Natural gas-fired combined-cycle units, which have emerged as perhaps the most important elements of utility and independent power generation fleets, have been costing less than was initially expected to build, and per-kW costs of less than $1,000/kW of installed capacity have become common. Duke Energy Progress said Tuesday that the final cost of its 625-MW Sutton combined-cycle project near Wilmington, North Carolina, was $551 million, or about $882/kW of installed capacity, about 18% less than the company’s original $671 million estimate, or a per-kW cost of about $1,073. Duke Energy spokeswoman Lisa Parrish said DEP and its sister utilities have built six gas-fired units over the last five years. “All have come in under budget,” she said. “As we begin to build two new natural [gas-fired] facilities in the Carolinas, we will take advantage of efficiencies and best practices we’ve learned.” Parrish said the project costs include associated transmission […]