The world added 44.7 gigawatts of wind power capacity in 2012, but that wasn’t enough to keep the rate of growth from slowing for the third consecutive year.

In releasing annual wind power totals, the Global Wind Energy Council cited a big drop by China – from 18 GW of new capacity added in 2011 to 13.2 GW brought online in 2012 – in holding the growth rate to just under 19 percent. In 2009, installed capacity had grown by 32 percent. In 2010, it grew 24 percent, and in 2011, 21 percent.

That’s not a great trend, but stepping back a bit things look better: In 10 years, global capacity has gone from 31.1 GW to 282.4 GW. And even in 2012, the GWEC said, so-called “emerging markets,” like Mexico and European nations (Sweden, Romania, Italy and Poland) beyond the traditional wind countries, pitched in with a record 12.4 GW.

“While China paused for breath, both the U.S. and European markets had exceptionally strong years,” Steve Sawyer, secretary general of the GWEC, said in a statement.

In fact, China barely beat out the U.S. in 2012, 13,200 MW to 13,124 MW, according to GWEC data (1,000 MW equals 1 GW). The two countries together provided some 59 percent of the world’s new installed wind energy capacity in 2012.

China overtook the U.S. in 2010 as the country with the most installed wind energy capacity, and as of the end of 2012 had 75.6 GW installed (the U.S. had 60 GW), but its industry is suffering great growing pains.

A Greenpeace report last fall noted that only 76.7 percent of China’s wind power was actually connected to the grid, and that 12 percent of the wind energy produced in regions examined – some 10 billion kilowatt-hours – was curtailed. That is, turned away because the grid couldn’t take it. The government is now being more careful about approving projects, particularly those over 50 megawatts in capacity.

The U.S. industry, despite the record year it had in 2012, is hardly humming along smoothly itself. The 2012 record only happened because companies, fearing the end-of-year expiration of eligibility for the production tax credit, squeezed in every new project they could. Nobody expects 2013 to deliver anywhere near the total 2012 did, despite the fact the PTC was eventually extended.

Then there’s offshore wind, where the U.S. is trying to gear up but continues to register a big, fat zero. Although more costly to develop, many analysts believe offshore has better long-term potential than land-based wind, with better wind resources and fewer conflicts. There, the United Kingdom is the leader; it brought 854 MW of offshore wind capacity online in 2012, driving its total to 2,093 MW. No other country has yet to reach 1,000 MW.

The Global Wind Energy Council’s “Global Wind Statistics 2012″ document is available online as a PDF.