In the last five years, the UK’s offshore wind industry has built enough new capacity to power three million homes[1]. With around 1,465 offshore wind turbines[2], keeping these “healthy” is no easy task but vital to protecting high levels of productivity and efficiency as well as avoiding high maintenance costs and mitigating the risk of disruption.

As renewables continue to make up a growing proportion of the UK and global energy mix, minimising and preventing disruptions are vital to the sector’s growth and ability to capitalise on the changing energy agenda.

Wind turbines at Galloper wind farmIntermittency and redundancy pose a significant threat to the reliability and effectiveness of offshore wind farms. Operating in extreme environments with limited or challenging accessibility means that processes throughout the lifecycle of a project face significant risk.

Failure of on-site power, temperature control or ventilation equipment can prove fatal to an operation. In some cases, if a turbine was to lose power it could take weeks to dry out. Apply this scenario to an entire wind farm and a project’s ability to generate capacity is jeopardised. Furthermore, if a turbine is not operational for several weeks, its warranty is lost forever.

This is where contingency planning and a proactive approach is vital. While power generated from the turbine can often be fed back from the substation, this is not always possible or an automatic process. On-site, modular power or temperature control systems mitigate the risk of downtime and ensure minimum disruptions to operations.

Back-up plans and early implementation should be applied across all stages of the lifecycle from construction, operation and at some point, decommissioning.

Following a site survey, a disaster recovery plan should be developed, which covers the required equipment and load requirements, site accessibility and a potential call-out sequence. All of this helps to reduce timescales to recovery in a critical or emergency situation.

When the wind turbines on the Greater Gabbard field, off the Suffolk coast in England, were erected offshore, there was no mains supply available to power the ancillary equipment contained within the structure. Normally this power is supplied from the National Grid via subsea cables, but these were still to be laid and commissioned.

Aggreko worked with operators to fill this gap and ensure the anti-corrosion system on turbines was functional. A combination of high and low voltage power was required to allow vital heaters and dehumidifiers to run.

We also provided a temporary power supply and climate control equipment during the build of the substation and while it was offshore prior to mains connection, preventing deterioration of the HV equipment and switchgear. Providing a domestic power supply for the offshore workforce was also crucial to maintaining high productivity and safety.

As more offshore wind farms are developed – approximately 14 in Europe alone over the next three to four years, including the Galloper project – the role of modular power during the construction phase will grow. As will the need for contingency planning and mitigating the risk of disruption.

Every minute costs. With a new growth phase in offshore wind farms on the horizon and the next round of CFDs due early next year, it is vital for a development’s short and long term prospects that deadlines are met. Power loss and resulting implications should not be the reason for lost opportunities.


 

[1] https://renewableuk.com/en/publications/reports.cfm/UK-content-of-operating-offshore-wind-farms

[2] UK Wind Energy Database (UKWED) https://renewableuk.com/en/renewable-energy/wind-energy/uk-wind-energy-database/index.cfm