The wind sector is growing rapidly, increasing in scale and complexity, with larger windfarms being developed in deeper waters and further from the shore.
According to the 2015 International Energy Agency’s (IEA) Renewable Energy report, renewable energy will represent the largest source of electricity growth over the next five years, driven by falling cost and aggressive expansion especially in emerging economies.
These developments provide exciting opportunities in the industry, however rapid growth and increasing complexity threaten to increase operation and maintenance (O&M) costs and safety risks. As a result, new techniques need to be continually assessed in order to help reduce O&M costs and improve safety.
Cutting Edge Solutions
With the growing number of wind turbines now in service, inspection and maintenance is imperative in order to identify any potential damage or indications of early problems. Undetected damage can be highly detrimental to operations, reducing energy generation capacity and can ultimately lead to catastrophic asset damage.
This has presented an increasing requirement for safe and cost efficient inspection, which also addresses the need to ensure downtime is minimised. This requirement has attributed to the significant rise in the use of Remotely Operated Aerial Vehicles (ROAV), otherwise known as Unmanned Aerial Vehicles (UAV) or drones, to complete turbine inspections at wind farms.
Since 2008, Cyberhawk Innovations has been spearheading the industrial use of ROAV technology, growing to become the world leader in aerial inspection and survey using this technique.
Headquartered in Livingston, Scotland, with bases in the Middle East and SE Asia, Cyberhawk uses ROAVs to conduct close up inspections of live and difficult to reach structures, such as offshore meteorological masts. For the last three years, Cyberhawk has been inspecting wind turbines both onshore and offshore, and has worked on the majority of the UK’s offshore wind farms.
The company’s highly skilled teams of ROAV pilots and experienced inspection engineers have completed more than 10,000 commercial flights, 2,000 structural inspections and have achieved over 25 world firsts using ROAV technology.
2015 marked Cyberhawk’s busiest year in the renewables industry, with work in the sector increasing tenfold. The company operated throughout the UK and Europe, inspecting over 500 wind turbine blades and multiple metrological masts and working with clients including RWE, SSE, Siemens, Vestas, Forewind, EDPR, Repsol and Dong Energy. 2016 is already shaping up to be the company’s busiest year yet, as a growing number of wind farm operators recognise the huge benefits on offer.
Wind turbine inspections tend to differ between the onshore and offshore industry.
In the longer established onshore wind sector, inspection tends to take place using rope access or elevated work platforms. This can present potential working at height risks, not to mention significant costs and lengthy periods of shutdown. For offshore wind, many operators are still working to identify the most efficient and safest methods of inspection however issues similar to those experienced in onshore wind are likely to be the case.
All of the above can lead to a potential reduction in inspection scopes and thus preventative maintenance, and many operators are now learning of the detrimental effects this can lead to further down the line. Even slight leading edge damage can affect the aerodynamic efficiency, reducing annual electricity production and increasing loads through the drive train.
Cyberhawk is proving that the benefits of using ROAVs for data capture in the renewables sector are substantial. Along with considerable cost benefits, the use of ROAVs significantly improve safety by mitigating the need to work at height. Inspection speed is three to four times faster than traditional methods and a visual record covering the entire blade or even the entire turbine is achieved.
The vast improvements in efficiency offered by ROAVs are illustrated by a recent project, which Cyberhawk undertook for a major OEM. One Cyberhawk field team completed more than 30 wind turbine inspections in less than 10 days, with an average downtime of only two hours per turbine. This meant that the client’s turbine production time was significantly maximised, creating huge efficiencies for the operator.
The Winds of Change…
Historically ROAVs in the renewables industry have experienced challenges in systematically and consistently capturing a photographic record of each surface of the turbine blade and delivering reports that provide accurate defect measurement and positioning.
Together with Cyberhawk’s innovative inspection technique, and extensive industry knowledge, the company’s wind focused asset management software presents a game-changing solution to deal with these challenges, for both onshore and offshore wind farm operators. Developed in-house, iHawk Wind is a browser based asset management system which is designed to allow clients to quickly and easily understand the condition of their assets from the huge volume of high-definition data captured by ROAVs. The software allows Cyberhawk to accurately size defects and positioning, to +/- 5mm, and locate them on the blade from root and leading edge.
Using a map-based interface and displaying asset condition using a traffic light colour coding system, users can delve further into findings to view high definition images and engineering commentary of the full asset being inspected and specific defects identified. The software ensures that a full record of each asset is available and facilitates year-on-year comparison. iHawk also allows the download of a traditional defect-per-page pdf report.
The development of iHawk means that wind farm operators now have access to an innovative solution which dramatically improves the wind turbine blade inspection arena. With the cost, time and efficiency benefits on offer, not to mention the drastic safety improvements, there is no excuse for neglecting inspection. Cyberhawk’s ROAV inspection solution is already becoming established as best practice in the industry and is set on a path for exponential growth as more and more operators understand the benefits of the technology.
In 2015, Cyberhawk was approached by one of the UK’s largest energy suppliers. The brief was to inspect more than 100 wind turbines throughout the company’s Scottish and Irish wind farms, with minimal loss of operational downtime and in timescales that would allow them to meet yearly inspection targets.
The inspections included close visual inspection of the leading edge, training edge, pressure and suction sides of each blade. Specific locations and sizing of each defect were essential in order to determine the damage and prioritise the maintenance required.
Cyberhawk’s asset management software, iHawk, allowed the client to quickly understand the condition of its wind farms and access high definition images of the entire blade surface of every turbine, as well as engineering commentary. These images also allowed the client to see the severity of the defect for themselves, and ultimately prioritise repairs and allocate budgets.
Traditionally, the inspections would have been carried out using rope access technicians, however this technique increases man hours on site and in turn, increases the risk and likelihood of injury. The use of ROAVs mitigated these risks, and also meant reduced downtime for the client. One of Cyberhawk’s key USPs is the ability to inspect three to five turbines per day, compared with rope access which will typically only inspect one.
The client also reported that Cyberhawk’s technology made a significant improvement to project safety. On at least two occasions turbines were not re-started on site after an inspection was carried out and revealed a safety critical defect.
Cyberhawk’s certified technicians and trained inspection engineers allowed the inspections to take place with minimal client supervision. The client reported a high level of confidence in the autonomous role given to the company’s inspection teams and based on this, as well as other positive feedback, Cyberhawk has been given the opportunity to perform a larger work scope in 2016.