President Obama said Tuesday Congress\' failure to extend wind-energy tax credits by the end of the year could slow growth in the field and jeopardize jobs. Speaking at a campaign stop in Oskaloosa, Iowa, he noted that wind power generates about 20 percent of Iowa\'s electrical power, The Wall Street Journal reported Tuesday. He also said, of Republican presumptive candidate Mitt Romney\'s derisive comments about alternative energy, \"If he really wants to learn something about wind energy, Iowa, all he has to do is pay attention to what you\'ve been doing,\" adding that \"My opponent wants to end tax credits for wind energy producers. He\'s said new sources of energy like these are imaginary.\" Making reference to vice presidential candidate Paul Ryan, Obama said, \"His running mate calls them a fad,\" the Washington newspaper The Hill reported. The Obama campaign Tuesday was praising a report issued Tuesday by the U.S. Department of Energy mentioning strong growth in the U.S. wind energy market and dramatic increases in electrical production. The report highlighted advances in the U.S. share of the world\'s clean energy and the growth of thousands of jobs in the wind energy field, a statement from the Department of Energy said. It quoted statistics from the 2011 Wind Technologies Market Report, which said the U.S. remained one of the world\'s largest and fastest-growing wind markets in 2011, with wind power accounting for 32 percent of all new electric capacity additions in the country, accounting for $14 billion in new investment. The energy sector employs 75,000 in the United States, it said. \"The wind industry employs tens of thousands of American workers and has played a key role in helping to more than double wind power over four years,\" said Energy Secretary Steven Chu in the statement.