Water-flooding is a widely used technique for pressure maintenance or improving sweep efficiency. Incremental recovery of water-flooding ranges from 15 to 25%. Nonetheless, water-flooding is an energy-intensive activity. Water injection systems typically consume 30 to 50% of field total power consumption. For many oilfields on the Norwegian Continental Shelf (NCS), the percentage is much higher, where more than half of the energy on a platform goes to water injection pumps. Thus, water-flooding significantly contributes to the amount of GHG emission. In this presentation, we present a methodology to design a water-flooding strategy in which it reduces CO₂ emission while sustaining field production and economics.