“Previous research and development have proved that implementing gas turbine combined cycle solutions on floating and fixed offshore installations results in a 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,” says Svein Helge Pettersen, CEO of Techouse.
Due to the technology’s innovative nature and significant potential environmental benefits, the joint industry project (JIP) has been awarded NOK 12 million in funding from the Norwegian Research Council. The project’s total budget is more than NOK 60 million.
Heat and Power Solution
The JIP aims to develop and test the new, compact, once-through steam generator (OTSG) as a core component of offshore combined cycle power plants (CCPP). The combined cycle is a heat and power solution where heat from the exhaust of the gas turbines is used to generate superheated steam. The steam is then used to produce additional power in a steam turbine.
The result is that power output increases by 30–33 percent, or the required power is produced with 22–25 percent less fuel consumption, compared to the conventional solution where only gas turbines are used for power and heating purposes on board an offshore installation. The system also provides heat to process heat.
The challenge with today’s OTSG solutions is the weight and size of the heat recovery equipment that generates steam from the gas turbine exhaust. In this JIP, a lightweight OTSG will be developed and tested to prove the feasibility of building a robust, lightweight OTSG. Important tests will be performed with respect to performance, vibrations, and fatigue. The JIP target is to achieve a 40–50 percent reduction in weight and a 10–15 percent reduction in footprint.
“Most oil and gas offshore installations lack 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,” says Pål Kloster, sales and business development director at Techouse.
Up to 150 kt Lower Annual CO2-Emissions
The compact OTSG is expected to change the oil and gas industry’s current reluctance against retrofitting offshore power generation with combined cycle.
Reducing fuel consumption and CO2 emissions by 25 percent is the equivalent of cutting emissions between 50,000 and 150,000 tons annually per combined cycle power plant installation.
Market reports estimate greenfield projects alone need of up to 75 new combined cycle power plants until 2030 provided applicability of the technology.
Ready in 2026
Techouse is collaborating with SINTEF Energy Research and several global multi-energy companies, including TotalEnergies and Equinor, to complete the test project by the end of 2025. The objective is that the compact OTSG will be available as a commercial product in 2026.
The project has been initiated by SINTEF Energy Research based upon efforts in a series of projects, including EFFORT, COMPACTS, COMPACTS2, DigitalTwin, and the LowEmission Centre. This work has resulted in several scientific publications analyzing different aspects critical for the design and operation of compact OTSG. SINTEF Energy Research is an independent research institute for applied research dedicated to creating innovative energy solutions. SINTEF will contribute with analyses of compact steam bottoming cycles, inputs to the OTSG design, and analyses of the results from the OTSG demonstration project.
Techouse has experienced exponential interest-growth in its technologies during the past five years. Equinor is for example in process of retrofitting OTSG on its Statfjord C platform.