But lots of water in lakes does not mean prices are going to head down.
In a monthly report, Meridian Energy chief executive Mike Roan said January had seen a continuation of wet summer conditions and high lake levels.
"We are in a really solid position as we move towards autumn. Both water and snow storage in the Waitaki catchment are well above historical averages for this time of year, putting the country in a good position ahead of the coming winter," he said.
"Extended periods of spilling in both the Waitaki and Waiau catchments have now ended but drove wholesale prices to remarkably low levels in January. Our average generation sales price was just over $1 per megawatt hour last month."
In August 2024, when power supplies were tight, wholesale electricity prices rose from roughly $300 a MWh to over $800 a MWh.
Lots of water, though, does not lead to lower prices. Consumer NZ is tipping electricity prices to rise by 5% this year, following a double-digit increase last year.
A Meridian Energy spokesman said he understood how people might expect the low wholesale prices might flow through to their power bills.
"It does — but only indirectly and only if sustained. The rates we use in customer contracts are based on average prices over time. They factor in low price points like we’re seeing now, but also times when wholesale prices are much higher.
"If we see sustained periods of lower wholesale prices, residential prices will come down and that’s something you can expect to see over time as a lot more renewable generation is built."
The main factor behind the price changes was increases to lines and transmission charges — the fixed costs of the networks used for getting electricity from power stations to homes, he said.
Meridian’s generation last month was 14.5% higher than the same month last year.
The average price Meridian received for its generation last month was 98.9% lower than the same month last year.
To date this financial year, total inflows were 138% of historical average, the second highest July to January inflows on record.
In the month to February 9, national hydro storage dropped from 135% to 117% of historical average.
South Island storage decreased to 110% of average and North Island storage decreased to 162% of average by February 9, 2026.
