* Implied total oil demand up 5 pct in 2012
* Crude throughput to rise 480,000 bpd
* Nat gas consumption up 16.3 pct; imports to surge
* To complete buildings of SPR tanks under phase-2 (Adds quote, comments on SPR)
By Judy Hua and Chen Aizhu
BEIJING, Feb 9 (Reuters) - China's implied oil demand is likely to grow by a less-than-average 5 percent this year to 9.9 million barrels per day, an industry research group said on Thursday, as a slowdown in economic growth caps fuel consumption.
China is the world's second largest oil consumer and the Institute of Economics and Technology, the research arm of top state energy group CNPC, said average implied oil demand over the last decade was 7.1 percent.
The institute also forecast net imports of crude oil to amount to 266 million tonnes this year, or 5.3 million bpd, the institute said, which would be an increase of 5.9 percent over the official 2011 import figure.
The 2012 implied oil demand growth compared to a 6.8 percent growth last year as calculated by Reuters based on official trade and production figures.
China does not publish actual oil demand data. Implied oil demand is calculated using refinery throughput plus net imports of refined fuel, but strips changes in inventories, which China rarely releases.
"Demand growth in the first half (of 2012) will be slower due to high year-ago bases and a decelerating economy," the research group said in a report.
"But demand growth is likely to rise faster in the second half as inflationary pressure eases and the government's credit policy becomes less tight."
China's annual inflation spiked to 4.5 percent in January as spending jumped during the Chinese Lunar New Year holiday season, breaking a five-month softening trend and forcing a market rethink of policy easing expectations.
The research firm also forecast national crude throughput to rise this year to 470 million tonnes or 9.4 million bpd, an increase of 5.4 percent or about 480,000 bpd compared to 2011.
The throughput increase, which largely echoes a Reuters' poll of top Chinese oil refineries, is bigger than last year's officially reported 4.9-percent gain and will likely boost China's crude oil imports.
The research institute said China would complete adding new crude tanks under its phase-2 strategic petroleum reserve (SPR) plan this year, in line with industry expectations.
The phase-2 plan, officially kicked off in early 2009, has a total capacity of 170 million barrels, but the institute did not say how much of this capacity has already been built and put to use.
China filled its phase-1 SPR tanks, totalling 102 million barrels, by early 2009.
By end of 2011, China's commercial storage for both crude and products amounted to 220 million barrels, the report said. Industry experts estimate that China's current energy stockpiles -- including commercial and strategic reserves -- can cover roughly 40 days of demand.
The report also said China's natural gas consumption will rise 16.3 percent this year to more than 150 billion cubic metres.
China will raise imports of liquefied natural gas (LNG) by more than one-third this year to over 16 million tonnes, or 22 billion cubic metres (bcm). Imports via the central-Asia pipeline will surge two-thirds to 25 bcm, the report said.
China will also add 38.2 million tonnes per year, or 764,000 bpd of new crude refining capacity in 2012, to bring the total refining capacity to 11.6 million bpd.
(tonne=7.3 bbls for crude conversion) (Additional reporting by Su Dan; editing by Miral Fahmy)