U.S. factories are roaring back from the depths of the recession, cranking out more machinery, vehicles and energy.

Factory production has surged 15 percent above its lows of 2½ years ago and is helping drive the economy’s recovery.

Additional Photos

In this Dec. 14 photo, Ford Focus vehicles move on the assembly line at the Ford Michigan Assembly plant in Wayne, Mich. U.S. factories roared to life in December, creating sharply more goods to meet strong demand for business equipment, materials, vehicles and energy. (AP Photo/Paul Sancya)

A jump in manufacturing output last month coincided with other data suggesting that the economy began 2012 with renewed vigor. Wholesale prices are tame. Demand for U.S. Treasury debt should help keep borrowing costs low. Even homebuilders are more optimistic.

Signs “that manufacturing in the U.S. is gaining global market share appears to be growing, and this could be an important dynamic supporting growth in 2012,” said John Ryding of RDQ Economics.

Manufacturing rose 0.9 percent from November to December, the Federal Reserve said Wednesday. It was the biggest gain since December 2010.

Overall output at the nation’s factories, mines and utilities grew 0.4 percent. Warm weather dampened demand for energy produced by utilities.

Over the past year, factory output has risen 3.7 percent. Factories benefited in particular in the second half of 2011 from several trends: People bought more cars. Businesses spent more on industrial machinery and computers before a tax incentive expired. And companies restocked their supplies after cutting them last summer.

Many economists say manufacturing output should expand further this year, though some expect the pace to slow mainly because of Europe’s debt crisis.

Dan Meckstroth, chief economist at MAPI, a manufacturing research group, said there’s still plenty of pent-up consumer demand for cars. That demand should keep production of cars and auto parts growing.

And high prices for oil, copper and other metals should boost growth in mining and drilling. That would lead to greater demand for drill pipes, large trucks used in mining and other gear, in the United States and overseas.

Another contributor to growth could be construction, which is showing signs of life as builders put up more apartments, office buildings and factories. That means construction firms need more manufactured goods, such as drywall, steel beams, glass and copper wires.

Last year’s growth has also fueled more hiring. Factories added 23,000 jobs in December, the most since July. That helped reduce the unemployment rate to 8.5 percent, the lowest level in nearly three years.

Among the manufacturers faring better is Steris Corp., which makes sterilization equipment and other medical supplies. Hospitals and drug companies are buying more of the company’s products.

Steris, based near Cleveland, says it has added 250 employees in the past 18 months and is still hiring. It has more than 5,000 employees globally, about half of them in the United States.

Steve Norton, a spokesman, said Steris has benefited from being part of a regional cluster of biomedical firms and research facilities. Some manufacturers in the region that once focused on auto parts are now also making components for medical devices, he noted.

“The Midwest continues to be a manufacturing leader,” Norton said.

Still, Europe’s debt crisis has begun to dampen demand for American exports. That trend, should it continue, could slow manufacturing and threaten growth this year.

That hasn’t happened yet.

December’s gains suggest the industry “is still resistant to the apparent slowdown in growth elsewhere, particularly in Europe,” said Paul Ashworth, chief U.S. economist with Capital Economics.

Businesses are starting to see some relief from high energy and food prices, which should benefit consumers later this year.

The producer price index declined 0.1 percent in December, the Labor Department said. The index measures price changes before they reach consumers.

“Core” wholesale prices, which exclude food and energy costs, rose more sharply in December — 0.3 percent. But economists downplayed the increase. They cited temporary factors that had pushed auto prices down in October and November.

Overall, wholesale prices are trending lower. They rose 4.8 percent in December compared with the same month a year ago, reflecting in part higher oil and other commodity prices. Even so, that was the slowest year-over-year increase since January.

Falling prices for oil and agricultural commodities have lowered the cost of food and energy. Gas prices have turned upward in recent months, but economists don’t expect that to worsen inflation this year. That’s because prices will likely be lower than last winter and spring, when political turmoil in North Africa and the Middle East sent prices up.

Lower wholesale costs mean manufacturers and retailers face less pressure to raise prices for consumers to maintain profits. That could keep consumer price inflation in check. Lower inflation also gives the Federal Reserve leeway to keep short-term interest rates low and take other steps, if necessary, to boost the economy.

Borrowing costs are likely to stay low next year, especially if U.S. Treasury debt remains in strong demand around the globe. That’s because high demand for Treasurys drives their yields down. Those lower yields, in turn, help keep interest rates down on other loans throughout the economy.

Foreign holdings of U.S. Treasurys rose in November to a record $4.75 trillion, the Treasury Department said. U.S. government debt is still considered among the safest investments. And it has been in high demand as worries about Europe’s debt crisis have intensified.

The dollar has strengthened in recent weeks, particularly against the euro. A stronger dollar makes imports cheaper and helps keep inflation in check.

In addition, lower rates on long-term Treasury debt tend to drive down mortgage rates. So far, super-low home-loan rates haven’t given much life to the housing market. But they have made U.S. homebuilders slightly less pessimistic.

The National Association of Home Builders/Wells Fargo builder sentiment index rose in January for the fourth straight month, to its highest level since June 2007.

The reading remains far below levels that would suggest builders are optimistic about a turnaround. Homebuilders appear to be drawing optimism from rising interest among would-be buyers — interest that builders hope will lead to higher sales.

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