In recent years, the uses for drones have dramatically expanded, as online retailers, the construction industry, wildlife rangers and the media, to name just a few, explore the ways drones can make their day-to-day operations easier, safer and more efficient. Utilities have also been quick to explore the potential applications for drones, and here we take a look at the benefits utilities around the country are seeing through the use of drones.
For more than a century, drones, or unmanned aerial vehicles (UAVs), were viewed purely as a military device. But in recent years, a dramatic shift has taken place, with a wide range of non-military applications identified for drones.
From aerial photography to 3D mapping to agricultural applications, drones are quite literally spreading their wings into new uncharted territory.
John Perkins is the UAV Chief Pilot for utility industry service provider Select Solutions, and has closely followed the early adoption of UAV technology in the utility sector in recent years.
“The utilities world has been quick to take notice of the capabilities of UAVs, with many utilities across the country identifying applications for UAV technology in their own operations.
“Perhaps the most obvious use for UAV is in the realm of asset inspection; but this is far from the only utility industry application. As other industries are already showing, the sky is literally the limit when it comes to the potential uses for UAVs.”
Here, we take a look at some of the unique drone applications currently in place within Australian utilities.
A new network perspective
With close to 13,000 kilometres of high voltage transmission lines and 99 substations across New South Wales, TransGrid routinely inspects their network to ensure the safe and reliable supply of electricity to consumers.
Through a commitment to innovation, the NSW high voltage network operator has deployed Unmanned Aerial Vehicle (UAV) technology to gain a new perspective of their network while increasing efficiency and safety.
TransGrid currently undertakes several different inspection types including ground, climbing, easement, thermography and Light Detection and Ranging (LiDAR) across their state-wide network as part of their comprehensive maintenance program.
“The benefits to employee safety, the efficiencies in performing inspections and the steady uptake of UAVs by utility companies strongly signalled to TransGrid this technology is worth trialling,” said TransGrid’s Executive General Manager, Field Services, Michael Gatt.
“Our UAV pilot project aimed to test their application in providing results of equal or better quality than current inspection methods.”
Following a competitive tender process, TransGrid purchased a SkyJib X4 from Aeronavics with a specially configured payload system, which averages approximately 15 minutes of flight time. The configuration of the cross arms and motors are considered more stable in windy conditions, which is ideal when inspecting high voltage transmission towers which can measure up to 50 metres in height.
TransGrid’s UAV was quickly put into action following the issuing of a licence from the Civil Aviation Safety Authority (CASA) in late September 2015. A flight was undertaken to inspect a possible mid-span line defect, which had been identified during a routine aerial inspection.
The aerial inspection was not able to provide enough detail to staff on its exact nature, and access to the site by an elevated work platform was limited due recent weather (unless track remediation work was first conducted). To avoid both the need for extensive track remediation work and a line outage, the drone was brought in to inspect the line.
During the flight, the UAV took photos and video of the defect, which were downloaded onto a laptop and sent back to maintenance staff who not only confirmed their quality but also its nature. In its first official flight, the UAV resulted in a low cost, rapid response solution and provided staff with detailed information about the line defect.
During the trial period, a number of defects were targeted for inspection, including mid-span line defects, bent or damaged spacers, chipped insulators caps and rubbing high voltage jumpers on towers. It was quickly discovered that the UAV was able to provide excellent images and new angles on defects and equipment which were in obscure positions, without the need for a line outage.
The UAV was also utilised at one of TransGrid’s substations to identify what type of data would be useful to maintenance staff.
Without the need for an outage, the UAV was able to provide staff with a new perspective on the condition of substation gantry beams. Images from the flight will be used by staff to conduct assessments of the gantry beams’ structural integrity.
The UAV was also used to inspect the condition of substation rooves which helped to mitigate the need to climb, as well as providing staff with an overview of the entire roof of the building.
The results obtained from the flight will be used by staff to help determine if remedial work is required.
During the trial program, another possible use of the UAV was found for measuring tree clearances from conductors on easements. This new application was achieved by using telemetry from the UAV and measuring the altitude at tree height and the altitude of the conductor then subtracting the two results to obtain the clearance height. This has the potential to be used in hard to access gullies where this type of measurement would be difficult by traditional methods.
A number of important lessons were learned throughout the trial that will assist TransGrid’s approach to future inspections performed by the UAV.
“During the three week inspection trial, we were able to identify that inspections of line defects, substation gantry condition assessments, building condition assessments, easement clearances and thermography on defect basis are viable to be performed by the UAV,” said Mr Gatt.
Following the successful trial program, TransGrid will now seek to investigate other possible applications for the UAV as part of their maintenance program, including substation thermography, radio tower condition inspections, survey and land mapping and corona discharge inspections.
In the Northern Territory, Power and Water Corporation is also utilising UAVs to carry out asset inspections – and when you’re working with a network that spans more than a million square kilometres, the benefits UAVs can provide are obvious.
In 2015, the utility carried out a trial for the inspection of powerlines across the Territory. With more than 10,265km of powerlines that need to be inspected periodically to identify maintenance needs, Power and Water Corporation investigated the use of UAVs to supplement traditional inspection methods such as ground-based inspection, aerial inspection (from helicopter), climbing and elevated work platforms.
Each of these inspection methods has limitations related to access, viewing angles of the asset, time, cost and system security.
