RICHMOND, Texas— Every 17 seconds NRG Energy captures a ton of CO2 as part of the Petra Nova project at the company’s W.A. Parish Generating Station southwest of Houston, according to NRG Energy CEO Mauricio Gutierrez.

The project, in essence, uses various technologies to recycle one fossil fuel byproduct—CO2—to produce another hydrocarbon—oil.

The CO2 captured at what is now deemed by NRG and others as the world’s largest carbon-capture plant is transported via a 129-km (80-mile) pipeline to Hilcorp Energy. Hilcorp uses the CO2 for EOR at its West Ranch oil field in Jackson County, Texas.

The $1 billion project, which the U.S. Department of Energy greenlighted in 2010 for up to $190 million in grants, began operations in late 2016. On April 13, local, state and federal officials joined to congratulate NRG and project partners JX Nippon Oil & Gas Exploration of Japan and Houston’s Hilcorp.

U.S. Energy Secretary Rick Perry described the project as a display of innovation that shows how environmental concerns and fossil fuel needs can be solved together.

“The solutions to many of the challenges that we have in the world today are displayed behind me,” the former Texas governor told a crowd with the towering carbon capture facility as backdrop. Working with alliances across the globe, universities and the private sector, “there is no challenge that we cannot face and conquer. … This is a stunning display of what American and Japanese innovation working together can do.”

Perry called the project a “tremendous example of how investment in clean technology can also lead to increased development of conventional sources of energy. It shows we don’t have to pit the environment on one side of the lane and the economy on the other.”

Petra Nova, a 50-50 joint venture by NRG and JX Nippon, involved retrofitting the existing coal plant. Technology co-created by Mitsubishi Heavy Industries and Kansai Electric Power Co. was essential for the project.

Texas Gov. Greg Abbott commended those involved in the project and said the project helps address environmental concerns about natural gas and oil through technology.

“The greenhouse gases that scientists complain are a byproduct of energy production is now being corralled by innovation in Texas,” Abbott said. “The CO2 is being captured and being put to use doing what Texas knows best how to do, and that is producing even more energy from oil. Working with some of the best and brightest from across the entire globe, we can deliver innovative solutions to any challenge that exists out there.”

How It Works

Flue gas from the power plant is run through a flue gas quencher and cooled before a solvent, called KS-1, captures the CO2. The chemical has a socket that fits CO2, enabling the two to bind. The CO2 is then stripped from the solvent in a regenerator and compressed.

 

 

David Knox, communications director for NRG, explained during a media tour that about 40% of the flue gas from NRG’s Unit 8 is being moved into the carbon capture system. The amount is the equivalent of a 240-megawatt generating plant. Before the CO2 moves to the pipeline, destined for the oil field, most of the sulfur has been removed. At 1900 psi it’s enough pressure to make the entire 80-mile pipeline trip to the oil field, he said.

During the EOR process, the CO2 mixes with the oil, but “doesn’t change it chemically.” Altered physical properties make the oil more slippery, enabling the oil to move to the surface with more ease. The CO2 naturally bubbles out, then is recaptured, repressurized and injected back into the field. “Every time CO2 makes one of those orbits about 20% of the CO2 stays in the field.”

Production at the oil field was falling before the project.

Now, “The West Ranch oil field is getting a new lease on life,” Hilcorp Energy CEO Jeff Hildebrand said during the ceremony. “The project will enable production at the field to increase from about 300 barrels per day to a level not seen in decades.”

So far, the project has delivered more than 300,000 tons of CO2 to the oil field. Peak production is expected to reach about 15,000 bbl/d about a decade from now.

JX Nippon CEO Shunsaku Miyake added that CO2 injection is proceeding smoothly.

“This project enables us not only to decrease greenhouse gas from the coal-fired power plant, but also at the same time dramatically boost oil production.”

 

The Economics

Petra Nova is the first commercial facility of its kind in the United States, Gutierrez said.

“And we did it on time and on budget—no cost overruns, no delays,” he said.

The project is expected to capture more than 1.6 million tons of CO2 annually, which he said is the equivalent of taking 350,000 cars off the road.

Environmental benefits are apparent, but what about the economics? It partly depends on the oil price.

“We pay for this only through oil revenue,” Knox said, adding NRG has about a 50% stake in the oil field.

When ground was broken for the project about three years ago, oil was trading for about $100 a barrel. “This was going to make a fortune,” Knox said during the tour.

Then the energy industry found itself in one of its worst downturns with a supply glut that exceeded demand.

“After we broke ground oil dropped down to about $30 a barrel. I’ll be honest this was underwater. It was not going to make enough money to pay for itself.”

But rising oil prices have given the project a lifeline.

“At $50 oil it is making enough money to pay for itself—to pay for the operations, debt servicing,” he said. “So it is economically viable, but it is not making a lot of money for the return on investment. … If oil prices go up we’ll make more money on this.”

Hope also lies with the potential to expand to other oil fields, work with other companies that are developing new carbon capture technologies to bring costs down or sell the CO2 itself, getting out of the oil part of the business altogether.

“Our teams are already looking at what other oil fields we could go to,” Know told Hart Energy. “There are a lot of oil fields all around this area that could do it. ... After we have done this for 10 years there is no question of whether we can capture CO2 and deliver it on a routine basis.”

Velda Addison can be reached at vaddison@hartenergy.com.