Construction on a $1 billion commercial-scale carbon capture and storage (CCS) system—one of the world’s largest to use post-combustion capture technology—began this July at NRG Energy’s W.A. Parish Unit 8 near Houston. The facility is expected to be operational by the end of 2016.
Formerly known as the NRG Energy Parish CCS Project, it is expected to capture about 1.6 million tons per annum (Mtpa) of carbon dioxide (CO2) from a 240-MW–equivalent portion of the flue gas from Unit 8 (Figure 3). The CO2 will then be compressed and piped through an 82-mile-long pipeline to the West Ranch oil field for enhanced oil recovery (EOR).
The project received a financial boost this July as JX Nippon Oil and Gas Exploration Ltd. bought a 50% stake in NRG Energy subsidiary Petra Nova Holdings LLC. The companies now also each own a 25% interest in the oil field along with Hilcorp Energy Co. EOR could boost oil production at the field from around 500 barrels per day to about 15,000 barrels per day, NRG Energy said.
The project will use the KM-CDR Process developed jointly by Mitsubishi Heavy Industries (MHI) and Kansai Electric Power Co. MHI has since 2006 conducted small-scale (10 metric tons per day [mtpd]) demonstration testing for CO2 capture from coal-fired flue gas with J-POWER. In December 2013, it wrapped up a three-year 500-mtpd capture demonstration test at Alabama Power’s Plant Barry. By comparison, the Petra Nova project will have a CO2 capture capacity of 4,776 mtpd.
The Petra Nova project in 2009 received $167 million in financing under the third round of the cost-shared Clean Coal Power Initiative, of which about $7 million has been received in the initial design and engineering phase, NRG Energy said. The project will also rely on loans of $250 million from the Japan Bank for International Cooperation and Mizuho Bank Ltd., backed by Nippon Export and Investment Insurance. NRG and JX Nippon are each expected to contribute $300 million.
The world’s only other large-scale post-combustion capture project for power generation is being built by SaskPower, an entity owned solely by the Saskatchewan government, at the 139-MW Unit 3 of the Boundary Dam coal-fired power plant near Estevan. That project, whose anticipated carbon capture start date was July 2014, uses an amine absorption process designed by Shell Global Canosolv.
CO2 from the Boundary Dam project, an estimated 1 Mtpa, will be used primarily for EOR at the Weyburn Oil Unit and will supplement the existing CO2 supply to the Weyburn–Midale fields delivered by the 205-mile Souris Valley pipeline from the Great Plains Synfuel gasification facility in North Dakota. Any CO2 from the project that is not used in EOR will be injected into a deep saline formation through SaskPower’s Carbon Storage and Research Centre.
The Global CCS Institute suggests that at least seven other large-scale postcombustion capture projects are in various stages of development worldwide, with most of the CO2 to be used for enhanced hydrocarbon recovery.
Along with Petra Nova and Boundary Dam, only one other large-scale CCS project at a power plant is actually under construction: Southern Co. subsidiary Mississippi Power is rushing to make headway and open the integrated gasification combined cycle power plant in Kemper County, Miss., in 2015. That project includes a precombustion carbon capture system that will use a physical solvent process (Selexol) to capture 3 Mtpa of CO2.
—Sonal Patel is a POWER associate editor (@POWERmagazine, @sonalcpatel)