How National Grid step up when the heat is on
Resilience is key to extreme weather scenarios
Blistering temperatures might have brought a welcome waft of the Med for some earlier this year, but for the engineers we rely on to keep us cool the heat was very much on. Weeks before the mercury nudged 40 degrees in July, National Grid’s control centre teams were monitoring the looming weather patterns and planning ahead.
The Transmission Network Control Centre (TNCC) engineers worked closely with meteorologists from the Met Office to ensure the overhead lines, transformers and substation equipment were ready for everything Mother Nature could throw at them.
This resilience complements the year-round walking, helicopter and drone checks carried out on grantors’ land by National Grid’s engineers.
Public feedback is vital
Ed Maddams, National Grid’s Overhead Lines Zonal Support Engineer, says: “We also carry out LIDAR (Light Detection and Ranging) checks using laser technology to see if vegetation or new buildings could be an issue near our assets.
“If vegetation is too close there’s a risk of fire, so we also rely on feedback from the public if they’re concerned. But it’s not just hot weather that we prepare for – high winds, rain and extreme cold are also very much on our radar.”
Heath or grassland routes on the network where previous issues with fire near overhead lines have been reported are subject to extra patrols to check for emerging issues and material that could pose a fire hazard. This continued planning ensures the network operates efficiently and includes checks on overhead lines prone to sagging in extreme heat.
“The hotter the weather gets, the lower the lines drop and the less power we can send down them, so that has to be managed centrally. All our equipment is subject to standard maintenance regimes, with conductors and spacers flagged up on our system and replaced well before the end of their serviceable life.”
Ed Maddams, Overhead Lines Zonal Support Engineer, National Grid
That’s because a single piece of equipment affected by the rising temperature could mean an outage affecting thousands of homes and businesses. Ed adds: “Cooling fans and pumps are also checked to make sure they’re in good working order. We also constantly liaise with agencies such as the fire service and police to establish protocols in the unlikely event of an emergency.”
All assets are given a rating, with colder temperatures given a higher one and hotter temperatures a lower one. That allows the Electricity System Operator (ESO) to operate the network within set rating parameters so it won’t become overstressed and prevents assets from getting damaged.
"When necessary, additional control room staff can be deployed to help monitor for issues arising from excessive heat or cold. We’re continually monitoring the system for alarms or signs of overheating so we can do maintenance checks before they’re needed," says Ed.
The welfare and wellbeing of the teams briefed with venturing out in all conditions is also critical and special measures are taken to ensure they’re prepared – whatever the weather.
“The network is like a Swiss cheese made up of lots of layers, with failsafes built in. That and the people who operate it mean the public enjoy a safe and reliable electricity supply and take us for granted. Because if people don’t notice us, we’re doing it right.”
Ed Maddams, Overhead Lines Zonal Support Engineer, National Grid
