In a global context where the climate crisis and water scarcity threaten the stability of entire regions, the Huaneng Dalian Second Reheat Seawater Desalination Project (Phase II) emerges as a strategic, innovative, and necessary response. More than 3 billion people live under severe water stress, and in China, per capita freshwater resources are less than one-fourth of the global average. Dalian, one of the coastal cities most affected by scarcity, faces a structural water deficit that limits both its industrial development and the quality of life of its population. In this scenario, Phase II of the project stands as an advanced technological solution and a model of water resilience that transforms a critical challenge into an opportunity for regeneration and self-sufficiency.
Located at No. 2 Haibei Street, Ganjingzi District, Dalian City, Liaoning Province, the project’s strategic objective is to ensure a sustainable water supply for the power plant and nearby communities, reducing dependence on urban water supply and the high costs of long-distance water transport. Its purpose lies in anticipating the impacts of climate change on water availability and strengthening industrial water security through a robust, efficient, and environmentally responsible system.
With a projected capacity of 100,000 tons per day and a two-stage reverse osmosis system, the project converts reheated seawater into a safe and useful resource, equivalent to the annual consumption of more than 180,000 households. Through an integrated approach combining cutting-edge technology, energy management, and water benefit traceability under the Volumetric Water Benefit Accounting (VWBA 2.0) framework, this plant does not simply produce water, it redefines the relationship between energy, water, and sustainability.
The project involves key stakeholders at every stage: the national energy developer and operator, specialized suppliers of high-efficiency membranes, local engineering firms, environmental authorities, and external verification entities that ensure compliance with the principles of additionality, traceability, and intentionality. In line with the global Water Positive vision, Liaoning Dalian consolidates itself as a tangible example of resilient and regenerative infrastructure, demonstrating that every desalinated liter can become a liter returned to the natural system, measured, verified, and with real impact on the basin.
Located on the Dalian coast, the Huaneng Dalian Phase II project represents an unprecedented technical and strategic opportunity to address the structural water scarcity in northern China. Through the use of two-stage reverse osmosis, energy recovery, and PLC automation, the system converts reheated seawater into a reliable freshwater source, producing 100,000 tons per day, equivalent to the annual consumption of over 180,000 households. This capacity makes it one of the largest industrial desalination complexes in Asia, capable of supporting the region’s energy and urban growth with minimal environmental footprint.
The intervention leverages existing Phase I infrastructure and optimizes it with high-efficiency equipment and state-of-the-art materials, reducing energy and operating costs by 20%. Immediate benefits include reduced emissions associated with water transport, recovery of thermal energy from the turbine condenser, and total brine reuse, ensuring zero-effluent discharge. This approach not only improves operational sustainability but also enhances the developer’s environmental reputation, positioning it as a pioneer in low-carbon desalination.
The project is made possible through a consortium comprising the national energy developer, local engineering firms, international membrane manufacturers, and external verification organizations that ensure transparency and traceability of results under Water Positive and VWBA 2.0 principles. This multi-actor alliance is key to guaranteeing the technical credibility and replicability of the model.
Its success underscores the urgency of acting now: industrial water demand in northern China is growing by 6% annually, while natural resources are rapidly depleting. Replicating this model in other coastal areas will not only diversify water sources but also help companies achieve ESG goals, strengthen climate resilience, and position participants as leaders in the new water economy.
The Huaneng Dalian Phase II project falls under the gray infrastructure and industrial demand category according to VWBA 2.0, focusing on generating new water from non-conventional sources through advanced desalination. The selected technology, two-stage reverse osmosis with integrated energy recovery, resulted from a comparative analysis of alternatives such as thermal evaporation, nanofiltration, and multi-effect distillation, chosen for its superior balance between efficiency, energy cost, and final water quality. With a capacity of 100,000 m³/day, the plant represents a hybrid solution, gray and digital, combining robust physical infrastructure with intelligent real-time monitoring.
Implementation is structured into three stages: technical design, pilot operation, and full-scale execution. The first stage defined optimal flow, pressure, and temperature parameters to maximize energy performance and minimize membrane fouling. The second stage validated isobaric energy recovery efficiency and optimized multimedia pretreatment to reduce chemical consumption. Finally, the operational phase consolidates a system with hydraulic redundancies, SCADA alarms, and a predictive maintenance protocol.
The project’s technical and strategic justification lies in resolving the structural freshwater scarcity affecting Dalian and its energy industry. In this context, advanced desalination is the only viable alternative to hydrological variability and saltwater intrusion that degrade coastal aquifers. Selection criteria prioritized energy efficiency (<3.2 kWh/m³), model replicability, environmental regulatory compliance, and alignment with Water Positive principles, additionality, traceability, and intentionality. Each cubic meter produced is digitally recorded and linked to volumetric benefits verified under VWBA 2.0.
Quantifiable benefits include an annual recovery of 130 million m³ of water, a 20% reduction in energy intensity, and a 15% improvement in industrial water quality. Environmentally, the project avoids groundwater extraction, reduces over 41,000 tons of CO₂ per year, and prevents untreated brine discharge, protecting marine ecosystems. Socially, it generates skilled local employment and ensures stable supply for nearby communities, while economically reducing operating costs by 12% and strengthening the operator’s ESG reputation.
Identified risks include potential membrane failures, variability in seawater salinity, and environmental risks related to brine management. Mitigation measures include redundant pumping systems, operational contingency plans, and a shared governance mechanism involving the company, environmental authorities, and coastal communities. Safety protocols include continuous osmotic pressure monitoring, alarms for contamination or saline intrusion, and periodic emergency simulations. Long-term resilience is ensured through corrosion-resistant materials, energy storage, and adaptability to climate change scenarios projected by the China Meteorological Administration.
