Energy-related carbon emissions dropped to their lowest level since 1994 in 2012 because of natural gas, the Energy Information Administration said today.

Lower natural gas prices meant more natural gas production and less coal generation, a shift from the most carbon-intensive fossil fuel to the least, the EIA said.

At the same time competition in the private sector is lowering emissions, the EPA is taking a different approach to the same end, by killing the coal industry with a flood of costly regulations. That drives up the cost of coal, which traditionally has been cheaper than natural gas.

A new Duke University study found the cost of complying with new EPA air standards would make almost two-thirds of the nation’s coal plants at least as expensive to run as natural gas-powered plants.

“Because of the cost of upgrading plants to meet the EPA’s pending emissions regulations and its stricter enforcement of current regulations, natural gas plants would become cost-competitive with a majority of coal plants — even if natural gas becomes more than four times as expensive as coal,” said lead author Lincoln Pratson in a statement today.

The EPA’s constant push for lower emissions is making the coal industry economically vulnerable, the Duke study said. Even with a big jump in gas prices, the rules will make coal more costly.

“The regulations would make 65 percent of coal plants nationwide as expensive as natural gas, even if gas prices rise significantly,” the study said.

Meanwhile, an increase in shale gas fracking has caused the lower natural gas prices, according to the Duke study.