Nature of Business and Basis of Presentation	12 Months Ended
Dec. 31, 2025
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Nature of Business and Basis of Presentation	NOTE 1 — Nature of Business and Basis of Presentation Nature of Business NET Power Inc. (“Net Power” or the “Company”) is an energy technology company focused on delivering low-carbon gas power solutions. Historically, the Company’s sole business has been the development of a novel oxy-combustion power generation system (referred to as the “Oxy-Combustion Cycle”) designed to produce reliable and affordable electricity from natural gas while capturing virtually all atmospheric emissions. During the third quarter of 2025, the Company completed a market analysis of the Oxy-Combustion Cycle, identifying slower than anticipated acceptance and deployment of the technology from previous expectations coupled with costs not currently economic in the marketplace. In response to unprecedented demand growth for low-cost, firm power generation solutions with viable pathways to decarbonize, the Company broadened the scope of our business to include the generation of power using natural gas turbines paired with PCC technology that we intend to license from Entropy. In order to preserve capital for this new business opportunity, the Company paused all development work and related expenditures for its first utility-scale power plant utilizing the Oxy-Combustion Cycle (“SN1”). In December 2025, we suspended testing efforts at our La Porte Demonstration Facility. Risks and Uncertainties The Company is subject to a number of risks, including, but not limited to, reliance on relationships with strategic investors and partners for successful deployments of power plants, the requirement for additional capital to fund development and construction of our projects, the commercial viability of the proprietary technology and related projects we intend to deploy, competition from other power generation technologies, permitting and construction delays, supply chain constraints, protection of proprietary technology, and changes in the governmental and regulatory environment. Basis of Presentation The accompanying consolidated financial statements are prepared in accordance with accounting principles generally accepted in the United States of America (“US GAAP”). The functional and reporting currency of the Company and its subsidiaries is the U.S. dollar. Reclassification of Prior Period Amounts Certain prior period financial information has been reclassified to conform to current period presentation.

Nature of Business and Basis of Presentation

12 Months Ended

Dec. 31, 2025

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Nature of Business and Basis of Presentation

NOTE 1 — Nature of Business and Basis of Presentation

Nature of Business

NET Power Inc. (“Net Power” or the “Company”) is an energy technology company focused on delivering low-carbon gas power solutions. Historically, the Company’s sole business has been the development of a novel oxy-combustion power generation system (referred to as the “Oxy-Combustion Cycle”) designed to produce reliable and affordable electricity from natural gas while capturing virtually all atmospheric emissions.

During the third quarter of 2025, the Company completed a market analysis of the Oxy-Combustion Cycle, identifying slower than anticipated acceptance and deployment of the technology from previous expectations coupled with costs not currently economic in the marketplace. In response to unprecedented demand growth for low-cost, firm power generation solutions with viable pathways to decarbonize, the Company broadened the scope of our business to include the generation of power using natural gas turbines paired with PCC technology that we intend to license from Entropy. In order to preserve capital for this new business opportunity, the Company paused all development work and related expenditures for its first utility-scale power plant utilizing the Oxy-Combustion Cycle (“SN1”). In December 2025, we suspended testing efforts at our La Porte Demonstration Facility.

Risks and Uncertainties

The Company is subject to a number of risks, including, but not limited to, reliance on relationships with strategic investors and partners for successful deployments of power plants, the requirement for additional capital to fund development and construction of our projects, the commercial viability of the proprietary technology and related projects we intend to deploy, competition from other power generation technologies, permitting and construction delays, supply chain constraints, protection of proprietary technology, and changes in the governmental and regulatory environment.

Basis of Presentation

The accompanying consolidated financial statements are prepared in accordance with accounting principles generally accepted in the United States of America (“US GAAP”). The functional and reporting currency of the Company and its subsidiaries is the U.S. dollar.

Reclassification of Prior Period Amounts

Certain prior period financial information has been reclassified to conform to current period presentation.