarie Commodities Research.

"We should see some slowdown in the fourth quarter but it won't be anything dramatic since the economy is fairly well-balanced and overall inventories are quite low."

Electricity output in the world's second-biggest economy rose 8.2 percent to 431 billion kilowatt hours (kWh) in September, data from the National Bureau of Statistics showed. It was down 13.6 percent from the preceding month as cooler weather reduced power demand for air-conditioning.

China's power consumption is often seen as one of the indicators of the strength of its economy and usage has climbed 7.2 percent in the first nine months of 2013 from a year ago.

Steel output from the world's top iron ore consumer, jumped 11 percent from a year ago to 65.42 million tonnes, the highest growth this year.

On a daily basis, China's average daily crude steel output rose 2 percent to 2.181 million tonnes in September from the preceeding month and was the third-highest on record, as improved orders encouraged mills to lift production.

Looking ahead, however, steelmakers are expected to trim production modestly in the fourth quarter, since orders typically fall in winter as construction activities slow.

Separately, China's refinery crude throughput fell 1.2 percent in September from a year ago to about 9.4 million barrels per day (bpd). Total crude oil processed for the month was 38.65 million tonnes.