Continuous monitoring of the structural condition of the tower and supporting structure of floating and static offshore wind turbines.
TowerPower is a EU collaborative project consisting of 12 partners (4 SME-AGs, 5 SMEs, 3 RTDs) working to develop suitable and reliable techniques for monitoring the offshore wind turbine tower.
Offshore wind energy turbines have the potential to deliver a higher power output than the onshore wind turbines. Nonetheless, they are less competitive due to higher operating and maintenance costs. According to a 2011 wind energy operations maintenance report, offshore wind turbines O&M costs are 2 to 6 times higher than on-shore wind turbines. 66% of these costs are caused by unscheduled, corrective maintenance.
The tower structure failures represent only 5% of total failures but they are responsible for more than 22% of the associated downtime. A typical substructure for an offshore wind turbine generator consists of a foundation structure (piles/buckets), a Monopile/Jacket, a Transition Piece and a Tower.
Relying on a network of sensors, amplifying electronics and advanced signal processing algorithms, the TowerPower solution will enable self-learning of the normal behavior "signature" of the structure and to detect any deviation from the initial record. Meanwhile, the system will contribute to a better understanding of physic-chemical phenomena leading to flaws triggering.
Simulations carried out show how the AE wave travels in the tower with reflections and scattering help to understand how to place the AE sensors efficiently. The system will continuously monitor the structure, detecting the evolution of the degradation of the structure and anticipating when a component has to be replaced. Thus, the system will enable to avoid failures altogether and implement predictive maintenance. Predictive maintenance limits considerably Operating & Maintenance costs as it reduces the cost of maintenance by doing maintenance at the appropriate time; limits the downtime by scheduling carefully the maintenance operations and most importantly avoids failure of the structure altogether.
Economically, the TowerPower project will enable wind operators to push the wear-out time further extending the effective life of wind turbines and decreasing considerably the downtime during their operational and wear-out phases. The cost of an offshore wind turbine is approximately 1,3M€/MW. Under normal operating conditions, maintenance costs are 500K€/year. 30-40% of the maintenance costs are inspection related. Failure costs related to structure failures do in some cases exceed 10% of the total overall maintenance costs without taking into account the loss of production due to downtime. Successful implementation of the TowerPower system will reduce the inspection time by up to 50%, which equates to 50-75K€/year. The reduction of the downtime associated with scheduled maintenance will further gain 40-60K€/year.
For more details, please visit - http://www.towerpower.eu