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Some of TLC's 4,036 km of overhead lines spanning the King Country-Ruapehu region

Local electricity lines more than meet challenge of increased demand during heat wave

1 February 2019

While the country baked under the heat wave since earlier in the week, The Lines Company’s (TLC) power lines delivered customers uninterrupted supply despite the hotter than normal conditions.

As seen on the Wellington rail network, overhead lines can be affected by hot weather. Being higher up lines are susceptible to increases in heat from the sun. When combined with naturally occurring heat from distributing power, lines can expand, sag and cause problems, especially mid-span.

“The network’s monitored 24/7 and all transformers have fans fitted to cool them automatically, but with the unprecedented hot weather we’ve been keeping a special eye on all our zone substations,” says network general manager, Mike Fox.

Temperatures in Taumarunui and Te Kūiti hit record highs on Tuesday and electricity demand matched peak winter demand. Usage was higher throughout the middle of the day, likely due to greater use of air conditioners as people tried to stay cool.

“We weren’t load controlling and since the heat wave began there’s been no heat-related supply interruptions for our customers. That all points to our network being resilient to deal with these kinds of conditions,” Mr Fox says.

And his tips for those wanting to get the most of the electricity they use during hot weather?

  • Check and clean air conditioning unit filters, and then set and keep it at a steady temperature, for example, 22 degrees, so it doesn’t have to work as hard.
  • Close curtains and blinds during the heat of the day to reduce heat from the sun.
  • Leave the vacuuming, laundry, ironing and other heavy day-use activities to the evening if you can.
  • Cook outdoors on the BBQ to help avoid the extra heat given off by your stove or oven.
  • Take a cool shower before bed to cool your body temperature and help you sleep.

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