The impact of climate change on offshore wind operations
A recent report prepared by JBA Consulting (JBA) under a Copernicus Climate Change Service (C3S) contract - administered by the European Centre for Medium-range Weather Forecasting - provides thought-provoking insight into the potential effect of climate change on European offshore wind Operations and Maintenance (O&M). The report raises questions around the attainability of national offshore wind targets and draws into sharp focus, the need for long term strategic decision making.
Here, we summarise the key findings of the report and the implications that they may have for policy and decision makers within the offshore wind sector.
Climate change is expected to affect both the supply and demand of energy. As the energy sector transitions towards a low carbon economy dominated by renewable energy sources, the relevance of climate variability and change also increases. It is vital that energy providers and policy makers have the climate information they need to make informed choices on the future energy mix.
The C3S contract delivered by JBA supports the energy sector by providing climate-related information, such as wind, wave and sea level at a regional and national level in Europe. It demonstrates the impact of present day and future climatic conditions on the offshore wind industry.
Using metocean data from the C3S repository, the Climate Data Store (CDS), the contract evaluated the impact of climate change on key metocean variables. Data from a single global/regional climate model was used for several locations and climate epochs (namely: historical 1977-2003, near-future 2041-2070 and far-future 2071-2100). Analysis of these data revealed that there was typically a small reduction in wind speeds and wave heights predicted.
ForeCoast® Marine, JBA’s metocean risk management software, was also used to allow a more sophisticated assessment of the impact of climate change on O&M to be performed. Simulating the operation of the wind farm, the software included the generation of revenue from the turbines, turbine failures, and the repair of these failures using vessels. Given that each of these factors is strongly influenced by metocean conditions, any changes in climate conditions have the potential to impact the performance of a wind farm.
Modelling was based on an offshore wind farm configuration representative of the next generation of wind farms, comprised of 100 ten megawatt (MW) turbines. Wind farms were modelled at a number of locations in Europe with a range of Climate Impact Indicators (CIIs) being produced from the simulations including:
Available energy - which represents the theoretical maximum energy that could be generated if there was no turbine downtime
Generated energy -which represents available energy minus any lost generation due to turbine downtime, and
The variations in the CIIs were summarised by comparing historical conditions to a future climate scenario (RCP 8.5). On average, across all simulated locations, the analysis revealed the following changes to Europe’s potential offshore wind portfolio by 2085:
3% decrease in available energy
3% decrease in generated energy
0.2% increase in turbine availability.
Implications for the offshore wind industry
So, what do these percentage changes in CIIs mean for Europe’s offshore wind industry? To quantify the impact, the percentage changes were converted to absolute values, using a number of conversion factors. Based on the assumption that Europe’s offshore wind installed capacity will be 190 GW by 2085, a 3% reduction in generation was calculated to equate to the following headline figures (all relative to if the weather stayed as it is today):
A decrease of 16 TWh/year
€1,000 million/year in missed revenue
A reduction of eight million tonnes CO2/year in replaced fossil fuel use and
Four million less homes powered.
This study indicates that, in Europe, climate change may decrease the amount of energy produced by an offshore wind farm. For offshore wind farm operators, this may affect the viability of a wind farm or require innovations in terms of turbine design or maintenance strategies.
With regards to the energy policy in Europe, reductions in Available and Generated wind power may influence the scale of development required to achieve targets as additional turbines or potentially even whole wind farms may be needed. In this regard, strategic decision making can be strongly supported using the results and data within the CDS. By coupling the CDS data with modelling software, like ForeCoast® Marine, we explore potential mitigation strategies and areas where innovation should be focused.
It is important to note that the climate change impact information presented in this report was based on data from a single available climate projection ensemble member. As climate modelling is uncertain, the results should therefore be treated with appropriate caution.
However, the study does, for the first time, provide evidence that climate change has the potential to significantly influence the performance of offshore wind farms and to create additional energy challenges if mitigation strategies are not put in place. Therefore, this study has highlighted the need to further explore the impact of climate change on the offshore wind sector and for this research to influence the direction that the sector takes in terms of innovation.