Innovative maintenance for wind farms

Industrial use of drones in the offshore sector

Wind farms are set to make up a significant share of the mix of renewable energies. Innovative and cost-optimized maintenance and servicing concepts are required for the sustainable operation of wind turbines. Drones will play an important part in these concepts. Fraunhofer IFAM is developing and validating components, systems, and procedures to realize reliable operations with unmanned aircraft systems (UAS) in the offshore area.

More tailwind for offshore wind energy

In order to reduce CO2 emissions, Germany is attempting to strongly expand the share of renewable energies across all sectors — including offshore. In the amendment to  the WindSeeG, additional expansion targets of 20 GW by 2030 and 40 GW by 2040 were defined for offshore wind energy. This requires increasingly larger outputs and rotor diameters for offshore wind turbines (WTGs). At the same time, wind farm operators are coming under increasing pressure in regard to cost of energy production, with operating costs providing an optimization approach in this regard. To this end, current research at Fraunhofer IFAM is focusing on innovative maintenance and repair concepts.

Drones save costs and CO2

The use of highly automated drones or UAS in the inspection and maintenance of wind turbines can have an enormous impact on cost reduction (e. g., by up to 90 percent through autonomous long-term inspections). Furthermore, there is a lesser risk to humans in the field when climbing offshore turbines during inspections. The same is true for cost and risk reduction of offshore hydrogen productioninfrastructures. Similarly, the use of transport UAS can be leveraged to provide small- to medium-sized spare parts at short notice and reduce operating costs and CO2 emissions by replacing helicopter flights.

Drones for offshore use

Nevertheless, today there is a lack of suitable automated UAS for offshore use. The aim is therefore to significantly accelerate the development and validation of UAS components, systems, and processes for the realization of missions near- and offshore. This means driving forward the industrialization, Digitalization, and automation of UAS and also includes inspection of infrastructure, emergency logistics, transport and environmental monitoring, for example.

In addition to purely technical developments research is also being conducted into solutions in the regulatory field. The goal here is a coexistence of both manned and unmanned aviation in the lower airspace. This includes new solutions for short-term, automated operational authorizations, warning and detection systems as well as solutions for the joint efficient use and coordination of airspace.

Offshore maintenance in wind and weather

In the near future, unmanned aircraft systems (UAS) are expected to significantly improve and accelerate the inspection and maintenance of offshore wind turbines (WTGs).

The “AIDA” project aims to raise the offshore use of UAS to a level suitable for industry by significantly increasing the degree of automatisation of UAS operations (in the offshore domain/maintenance). Taking into account different aspects (from ship platform to technical requirements of the UAS), mobile sensory inspection procedures will also be developed and validated. UAS are thus expected to contribute to a more efficient, costeffective and safer operation of WTGs.

Measurements under real environmental conditions are a major challenge - especially when the flight systems have to touch the surface of offshore structures with pinpoint accuracy in the air. In the “AIDA” project, Fraunhofer IFAM is developing and validating metrological systems for equipping UAS to reliably perform these types of contact measurements offshore.