Grid owners can save NOK millions
“Much of this cost is due to disconnections for scheduled work. Live working means a considerable reduction in power disconnections, which of course means more satisfied customers,” he continues.
On the island of Asmaløy in Hvaler municipality in southern Norway, a line disconnect switch has jammed in the 20 kV distribution network. Norgesnett faces the choice of disconnecting the power for thousands of homes and holiday cabins further out in the Hvaler archipelago, disconnecting extensive sections of the high-voltage grid, or using live working to correct the fault.
“Many people use their cabins out there as remote offices over the long weekends, with PCs and other equipment that need power,” explains Borge. “Both those customers and the permanent residents need to be notified in the event of a planned power outage. And even though we do provide a warning, individual customers can understandably become irritated. A lot of them phone up Customer Services, and it has a negative effect on our reputation. One important factor is that we also face increased costs for energy not supplied. Besides, live working methods are at least as efficient. At Norgesnett, we have now really put live working on the agenda, and we will definitely be using this expertise much more in the future,” he emphasises. Together with his team, Borge is able to observe the repair work on the switch on Asmaløy close-up, as Infratek’s engineers drive the four-wheel-drive truck with its cherry-picker along the rocky shore.
Engineers Erlend Teig and Lindulf Gaustad give a step-by-step explanation of the work to those present. The duo leave no doubt: safety first. “It’s all about controlling the risk factors,” explains Erlend Teig.
The REN (“Rational Electricity Grid Operations”) organisation is holding workshops on live working on 20 and 21 September at Gardermoen. Infratek will be taking part to demonstrate the technique. Infratek is one of the few companies with extensive experience of the working method.
“The personnel we use for live working, such as Erlend and Lindulf, are highly experienced, and they have extensive training and a fundamentally sound level of technical expertise,” confirms Kjell Løvbakken, department manager for Infratek. “Without the right know-how, this is a challenging and hazardous job. We take on live working assignments whatever the accessibility or terrain. It’s vital to have all the right equipment and to be fully trained in how to use it. A lot of live working installers say that they actually feel safer when working live, as then all of the risk factors are under their control. Statistics from various countries where live working is more common than in the Nordic region also confirm that live working actually is a safer working method than working on disconnected equipment,” he states.
Another advantage of live working is that it ensures full redundancy in the power grid.
Norgesnett AS is a wholly-owned subsidiary of Fredrikstad Energi AS, and, through its area concession, is responsible for the power grid in the municipalities of Fredrikstad (excluding Onsøy), Hvaler, Nesodden, Røyken, Enebakk, Ski and Askøy. Norgesnett has approximately 93,000 customers.
Norgesnett’s department manager, Arild Borge (in the blue hardhat) and Infratek’s department manager, Kjell Løvbakken (left) observe the work on Asmaløy close-up.