Coal no longer king in TVA region as more gas-fired plants used to generate electricity

Oct 8 - McClatchy-Tribune Regional News - Tom Charlier The Commercial Appeal, Memphis, Tenn.

While TVA's half-century-old Allen Fossil Plant in Memphis continued consuming piles of coal to make electricity, agency officials gathered on the other end of the state last week to dedicate a sleek, $775 million facility that represents a quantum shift in how the Mid-South gets its power.

With the new John Sevier Combined Cycle plant near Rogersville, Tenn. -- and several other recently added facilities burning natural gas -- the Tennessee Valley Authority now is producing only one-third of its power with coal-fired generating units. That's a sharp decline from fiscal 2011, when coal-fired boilers produced 52 percent of TVA's power, and it's the first time in decades that coal hasn't fueled the majority of the electricity generated by the agency.

The agency's shift away from coal has been part of a national trend driven largely by the abundance of cheap natural gas extracted from shale through the process of hydraulic fracturing, better known as "fracking." Utilities also have been turning to cleaner-burning gas amid increasingly stringent air-pollution standards targeting emissions from coal units.

During the just-completed 2012 fiscal year, TVA's consumption of gas shot up 70 percent, while its use of coal dropped 30 percent. Gas accounted for about one-fifth of TVA's power, up from less than 1 percent in 2007, agency officials said. Nuclear plants generated one-third of the agency's electricity, with the remainder coming from hydroelectric dams and renewable sources.

"What we're trying to achieve, from a corporate standpoint, is a good, diverse mix of energy sources that we can adjust as the market forces change," said Bob Dalrymple, vice president of gas operations for TVA. He noted that price-wise, coal and gas "are reasonably competitive with one another."

If anything, the fuel switch should only accelerate. TVA during the past two years has announced plans to retire 18 of its 59 coal-fired units by 2017. At the same time, the agency is studying whether to build another gas plant near its Allen facility in southwest Memphis.

Nationwide, utilities plan to idle 8.5 percent of their coal-fired generating capacity by 2016, according to the U.S. Energy Information Administration.

The move toward gas also could be difficult to reverse because of the infrastructure of pipelines and other equipment it prompted. The John Sevier plant, for instance, required the construction of an 8.5-mile, 24-inch-diameter pipeline to deliver the maximum 150 million cubic feet of gas burned daily there.

The 880-megawatt plant, which began operating in April, can generate enough power for about 500,000 homes. It joins other gas facilities recently built, acquired or leased by TVA, including ones in Southaven and near Brownsville, Tenn.

Although they prefer renewable energy to a fossil fuel such as gas, environmentalists generally have welcomed the change. They note that pollution from coal-fired plants contributes to such problems as climate change, urban smog, particulate haze and mercury deposition. Gas facilities, by comparison, emit 40 percent less total pollution and roughly half the amount of greenhouse gases associated with global warming.

"We're very happy to see them (TVA) retire coal plants and reduce their greenhouse emissions," said John D. Wilson, research director for the Knoxville-based Southern Alliance for Clean Energy.

As a result of the switch to gas, the U.S. slashed its emissions of carbon dioxide, a greenhouse gas, by 7.7 percent between 2006 and 2011, a reduction larger than that of any other nation, according to a recent report by the International Energy Agency.

Wilson also said gas facilities are better suited to energy-conservation efforts than coal units, which are difficult to shut down and must be kept running at night.

But he cautioned that gas shouldn't be viewed as a long-term solution to the region's or nation's energy needs. "The biggest drawback in the long run is price volatility," Wilson said.

That point is emphasized by coal industry officials, who point out that nearly 30 percent of the world's coal reserves are found in the U.S. Industry leaders blame what they call regulatory excesses by the Environmental Protection Agency for helping to drive the move away from coal.

"It's the most affordable energy resource over the long term," said Carol Raulston, senior vice president of communications for the National Mining Association.