Duke Energy (NYSE: DUK) on May 19 announced plans to retire its Asheville, N.C., coal-fired power plant in four to five years and modernize its generation and transmission system in western North Carolina and upstate South Carolina – significantly reducing environmental impacts, improving system reliability and minimizing long-term costs to customers.
“We’ve developed an innovative plan that’s a ‘win-win-win’ for consumers, the environment and the economy,” said Lloyd Yates, Duke Energy executive vice president of market solutions and president of the Carolinas region. “With the availability and near record low cost of natural gas, this comprehensive project will transform the energy system in the region to meet the growing needs of our customers and significantly reduce emissions and water use. We’re eager to move ahead quickly on these projects and complete the key components of the plan by the end of 2019.”
The plan’s major components include retiring the 376-MW Asheville coal plant, investing approximately $750 million to build a 650-MW natural gas-fired power plant in its place, and installing solar generation at the site – one of the first combinations of its kind. The Asheville site already has two gas-fired combustion turbines with a combined capacity of 324 MW. This plan would eliminate the coal part of the plant.
The plan also includes investing approximately $320 million to build a transmission substation near Campobello, S.C., and connect it to the Asheville power plant with a new approximately 40-mile, 230-kV transmission line. It also includes upgrading and rebuilding additional electrical infrastructure such as transmission lines and distribution substations.
Electricity demand in Duke Energy Progress‘ Asheville service area has doubled over the last four decades. The region currently must import about 400 MW during peak demand periods to ensure system reliability. The region’s power demand is also forecast to grow by about 15% over the next decade.
Duke Energy’s Asheville coal plant is one of the company’s few “must run” power plants, meaning it must operate to maintain reliability, even when it’s not economical. This results in higher fuel costs that are passed on to North Carolina and South Carolina customers each month in their electric bills. The new gas power plant will be able to rapidly ramp up and down to meet the region’s voltage and power demand needs as they change throughout the day.
Duke touts the gas plant as a cleaner option
The gas plant’s combined-cycle technology will capture and convert exhaust heat into additional electricity, and is considered one of the most efficient power plant designs available. At current natural gas prices, the gas plant would be about 35% less expensive to operate than the existing coal plant, Duke noted. Even with its expected higher operating levels, the gas plant is estimated to have significantly lower environmental impacts than the coal plant, Duke pointed out.
- SO2 is estimated to be reduced by approximately 90% to 95%.
- NOx is estimated to be reduced by approximately 35%.
- Mercury is completely eliminated.
- Water withdrawals are estimated to be reduced by 97%.
- Water discharges are estimated to be reduced by 50%.
- CO2 emissions will be reduced by about 60% on a per-megawatt hour basis, due to the efficiency of the new gas plant and the fact that natural gas burns more cleanly than coal.
Closing the Asheville coal plant and building a gas plant will make it unnecessary to invest in 126 MW of oil-fired generation units, to meet peak demand, and other capital investments that were planned for 2019, Duke noted.
Duke Energy is working with the local natural gas distribution company to upgrade an existing natural gas pipeline to serve the Asheville gas plant with a firm fuel supply.
Duke Energy pointed out that it will continue to move forward with removal of existing coal ash at the site, and permanent closure of the site’s ash basins. That is part of a wider Duke program in the Carolinas to take care of controversial coal ash disposal areas at various coal plants, some of which have been shut in recent years for clean-air reasons.
The new transmission line and related upgrades, required for overall system reliability, will provide a more robust pathway to move additional electricity to the region to efficiently meet growing customer demand.
The power plant and electric transmission projects will create a peak construction workforce of about 800 jobs in the 2017-2019 timeframe, and generate significant local property tax revenues when brought in-service.
Enviro groups say new gas plant is not the answer
The Sierra Club said in a May 19 statement that the Duke announcement marks the 190th coal plant announced for retirement since the beginning of the club’s Beyond Coal campaign.
Environmental groups MountainTrue, the Sierra Club, the Southern Environmental Law Center and the Waterkeeper Alliance said in a May 19 joint statement: “For the last three years the Asheville Beyond Coal Campaign and thousands of individuals have called on Duke Energy to transition our region off of coal. This has been a struggle to protect our health, our families and our communities. It has required tireless effort to pursue a brighter vision for Asheville. We can declare victory in securing closure of the plant, for it means an end is in sight for the air, water, and carbon pollution from this plant, but Duke’s announcement to build new gas is inconsistent with the clean energy vision we have called for.
“While we applaud Duke’s decision to retire the Asheville plant, Duke failed to hear what people wanted in its place. Folks want a bright future that supports clean energy, not a giant gas plant polluting Asheville for another 30 years. North Carolina has the opportunity to be a leader in clean energy generation through aggressive investments in solar power, and Duke Energy must be a partner in that effort – but moves like this deeply undermine the ability to bring online clean, reliable 21st century energy options that will create good jobs right here at home.
“While the proposed solar farm is a step in the right direction, it falls far short of the investment needed to move the region to a clean energy future.
“Additionally, this announcement does nothing to address evidence of unsafe air pollution from the Asheville Plant; under Duke’s proposal, the plant could continue to emit sulfur dioxide at levels that threaten public health until the coal-burning units are retired.
“The retirement of the Asheville Plant is a step in the right direction, but it is a half measure, undermined by continuing reliance on an economically unpredictable and polluting source of power. Duke can do better, and our community deserves better. We will continue to use every tool at our disposal to fight for clean energy solutions for Western North Carolina.”