Puffer

WHY

Offshore wind turbine blades face various types of damage due to the challenging environment in which they operate. This includes issues like material fatigue, surface damage, cracks, lightning strikes, and leading edge erosion. If these problems aren’t properly addressed, they can affect the blades’ performance and lead to turbine failures and a significant loss of energy production.

To reduce blade erosion, offshore wind farm operators regularly inspect, clean, and repair the blades. Currently, this is mainly done using a rope access method, where specialised technicians make precise repairs along the entire blade. While rope access is relatively safe, it requires extensive training and can only be used in certain weather conditions. This makes it a complex and costly solution, with limited available personnel and long downtimes for the turbines.

To tackle these issues, Ampelmann is developing a blade-repair capsule called “Puffer”. This blade-access platform allows technicians to work safely while being lifted from the nacelle and attached to the blade. The platform can reach the blade's entire length using controllable winches, making maintenance safer and more efficient. This technology could help address the shortage of rope access workers, lower health and safety risks for technicians, reduce dust and falling particles into the environment, and extend the operational time. This will help lower maintenance costs.

The Puffer can be used in both onshore and offshore wind farms, but it focuses mainly on offshore applications. The current prototype has been successfully tested onshore and can be used on 3 MW wind turbines, covering the full length of the blades.

WHAT

The Puffer is a new technical solution that hasn’t been tested in offshore wind farms yet. In this project, we aim to gather insights on how to best configure this technology to improve blade repair. We will focus on reducing maintenance costs, lowering environmental emissions, and increasing its technology readiness level. Testing offshore is not part of this project; that will be addressed in a later phase.

In this project, we will:

1. Validate the economic and environmental benefits of the Puffer compared to traditional rope access. The platform will have the greatest impact on large blade repairs. Fast start-up times and lightweight will ease the logistics for blade repair campaigns.
2. Identify the critical design drivers of the Puffer that strongly influence the maintenance costs. This will provide insights into the critical design drivers to maximise the added value of the Puffer.
3. Evaluate the use cases of the Puffer in different blade maintenance strategies. This will provide insight into the comparison between the Puffer and other solutions available in the market.
4. Test and validate the improved design of the Puffer. In this way, we will validate the previously identified improvements of the Puffer. The current status is that it is an operatable device, but the platform needs improvement in terms of start-up time, manoeuvrability, and operability for technicians to perform repairs. Our goal is to completely redesign of the Puffer structure and winch so that the Puffer becomes suitable for blade repair onshore.

EXPECTED RESULTS

The project aims to raise the technology readiness level from its current level of 5 to level 7. We want to gain detailed insights into how future blade repair strategies can reduce maintenance costs. Additionally, we will evaluate the economic and environmental impacts of the Puffer, focusing on identifying key design factors that significantly influence maintenance costs.

The project will lead to:

1. a tested, validated, completed and optimised design of the maintenance platform PUFFER,
2. a lower levelised cost of energy of offshore wind energy by reducing the costs of blade maintenance activities,
3. an improvement in the annual energy production of offshore wind farms,
4. safer working conditions for technicians and less impact on the environment.