Duke Energy is planning a “first-of-its-kind” project at its DeBary site in Volusia County, Florida, USA, that will demonstrate an “end-to-end system” for production, storage and combustion of 100% green hydrogen in an existing GE 7E gas turbine peaking unit, modified to run on a natural gas/hydrogen blend or up to 100% hydrogen.
The project, a collaboration between Duke Energy, Sargent and Lundy, and GE Vernova, will see the existing 74.5 MW DeBary solar plant provide power for two 1 MW electrolysers. The green hydrogen produced will be delivered to reinforced containers for safe storage. During times when energy demand is highest, the system will deliver the stored green hydrogen to the gas turbine. According to Duke, this will be the USA’s first combustion turbine to operate on such a high percentage of hydrogen.
“Hydrogen could play a major role in our clean energy future,” said Regis Repko, senior vice president of generation and transmission strategy for Duke Energy. In particular it provides power that is dispatchable, a needed element of reliability that enables more intermittent energy sources to be added to the grid, while still ensuring customer demand can be met even during extended periods of high demand.
Using solar energy to generate green hydrogen enables solar plants to be optimised, Duke notes. “Relying on intermittent energy sources without available dispatchable energy sources would put our future electric system at risk of having insufficient energy to serve customer demand.”
Construction of the DeBary demonstration project will begin shortly and Duke Energy anticipates the system will be installed and fully functioning in 2024.
GE Vernova says it began working with Duke Energy on a hydrogen plant readiness assessment in 2021. Following installation of the electrolyser equipment and hydrogen storage capacity on site, it will execute modifications to the existing gas turbine infrastructure at DeBary, including the fuel handling systems, valves and piping, making it compatible with higher blends of hydrogen, up to 100% by volume. GE Vernova will also install the fuel skid with hydrogen blending, finalise control modifications, and support overall integration.
When fully operational, the converted 83 MW 7E gas turbine will have the ability to operate on natural gas, liquid fuel, 100% hydrogen, or a blend of natural gas and hydrogen, “providing the site with complete fuel and operating flexibility while maintaining plant reliability.”
The 7E gas turbine to be modified for hydrogen is one of four such machines at the DeBary site, just north of Orlando, which also has six GE 7B gas turbines. Total installed gas turbine generating capacity is 692 MW.
Image (top): The DeBary site (courtesy of Duke Energy)
Image (right): End-to-end hydrogen system at DeBary (courtesy of Duke Energy)