Far North farmers are preparing for a day without power on Sunday while Top Energy carries out maintenance.
Okaihau dairy farmer Terence Bronx said the biggest impacts would be to stock water and electric fences.
"If it's a hot day, those cows will be hanging out for some water. Some farms that have got gravity feed systems will be okay, but the majority of farms, they'll be running out of water."
Bronx said the electric fences without power would certainly also be an issue.
"Probably more so for younger stock, calves, that type of thing. But also for the beef farmers, particularly bull farmers, they will be very much be challenged by not having any power on their fences."
Joe King, who had a family farm on the Awanui straight, reckoned he could "bluff" the bulls for a day into believing electric fences were still live. He had two dairy farms on flat land and his main concern was stock water.
"I know that Fonterra will be organising their tankers to pick up the milk as soon as we've finished milking. But then we still have to worry about water for the cows."
Top Energy spokesperson Philippa White nine hours of outage was required due to the nature of the work, which needed to be undertaken in one go.
She said Top Energy was investing significantly in diesel generators and hoped also to have the solutions for farmers in the future.
"We anticipate by 2020 we will not require outages of the duration and scale required in this weekend's Kaitaia outage."
Joe King's wife Fiona said the length of the planned outage, from 8am to 5pm, would put huge pressure on farmers during a dry November.
"A cow drinks 70 litres of water a day. Then you add a herd of 600 cows and imagine how much water that is.
"All farms are run on electric fences these days. With no fences [live] then you have the risk of animals getting out on the state highway. Especially if they're looking for water."
Their son Logan who has been running the farm said the power outage has meant a lot of planning and expense.
"We'll plug a 25 thousand litre water tank to where the cows are going to be that day. That involves having a $3000 water tank, for each farm. And we also have to try put it on something high enough [to use gravity to top up the trough]."
Houhora beef farmer Jeremy White had a main road running down the middle of his farm so moving the stock wasn't an easy option. He would be relying on tree shade and hoping for an overcast day.
"They're drinking a lot of water at the moment, it's pretty hot and dry."
White said a power outage for nine consecutive hours was too long for farmers.
"They'd never shut the power off in Auckland for nine hours in a row to do maintenance. They'd never get away with it.
"I understand it's got to be done, but I'm sure you could do it some other way."
Terence Bronx said he understood the power outage was a sacrifice needed to improve the infrastructure.
"That is so important, to make our power supplies more reliable.
"It certainly has a big impact to try and work around it. And most of it should be able to be managed, but the stock water and the electric fences will be the challenge."
Meanwhile, White said many pickers and growers in the area would have the day off.
Dairy farmers, however, would be working overtime - or paying for it - to milk around the power outage, King said.
"Farmers don't have days off. Especially dairy farmers."