CB&I at Work on Prototype of Emissionless Natural Gas Power Plant
A first-of-its-kind natural-gas-fired power plant that will emit no greenhouse gases is now under construction near Houston, and its commercialization is being financed in part by engineering-procurement-construction contractor CB&I, with the hope CB&I will be the go-to builder for larger versions of the plant in the future.
CB&I broke ground on the 50-MW demonstration project in La Porte, Texas, on March 9 and is expected to complete the facility in 2017. The EPC contractor’s collaborators on the project are Exelon Generation, the independent power subsidiary of Exelon Corp.; NET Power, a Durham, N.C.-based company responsible for the commercialization of the project’s Allam Cycle technology; and 8 River Capital, which developed the technology.
Walker Dimmig, spokesman for NET Power, said the technology’s “oxy-fuel, supercritical carbon-dioxide power cycle” will burn natural gas with oxygen, rather than air, and use high-pressure CO2, rather than steam, to drive a turbine. As a result, he said, the demonstration plant—and the 295-MW commercial-scale version the development team already is discussing with potential clients—will produce only electricity, water and pipeline-ready CO2 while operating as efficiently as advanced combined-cycle units that have become the industry norm. The captured CO2 will be used in enhanced oil recovery or other industrial processes.
Announcing the March 9 groundbreaking, NET Power said the $140-million development program—“which not only includes demonstration-plant design and construction but also ongoing technology advancement, a full testing-and-operations program, and commercial product development—is being funded by a combination of cash and in-kind contributions from Exelon and CB&I.”
CB&I declined to comment, referring questions about the project to NET Power. However, during CB&I’s Feb. 9 “Investor Day” presentation to Wall Street analysts, CB&I President and CEO Philip Asherman, called the NET Power project a “strategic investment” for the company.
During the same presentation, Daniel McCarthy, executive vice president and group president for technology, said the technology employed at the NET Power project “will support our future growth … because [the technology] can eliminate CO2 emissions from fossil-fuel generation … [We] anticipate that NET Power will become the new standard for power generation.”
Dimmig said the primary purpose of the demonstration plant “isn’t to develop the most efficient, cost-effective unit to operate at 50 MW but, rather, to validate key aspects of the Allam Cycle for 295-MW commercial plant development, such as plant controls, operational capabilities and performance.”
He said NET Power believes the Allam Cycle process “can produce power at a cost that is competitive with a conventional combined-cycle plant that does not capture any CO2—and that is one of the key aspects we seek to confirm with this demonstration unit.”
Asked about the complexity of the construction project just getting underway, Dimmig said, “Given this plant is a first-of-a-kind, it is important to ensure all of the different teams and disciplines on site are well coordinated in a new environment. We have very competent teams with great experience building power and chemical plants, though, and this project, in many ways, will be no different than those.”
Dimmig noted that the La Porte project “will require many of the same skilled craftspeople—pipefitters, pipe welders, et cetera,” as the many petrochemical, natural-gas liquefaction and other complicated projects now being built along the Gulf Coast.” He said that, while there has been “strong demand for this type of labor in the region, that isn’t an impediment to the project.”
Fossil-fired power plants with reduced emissions of CO2 are expected to benefit from the Environmental Protection Agency’s Clean Power Plan, which calls for the power sector to reduce, by 2030, its CO2 emissions by 32% below 2005 levels.
Dimmig said that, while NET Power believes its commercial-scale plant “will be able to compete with existing technologies in the market on its own merit, without having to rely on CO2 policies and regulations such as the Clean Power Plan,” efforts to rein in CO2 emissions “will certainly create even greater market incentives to adopt that technology.”
Dimmig noted, finally, that NET Power is “actively engaged” with several potential customers for commercial-scale Allam Cycle units. “The timeline for developing the first commercial plants” will “follow very closely on the heels of the demonstration plant,” he said.
Also near Houston, a consortium of Kiewit subsidiary The Industrial Co. and Mitsubishi Heavy Industries America for several months has been building the Petra Nova Carbon Capture project at NRG Energy’s 610-MW, coal-fired W.A. Parish Unit 8, in Fort Bend County, Texas.
NRG spokesman David Knox said the project will use an amine-based process to remove 90% of the carbon dioxide from a roughly 40% portion of the flue-gas emissions of the Parish unit; the emissions volume is equivalent to the emissions from a 240-MW coal unit. The captured CO2 will be compressed and delivered via a new, 82-mile pipeline to a mature oil field south of Houston, where the CO2 will be used in enhanced oil recovery.
Bob Wolosyn, TIC project director, said, “With any major industrial-sized project, there are intricate components that can lend themselves to complications.” He said the project was designed by “four engineering companies in three countries …Coordination between the engineering groups was paramount to the success of the project.”
Petra Nova is currently on schedule and on budget, Wolosyn said. “All engineering was completed December 2015, and all major mechanical equipment has been procured and is onsite and installed. Construction is now 75% complete and the construction forces are beginning the process of walking down systems and turning systems over to start up.”