Modelling carried out by the UK Energy Technologies Institute (ETI) predicts that offshore-wind technologies provide the best option should other technologies, including nuclear and carbon capture and storage, fail to deliver on their potential or be significantly delayed. Offshore wind could deliver energy at lower costs than all other forms of renewable energy, except onshore wind, and the ETI's analysis shows that its cost can be reduced significantly through the development of engineering solutions.
Succcessful technology innovation could account for up to 75% of potential cost reduction in the UK's offshore wind sector. New policy and regulatory interventions need to be developed, however, to encourage those who will have to take risks to help drive down costs further. Operators need to be confident of the future market to justify investing in these developments; policy makers must ensure the market is stable enough to encourage investment. Many lessons have already been learned. Now is not the time to shy away from investing further.
The UK government and industry are focused on bringing down the levelised cost of new offshore wind to £100/MWh (EUR 120/MWh) by 2020. That is an important milestone, but it is not the end of the journey. Commentators suggest that around £85/MWh will be required for offshore wind to be competitive with the cheapest low-carbon generation. Achieving this will be challenging, and it will take time — 2030 is a more realistic target date — but it is achievable.
As well as new technology and operating models, greater collaboration is needed between industry, governments and academia, and a significant boost in funding. This can lead to substantial private investment that will help unlock competitive advantage.
Bigger will be better
In the UK, we believe near-shore sites off south-west and north-east England and off Scotland's north-west and north-east coasts will be most suitable for investment. Accessing these sites will require the development of foundations for water depths of 30-100 metres.
The most cost-effective approach for producing electricity from offshore wind is likely to be very long bladed (100 metres) downwind direct-drive, horizontal-axis 10MW turbines, mounted on floating foundations to provide access to deep-water locations with high wind resources. Of the various types of floating foundations under development, we believe that tension-leg platforms are potentially very attractive.
The operating expenditure of offshore wind turbines accounts for one third of the total cost of the energy they produce. Operating and capital costs could be reduced by building fewer, larger units. This is why the ETI is investing in the demonstration of technologies such as floating platforms, long blades, condition monitoring systems and test rigs that could significantly cut the lifecyle costs of offshore wind.
Given the resources available to the UK, the rewards for successful development could be huge. Further spending on offshore infrastructure would generate economic activity. New supply chains can encourage job creation, export knowledge and technology across the globe, regenerate port infrastructure and create skills development opportunities required to service and nurture a burgeoning industry.
We must be bold in our cost reductions aspirations for offshore wind. Stakeholders need to see that the industry can deliver lower costs within a reasonable timescale. Technology innovation will play an important role in that goal.
Andrew Scott is programme manager, offshore wind, for the Energy Technologies Institute, a UK public-private partnership formed to address future energy challenges