Advancing Carbon-Free Generation

Advancing Carbon-Free Generation

May 18,2009

Ken Silverstein
EnergyBiz Insider
Editor-in-Chief

Congress is moving steadily toward carbon constraints. Such emissions are likely to be controlled through a free market system in which carbon credits are traded. In such a world, some utility researchers are saying that a place exists for both new coal generation and older units that can be economically retrofitted to better the environment.

While the older coal-fired plants pale when compared to modern power facilities, the aging plants won't likely be retired anytime soon. Utilities with those plants say that they need the capacity. They also reason that it is cheaper to retrofit them with pollution controls than to replace them altogether -- improvements that can involve either the use of newer supercritical coal units or pending but ultra-clean coal-gasification plants.

"We don't have to shut down old plants," says Bryan Hannegan, vice president of environment and generation for the Electric Power Research Institute. "To get to 80 percent reductions in carbon dioxide emissions by 2050 -- what President Obama is proposing -- we need carbon capture and sequestration. Utilities should be asking what they can do today and how much risk they are willing to take. They need to work with their regulators and stakeholders and push it as hard as they can go."

Hannegan goes on to say that once trading markets are established and the price of a ton of carbon is fully realized, then new coal gasification plants will become economically justifiable. Such plants, which are mostly in the testing stages, scrub the coal before it is combusted thereby avoiding most of the harmful pollutants.

The largest demonstration projects are in Norway, where StatoilHydro is placing one million tons of carbon dioxide per year into a saline aquifer deep in the North Sea, and in Canada, where the carbon dioxide is going into the Weyburn oil field just north of the North Dakota border. Meanwhile, American Electric Power is expected to start building a demonstration project in West Virginia that has the potential to capture and sequester carbon -- a facility modeled after one in Wisconsin that just captures the emission.

Some major companies such as ConocoPhillips, General Electric and Shell Corp. are also working on coal gasification technologies that have the potential to bury carbon.

Power companies contribute 33.3 percent of all CO2 emissions in the United States, according to government stats. The Energy Information Administration is furthermore projecting a 66 percent increase in coal-based power production and a 43 percent increase carbon emissions by 2030 if no pollution controls on such releases are required.

"The technology is on a good trajectory," says Hannegan, who expects carbon capture and sequestration tools to become commercial by 2020. And while he remains convinced of the possibilities, he says that an equally important task is to ensure that public policy encourages such development and that it does not hold developers at risk years into the future for events they could not have possibly foreseen today.

Showing Leadership

The vast majority of coal used today is pulverized, meaning it has been crushed to a fine dust before it is shifted to a furnace and burned. Older coal-fired plants are the least efficient with about 35 percent of the energy input converted to electricity.

But as more power generators opt for supercritical units with higher water-side operating pressures the efficiencies associated with pulverized coal units can increase to 40 percent, or even higher. Considering the tonnage of coal burned each year, those improvements could have a dramatic effect on the environment. Canada-based EPCOR, for example, successfully uses such advanced coal combustion technology.

If the company were starting a new coal plant today it would use coal gasification, says Doug Topping, senior vice president of generation for EPCOR. Efficiencies could then reach as high as 60 percent, although the cost to build would be about $1,200 to $1,600 a kilowatt compared to $900 with conventional coal plants.

"This is where you can expect the industry to be going forward and we expect to be there," says Topping. "We've made a voluntary commitment to reduce our carbon dioxide emissions -- ultimately -- by 50 percent. We will annually take our actions to the regulator for approval."

While green groups are skeptical of coal, many are nonetheless resigned to the fact that it will play an integral role for some time. Fossil fuels, in fact, comprise 80 percent of the global energy mix. Therefore, many of those approach the topic by saying that if coal plants are built, they should be equipped with the latest and greatest technologies.

Great strides are being made. It's now possible to dramatically cut such pollutants as nitrogen oxide and sulfur dioxide, which leads to acid rain. And utilities and researchers alike are trying to figure out ways to capture and trap carbon dioxide.

"The principal environmental benefits associated with coal gasification are significantly lower air pollution emissions in the short term and more cost-efficient CO2 capture and sequestration in the long term," says Brian Ferguson, executive officer for Eastman Chemical Co., in testimony before Congress. "As additional commercial-sized coal gasification plants are built, the competitiveness of this environmentally superior technology should become more evident."

Sustainable alternatives along with modern technologies are more expensive than traditional forms of generation. But with continued research and the subsequent of advanced of technology, carbon-free electricity will become more competitive -- something that will require utilities to stand up and lead the charge.