TotalEnergies, Equinor among players pursuing decarbonization project for floating and fixed offshore installations

Norway-headquartered technology player Techouse is pooling resources with multiple energy companies, including TotalEnergies and Equinor, alongside SINTEF Energy Research, to develop and test a joint industry project (JIP), which aims to change the oil and gas industry’s mind about retrofitting offshore power generation with combined cycle to achieve cuts in fuel consumption and carbon emissions at floating and fixed offshore installations.

Given the project’s potential environmental benefits, the Norwegian Research Council has awarded NOK 12 million or nearly $1.1 million in funding for the JIP, which will develop and test a compact, lightweight once-through steam generator (OTSG) as a core component of offshore combined cycle power plants (CCPP).

This is said to be a heat and power solution where heat from the exhaust of the gas turbines is used to generate superheated steam, which is then used to produce additional power in a steam turbine. With a total budget of more than NOK 60 million or almost $5.5 million, the project is envisioned to enable a substantial reduction in fuel consumption and CO2 emissions from power and heat production at offshore installations.

As a result, the power output is expected to increase by 30-33%, or the required power is produced with 22-25% less fuel consumption, equivalent to cutting emissions between 50,000 and 150,000 tons annually per combined cycle power plant installation, compared to the conventional solution where only gas turbines are used for power and heating purposes on board an offshore installation.

The system is described as also providing heat to process heat. According to Techouse, the JIP, initiated by SINTEF Energy Research based upon efforts in a series of projects including EFFORT, COMPACTS, COMPACTS2, DigitalTwin, and the LowEmission Centre, which resulted in several scientific publications analyzing different aspects of critical for the design and operation of compact OTSG.

Svein Helge Pettersen, CEO of Techouse, explained: “Previous research and development has proved that implementing gas turbine combined cycle solutions on floating and fixed offshore installations results in 22-25 percent reduction in CO2 emissions compared to conventional gas turbine solutions. This joint industry project will make our OTSG even lighter and smaller so that it can be installed on even more offshore installations.”

The Norwegian player elaborates that the OTSG’s current challenge is the weight and size of the heat recovery equipment that creates steam from the gas turbine exhaust, thus, the JIP, will be developed and tested as a lightweight OTSG to prove the feasibility of building such a solution. Based on market reports estimate, greenfield projects alone need up to 75 new combined cycle power plants by 2030, provided applicability of the technology.

Tests are to be performed in regards to performance, vibrations, and fatigue, as the project’s target is to achieve a 40-50% cut in weight and a 10-15% reduction in footprint. SINTEF is expected to contribute to the project with analyses of compact steam bottoming cycles, inputs to the OTSG design, and analyses of the results from the OTSG demonstration project.

Pål Kloster, Sales and Business Development Director at Techouse, noted: “Most oil and gas offshore installations lacks available deck space and weight capacity. This is the challenge we are trying to solve. A smaller lightweight solution will increase the likelihood of adaptation of CCPP on offshore installations, also for fixed installations where weight is more critical than on floating installation.”

Techouse is collaborating with SINTEF Energy Research and several global multi-energy companies, encompassing TotalEnergies and Equinor, to complete the test project by the end of 2025, so that, the compact OTSG will be available as a commercial product in 2026. The Norwegian firm confirms that Equinor is in the process of retrofitting OTSG on its Statfjord C platform.

Equinor said in August 2023 that it had decided to change the power solution at its offshore platform in the North Sea to slash emissions by replacing two gas turbines with heat recovery to produce electric power, reducing annual CO2 emissions by 95,000 tonnes.

The new steam turbine, which is expected to enable cost-effective emission cuts, is scheduled for start-up in 2026. The project, named FLX Future Energy, encompasses the electrification of water injection and emission cuts related to other energy-intensive processes on Statfjord C.