Autonomous, robotic and AI enabled biofouling monitoring, cleaning and management systerm for offshore wind turbine monopile foundations - RoBFMS

"Offshore wind is an attractive option for operators, primarily due to higher yields and less resistance from onshore homeowners and stakeholders. Within the UK the exploitable resource is especially attractive, at 6200TWhpa, ~18 times present UK electricity consumption and hence could provide all of the UK's electricity requirement with minimal emission and visual impacts. More than 5GW of installed capacity has been achieved in UK waters, enabled by government subsidies. The major barrier to further exploitation is that the levelized cost of electricity (LCOE) from offshore wind is £140/MWhr. 2-3 times higher than other key renewable sources: onshore wind, solar and nuclear (a large non-renewable but low emission source). The high LCOE is caused by the severe environment which results in high operational, reliability and maintenance (O&M) costs. Seabed turbine foundations (largely monopile structures) O&M accounts for at least than 25% of all life cycle O&M costs, mostly caused by marine biofouling amounts to 10% of the LCOE. Even with the deployment of state of the art fouling prevention technology, the fouling thickness deposited on foundations grows continuously, eventually causing stress induced corrosion and crack defects. Fouling remediation treatment consists of deploying cleaning tools such as brushes and power jets by divers (which is dangerous) or ROVs with annual costs ~ £30k/MW.

The project will develop a fouling management system consisting of a mobile survey robot leading a cleaning robot team that will eliminate be need for divers and ROVs. The team will be placed on the turbine structure at sea level and will journey down below sea level to the work place. The lead robot will travel autonomously over the entire subsea monopile surface, imaging the fouling and measuring its thickness in real time at every location where it occurs. Simultaneously the leader will instruct one or more cleaning robots to every fouled location and remove the fouling with an innovative guided power ultrasound technique. On returning to the sea surface the team would simply be transported to the next turbine scheduled for treatment and the cycle repeated. Overall O&M costs will be reduced by at least 50% compared with present diver/ROV techniques. This would mean a £7/MW (5%) reduction in LCOE. This is a significant contribution to the overall LCOE reduction required to make offshore wind competitive with other energy sources and thus reap the full environmental advantages of offshore wind."