New, cleaner units advance fossil fleet transition
By replacing older coal-fired generation with new, advanced-technology coal and natural gas plants, Duke Energy is delivering on its promise to deliver cleaner energy from a diverse mix of fuel sources.
Duke Energy’s investment in five new plants (three completed in 2012 and two in progress) totals $9 billion — allowing the company to retire approximately 3,400 megawatts (MW) in older coal units by the end of 2013. That number will grow to nearly 6,300 MW over the next few years. The company has invested another $7.5 billion in plant upgrades at other units to reduce air emissions and improve air quality across our service areas.
All of these fleet modernization investments have reduced our emissions of sulfur dioxide by 83 percent and nitrogen oxides by 64 percent since 2005. About 82 percent of the domestic coal fleet is scrubbed currently, with that approaching nearly 100 percent once upcoming retirements occur.
This work to modernize our fossil plants will help Duke Energy achieve compliance with upcoming environmental regulations. We estimate investing another $5 billion to $6 billion in the next decade to prepare for anticipated new regulations, primarily in the water and waste management areas.
Producing cleaner energy
Duke Energy brought three new, state-of-the-art fossil units on line in late 2012, marking significant milestones in the company’s multiyear effort to transition to higher-efficiency, cleaner generating sources.
Cliffside Steam Station
Cliffside Steam Station Unit 6 in Mooresboro, N.C., provides 825 MW of generation. This new advanced-coal unit employs an innovative combination of air quality controls to remove 99 percent of sulfur dioxide, 90 percent of nitrogen oxides and 90 percent of mercury emissions.
Its high efficiency means it burns less coal per unit of electricity generated than most other coal units in the nation. This unit also has the flexibility to burn a wide range of coals as it reduces emissions. As a result, Duke Energy can purchase less expensive coal and pass those savings on to customers, while also reducing air emissions.
As part of modernizing the entire Cliffside site, Duke Energy also added an emissions “scrubber” to unit 5 and retired four 1940s-era coal units in 2011. With these retirements and upgrades, Cliffside now generates more than twice the electricity it did before, with 80 percent less sulfur dioxide emissions and half the nitrogen oxides and mercury.
H.F. Lee Plant
The 920-MW H.F. Lee Plant near Goldsboro, N.C., features a highly efficient natural gas combined-cycle design. This new facility, along with five combustion turbines at the Wayne County Plant, is now called the H.F. Lee Energy Complex, with a total generation capacity of 1,800 MW. Duke Energy Progress retired three older coal units (totaling 382 MW) and four combustion turbines at the H.F. Lee Plant in fall 2012.
Dan River Combined Cycle Plant
Also newly on line is the Dan River Combined Cycle Plant in Eden, N.C., with 620 MW of natural gas-fueled generation. This facility has more than twice the 276 MW of coal capacity we retired there in spring 2012. Duke Energy also retired all three older combustion turbines at the site in fall 2012.
Natural gas plants like those at H.F. Lee and Dan River have high efficiency and flexibility, while producing significantly fewer emissions than the retired units at those sites. Other relatively new combined-cycle plants in the Carolinas include a 600-MW plant at the Sherwood H. Smith Jr. Energy Complex and the 620-MW Buck Combined Cycle Station, both of which began commercial operation in 2011.
New plants in progress
Construction of a 625-MW natural gas combined-cycle facility continues at the Sutton Plant near Wilmington, N.C., where 575 MW of older coal-fired generation will be retired. This new gas plant is scheduled to be commercially available by the end of 2013.
And start-up testing is under way at the new 618-MW Edwardsport Integrated Gasification Combined Cycle Station in Indiana, scheduled to be commercially available in mid-2013.