Energy efficiency in dredging operations
Index
1. Introduction
2. What does energy efficiency mean in dredging?
3. Available quantitative data
4. Strategies for improving energy efficiency
5. Italian case studies
6. Towards more efficient and sustainable dredging
7. FAQ
8. Main sources
Introduction
Energy efficiency in dredging is now one of the sector's strategic priorities, both to reduce operating costs and to align with the decarbonization targets set at European level. In a context where dredging operations are becoming increasingly frequent—for port maintenance, reservoir management, or mining projects—energy consumption is becoming a key indicator of technical and economic sustainability.
According to a paper by the Central Dredging Association (CEDA), the energy consumed per unit of dredged material is expressed in kWh per cubic meter (kWh/m³) and varies depending on the type of sediment, depth, transport distance, and characteristics of the pumping system. However, the systematic measurement of these values is still not widespread, particularly in Italy.
What does energy efficiency in dredging mean?
Energy efficiency in dredging refers to the amount of energy required to remove and move one cubic meter of material. The main sources of consumption are:
● Cutting and suction system (cutterhead + pump + riser pipe), responsible for up to 90% of total energy consumption according to Yuan et al., 2025 (MDPI).
● Auxiliary systems such as jet rings, agitators, hydraulic excavators, and handling systems.
● Transport and relaunch of material, which increase proportionally to the pumping distance.
Specific cutting energy is a useful metric for comparing different dredging systems. It represents the amount of energy required to remove a unit volume of material and allows for the optimization of operating parameters (rotation speed, flow rate, pressure).
Available quantitative data
International sources indicate average values for sand or compact sediment dredging operations of between 25 and 35 kWh per ton of dredged material (BMAPA, 2023). In European projects such as HELENUS, the goal is a 20% reduction in consumption compared to current benchmarks.
In Italy, there are still no public databases reporting standardized energy consumption values (kWh/m³). However, companies in the sector point out that factors such as seabed morphology and transport distance significantly influence consumption.
Strategies for improving energy efficiency
The main strategies adopted in the sector concern:
● Optimization of the operating cycle: adjusting the feed rate, depth, and rotation of the cutterhead according to the type of material.
● Pump-cutter matching: balancing power and flow rate to reduce pressure losses in the pipes.
● Automation and predictive control: using sensors and algorithms to monitor parameters in real time and automatically adjust energy delivery (Bakker et al., 2023).
● Logistics and fleet management approach: plan dredging and transport cycles to minimize downtime and consumption, as shown by De Boer & van Halem, 2022.
● Life cycle analysis (LCA): evaluating not only direct energy consumption but also the overall environmental impact throughout the entire operating cycle (CEDA, 2023).
Italian case studies
1. Dredging of a dam using a low environmental impact system (Udine)
In a reservoir in Friuli Venezia Giulia, Dragflow removed approximately 30,000 m³ of clayey silt using three HY85/160 hydraulic pumps with side cutters and jet rings. The system achieved a production rate of 1,400 m³/day, maintaining low turbidity levels thanks to an anti-turbidity bell also designed by Dragflow.
2. Dredging of the Port of Piombino
In the Piombino Port revitalization project, Dragflow supplied an HY85 hydraulic pump, two EXHY35 excavators, a Jet Ring, and a Power Pack for sand dredging with discharge over 500 meters away.
3. Beach nourishment in Sardinia
Another Italian case study concerns a beach nourishment project at Forte Village in Sardinia, where Dragflow electric pumps were used for the controlled transfer of sand. The use of electric systems, compared to traditional hydraulic ones, has led to a significant reduction in emissions and fuel consumption.
Towards more efficient and sustainable dredging
The future of dredging in Italy will involve the digitization of operations and the adoption of integrated energy monitoring systems. The aim will be to define unambiguous indicators such as kWh/m³ of material removed, parameters that allow comparison between projects and technologies.
At the same time, the integration of electronically controlled pumps, hybrid systems, and electric dredgers represents a promising direction for reducing consumption. European initiatives for the decarbonization of the maritime sector, promoted by EuDA and CEDA, provide a fundamental framework for accelerating this transition.
FAQ
What is the average energy consumption in dredging operations?
It depends on the type of material and the technology used. International studies indicate a range of 25–35 kWh per ton of dredged material.
What technologies improve energy efficiency?
Electric pumps, hybrid systems, automation with predictive sensors, and the use of optimized cutters are among the most effective solutions.
Is there any official Italian data?
Not currently. Italian estimates are derived from projects such as those carried out by Dragflow, but there is no public database that collects standardized consumption values (kWh/m³).
What are the environmental benefits of efficient dredging?
Reduced emissions, lower turbidity, fuel savings, and compliance with European decarbonization targets.