Abstract
Abstract The increasing focus on reducing carbon emissions from offshore operations highlights the urgent need for efficient integration of renewable energy sources with traditional offshore processes. A significant challenge is the intermittent nature of wind power, which affects the reliability of the energy supply and the injection stability of offshore platforms. As a potential solution to this challenge, our group has earlier proposed a methodology for subsurface energy storage, where injection capacity above reservoir injection limits is diverted into a storage reservoir. This pressurized water in the storage reservoir is led back into the producing section during low-energy periods. The objective of this work is to test the methodology in a real field application. The methodology uses wind power energy to run the water injection pumps. The injection is prioritized to the oil bearing and producing reservoir, any surplus energy exceeding the producing reservoir injection limit will be directed to a hydrodynamically isolated storage reservoir. During periods of insufficient wind power to maintain target injection rates, fluid from the pressurized storage reservoir is allowed to flow into the producing reservoir through intra-well crossflow to maintain injection continuity. This study applies the methodology to a modified version of the Norne Field, a mature field in the Norwegian Sea. A major modification of the model involved changing one of the layers to be impermeable to create the isolated storage reservoir and facilitate crossflow in the injection wells. Assessing the impact of wind power intermittency and energy storage performance on oil production is performed based on this modified model. The study evaluates the results using three scenarios for seven year injection-production period: Case 1: the injection was kept constant with no limitations on power supply, Case 2: variable injection rates depended on available wind power, Case 3: variable injection rates depended on wind power, with excess wind power used to inject into the storage layer and the stored energy partly regained during low wind periods. Results indicate that Case 1 achieved the highest cumulative oil production, as expected. Case 2, depending only on wind power, resulted in a 3.4% reduction in cumulative oil production. However, Case 3, which combines energy storage and wind power, showed only 1.6% reduction in oil production compared to Case 1. The findings of this study provide new insights into optimizing the use of renewable energy in offshore energy systems by effectively managing the intermittency.