According to John Greenwood, General Manager Power Networks at Power and Water Corporation, a number of factors led to the utility undertaking its trial of UAVs.
“We identified drones as a means of asset inspection through discussions with other utilities, who generously shared their experiences on what had been successful, and what didn’t work so well.
“Coinciding with this was a general awareness of the growth in the drone services sector and an understanding of the new opportunities available. We were also approached directly by several service providers.”
Mr Greenwood says that while it’s early days in the utility’s journey into UAV inspection, they have seen promising results, particularly when using UAVs to confirm the severity of defects that have been observed from the ground.
“At this stage, we’re now focused on conducting some more research to understand the operating limitations, training and licensing requirements to ensure we fully understand the costs, resources and any statutory obligations prior to adopting the technology,” said Mr Greenwood.
“We’re also still considering whether we operate drone inspection in-house or through a contractor. Due to our proximity to larger service providers that have the licensing and training aspects in hand, having a solution that can be deployed quickly with limited mobilisation cost is a key consideration.”
While they’re still at an early stage in the process, Mr Greenwood can already see a number of future potential applications for the technology.
“I can see Power and Water utilising this technology for inspections of lines and easements including visual and thermography, vegetation management verification, and inspections of lines that are inaccessible due to flooding during the wet season, particularly if the line has tripped and the cause cannot be verified.”
In one of the more unique applications for utility drone use, Queensland water utility Seqwater recently undertook a trial of a UAV for the management of aquatic weeds on its lakes.
The innovative approach to treating floating aquatic weeds was initially trialled at Somerset Dam.
Seqwater Chief Executive Officer, Peter Dennis, said the trial sites were selected based on the difficulty to access the weed infestations by boat or shore.
“Some aquatic weeds are notoriously difficult to access, located either in between dead trees, under paperbark swamps or in shallow water. The location of these weeds has meant traditional treatment methods, such as boat-based or land-based spraying, could not be readily used.
“Managing difficult infestations requires more effort – staff may have to wade through water or use canoes to reach the weeds. In comparison, the UAV can be operated from the shoreline or a boat. It is flown remotely by a licensed pilot who is assisted by a spotter.
“The craft can carry up to 23kg, or 16 litres of herbicide at a time, and deliver a swath of herbicide 3.2m wide. Depending on the density of weed infestation and required coverage rates, a single tank of herbicide can last up to an hour,” said Mr Dennis.
Mr Dennis said there were three main species of floating aquatic weed infestations found in Seqwater drinking water storages, Salvinia, Water Lettuce and Water Hyacinth.
“The type of weed and abundance of infestation is predominantly dependent on seasonal influences and inflows following rain. The rate of growth increases over summer, while floodwaters can bring new weeds into the dam.
“Under favourable conditions, some species of aquatic weeds can double in size every four to five days. Floating aquatic weeds can have a number of negative impacts on water quality, including depleting dissolved oxygen levels and increasing nutrient loads within the lake.
While the utility is still observing the benefits of using UAVs for herbicide application, Mr Dennis is positive about the role they can play within Seqwater. “There is a great potential for the use of drones for herbicide application for both aquatic and terrestrial spraying. I look forward to learning more about their benefits for Seqwater,” said Mr Dennis.
Servicing the industry’s needs
Over the past six years, Select Solutions has implemented a dedicated UAV program supported by its senior executive and that of its parent, AusNet Services, and is now established as a leader in the use and operation of UAVs for asset inspection to complement its extensive inspection services in the utilities and rail industries.
While many are dabbling in the technology and investigating how it can be used effectively, Select Solutions is successfully operating a UAV program, having been the first utility in Australia to receive CASA licensing, and now has a continuous program of work supported by 15 trained operators and 17 UAVs.
The carefully selected UAV fleet comprises a mix of low-end off-the-shelf UAVs for close range imaging, and high-end aircraft to carry specialised payloads for targeted services such as thermal inspection, high resolution imagery inspection and aerial LiDAR inspection.
Select Solutions is pleased that members of the utilities fraternity are embracing the technology. “We are starting to see the effective deployment of UAV within the utilities industry to solve a variety of problems,” said John Perkins. “Most importantly, these projects have confirmed our views on the key success factors for implementing a UAV program.”
Select Solutions believes that the success of any UAV program is hinged on a number of key factors including integration of UAVs into existing workflows, understanding how to extract information and key insights from the UAV data, or how to achieve the expected benefits of using a UAV, and, primarily, reaching the understanding that the UAV is just another tool to get the job done, and isn’t the answer in itself.
It is clear from the examples above that Transgrid, Power and Water, Seqwater and Select Solutions are taking full advantage of the flexibility and power of a UAV platform in delivering positive business benefits across a range of applications.
There are many scenarios where utilities can use UAVs, however it is important to remain focused on developing capability that provides tangible business benefit. Select Solutions has the following key criteria for assessing the use of UAVs:
- Safety – can a UAV be used to improve the safety of our people or the general public?
- Productivity – is it faster or more productive to use a UAV?
- Unique perspective – does the UAV provide a unique perspective that cannot be achieved by other means?
- Access – does the UAV allow us to access areas that are otherwise beyond our reach?
- Complementary solution – will the UAV provide the total solution or will it be a fill-in solution for special scenarios?
- Cost – is it cheaper to utilise a UAV?