Since 1987, Wyoming has been ranked a top U.S. producer of coal—satisfying 40% of the country’s electricity needs. Globally, coal itself is forecast to outpace oil as the world’s No. 1 fuel by 2015. Cheap North American natural gas, coupled with regulations, has hurt the domestic market for coal. These facts starkly contrast beliefs of lawmakers like Mead. “The importance of this industry to the country cannot be overstated,” he said.

Researchers at Wyoming’s State Geological Survey (WSGS), citing coal production records dating to 1865, have determined the state, through its resources, has contributed 176 quadrillion Btus to the nation’s energy supply. “This is enough to power the entire nation’s electricity grids for more than eight years,” said Chris Carroll, a WSGS coal geologist. “Our estimates for recoverable reserves show we can continue to produce this valuable resource long into the future, as well as expand into other potential international and economically viable markets.”

Current production data, via historical and other records, also reveals 9.86 billion tons of coal has been mined in Wyoming through Q1 2013, Carroll said. Wyoming’s North Antelope Rochelle and Black Thunder mines alone, for instance, accounted for 20% of U.S. coal production in 2012 tons. Last year, according to Carroll, Wyoming mines produced 401 million tons, worth more than $4 billion.

Despite the difficulties facing the industry, people like Marion Loomis, executive director of the Wyoming Mining Association, are optimistic about the industry in his home state for decades to come. “The industry looks forward to supplying power from Wyoming coal—affordably, reliably—for the next 100 years,” he said.