Climate change is one of the main challenges of the current society and the energy transition from Climate change is one of the main challenges of the current society and the energy transition from polluting fossil fuels to clean energy sources is the key to stopping this trend. However, society is a great energy consumer and oceans are the principal energy container of the world. Effective harnessing of Offshore Renewable Energy (ORE) sources is thus, the main goal.
Research on ORE systems is being held for the last decades. However, planning, installation and maintenance of ORE farms is complex and expensive, increasingly as they move further from thecoast, where greater resource can be found, and devices interrupt less the human activities in the sea.
The global objective to tackle this challenge is to facilitate the generation of Offshore Renewable Energy sources by improving the technology that leads to a cost reduction in theplanning, installation and maintenance phases.
The Joint Research Laboratory on Offshore Renewable Energy (JRL-ORE), a scientific community composed of researchers of TECNALIA, UPV/EHU and BCAM with the aim of boosting the researchin the field of Offshore Renewable Energy, will respond to this challenge by developing technologies that an Autonomous Underwater Vehicle needs for its use in Offshore Renewable Energy Inspection.
Keeping in mind our main objective of lowering the cost of Offshore Renewable Energy (ORE) production, it is essential:
- To lower the cost of the planning of offshore parks:
- Both when selecting the area in which to locate the park
- In the search for the precise location of each one of the devices.
- To lower the cost of park maintenance:
- By automating the inspection and maintenance of submerged structures and thereby automating the inspection and maintenance of submerged structures and their surroundings.
An Autonomous Underwater Vehicle (AUV) could help in reducing the costs of such activities.Different technological and scientific challenges arise for having an efficient AUV:
- Systems for the characterization of the seabed and its variation over time: coupling portable penetrometers, sensors, sample collection. Evaluation of sediment movement around submergedpenetrometers, sensors, sample collection. Evaluation of sediment movement around submergedstructures, characterize rock bottom fracturing for the selection of anchor zones in rock drilling.
- Conceptual design of an AUV: suitable for underwater displacements, autonomous, withstand conceptual design of an AUV: suitable for underwater displacements, autonomous, withstandhigh pressures
- Autonomy of AUVs (various challenges): underwater wireless recharging, offshore power sourcesand energy storage, underwater data transmission; and uncertainties: selection of best frequencies for underwater wireless, pressure effect on the equipment, calculation of losses in water, corrosive and conductive mean, etc.
- Underwater vision systems: 3D digitization of the seabed, sensors and data processing to detectcracks and other damage. Detection of the degree of anchor penetration
- Cleaning techniques: (elimination of biofouling) generation of pressurized water, coupling of arms/ tools
- Positioning techniques in open underwater spaces (GPS)
One of the main scientific-technological challenges to achieve the costs reduction both in planning and maintenance of ORE farms is to characterize the seabed and its variation over time in anefficient and economical way.
To meet this main challenge, a series of secondary challenges must be addressed, such as:
- Develop a method to measure the inclination of rock layers on the seabed. This allows to know the structure of the rocks in the area, application in offshore renewables to anchor in rock, application in oil & gas and underwater construction, to prepare geological maps of the offshore
- Develop a method to measure the rock bottom fracturing network. This allows to evaluate the quality and resistance of the rocky massif. Application in offshore renewables to anchor in rock application in underwater construction
- Characterize the evolution of sedimentary bottoms over timeIt allows to evaluate the sedimentation and erosion processes in a given area and to know theeffect of the sedimentary dynamics in the submerged structures- Application in the detection of underwater landslides, application in the selection of sites for offshore farms- Application in maintenance of submerged structures: wind turbines, oil & gas platforms,submarine cables, outfalls, moorings, anchors, pipes, etc.
- Measure the mechanical and geotechnical properties of the seabedIt allows predicting what the behavior of the seabed will be before any type of human action in theenvironment (moorings, anchors, soundings, structures that lay on the bottom, ...) Application in any field that requires installing a structure or device on seabed that are coveredwith sediments (The applications of this challenge are enormous: Construction companies, mining companies, engineering companies, energy companies, electricity companies, oil companies, ports, fish farms ...)
As shown, in addition to the potential benefits for the offshore renewable energy sector, an efficient AUV will also benefit the oil & gas sector.
- The challenge is envisaged as a collaborative project that allows to increase the key knowledge to develop the AUV.
- It will stablish a challenge-based training programme, were individual small challenges will beproposed.
- Last year university students will be involved within research groups towards solving each ofthe small challenges.
- Partial projects will have the possibility of being the base of a doctoral thesis.
The first step of the research is developing a comprehensive review of the state of the art of the key aspects of the AUV, both, finding the frontier of knowledge of the key technologies, and looking att he key stakeholders of the whole chain. Involving not only research groups from the University ofthe Basque Country (UPV-EHU), Tecnalia and BCAM but also interested private companies willensure a comprehensive search for the solution to the described challenge and provide both theparticipants and the project itself with an interdisciplinary and multiorganisational added value.