Allowing offshore wind farms to operate for up to 35 years would increase cost efficiency and electricity yields, according to a new German study.
The German Association of Energy and Water Industries (BDEW) today published a study prepared by the Fraunhofer Institute for Wind Energy Systems IWES.
The study looked at the continued operation and subsequent use scenarios of offshore wind farms and grid connection systems.
It outlined the benefits of extending the 25-year operational lifecycle of offshore wind farms to 35 years.
The operating licences of the first large offshore wind farms in Germany expire from around 2040. This means the turbines will have to be dismantled even if their continued operation would be technically, economically and legally possible.
BDEW said this must be questioned in terms of sustainability, including ecological impacts on the marine environment.
BDEW called for a coordinated approach to offshore wind. In the existing offshore wind clusters of the North Sea, several wind farms with different durations are often connected to a common grid connection system.
In addition, existing farms are to be merged into larger areas with 2GW grid connection capacity in the future, which requires coordination in terms of operating times, demolition and new construction.
Against this background, the Fraunhofer IWES study examined various continued operation and post-use scenarios, using the example of an offshore wind farm cluster in the German North Sea.
Among other things, operating and investment costs, failure rates, dismantling and idle times as well as ship and supply chain capacities were included.
BDEW said the results of the study show that coordinated continued operation of the turbines for up to 35 years with subsequent dismantling and new construction can increase electricity yields in the cluster and reduce economic costs over the entire period.
This is compared to a scenario with direct dismantling and new construction after 25 years of operation.
At the same time, BDEW said the scenarios with coordinated continued operation place comparatively moderate demands on supply chains and lead to lower burdens on the ecosystem.
“The study illustrates that a coordinated continued operation of offshore wind farms and grid connection systems can have significant advantages for cost efficiency and environmental balance in offshore wind expansion,” said Kerstin Andreae, chairwoman of the BDEW executive board.
“It is crucial that operators are given planning security as early as possible in order to adapt operation and maintenance strategies accordingly and to specifically address the susceptibility of systems to failure, which increases with age.”