State-owned enterprise Transpower is investing in new technology to check its transmission lines and substations nationwide in a bid to cut costs, improve efficiency and increase safety.



The operator of the national grid is planning a shift to robots and unmanned aerial vehicles to check the lines and substations.



Transpower chief executive Patrick Strange said the company was willing to invest millions of dollars a year in new technology to potentially save millions more in costs.



Resilience had been restored in the grid after a five-year capital investment programme, Transpower said, and the company was now focusing on how to better use existing assets rather than building new ones.



Strange said a substation like the one at Drury, south of Auckland, was worth $20 million.



Transpower was looking at how new technology could help keep costs down and get more out of its existing stations, Strange said.



Using unmanned drones and remotely controlled robots to check substations and transmission lines would reduce callout times and restore power hours earlier in the event of an outage.



The company showed off the new technology today at its Drury substation as part of an International Committee on large Electric Systems (CIGRE) conference.



The technology that drew the most attention was the unmanned aerial vehicle (UAV).



The 3.5-metre-long mini-helicopter would be used to check transmission lines for damage, obstruction and outages, rather than sending out people on foot or in regular helicopters, the company said.



Transpower said current options were expensive and sometimes disruptive for landowners.



Each year, Transpower spent up to $4 million on scheduled ground-based inspections, and up to $600,000 on scheduled and non-scheduled helicopter inspections.



Using remotely piloted aerial vehicles would mean better flight safety, cost savings, shorter response times, more information collected and less disruption to landowners, it said.



Strange said the company already used some "pretty hi-tech stuff", but drones and robots were the next step.



"What you're seeing today is tomorrow's technology."



Transpower senior principal engineer Andrew Renton said the company did not yet own a UAV but planned to buy two aircraft and a ground control station from Austrian manufacturer Schiebel.



Renton would not say exactly how much the technology would cost to buy.



"It's expensive and it's in the millions of dollars."



Strange said he expected the company to have the UAVs in Transpower's network within the next 2-1/2 years. Schiebel had been developing its drone since 2006.



The drone has a range of a 400-kilometre radius, a maximum altitude of 5km, and can fly up to about 180kmh but flies at only 30kmh while patrolling. It has high-definition and infa-red cameras.



Transpower was also trialling a transmission line robot and a substation 4x4 all-terrain robot as part of its systems improvement programme.



The substation robot was still in its prototype phase and the line robot was being developed to allow for use on live lines, Transpower said.



Strange said he expected the robots to be fully developed and in the network within the next couple of years.



The push towards new technology would not result in redundancies, Strange said.



While the robots would mean a change in people's jobs, the company had plenty of work available, he said.



"If you want a career for life, become a lineman."