Petra Nova Parish Post-Combustion CCS Sequestration Project

Executive Overview

Petra Nova is the world's largest post-combustion carbon capture and sequestration facility on a coal-fired power plant, retrofitted onto Unit 8 of NRG Energy's W.A. Parish Generating Station in Thompson, Texas, southwest of Houston. The system commenced commercial operation on December 29, 2016, and was jointly developed by NRG Energy and JX Nippon Oil & Gas Exploration (a subsidiary of ENEOS Holdings). Total project cost was approximately $1 billion; the DOE contributed $195 million in federal cost-share through the Clean Coal Power Initiative Round 3 programme. The capture facility treats a 240 MW slipstream of flue gas, designed to capture approximately 1.4 million metric tonnes of CO₂ per year at a 90% design efficiency. Captured CO₂ is compressed and transported via an 81-mile pipeline to Hilcorp's West Ranch oil field for EOR and sequestration more than a mile below surface. The facility was taken offline in May 2020 due to low oil prices during COVID-19, and restarted under ENEOS Xplora sole ownership in September 2023. Cumulative CO₂ captured has exceeded 5 million metric tonnes.

How It Works & Differentiation

The capture system uses Mitsubishi Heavy Industries' KM CDR Process with KS-1 proprietary amine solvent: flue gas from Unit 8 is directed into an absorber column where the solvent binds CO₂, then the solvent is heated in a stripper to release a concentrated CO₂ stream. A dedicated 78 MW GE 7EA cogeneration gas turbine provides the steam and electricity for the capture process, consuming approximately 34–35 MW of electrical power and 500,000 lbs/hr of steam. Average capture efficiency during the three-year demonstration period was 92.4% of the 240 MW slipstream. The EOR application at West Ranch produced over 4.2 million barrels of incremental oil, providing the revenue stream that partially offset operating costs. CO₂ purity exceeded 99%.

Commercialization & Traction

Petra Nova's operational history is the most detailed post-combustion CCS dataset from a coal power application in the world, and its DOE final scientific report provides granular performance data on amine solvent degradation, compressor reliability, and availability factors that directly inform subsequent CCS engineering. Actual plant availability was below the 85% target due to outages — 141 full days in 2017, 101 in 2018, and 49 in 2019 — a documented constraint on the business case. NRG Energy sold its 50% stake to JX Nippon in 2022 for approximately $3.6 million, less than 0.5% of NRG's original construction investment. Under ENEOS Xplora's sole ownership, the facility is positioned as the demonstrator for the ENEOS Group's CCS/CCUS growth strategy, against a 2040 carbon neutrality target for the group.

Scalability & Strategic Context

Petra Nova remains the only large-scale post-combustion CCS facility on a coal power plant operating in the United States. Its business model — CO₂ EOR revenue offset against capture operating costs — was structurally dependent on oil prices above approximately $50–60 per barrel, explaining the 2020 shutdown. The project's core technical lesson is that post-combustion capture at this scale is achievable at 90%-plus efficiency from the slipstream, but achieving commercial viability requires either sustained high oil prices for EOR or a direct carbon price mechanism. The $195 million DOE investment and the full project dataset represent one of the most significant public investments in power sector CCS demonstration infrastructure in U.S. history.