Is produced water control the missing link among the top offshore emission-reduction strategies?

"We can always discuss the consequences of carbon emissions, but if you isolate the question, as you did in the poll, I think the most effective strategy is to impose regulatory requirements, such as CO₂ taxes," he said. "Whatever hurts the bottom line will always have maximum focus, at least that is what has happened in the areas where CO₂ taxes have been imposed."

Lager said produced water is the largest source of emissions in oil and gas operations due to its treatment and reinjection requirements. He added that the most effective strategy to reduce emissions is to address the root cause of produced water and that there has been a need for a technology that effectively retains the water in the reservoir. Density Activated Recovery (DAR) technology, recently qualified and set for offshore pilot testing by Equinor in early 2026, can control water influx downhole, significantly reducing emissions, costs and facility size, he said.

In this interview with Offshore, Lager explained that produced water has historically been overlooked as an emissions driver, but DAR technology, using density-based control rather than viscosity, offers a solution for autonomous downhole water management. 

Offshore: You mentioned that you heard an SPE spokesperson say produced water is the largest volume waste stream in hydrocarbon recovery and a major contributor to offshore emissions. Why has this issue been overlooked compared to other emission-reduction strategies, and what makes it so critical now?

Lager: Produced water management historically received limited attention because associated gas provided an almost free energy source for high-pressure water re-injection, which both disposed of contaminated water and supported declining reservoir pressure. The paradox is that as fields mature, water production increases resulting in more injection and processing, more energy consumption, and ultimately more emissions, exactly when oil production and revenues in a field are falling.

In recent years, emissions in general, as well as those specifically associated with water handling and reinjection in hydrocarbon recovery, have been recognized as unacceptable and resulted in costly emissions-reduction schemes like those mentioned in the poll. Emerging downhole water-control technologies have the potential to provide a low-cost alternative and essential lever for reducing emissions in both offshore and onshore activities.

Offshore: How is DAR different from traditional autonomous inflow control devices (AICDs), and how do these technologies enable effective water control under reservoir conditions?

Lager: DAR is fundamentally different from conventional AICDs because it uses fluid density, as opposed to viscosity to distinguish between oil and water. Density is a physical property unaffected by pressure, temperature or flow variations, which makes DAR far more stable and predictable throughout the entire life of a well. The way density control is applied in DAR provides unique capabilities and addresses challenges encountered in most wells, such as heterogeneities, permeability contrasts, depleted zones, faults, changing flow conditions and water breakthroughs throughout the life of a well.

When applied in a compartmentalized production interval, AICDs can react to changing fluid properties and restrict flow from compartments that are producing water. In light oil reservoirs, the viscosity contrast between oil and water is minimal, rendering technologies that are dependent on viscosity ineffective, limiting their application. Conversely, a density contrast between well fluids is assured, regardless of oil grade making DAR universally applicable in horizontal wells.     

Offshore: Equinor is set to pilot DAR technology in the Barents Sea. What factors led to Equinor's decision to adopt this technology, and what are the expectations for its performance in such a challenging offshore environment?

Lager: Equinor has been the global pioneer in adoption of inflow control technology, now viewing it as standard practice for horizontal wells. The next natural step for them is application of effective downhole water control, especially in challenging regions like the Barents Sea, an environmentally sensitive and remote location where subsea wells are tied back to an FPSO.

In Norway, high CO₂ taxes and the energy required for water reinjection make water production and reinjection a significant lifetime cost, making technologies that reduce water production and the related emissions highly relevant to the field’s business case.

Subsea wells in deep water offer the greatest potential for DAR because interventions to address water breakthrough are rarely performed due to cost and complexity. Autonomous downhole water control allows wells to produce predominantly oil, increasing revenues while reducing operational energy consumption and emissions.

Offshore: Can you share more details about the scope of the Equinor pilot, such as the number of wells involved, anticipated milestones and how success will be measured during the early deployment phase?

Lager: The pilot is a single-well application that includes approximately 1,700 meters of compartmentalized horizontal reservoir section completed with multiple DAR assemblies in each compartment. A successful installation will advance the technology from 'ready for piloting' to a maturity level appropriate for broad deployment in the company’s global portfolio of fields and projects.

We are currently defining early-life success criteria with Equinor, recognizing that water breakthrough varies widely between wells, occurring early in some cases and many years later in others. The lower completion will also be equipped with a chemical tracer to monitor system performance and provide early indicators of DAR’s autonomous response to controlling water.

Offshore: Beyond emissions reduction, you noted that DAR technology can reduce facility size and the number of wells required. How do these operational efficiencies translate into cost savings and sustainability benefits for offshore operators?

Lager: Without water-control measures, many offshore facilities become dominated by water handling, preventing new wells from being tied in and significantly restricting field potential. Expanding processing capacity offshore is often prohibitively expensive or impossible due to space and weight limits on platforms and FPSOs.

DAR autonomously suppresses water breakthrough, enabling longer wells to drain larger reservoir sections without cross-flow issues. This increases recoverable reserves, potentially reducing the number of producers and water injectors required to drain a field, and lowers both capex and opex. Reduced water production directly reduces emissions from handling and reinjection, delivering both economic and sustainability benefits.

Offshore: In the era of energy transition, how do you see technologies like DAR shaping the future of offshore oil and gas? Could this approach become a standard for balancing hydrocarbon recovery with environmental responsibility?

Lager: DAR enables higher oil recovery earlier in field life, before water cut and reservoir depletion push carbon intensity sharply upward. By accelerating production and shortening the late-life/tail-end phase, DAR will help lower overall Scope 1 and 2 emissions, reducing the need for costly secondary recovery measures, brownfield projects and related activities. By enabling recovery with smaller facilities, fewer wells and reduced operating emissions, DAR has strong potential to become a standard technology for balancing hydrocarbon recovery with long-term environmental responsibility.

Furthermore, maintaining high oil production can provide energy companies with the cash flow needed to support renewable energy projects and the energy transition in general.