OceanAlpha illustrates how the China General Nuclear Power Group utilized an OceanAlpha M80 Unmanned Surface Vehicle (USV) alongside the Echoscope 4G from Coda Octopus to identify wind turbine pile foundations and underwater cables at the Ruhai Wind Farm.
Operational Overview:
The OceanAlpha M80 USV is deployed from a mother ship to the designated survey area. Equipped with advanced 3D sonar technology, the USV conducts surveys to locate pile foundations and cable routes as per the predetermined mission plan.The operator receives real-time detection data transmitted back to the mother ship via a secure private network.
Project Background:
The Ruhai Wind Farm, managed by China General Nuclear Power Group (CGN), is situated in the Yellow Sea, east of Rudong in Jiangsu Province. Officially operational as september 8, 2016, the wind farm faces challenges such as erosion of pile foundations and the potential exposure of submarine cables, which can jeopardize the safety of offshore wind energy production. Regular inspections for erosion of these structures are essential.
Traditional survey methods using workboats are frequently enough expensive and hindered by the size and draft of the vessels. Manual operations between wind turbines pose collision risks and reduce efficiency. Thus, there is a pressing need for innovative survey solutions tailored for wind farm assessments.
Innovative Solution:
To address these challenges, CGN implemented the OceanAlpha M80 USV in conjunction with the Echoscope 4G sonar system for effective detection of wind turbine foundations and underwater cables.
The benefits of utilizing USVs for this purpose include:
- Compact design allows for enhanced maneuverability and efficiency
- smart collision avoidance systems minimize accident risks
- High precision in line tracking ensures reliable data collection
- eliminates the need for personnel to wade into potentially hazardous waters
Survey Execution:
The OceanAlpha M80 USV can operate autonomously from the wharf or in conjunction with the mother ship.It transmits real-time data through various communication channels, including public networks, private networks, satellite links, or connections between booster stations and land. This setup allows operators to effectively monitor pile foundations and cable erosion from either the shore or the mother ship.
Operational diagram
Survey Process Flowchart
The USV can navigate autonomously to the designated locations of the pile foundations and underwater cables, maintaining a positional accuracy of less than 1 meter. Additionally, mission routes can be stored for future reference and ancient data analysis.
USV Surveying Around Pile Foundations
Outcomes:
Final Thoughts:
This initiative marks a pioneering application of USVs in China for surveying pile foundations and assessing underwater cable erosion in wind farms. The USV’s agility,adaptability,and enhanced safety features effectively address the limitations of traditional survey methods in challenging marine environments.
When compared to conventional workboat maintenance, USVs offer superior positioning accuracy and control, with a smaller turning radius that reduces collision risks. Their precise tracking capabilities substantially boost survey efficiency.
Moreover, employing USVs for collaborative surveys can substantially enhance operational efficiency while lowering carbon emissions. As a notable example, a survey mission covering 50 square kilometers could see a reduction in overall survey time by 75%, along with an 83% decrease in fuel consumption and carbon output when utilizing one mother ship and four USVs working together.
Looking ahead, USVs are poised to leverage their intelligent, efficient, precise, and safe characteristics to undertake a variety of tasks with different payloads. They are set to replace traditional manpower in high-intensity, high-risk, and repetitive offshore operations, ushering the offshore wind energy sector into an era of automation and intelligence.
