Stuart Bradley shares his views on Floating Wind Technology

4th November 2015

It may seem an obvious statement given that the UK is an island nation where the wind often blows but there are abundant renewable energy resources that can and are being exploited off our coast.

Conversely there are also significant locations that could deliver cost-effective, safe and secure offshore wind which are not currently being developed.

Offshore wind technology is a relatively mature, well understood industry with significant deployment in water depths less than 40 metres.

The UK already has the world’s highest offshore wind capacity with over 4GW installed, over 1100 turbines in place, a further 1.4GW in construction, and the world’s largest in-service offshore wind farm is in the outer Thames Estuary.

With continued technology and supply chain development this provides a clear and credible trajectory to delivering commercial offshore wind farms.

However, much of this planned and installed capacity is concentrated in shallower waters off the east coast of the UK, which means there are many locations benefitting from stronger, more consistent wind speeds that are not currently being developed.

One reason for this is that deeper water sites, which are relatively close to the shore, are currently inaccessible due to limitations in the depth to which traditional fixed foundations can be deployed.

To further reduce the costs of generating electricity from offshore wind farms there needs to be access to good quality wind resource which is close to the shore and power users so that the costs of maintenance and transmission are as low as possible.

Using floating offshore wind platforms in these areas could open up new commercially exploitable sites.

In water depths of less than 30m traditional fixed foundations will be the prime solution, but, in water depths over 50m floating foundations provide the lowest cost solution so a mix of these technologies is likely to offer the lowest cost pathway to deliver mass offshore wind deployment in UK waters.

As well as having strong wind speeds, sites suitable for floating wind platforms need to have water depths greater than 40 metres and be less than 100 km from shore so they don’t need expensive transmission systems.

Using this criteria could open up areas of the Irish Sea, Eastern and North Eastern Scotland, North Western Scotland and North Eastern England.

Analysis in our reoport 'Floating Wind Technology' suggests that floating wind technology has the potential to deliver a levelised cost of energy of less than £85/MWh by the mid-2020s, allowing it to compete with the lowest cost forms of low carbon generation.

So, developing and demonstrating this technology should be seen as a key strategic issue for the UK.

Today, floating foundations are still some way from large scale deployment and the offshore wind industry is currently focussed on delivering Round 3 sites in shallower waters.

To develop this crucial technology there needs to be policies in place to encourage its development and test sites ready to demonstrate its capability before large scale deployment takes place.

The timescales for developing wind farms are long and new technology needs to be proven, so if floating wind is to be deployed at scale from the mid 2020s, demonstration projects need to be in place within the next five years if the UK is to capitalise on the benefits they offer.