Finally, the project’s scalability extends to other coastal regions, such as Shandong, Tianjin, and Hebei, and industrial sectors with high water demand. The model’s cost-benefit ratio (0.65 USD/m³) and fast payback period (<7 years) make it highly competitive. Expansion relies on public-private partnerships, international technological cooperation, and regulatory frameworks promoting non-conventional water reuse. The result is an integrated system combining innovation, sustainability, and governance to ensure long-term water security.
The project is implemented under a phased and adaptive approach, designed to ensure traceability, operational control, and long-term resilience. Implementation is organized into clearly defined phases, each with specific technical objectives, timelines, and control mechanisms.
Phase 1 – Diagnosis and Design: This initial stage includes hydrological, climatic, and energy assessments using GIS and CFD models, defining baseline and key performance indicators (KPIs). Parameters such as seawater salinity, baseline energy consumption, and pre-project losses are analyzed to establish the “without project” scenario. The technical design optimizes resource use, incorporates osmotic pressure simulations, and models reverse osmosis membrane behavior under varying temperature and salinity. This phase is completed within 9 months.
Phase 2 – Construction and Installation: Over approximately 14 months, modular assembly of reverse osmosis units, auxiliary photovoltaic systems, heat exchangers, and high-pressure pumps with isobaric energy recovery is conducted. SCADA and IoT systems with electromagnetic flowmeters and multiparameter probes (pH, conductivity, turbidity, temperature) are implemented. Each module undergoes hydraulic and electrical testing before full integration, ensuring physical traceability of water from marine intake to storage.
Phase 3 – Commissioning and Technical Validation: Lasting 6 months, this phase includes instrument calibration, quality parameter validation, and energy efficiency verification. Performance indicators are benchmarked against the baseline using accredited laboratories and online monitoring, ensuring compliance with ISO 14046 and VWBA 2.0 guidelines. External validation protocols with independent verifiers certify volumetric and environmental benefits.
Phase 4 – Continuous Operation and Monitoring: During operation, the system reaches a nominal capacity of 100,000 m³/day with efficiency above 95%. Real-time control via cloud-connected IoT sensors detects deviations in flow, pressure, or salinity. Automatic alarms trigger contingency protocols, including pressure adjustments, membrane cleaning, or activation of redundant systems. Annual external audits and performance reports align with VWBA/WQBA frameworks, comparing “with project” versus “without project” scenarios.
Phase 5 – Governance and Maintenance: Operation is led by a technical consortium headed by the developer, with participation from environmental authorities and external verifiers. Responsibilities are clearly defined: the operator handles preventive and corrective maintenance; the basin committee validates water balances; and external verifiers certify results under transparency and traceability principles. The preventive maintenance plan includes quarterly inspections, controlled chemical cleaning, and scheduled membrane replacement.
Phase 6 – Continuous Improvement and Technological Updating: Active throughout the project lifecycle, this phase incorporates operational data feedback, technological upgrades, and annual VWBA indicator reviews. Results are published in public reports and integrated into CEO Water Mandate databases, strengthening global water governance.
Overall, the project guarantees a smart water management model with total physical, digital, and operational traceability, ensuring every liter of produced, reused, or regenerated water is measured, validated, and transparently reported.
The Huaneng Dalian Second Reheat Seawater Desalination Project (Phase II) constitutes a comprehensive technological intervention aimed at transforming the region’s water supply through a two-stage reverse osmosis system with energy recovery. Technically, the process captures reheated seawater from the power plant’s cooling circuit, subjects it to physicochemical pretreatment, multimedia filtration, activated carbon, and antiscalant dosing, and then drives it through high-pressure reverse osmosis modules producing industrial-grade desalinated water. Infrastructure includes high-efficiency pumps, heat exchangers, isobaric energy recovery valves, and a real-time SCADA monitoring and control system. The operating flow reaches 100,000 m³/day, with a conversion efficiency above 45% and strict compliance with ISO 14046, WHO, national marine discharge, and energy management standards.
The solution’s relevance lies in its ability to reverse Dalian’s structural water deficit and aquifer overexploitation, which have caused saltwater intrusion and deterioration of inland water quality. Before the project, the city relied on external water sources with high logistics costs and low resilience to climate variability. With this plant’s implementation, a stable, predictable, and sustainable supply is ensured, reducing pressure on natural sources and improving both industrial and urban water security. The model transforms a critical state of vulnerability into an opportunity for regeneration, ensuring operational continuity for the energy sector and environmental quality for the community.
Expected results are concrete and measurable: 130 million m³ per year of new water added to the system, a 20% reduction in energy consumption per cubic meter, a 15% improvement in industrial water quality, and a 41,000-ton annual CO₂ reduction. Additionally, the zero-discharge and marine ecological compensation system minimizes environmental impact and supports coastal biodiversity. These benefits extend to public health by ensuring supply stability and water quality, and to the local economy through more than 300 direct jobs and a specialized maintenance chain.
From a strategic perspective, the project aligns with the Water Positive roadmap and frameworks such as VWBA 2.0, Science Based Targets for Water (SBTi), and Net Positive Water Impact (NPWI), reinforcing the company’s leadership in water sustainability. Tangible ESG benefits include strengthened social license to operate, recognition as a pioneer in low-carbon water innovation, and compliance with international reporting standards like ESRS E3. Commercially, it represents an opportunity to attract green investment and consolidate reputation in highly regulated markets demanding sustainable water management.
The model’s replicability is high. It can be applied in other coastal regions of China, such as Tianjin,
