It’s well accepted that natural gas power plants are an important part of the energy transition in support of more renewables being added to the grid. They can reliably generate hundreds of megawatts of baseload electricity with a relatively low carbon intensity and quickly adjust their output to match changes in demand and in supply from weather-dependent renewable sources like wind and solar farms.
But despite all their benefits, natural gas is a fossil fuel that produces carbon emissions — albeit much less than coal. That’s why GE Gas Power, which manufactures some of the world’s most advanced gas turbines, is partnering with governments, technology providers and customers to unlock ways to decarbonize gas-fired power stations, which today generate nearly 25% of the planet’s power, a number that is expected to increase over the next decade to support the growth of variable renewables and declines in technologies including coal-fired power in some countries.
One way to do it is to integrate carbon capture, utilization and storage (CCUS) in existing natural gas-fired power plants. The approach aims to capture carbon dioxide (CO2) that would otherwise be emitted and either trap it safely underground or reuse the gas in the making of other products as varied as oil and synthetic materials. Large-scale adoption of CCUS, however, has been elusive, mainly because many projects struggle to be economically viable. GE is now working in collaboration with other entities and stakeholders to change this.
One example is the work with the U.S. Department of Energy, which is taking a new look at integrating CCUS with an existing natural gas-fired power plant. The agency will be funding with $5.77 million a GE-led study that will explore ways of lowering the cost of CCUS while reducing CO2 emissions from natural gas power plants by up to 95%. GE engineers and their peers from Southern Company, Linde Engineering, BASF and Kiewit expect to spend 18 months studying the engineering, cost and integration of the proposed CCUS project at the James M. Barry power plant in Alabama.
The James M. Barry plant, operated by Alabama Power, a subsidiary of Southern Company, uses two of GE Gas Power’s 7F.04 gas turbines. The Department of Energy’s goal is to help achieve the Biden-Harris administration’s goal of net-zero carbon emissions by 2050 and a 100% clean electricity sector by 2035. “CCUS is critical to curtailing the [greenhouse gas] emissions from fossil fuel-based power plants in the near to mid-term to achieve the net-zero goals and decarbonization pledges from governments and customers across the globe,” says Parag Kulkarni, general manager of carbon capture solutions at GE Gas Power.
Industry Road Map
The study could end up as the energy industry’s roadmap for carbon capture from existing and new gas-fired power plants. Turbines from GE’s 7F family make up North America’s largest gas turbine fleet. Worldwide, approximately 1500 F-Class units are in operation, generating up to approximately 280 gigawatt-hours per day. And engineers can likely use the same recipe to retrofit GE’s other turbine families. “Our approach would be applicable for the smallest aero-derivatives all the way through to the B and E class and the newest HA plants,” says John Sholes, a principal investigator for the DOE FEED study at GE.
GE will be leading a team on the Barry project. Linde has experience with post combustion amine-based carbon capture processes, while BASF will provide OASE® blue technology that was developed specifically for large-scale post-combustion capture (PCC) technology. Those two engineering heavyweights have partnered before on carbon capture projects. Meanwhile, Kiewit will provide engineering procurement construction capabilities. But it is GE that will be in charge of joining up all the dots, and working toward integrating a single, whole CCUS solution at the power plant.
This is why generators and policymakers are watching the Barry project closely. Previous studies focused on adding carbon capture technology to the natural gas power plant have used a “bolt-on” strategy for carbon capture equipment. But here, the equipment will be integrated across components including the gas turbine, heat recovery steam generator, steam turbine and plant controls. “The Barry project will represent a fundamental change in how the plant will operate,” Sholes says. “CCUS projects need to look at the plant in a holistic way in order to be successful.”
To achieve integration, the GE-led team will work on the front-end engineering design (FEED) study, which consists of a detailed blueprint and operating business guide. This plays to GE’s strengths in natural gas, combined-cycle plant engineering, operability and plant integration. GE, which is anticipating strong global demand for CCUS integration in coming years, is also working with Technip Energies in a separate FEED study for carbon capture at a proposed gas-fired power plant in Teesside, an industrial hub in the U.K.
A power plant with fully integrated CCUS could capture a higher proportion of greenhouse gases with lower impacts on the plant capex, opex, footprint and operability. Previous DOE-funded field studies captured around 90% of a gas-fired power plant’s carbon emissions, but GE’s engineers are aiming to attain 95%, Sholes says. At the Barry plant, that would translate into slashing CO2 emissions by more than 600,000 metric tons per year, according to Sholes. “That’s huge. It is the equivalent of eliminating the CO2 emissions of over 130,000 cars each year,” he says.
This approach could also benefit consumers and the generator’s business case for adding CCUS to the power plant. Depending on marketplace factors such as the presence of a carbon tax or the need to purchase carbon credits, and the prevailing prices associated with those schemes, lower emissions reduce the need for the operator to purchase carbon credits or pay more CO2 taxes, which in turn allows a plant to compete more effectively on wholesale prices with other gas-fired power plants. This then could bump a plant into a good position for the times when a renewables-heavy grid would need a power boost. That, in turn, could help raise the facility’s annual operating hours, producing lower power prices in dollars per megawatt-hour, Sholes says.
The project at a full-scale plant could hasten the adoption of CCUS, says John Catillaz, director of decarbonization marketing at GE Gas Power. In the meantime, he hopes policymakers and operators will study the various barriers to widespread adoption — a major one being the need for financial mechanisms, which can take many forms, to accelerate the adoption of the technology.
However that plays out, Scott Strazik, chief executive of GE Power, is optimistic that his engineers can usher in an era of large-scale carbon capture. Says Strazik: “We are committed to leading a more sustainable power industry that will provide the world with the more affordable, reliable and less carbon-intense electricity it needs today, while maintaining laser focus on researching, developing and demonstrating the technologies that will be required for the future.”