The coal burn of the Progress Energy Carolinas unit of Duke Energy (NYSE: DUK) has plunged lately, with a burn of 11.2 million tons during the one-year period October 2010-September 2011 period, against a burn of only 9.3 million tons in the October 2011-September 2012 period.
Those comparative figures are derived in part from a monthly fuel report for September 2012 that Progress Energy Carolinas (PEC) filed Nov. 15 with the North Carolina Utilities Commission, and a report covering the September 2011 burn figures that it filed a year ago.
In the October 2010-September 2011 period, PEC burned 11.2 million tons of coal and took delivery of 12 million tons. During the October 2011-September 2012 period, it took delivery of 9 million tons of coal and burned 9.3 million tons of coal. The fact that in the latest one-year period it burned more than it received is explained by the fact that its coal inventory fell from 2.2 million tons at the start of the October 2011-September 2012 period, to 1.9 million tons at the end.
The report for September 2012 doesn’t offer any narrative explanations, just figures. But various utilities, including new sister utility Duke Energy Carolinas, have also reported sharp drops in coal burn due to factors like low power demand and cheap natural gas that is helping drive much higher gas-fired generation.
These are several PEC coal plants shown with no capacity factors in the October 2011-September 2012 period, which basically denotes plants that have been shut. Facilities in that category are Cape Fear 5-6, Lee 1-3, Robinson 1, Sutton 1-3 and Weatherspoon 1-3.
The capacity factors in the latest 12-month period for the coal units that did run are: Asheville 1, 50%; Asheville 2, 57%; Mayo 1, 49%; Roxboro 1, 46%; Roxboro 2, 70%; Roxboro 3, 55%; and Roxboro 4, 62%. Any reasonably well maintained coal unit should, under full demand situations, achieve a capacity factor of at least 80%, so these coal units obviously didn’t run particularly hard during that period.
On the other hand, PEC burned 85,695,528 MCF of natural gas in the October 2011-September 2012 period, up sharply from 53,926,437 MCF in the prior twelve-month period.
PEC had announced on Sept. 28 that as of Oct. 1 it would officially retire the coal-fired Cape Fear power plant and H.B. Robinson Unit 1, following through on a plan first announced in July. These closures were part of its fleet-modernization program. The closing of older, less-efficient coal plants and replacing them with state-of-the-art natural gas-fueled plants helps ensure continued grid reliability, reduces air emissions and water usage, and offers new economic development opportunities, the company noted.
In addition, PEC retired its coal-fired W.H. Weatherspoon plant near Lumberton, N.C., in 2011, and the H.F. Lee power plant near Goldsboro, N.C., in September. It will close another coal-fired power plant, L.V. Sutton near Wilmington, N.C., in late 2013. Once the retirements are complete, the utility will have retired all of its coal-fired power plants that do not have advanced environmental controls. This represents more than 1,600 MW, or about one-third of its coal fleet.